/* ===== 全局与背景：浅色科技风 ===== */

*,
*::before,
*::after {
  box-sizing: border-box;
}

.source-row label {
    text-transform: none !important;
}


body {
  margin: 0;
  padding: 0;
  font-family: 'Roboto', sans-serif;
  color: #111827;
  background: #f3f4f6; /* ⭐ 整体浅灰白背景 */
}

/* 页面骨架 */
.page {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.app-footer-credit {
  padding: 10px 24px 14px;
  text-align: center;
  color: #64748b;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.04em;
}

/* ===== 顶部导航 ===== */

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 24px;
  background: #ffffff;
  border-bottom: 1px solid #e5e7eb;
  backdrop-filter: blur(12px);
  gap: 16px;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  font-weight: 900;
  font-size: 18px;
  letter-spacing: 0.03em;
  text-transform: none;
  color: #0f172a;
  white-space: nowrap;
  line-height: 1;
  background: linear-gradient(135deg, #0f172a 0%, #0369a1 50%, #16a34a 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-shadow: 0 10px 24px rgba(14, 165, 233, 0.08);
}

.logo-img {
  width: 38px;
  height: 38px;
  border-radius: 9px;
  object-fit: cover;
  flex: 0 0 auto;
  box-shadow:
    0 8px 18px rgba(15, 23, 42, 0.18),
    0 0 0 1px rgba(148, 163, 184, 0.28);
}

.logo-dot {
  width: 13px;
  height: 13px;
  border-radius: 999px;
  background: radial-gradient(circle at 30% 30%, #60a5fa 0%, #2563eb 46%, #14b8a6 100%);
  box-shadow:
    0 0 0 4px rgba(14, 165, 233, 0.12),
    0 0 18px rgba(59, 130, 246, 0.72);
  flex: 0 0 auto;
}

.kb-info {
  font-size: 13px;
  color: #6b7280;
  white-space: nowrap;
}

/* ===== 主体布局：左右两栏 ===== */

.main {
  flex: 1;
  display: grid;

  /* 左边：窄的（知识库），右边：宽的（生成器） */
  grid-template-columns: minmax(260px, 1fr) minmax(0, 2.1fr);
  grid-template-areas: "right left";

  gap: 18px;
  padding: 18px 24px 24px;
}


@media (max-width: 900px) {
  .main {
    grid-template-columns: minmax(0, 1fr);
    /* 小屏幕时改成上下排：上 left，下 right */
    grid-template-areas:
      "left"
      "right";
  }

  .left-panel,
  .right-panel {
    grid-column: auto;  /* 防止旧的 grid-column 干扰 */
  }
}


/* ===== 左侧：聊天卡片 ===== */

.left-panel {
  /* 原：grid-column: 2;  ❌ 改成区域名 */
  grid-area: left;

  display: flex;
  flex-direction: column;
  background: #ffffff;
  border-radius: 16px;
  padding: 16px 16px 12px;
  border: 1px solid #e5e7eb;
  box-shadow:
    0 18px 40px rgba(15, 23, 42, 0.06),
    0 0 0 1px rgba(15, 23, 42, 0.02);
}

/* 标题区域 */
.panel-header {
  margin-bottom: 10px;
}

.panel-title {
    font-family: 'Playfair Display', serif !important;
  font-size: 36px;  /* 根据需要调整 */
  font-weight: 600;
  color: #111827;
  text-align: center;  /* 确保居中对齐 */
}

.gradient-text {
  background: linear-gradient(135deg, #0ea5e9, #22c55e); /* 蓝绿渐变 */
  -webkit-background-clip: text; /* 使背景应用到文本 */
  color: transparent; /* 使文字透明，显示渐变色 */
  font-weight: 600; /* 可选，增加字体的粗细 */
}

.panel-subtitle {
  font-size: 16px;
  color: #6b7280;
  margin-top: 2px;
}

/* 聊天窗口 */
.chat-window {
  flex: 1;
  min-height: 320px;
  max-height: 540px;
  overflow-y: auto;
  padding: 10px;
  border-radius: 12px;
  background: #f9fafb;
  border: 1px solid #e5e7eb;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

/* 单题卡片 + 左右切换按钮布局 */
.question-card-wrapper {
  flex: 1;
  display: flex;
  align-items: stretch;
  justify-content: center;
  gap: 12px;
}

.question-nav-btn {
  width: 38px;
  min-width: 38px;
  border-radius: 999px;
  border: none;
  background: linear-gradient(135deg, #0ea5e9, #22c55e);
  color: #ffffff;
  font-size: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: 0 6px 16px rgba(37, 99, 235, 0.35);
  transition: transform 0.12s ease, box-shadow 0.12s ease, opacity 0.12s ease;
}

.question-nav-btn:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 10px 20px rgba(37, 99, 235, 0.35);
}

.question-nav-btn:disabled {
  opacity: 0.35;
  box-shadow: none;
  cursor: default;
}

.question-card {
  flex: 1;
  display: flex;
  flex-direction: column;
  padding: 14px 16px;
  border-radius: 16px;
  background: #ffffff;
  border: 1px solid #e5e7eb;
  box-shadow: 0 10px 24px rgba(15, 23, 42, 0.06);
  min-height: 280px;
  max-height: 480px;
}

.question-card-header {
  font-size: 14px;
  font-weight: 600;
  color: #0f172a;
  margin-bottom: 8px;
}

.question-card-body {
  flex: 1;
  font-size: 14px;
  line-height: 1.8;
  color: #111827;
  white-space: pre-wrap;
  overflow-y: auto;
  padding-right: 4px;
  margin-bottom: 10px;
}

.answer-area {
  border-top: 1px dashed #e5e7eb;
  padding-top: 8px;
  margin-top: 4px;
}

.answer-label {
  font-size: 12px;
  color: #6b7280;
  margin-bottom: 4px;
}

.answer-input {
  width: 100%;
  min-height: 80px;
  max-height: 140px;
  resize: vertical;
  border-radius: 10px;
  border: 1px solid #d1d5db;
  padding: 8px 10px;
  font-size: 14px;
  line-height: 1.5;
  outline: none;
}

.answer-input:focus {
  border-color: #0ea5e9;
  box-shadow: 0 0 0 1px rgba(14, 165, 233, 0.4);
}

/* 错误提示 */
.error-hint {
  padding: 10px 12px;
  border-radius: 10px;
  background: #fef2f2;
  border: 1px solid #fecaca;
  color: #991b1b;
  font-size: 13px;
  line-height: 1.5;
}


/* 自定义滚动条 */
.chat-window::-webkit-scrollbar {
  width: 6px;
}

.choice-answer-group {
  display: grid;
  grid-template-columns: repeat(4, minmax(58px, 1fr));
  gap: 10px;
}

.choice-answer-btn {
  min-height: 48px;
  border: 1px solid #cbd5e1;
  border-radius: 12px;
  background: #ffffff;
  color: #0f172a;
  font-size: 18px;
  font-weight: 800;
  cursor: pointer;
  transition: border-color 0.15s ease, background 0.15s ease, box-shadow 0.15s ease, transform 0.15s ease;
}

.choice-answer-btn:hover {
  border-color: #0ea5e9;
  background: #f0f9ff;
  transform: translateY(-1px);
}

.choice-answer-btn.selected {
  border-color: #0ea5e9;
  background: linear-gradient(135deg, #0ea5e9 0%, #14b8a6 55%, #22c55e 100%);
  color: #ffffff;
  box-shadow: 0 8px 18px rgba(14, 165, 233, 0.25);
}

.question-prompt-text {
  margin-bottom: 14px;
  white-space: pre-wrap;
}

.question-choice-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
  margin-top: 8px;
}

.question-choice-btn {
  width: 100%;
  min-height: 48px;
  display: grid;
  grid-template-columns: 38px minmax(0, 1fr);
  align-items: center;
  gap: 12px;
  padding: 10px 14px;
  border: 1px solid #cbd5e1;
  border-radius: 12px;
  background: #ffffff;
  color: #0f172a;
  font: inherit;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
  transition: border-color 0.15s ease, background 0.15s ease, box-shadow 0.15s ease, transform 0.15s ease;
}

.question-choice-btn:hover {
  border-color: #0ea5e9;
  background: #f0f9ff;
  transform: translateY(-1px);
}

.question-choice-btn.selected {
  border-color: #0ea5e9;
  background: linear-gradient(135deg, rgba(14, 165, 233, 0.12) 0%, rgba(34, 197, 94, 0.12) 100%);
  box-shadow: 0 8px 18px rgba(14, 165, 233, 0.16);
}

.question-choice-letter {
  width: 32px;
  height: 32px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 999px;
  background: #e0f2fe;
  color: #0369a1;
  font-weight: 900;
}

.question-choice-btn.selected .question-choice-letter {
  background: linear-gradient(135deg, #0ea5e9 0%, #22c55e 100%);
  color: #ffffff;
}

.question-choice-text {
  min-width: 0;
  overflow-wrap: anywhere;
}

@media (max-width: 640px) {
  .choice-answer-group {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.chat-window::-webkit-scrollbar-track {
  background: transparent;
}
.chat-window::-webkit-scrollbar-thumb {
  background: #d1d5db;
  border-radius: 999px;
}

/* 聊天气泡 */
.msg {
  max-width: 80%;
  padding: 9px 11px;
  border-radius: 14px;
  font-size: 14px;
  line-height: 1.6;
  white-space: pre-wrap;
}

/* 用户消息：右侧蓝绿渐变气泡 */
.msg-user {
  margin-left: auto;
  background: linear-gradient(135deg, #22c55e, #0ea5e9, #6366f1);
  color: #f9fafb;
  box-shadow:
    0 12px 24px rgba(56, 189, 248, 0.45),
    0 0 0 1px rgba(15, 23, 42, 0.2);
}

/* 机器人消息：左侧浅灰卡片 */
.msg-bot {
  margin-right: auto;
  background: #ffffff;
  color: #111827;
  border: 1px solid #e5e7eb;
  box-shadow: 0 4px 10px rgba(15, 23, 42, 0.04);
}

/* 机器人消息中的链接样式 */
.msg-bot a {
  color: #2563eb;
  text-decoration: none;
}
.msg-bot a:hover {
  text-decoration: underline;
}

/* ===== 输入区域 ===== */

.input-row {
  margin-top: 12px;
  display: flex;
  /* ⭐ 改成横向排 + 反向，把按钮这块放在最左边 */
  flex-direction: row-reverse;
  /* 垂直方向居中，让按钮和“题型/数量”在同一水平线上 */
  align-items: center;
  gap: 10px;
}


/* Source 开关行 */
.source-row {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 12px;
  font-size: 11px;
  color: #6b7280;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  flex: 1;                /* ⭐ 让 “题型/数量” 这一块撑满右侧空间 */
}


.source-label {
  opacity: 0.9;
}

.question-toolbar-label {
  color: #475569;
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: none;
  opacity: 1;
}

.question-type-group {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px;
  border: 1px solid #dbe4ef;
  border-radius: 16px;
  background: #f8fafc;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.8);
}

.question-type-option {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 0 14px;
  border-radius: 12px;
  cursor: pointer;
  border: 1px solid transparent;
  background: transparent;
  color: #334155;
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: none;
  transition: color 0.15s ease, transform 0.15s ease, background 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease;
}

.question-type-option input {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.question-type-option span {
  position: relative;
  z-index: 1;
  color: inherit;
}

.question-type-option::before {
  content: none;
}

.question-type-option:hover {
  transform: translateY(-1px);
  background: #ffffff;
  border-color: #cbd5e1;
}

.question-type-option:has(input:checked) {
  color: #ffffff;
  background: linear-gradient(135deg, #0ea5e9 0%, #14b8a6 55%, #22c55e 100%);
  border-color: transparent;
  box-shadow: 0 10px 18px rgba(14, 165, 233, 0.22);
}

.question-count-control {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 52px;
  padding: 6px 10px 6px 12px;
  border: 1px solid #dbe4ef;
  border-radius: 16px;
  background: #ffffff;
  box-shadow: 0 8px 18px rgba(15, 23, 42, 0.05);
}

#question-count {
  width: 72px;
  min-height: 40px;
  border: 1px solid #cbd5e1;
  border-radius: 12px;
  background: #f8fafc;
  color: #0f172a;
  font-size: 15px;
  font-weight: 800;
  text-align: center;
  outline: none;
}

#question-count:focus {
  border-color: #0ea5e9;
  background: #ffffff;
  box-shadow: 0 0 0 3px rgba(14, 165, 233, 0.14);
}

@media (max-width: 980px) {
  .source-row {
    justify-content: flex-start;
    flex-wrap: wrap;
  }

  .question-type-group {
    width: 100%;
    justify-content: space-between;
    flex-wrap: wrap;
  }

  .question-type-option {
    flex: 1 1 160px;
  }
}

/* 滑动开关整体 */
.toggle {
  position: relative;
  display: inline-flex;
  align-items: center;
  cursor: pointer;
  user-select: none;
}

.toggle input {
  display: none;
}

/* 背景轨道：浅色玻璃感 */
.toggle-track {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 200px;
  padding: 3px 4px;
  border-radius: 999px;
  background: #f3f4f6;
  border: 1px solid #e5e7eb;
  box-shadow:
    0 6px 16px rgba(15, 23, 42, 0.06),
    0 0 0 1px rgba(148, 163, 184, 0.3);
  overflow: hidden;
}

/* 滑块：彩色渐变 */
.toggle-thumb {
  position: absolute;
  top: 4px;
  left: 4px;
  width: 96px;
  height: 28px;
  border-radius: 999px;
  background: linear-gradient(135deg, #22c55e, #0ea5e9, #6366f1);
  box-shadow: 0 10px 24px rgba(56, 189, 248, 0.45);
  transition: transform 0.22s ease;
}

/* 文本 */
.toggle-text {
  position: relative;
  z-index: 1;
  width: 50%;
  text-align: center;
  font-size: 11px;
  font-weight: 500;
  color: #9ca3af;
}

.toggle-text.left {
  padding-left: 4px;
}

.toggle-text.right {
  padding-right: 4px;
}

/* 选中 Scholar 时滑块右移 + 文本高亮 */
.toggle input:checked + .toggle-track .toggle-thumb {
  transform: translateX(96px);
}

.toggle input:not(:checked) + .toggle-track .toggle-text.left {
  color: #111827;
}
.toggle input:checked + .toggle-track .toggle-text.right {
  color: #111827;
}

/* 文本输入 + 发送按钮 */
.textarea-row {
  display: flex;
  gap: 12px;
  align-items: center;
  flex-wrap: wrap;
}

#user-input {
  flex: 1;
  min-height: 60px;
  max-height: 140px;
  resize: vertical;
  padding: 9px 11px;
  border-radius: 14px;
  border: 1px solid #d1d5db;
  background: #ffffff;
  color: #111827;
  font-size: 14px;
  outline: none;
}

#user-input::placeholder {
  color: #9ca3af;
}

#user-input:focus {
  border-color: #2563eb;
  box-shadow:
    0 0 0 1px #2563eb,
    0 0 0 1px rgba(37, 99, 235, 0.15);
}

/* 发送按钮：渐变 + 轻微阴影 */
#send-btn {
  border: none;
  border-radius: 999px;
  padding: 9px 18px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  color: #ffffff;
  background: linear-gradient(135deg, #22c55e, #0ea5e9, #6366f1);
  box-shadow:
    0 8px 20px rgba(56, 189, 248, 0.4),
    0 0 0 1px rgba(15, 23, 42, 0.15);
  transition: transform 0.08s ease, box-shadow 0.08s ease, filter 0.08s ease;
}

#send-btn:hover {
  filter: brightness(1.05);
  transform: translateY(-1px);
}

#send-btn:active {
  transform: translateY(0);
  box-shadow:
    0 4px 12px rgba(56, 189, 248, 0.3),
    0 0 0 1px rgba(15, 23, 42, 0.2);
}

#send-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.difficulty-control {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 48px;
  padding: 6px 8px 6px 12px;
  border: 1px solid #dbe4ef;
  border-radius: 16px;
  background: #ffffff;
  box-shadow: 0 8px 18px rgba(15, 23, 42, 0.05);
}

.difficulty-label {
  color: #475569;
  font-size: 14px;
  font-weight: 800;
}

.difficulty-group {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px;
  border: 1px solid #e2e8f0;
  border-radius: 14px;
  background: #f8fafc;
}

.difficulty-option {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 44px;
  min-height: 34px;
  padding: 0 12px;
  border-radius: 10px;
  border: 1px solid transparent;
  background: transparent;
  color: #334155;
  font-size: 13px;
  font-weight: 800;
  cursor: pointer;
  transition: transform 0.15s ease, background 0.15s ease, color 0.15s ease, box-shadow 0.15s ease;
}

.difficulty-option input {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.difficulty-option:hover {
  transform: translateY(-1px);
  background: #ffffff;
}

.difficulty-option:has(input:checked) {
  background: linear-gradient(135deg, #0ea5e9 0%, #14b8a6 55%, #22c55e 100%);
  color: #ffffff;
  box-shadow: 0 8px 16px rgba(14, 165, 233, 0.22);
}

/* ===== 右侧：知识库面板 ===== */

.right-panel {
  /* 原：grid-column: 1;  ❌ 改成区域名 */
  grid-area: right;

  display: flex;
  flex-direction: column;
  background: #ffffff;
  border-radius: 16px;
  padding: 16px;
  border: 1px solid #e5e7eb;
  box-shadow:
    0 18px 40px rgba(15, 23, 42, 0.06),
    0 0 0 1px rgba(15, 23, 42, 0.02);
  font-size: 14px;
}

/* 给 "Knowledge Base" 部分添加边框样式 */
.bordered-box {
  margin-top: 16px;
  padding: 12px 14px;
  border-radius: 12px;
  background-color: #f9fafb;
  border: 1px solid #e5e7eb;
}

.right-panel h2 {
  margin: 0;
  font-size: 15px;
  font-weight: 600;
  color: #111827;
}

.hint {
  margin: 6px 0 12px;
  color: #6b7280;
  font-size: 13px;
}

.hint code {
  font-family: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Monaco,
    Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 12px;
  padding: 1px 4px;
  border-radius: 4px;
  background: #f9fafb;
  border: 1px solid #e5e7eb;
}

/* 上传区域 */
.upload-box {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 10px;
}

#file-input {
  font-size: 13px;
  color: #374151;
}

#upload-btn {
  width: 100%;
  padding: 7px 0;
  border: none;
  border-radius: 999px;
  background: linear-gradient(135deg, #22c55e, #16a34a);
  color: #ffffff;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  box-shadow:
    0 10px 22px rgba(34, 197, 94, 0.4),
    0 0 0 1px rgba(15, 23, 42, 0.12);
  transition: transform 0.08s ease, box-shadow 0.08s ease, filter 0.08s ease;
}

#upload-btn:hover {
  filter: brightness(1.04);
  transform: translateY(-1px);
}

#upload-btn:active {
  transform: translateY(0);
  box-shadow:
    0 4px 12px rgba(34, 197, 94, 0.35),
    0 0 0 1px rgba(15, 23, 42, 0.16);
}

/* === 过往试卷上传区：沿用 Knowledge Base 的样式 === */

#past-exam-file-input {
  font-size: 13px;
  color: #374151;
}

#past-exam-upload-btn {
  width: 100%;
  padding: 7px 0;
  border: none;
  border-radius: 9999px;
  background: linear-gradient(90deg, #0ea5e9, #22c55e);
  color: #fff;
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  box-shadow:
    0 10px 25px rgba(34, 197, 94, 0.35),
    0 0 0 1px rgba(15, 23, 42, 0.12);
  transition: transform 0.08s ease, box-shadow 0.08s ease, filter 0.08s ease;
}

#past-exam-upload-btn:hover {
  filter: brightness(1.04);
  transform: translateY(-1px);
}

#past-exam-upload-btn:active {
  transform: translateY(0);
  box-shadow:
    0 4px 12px rgba(34, 197, 94, 0.35),
    0 0 0 1px rgba(15, 23, 42, 0.16);
}


#upload-btn:disabled {
  opacity: 0.65;
  cursor: not-allowed;
}

.upload-result {
  margin-top: 8px;
  font-size: 13px;
  color: #4b5563;
  white-space: pre-wrap;
}

/* 小提示卡片 */
.tip-box {
  margin-top: 16px;
  padding: 10px 10px 10px;
  border-radius: 12px;
  background: #f9fafb;
  border: 1px solid #e5e7eb;
}

.tip-title {
  font-size: 13px;
  font-weight: 500;
  margin-bottom: 6px;
  color: #111827;
}

.tip-box ul {
  margin: 0;
  padding-left: 18px;
  font-size: 12px;
  color: #6b7280;
}

.tip-box li + li {
  margin-top: 4px;
}

/* ⭐ 题目提交与批改结果区域 */
.card-actions {
  margin-top: 12px;
  display: flex;
  flex-direction: column;      /* ⭐ 改成纵向排列 */
  align-items: flex-start;
  gap: 8px;                    /* 上下间距稍微小一点 */
  justify-content: flex-start;
}

/* 让 “Got it / Not clear / Detailed Explanation” 三个按钮一行排列并留间距 */
.understand-row {
  display: flex;
  flex-wrap: wrap;      /* 一行放不下时自动换行 */
  gap: 8px;             /* 三个按钮之间的水平/垂直间隔 */
  align-items: center;
}


/* === 情景迁移练习区域 === */
.scenario-section {
  margin-top: 12px;
  padding-top: 10px;
  border-top: 1px dashed #e5e7eb;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.scenario-title {
  font-size: 13px;
  font-weight: 600;
  color: #0f172a;
}

.scenario-desc {
  font-size: 12px;
  color: #6b7280;
}

.scenario-btn {
  align-self: flex-start;
  padding: 4px 10px;
  border-radius: 999px;
  border: none;
  background: linear-gradient(135deg, #22c55e, #0ea5e9);
  color: #ffffff;
  font-size: 12px;
  cursor: pointer;
  box-shadow: 0 4px 10px rgba(34, 197, 94, 0.3);
  transition: transform 0.12s ease, box-shadow 0.12s ease, opacity 0.12s ease;
}

.scenario-btn:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 6px 14px rgba(34, 197, 94, 0.35);
}

.scenario-btn:disabled {
  opacity: 0.45;
  box-shadow: none;
  cursor: default;
}

.scenario-question-box {
  margin-top: 4px;
  padding: 8px 10px;
  border-radius: 8px;
  background: #f9fafb;
  border: 1px solid #e5e7eb;
  font-size: 13px;
  color: #111827;
  white-space: pre-wrap;
}

.scenario-answer-label {
  font-size: 12px;
  color: #6b7280;
}

.scenario-answer-input {
  width: 100%;
  min-height: 70px;
  padding: 6px 8px;
  border-radius: 8px;
  border: 1px solid #e5e7eb;
  font-size: 13px;
  resize: vertical;
}

.scenario-actions {
  margin-top: 6px;
  display: flex;
  gap: 10px;
  align-items: flex-start;
}

/* Scenario Practice 弹窗里的 “Submit Answer” 按钮 */
.scenario-submit-btn {
  padding: 6px 12px;              /* 和右边两个按钮保持一致 */
  border-radius: 999px;
  border: none;
  background: linear-gradient(135deg, #6366f1, #a855f7);
  color: #ffffff;
  font-size: 13px;                /* 和 I Understand / I Don't Understand 一样 */
  cursor: pointer;
  box-shadow: 0 4px 10px rgba(79, 70, 229, 0.35);
  transition: transform 0.12s ease, box-shadow 0.12s ease, opacity 0.12s ease;
}


.scenario-submit-btn:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 6px 14px rgba(79, 70, 229, 0.4);
}

.scenario-submit-btn:disabled {
  opacity: 0.6;
  box-shadow: none;
  cursor: default;
}

.scenario-grade-result {
  flex: 1;
  font-size: 12px;
  color: #374151;
  line-height: 1.4;
  white-space: pre-wrap;
}

/* 底部导航中间区域：竖向排列“反馈 + 情景迁移入口” */
.exam-nav-center {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

/* 底部导航右侧：让“下一题”和“问卷填写”上下排列，靠右对齐 */
/* 底部导航右侧：让“下一题”和“问卷填写”上下排列，靠右对齐 */
.exam-nav-right {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 6px;
}

/* Start Questionnaire 按钮：更明显的渐变色 + 向下挪一点 */
.survey-btn {
  margin-top: 22px;                 /* ⬅ 往下挪一点，接近右下角 */
  padding: 8px 20px;
  border-radius: 999px;
  border: none;
  background: linear-gradient(135deg, #f97316, #ec4899); /* 橙 → 粉 渐变 */
  color: #ffffff;
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 8px 20px rgba(236, 72, 153, 0.35);
  transition: transform 0.12s ease, box-shadow 0.12s ease, filter 0.12s ease;
}

.survey-btn:hover {
  filter: brightness(1.06);
  transform: translateY(-1px);
  box-shadow: 0 12px 26px rgba(236, 72, 153, 0.45);
}




/* 情景迁移入口在底部时去掉题卡里的虚线分割线，并居中 */
.scenario-entry-inline {
  margin-top: 0;
  padding-top: 0;
  border-top: none;
  align-items: center;
  text-align: center;
}

.scenario-entry-inline .scenario-desc {
  max-width: 560px;
}

.scenario-entry-inline .scenario-btn {
  align-self: center;
}


/* ===========================
   📚 过往试卷题库样式
   =========================== */

.exam-db-box {
  margin-top: 16px;
  padding: 12px 14px;
  border-radius: 12px;
  background-color: #f9fafb;
  border: 1px solid #e5e7eb;
}

.exam-db-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 8px;
}

.exam-db-title {
  font-size: 14px;
  font-weight: 600;
  color: #111827;
}

.exam-db-meta {
  font-size: 12px;
  color: #6b7280;
}

.exam-db-input textarea {
  width: 100%;
  min-height: 60px;
  resize: vertical;
  padding: 6px 8px;
  border-radius: 8px;
  border: 1px solid #d1d5db;
  font-size: 12px;
  font-family: inherit;
}

.exam-db-input-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 6px;
  align-items: center;
}

.exam-db-input-row label {
  font-size: 12px;
  color: #4b5563;
}

.exam-db-input-row input,
.exam-db-input-row select {
  margin-left: 4px;
  padding: 2px 6px;
  border-radius: 6px;
  border: 1px solid #d1d5db;
  font-size: 12px;
}

.exam-db-input-row button {
  margin-left: auto;
  padding: 6px 10px;
  border-radius: 9999px;
  border: none;
  background: #0ea5e9;
  color: white;
  font-size: 12px;
  cursor: pointer;
}

.exam-db-input-row button:hover {
  background: #0284c7;
}

.exam-db-list {
  margin-top: 10px;
  max-height: 220px;
  overflow-y: auto;
  border-top: 1px dashed #e5e7eb;
  padding-top: 8px;
}

.exam-db-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 6px 0;
  border-bottom: 1px dashed #e5e7eb;
}

/* 过往试卷题库：每道题头部一行 = [勾选框] + [题干] */
.exam-db-item-header {
  display: flex;
  align-items: flex-start;
  gap: 6px;
}

/* 过往试卷题目前面的小方格 */
.exam-db-item-header .past-exam-checkbox {
  margin-top: 2px;
  accent-color: #0ea5e9;  /* 小蓝色方格，和上面知识库一致 */
  cursor: pointer;
}


.exam-db-text {
  font-size: 12px;
  color: #111827;
}

.exam-db-meta-line {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 11px;
  color: #6b7280;
}

.exam-db-delete-btn {
  padding: 2px 8px;
  border-radius: 9999px;
  border: none;
  background: #fee2e2;
  color: #b91c1c;
  font-size: 11px;
  cursor: pointer;
}

.exam-db-delete-btn:hover {
  background: #fecaca;
}


.submit-btn {
  padding: 6px 14px;
  border-radius: 999px;
  border: none;
  font-size: 13px;
  cursor: pointer;
  background: linear-gradient(135deg, #4f46e5, #22c55e);
  color: #ffffff;
  box-shadow: 0 4px 12px rgba(79, 70, 229, 0.25);
  transition: transform 0.12s ease, box-shadow 0.12s ease, opacity 0.12s ease;
}

.submit-btn:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(79, 70, 229, 0.35);
}

.submit-btn:disabled {
  opacity: 0.6;
  box-shadow: none;
  cursor: default;
}

/* 为按钮添加顶部间距 */
/* 为按钮添加顶部间距（Got it / Not clear / Detailed Explanation 共用） */
.understand-btn,
.dont-understand-btn,
.explain-btn {
  margin-top: 20px;  /* 增加按钮顶部的间距 */
  padding: 6px 12px;
  border-radius: 999px;
  border: none;
  font-size: 13px;
  cursor: pointer;
  background: #eef2ff;
  color: #4b5563;
  transition: background-color 0.12s ease, transform 0.12s ease, box-shadow 0.12s ease, opacity 0.12s ease;
}

/* Ask AI 按钮：蓝绿色渐变，与其他按钮风格一致 */
.ask-ai-btn {
  margin-top: 20px;
  padding: 6px 12px;
  border-radius: 999px;
  border: none;
  font-size: 13px;
  cursor: pointer;
  background: linear-gradient(135deg, #38bdf8, #0ea5e9); /* 蓝绿渐变 */
  color: #ffffff;
  transition: background-color 0.12s ease, transform 0.12s ease,
    box-shadow 0.12s ease, opacity 0.12s ease;
}

.ask-ai-btn:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 3px 8px rgba(59, 130, 246, 0.45);
}

.ask-ai-btn:disabled {
  opacity: 0.6;
  cursor: default;
  box-shadow: none;
}



/* ⭐ 为“我理解了 / 我没理解”按钮上色，便于学生快速分辨 */
.understand-btn {
  background: linear-gradient(135deg, #22c55e, #16a34a); /* 绿色渐变 */
  color: #ffffff;
}

.dont-understand-btn {
  background: linear-gradient(135deg, #f97316, #ef4444); /* 橙红色渐变 */
  color: #ffffff;
}


.understand-btn:hover:not(:disabled),
.dont-understand-btn:hover:not(:disabled) {
  background: #e0e7ff;
  transform: translateY(-1px);
  box-shadow: 0 3px 8px rgba(148, 163, 184, 0.35);
}

.understand-btn:disabled,
.dont-understand-btn:disabled {
  opacity: 0.6;
  cursor: default;
  box-shadow: none;
}

/* ⭐ Detailed Explanation 按钮：柔和的黄色渐变 */
.explain-btn {
  background: linear-gradient(135deg, #fde68a, #fbbf24);  /* 柔和黄 → 稍深黄 */
  color: #78350f;                                         /* 深一点的棕色文字，易读 */
}

/* hover 效果：轻微提亮 + 阴影 */
.explain-btn:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 3px 8px rgba(250, 204, 21, 0.45);
}

/* 禁用态 */
.explain-btn:disabled {
  opacity: 0.6;
  cursor: default;
  box-shadow: none;
}

/* 精讲模式文本区域 */
.explain-detail {
  margin-top: 10px;
  padding: 10px 12px;
  border-radius: 10px;
  background: #fef9c3;
  border: 1px dashed #facc15;
  font-size: 13px;
  line-height: 1.5;
  color: #854d0e;
  white-space: pre-wrap;
}

.grade-result {
  flex: 1;
  font-size: 13px;
  color: #374151;
  line-height: 1.4;
  margin-top: 4px;   /* ⭐ 和“提交答案”之间加一点距 */
  white-space: pre-wrap; /* 保留换行，方便显示“结果 + 说明 + 参考答案” */
}


/* 给生成的反馈文字添加底部间距 */
.feedback-line {
  margin: 4px 0;
}

.feedback-result {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 6px;
  background: #eef6ff;
  color: #175cd3;
  font-weight: 700;
}

.feedback-reference {
  margin-top: 8px;
  padding: 8px 10px;
  border-left: 4px solid #16a34a;
  background: #ecfdf3;
  color: #166534;
  font-weight: 650;
}

.feedback-explanation {
  color: #374151;
}

.exam-feedback {
  margin-top: 12px;  /* 为反馈文字添加顶部间距 */
  margin-bottom: 20px; /* 增加反馈文字的底部间距 */
  padding: 10px 12px;
  border-radius: 10px;
  background: #ecfdf5;
  border: 1px solid #bbf7d0;
  font-size: 13px;
  line-height: 1.6;
  color: #166534;
  white-space: pre-wrap;
}

/* 题目导航 + 个性反馈一行显示（你圈的蓝色区域） */
.exam-nav-wrapper {
  margin-top: 12px;
  display: flex;
  align-items: center;
  gap: 10px;
}

/* 中间提示文字撑满一行，左右按钮固定宽度 */
.exam-nav-wrapper .exam-feedback {
  flex: 1;
  margin-top: 0; /* 覆盖上面 .exam-feedback 的 margin-top，让这一行更紧凑 */
}

.bottom-nav-btn {
  width: auto; /* 使按钮宽度根据文字自动调整 */
  height: auto; /* 使按钮高度根据文字自动调整 */
  min-width: 60px; /* 设置最小宽度，避免按钮太小 */
  min-height: 36px; /* 设置最小高度，确保按钮足够大 */
  padding: 8px 16px; /* 增加内边距，确保按钮包裹住文字 */
  font-size: 16px;
  border-radius: 999px;
  border: none;
  background: linear-gradient(135deg, #0ea5e9, #22c55e);
  color: #ffffff;
  display: inline-flex; /* 使用 inline-flex 使按钮根据文字调整大小 */
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: 0 6px 16px rgba(37, 99, 235, 0.35);
  transition: transform 0.12s ease, box-shadow 0.12s ease, opacity 0.12s ease;
}




/* ===== 成绩折线图面板 ===== */

.score-panel {
  margin-top: 12px;
  padding: 10px 12px 14px;
  border-radius: 12px;
  background: #f9fafb;
  border: 1px solid #e5e7eb;
}

.score-panel-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 4px;
}

.score-panel-title {
  font-size: 13px;
  font-weight: 600;
  color: #111827;
}

.score-panel-meta {
  display: flex;
  gap: 10px;
  font-size: 11px;
  color: #6b7280;
}

#score-chart {
  width: 100%;
  height: 180px;
  display: block;
}

/* ===== 向 AI 提问面板 ===== */

.qa-panel {
  margin-top: 12px;
  padding: 10px 12px 12px;
  border-radius: 12px;
  background: #f9fafb;
  border: 1px solid #e5e7eb;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.qa-panel-header {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.qa-panel-title {
  font-size: 14px;
  font-weight: 600;
  color: #111827;
}

.qa-panel-subtitle {
  font-size: 12px;
  color: #6b7280;
  line-height: 1.4;
}

.qa-chat-window {
  margin-top: 6px;
  padding: 8px 10px;
  border-radius: 10px;
  background: #ffffff;
  border: 1px solid #e5e7eb;
  max-height: 220px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.qa-placeholder {
  font-size: 12px;
  color: #9ca3af;
}

/* 聊天气泡 */
.qa-message {
  max-width: 100%;
  padding: 6px 9px;
  border-radius: 10px;
  font-size: 13px;
  line-height: 1.5;
  white-space: pre-wrap;
}

.qa-message.qa-user {
  align-self: flex-end;
  background: #e0f2fe;
  color: #0f172a;
}

.qa-message.qa-assistant {
  align-self: flex-start;
  background: #eef2ff;
  color: #111827;
}

/* === Follow-up: “Extra Practice / Next Question” 按钮 === */
.qa-options-row {
  margin-top: 8px;
  padding: 0;
  background: transparent;        /* 不要气泡背景，只保留按钮 */
  border-radius: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;                       /* 两个按钮之间留一点间距 */
}

/* 基础按钮样式：和 understand-btn 一样的圆角 + 渐变 */
.qa-option-btn {
  padding: 6px 12px;
  border-radius: 999px;
  border: none;
  font-size: 13px;
  cursor: pointer;
  background: linear-gradient(135deg, #22c55e, #16a34a); /* 绿色渐变，和 “Got it” 一致 */
  color: #ffffff;
  box-shadow: 0 3px 8px rgba(34, 197, 94, 0.35);
  transition:
    background-color 0.12s ease,
    transform 0.12s ease,
    box-shadow 0.12s ease,
    opacity 0.12s ease;
}

/* 次级按钮：用和其它导航按钮类似的蓝绿色渐变 */
.qa-option-btn.qa-option-btn-secondary {
  background: linear-gradient(135deg, #0ea5e9, #6366f1);
  box-shadow: 0 3px 8px rgba(37, 99, 235, 0.35);
}

/* hover & disabled 效果 */
.qa-option-btn:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 3px 8px rgba(148, 163, 184, 0.35);
}

.qa-option-btn:disabled {
  opacity: 0.6;
  cursor: default;
  box-shadow: none;
}


/* 输入行稍微留一点间距 */
.qa-input-row {
  margin-top: 6px;
}

/* QA 输入框和按钮的样式，参考出题的 user-input / send-btn */
#qa-input {
  flex: 1;
  min-height: 50px;
  max-height: 120px;
  resize: vertical;
  padding: 8px 10px;
  border-radius: 12px;
  border: 1px solid #d1d5db;
  background: #ffffff;
  font-size: 14px;
  color: #111827;
  outline: none;
}

#qa-input::placeholder {
  color: #9ca3af;
}

#qa-input:focus {
  border-color: #2563eb;
  box-shadow:
    0 0 0 1px #2563eb,
    0 0 0 1px rgba(37, 99, 235, 0.15);
}

#qa-send-btn {
  border: none;
  border-radius: 999px;
  padding: 9px 16px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  color: #ffffff;
  background: linear-gradient(135deg, #6366f1, #0ea5e9);
  box-shadow:
    0 8px 20px rgba(37, 99, 235, 0.25);
  transition: transform 0.1s ease, box-shadow 0.1s ease, opacity 0.15s;
}

#qa-send-btn:hover:enabled {
  transform: translateY(-1px);
  box-shadow:
    0 12px 25px rgba(37, 99, 235, 0.35);
}

#qa-send-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  box-shadow: none;
}

/* ===== 情景迁移练习：全屏弹窗 ===== */
.scenario-modal {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
}

.scenario-modal.hidden {
  display: none;
}

.scenario-modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(15, 23, 42, 0.35);
}

.scenario-modal-dialog {
  position: relative;
  width: min(780px, 96%);
  max-height: 90vh;
  background: #ffffff;
  border-radius: 16px;
  box-shadow: 0 24px 60px rgba(15, 23, 42, 0.35);
  padding: 14px 16px 16px;
  display: flex;
  flex-direction: column;
}

.scenario-modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 6px;
}

.scenario-modal-title {
  font-size: 15px;
  font-weight: 600;
  color: #111827;
}

.scenario-close-btn {
  border: none;
  background: transparent;
  cursor: pointer;
  font-size: 18px;
  line-height: 1;
  padding: 4px;
  color: #6b7280;
}

.scenario-close-btn:hover {
  color: #111827;
}

.scenario-modal-body {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 8px;
  overflow-y: auto;
  padding-right: 4px;
}

.scenario-modal-question {
  padding: 8px 10px;
  border-radius: 10px;
  background: #f9fafb;
  border: 1px solid #e5e7eb;
  font-size: 14px;
  line-height: 1.6;
  color: #111827;
  white-space: pre-wrap;
}

.scenario-modal-answer-block {
  margin-top: 4px;
}

.scenario-modal-actions {
  margin-top: 8px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

/* 让弹窗里的四个按钮高度完全一致（去掉额外的 margin-top） */
.scenario-modal-actions .scenario-submit-btn,
.scenario-modal-actions .scenario-next-btn,
.scenario-modal-actions .understand-btn,
.scenario-modal-actions .dont-understand-btn {
  margin-top: 0;       /* 覆盖全局的 20px */
  padding: 6px 12px;   /* 与左右按钮统一 */
  font-size: 13px;
}


/* “再来一题” 按钮，沿用渐变风格 */
.scenario-next-btn {
  padding: 6px 12px;
  border-radius: 999px;
  border: none;
  cursor: pointer;
  font-size: 13px;
  background: linear-gradient(135deg, #0ea5e9, #22c55e);
  color: #ffffff;
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.35);
  transition: transform 0.12s ease, box-shadow 0.12s ease, opacity 0.12s ease;
}

.scenario-next-btn:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(59, 130, 246, 0.4);
}

.scenario-next-btn:disabled {
  opacity: 0.6;
  box-shadow: none;
  cursor: default;
}

/* 情景题 QA 输入框和按钮样式，参考原来的 QA 面板 */
#scenario-qa-input {
  flex: 1;
  min-height: 50px;
  max-height: 120px;
  resize: vertical;
  padding: 8px 10px;
  border-radius: 12px;
  border: 1px solid #d1d5db;
  background: #ffffff;
  font-size: 14px;
  color: #111827;
  outline: none;
}

#scenario-qa-input::placeholder {
  color: #9ca3af;
}

#scenario-qa-input:focus {
  border-color: #2563eb;
  box-shadow:
    0 0 0 1px #2563eb,
    0 0 0 1px rgba(37, 99, 235, 0.15);
}

#scenario-qa-send-btn {
  border: none;
  border-radius: 999px;
  padding: 9px 16px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  color: #ffffff;
  background: linear-gradient(135deg, #6366f1, #0ea5e9);
  box-shadow:
    0 8px 20px rgba(37, 99, 235, 0.25);
  transition: transform 0.1s ease, box-shadow 0.1s ease, opacity 0.15s;
}

#scenario-qa-send-btn:hover:enabled {
  transform: translateY(-1px);
  box-shadow:
    0 12px 25px rgba(37, 99, 235, 0.35);
}

#scenario-qa-send-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  box-shadow: none;
}


/* ===========================
   📁 文献选择 UI 美化
   =========================== */

.material-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(170px, 1fr));
  gap: 10px;
  margin-top: 10px;
}

.material-list label {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 10px;
  background: #f9fafb;
  border: 1px solid #e5e7eb;
  border-radius: 8px;
  font-size: 13px;
  cursor: pointer;
  transition: 0.18s ease;
}

/* 只对文件名做省略号，让右侧垃圾桶始终可见 */
.material-list .material-name {
  flex: 1;          /* 占满中间这块空间 */
  min-width: 0;     /* 让 text-overflow 生效的关键 */
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}


.material-delete-btn {
  margin-left: auto;
  flex-shrink: 0;
  border: none;
  background: transparent;
  cursor: pointer;
  font-size: 14px;
  padding: 0 2px;
  color: #9ca3af;
}

/* Hover 发光效果 */
.material-list label:hover {
  background: #eefaff;
  border-color: #60a5fa;
  box-shadow: 0 4px 12px rgba(96, 165, 250, 0.25);
}

/* 选中时状态变明显 */
.material-list input:checked + span {
  font-weight: 600;
  color: #0f172a;
}

/* 让 checkbox 和文字分开渲染，这样可控 */
.material-list input[type="checkbox"] {
  accent-color: #0ea5e9;
  cursor: pointer;
}

/* 知识库文件卡片右侧的小垃圾桶按钮 */
.material-delete-btn {
  margin-left: auto;        /* 把垃圾桶挤到最右边 */
  border: none;
  background: transparent;
  cursor: pointer;
  font-size: 14px;
  padding: 0 2px;
  color: #9ca3af;           /* 灰色，默认不太显眼 */
}

.material-delete-btn:hover {
  color: #ef4444;           /* 悬停时变成红色 */
  transform: scale(1.05);
}


:root {
  --ui-btn-bg: linear-gradient(135deg, #22c55e, #0ea5e9, #6366f1);
  --ui-btn-radius: 10px;
  --ui-btn-shadow: 0 8px 18px rgba(56, 189, 248, 0.28);
}

/* Unified button style for question-generation UI */
#send-btn,
#upload-btn,
#past-exam-upload-btn,
.question-nav-btn,
.bottom-nav-btn,
.survey-btn,
.scenario-btn,
.submit-btn,
.understand-btn,
.dont-understand-btn,
.explain-btn,
.ask-ai-btn,
#qa-send-btn,
#scenario-qa-send-btn,
.scenario-submit-btn,
.scenario-next-btn,
.qa-option-btn,
.qa-option-btn.qa-option-btn-secondary,
.small-btn {
  border-radius: var(--ui-btn-radius) !important;
  border: none !important;
  background: var(--ui-btn-bg) !important;
  color: #ffffff !important;
  box-shadow: var(--ui-btn-shadow) !important;
}

#send-btn:hover,
#upload-btn:hover,
#past-exam-upload-btn:hover,
.question-nav-btn:hover,
.bottom-nav-btn:hover,
.survey-btn:hover,
.scenario-btn:hover,
.submit-btn:hover,
.understand-btn:hover,
.dont-understand-btn:hover,
.explain-btn:hover,
.ask-ai-btn:hover,
#qa-send-btn:hover,
#scenario-qa-send-btn:hover,
.scenario-submit-btn:hover,
.scenario-next-btn:hover,
.qa-option-btn:hover,
.small-btn:hover {
  filter: brightness(1.06);
}

#send-btn:disabled,
#upload-btn:disabled,
#past-exam-upload-btn:disabled,
.question-nav-btn:disabled,
.bottom-nav-btn:disabled,
.scenario-btn:disabled,
.submit-btn:disabled,
.understand-btn:disabled,
.dont-understand-btn:disabled,
.explain-btn:disabled,
.ask-ai-btn:disabled,
#qa-send-btn:disabled,
#scenario-qa-send-btn:disabled,
.scenario-submit-btn:disabled,
.scenario-next-btn:disabled,
.qa-option-btn:disabled,
.small-btn:disabled {
  opacity: 0.6;
  box-shadow: none !important;
}

/* Keep delete actions distinguishable */
.material-delete-btn,
.exam-db-delete-btn {
  background: transparent !important;
  color: #ef4444 !important;
  box-shadow: none !important;
  border-radius: 6px !important;
}
/* ===========================
   Button System 2.0 (Exam UI)
   - Unified rounded-rectangle style
   - Consistent cyan/green/indigo theme
   =========================== */
:root {
  --btn-radius: 12px;
  --btn-height: 40px;
  --btn-font-size: 13px;
  --btn-font-weight: 600;

  --btn-primary-bg: linear-gradient(135deg, #22c55e 0%, #0ea5e9 55%, #6366f1 100%);
  --btn-primary-shadow: 0 8px 20px rgba(14, 165, 233, 0.28);

  --btn-secondary-bg: linear-gradient(135deg, #0ea5e9 0%, #2563eb 100%);
  --btn-secondary-shadow: 0 8px 18px rgba(37, 99, 235, 0.26);

  --btn-neutral-bg: #f8fafc;
  --btn-neutral-text: #334155;
  --btn-neutral-border: #cbd5e1;

  --btn-danger-bg: #fef2f2;
  --btn-danger-text: #b91c1c;
  --btn-danger-border: #fecaca;
}

/* Common button shape */
#send-btn,
#upload-btn,
#past-exam-upload-btn,
.submit-btn,
.understand-btn,
.dont-understand-btn,
.explain-btn,
.ask-ai-btn,
#qa-send-btn,
#scenario-qa-send-btn,
.scenario-submit-btn,
.scenario-next-btn,
.scenario-btn,
.question-nav-btn,
.bottom-nav-btn,
.survey-btn,
.qa-option-btn,
.qa-option-btn.qa-option-btn-secondary,
.small-btn,
.logout-btn {
  border-radius: var(--btn-radius) !important;
  border: none !important;
  min-height: var(--btn-height);
  padding: 8px 14px !important;
  font-size: var(--btn-font-size) !important;
  font-weight: var(--btn-font-weight) !important;
  line-height: 1;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: transform 0.12s ease, box-shadow 0.12s ease, filter 0.12s ease, opacity 0.12s ease;
}

/* Primary themed actions */
#send-btn,
#upload-btn,
#past-exam-upload-btn,
.submit-btn,
#qa-send-btn,
#scenario-qa-send-btn,
.scenario-submit-btn,
.ask-ai-btn,
.scenario-btn,
.survey-btn,
.logout-btn {
  background: var(--btn-primary-bg) !important;
  color: #ffffff !important;
  box-shadow: var(--btn-primary-shadow) !important;
}

/* Secondary themed actions */
.understand-btn,
.dont-understand-btn,
.explain-btn,
.scenario-next-btn,
.question-nav-btn,
.bottom-nav-btn,
.qa-option-btn,
.qa-option-btn.qa-option-btn-secondary {
  background: var(--btn-secondary-bg) !important;
  color: #ffffff !important;
  box-shadow: var(--btn-secondary-shadow) !important;
}

/* Neutral utility actions */
.small-btn {
  background: var(--btn-neutral-bg) !important;
  color: var(--btn-neutral-text) !important;
  border: 1px solid var(--btn-neutral-border) !important;
  box-shadow: none !important;
}

/* Make nav buttons rectangular (not circles) */
.question-nav-btn,
.bottom-nav-btn {
  width: auto !important;
  min-width: 116px !important;
  height: var(--btn-height) !important;
}

/* Hover / active / disabled */
#send-btn:hover,
#upload-btn:hover,
#past-exam-upload-btn:hover,
.submit-btn:hover,
.understand-btn:hover,
.dont-understand-btn:hover,
.explain-btn:hover,
.ask-ai-btn:hover,
#qa-send-btn:hover,
#scenario-qa-send-btn:hover,
.scenario-submit-btn:hover,
.scenario-next-btn:hover,
.scenario-btn:hover,
.question-nav-btn:hover,
.bottom-nav-btn:hover,
.survey-btn:hover,
.qa-option-btn:hover,
.small-btn:hover,
.logout-btn:hover {
  transform: translateY(-1px);
  filter: brightness(1.05);
}

#send-btn:active,
#upload-btn:active,
#past-exam-upload-btn:active,
.submit-btn:active,
.understand-btn:active,
.dont-understand-btn:active,
.explain-btn:active,
.ask-ai-btn:active,
#qa-send-btn:active,
#scenario-qa-send-btn:active,
.scenario-submit-btn:active,
.scenario-next-btn:active,
.scenario-btn:active,
.question-nav-btn:active,
.bottom-nav-btn:active,
.survey-btn:active,
.qa-option-btn:active,
.small-btn:active,
.logout-btn:active {
  transform: translateY(0);
}

#send-btn:disabled,
#upload-btn:disabled,
#past-exam-upload-btn:disabled,
.submit-btn:disabled,
.understand-btn:disabled,
.dont-understand-btn:disabled,
.explain-btn:disabled,
.ask-ai-btn:disabled,
#qa-send-btn:disabled,
#scenario-qa-send-btn:disabled,
.scenario-submit-btn:disabled,
.scenario-next-btn:disabled,
.scenario-btn:disabled,
.question-nav-btn:disabled,
.bottom-nav-btn:disabled,
.survey-btn:disabled,
.qa-option-btn:disabled,
.small-btn:disabled,
.logout-btn:disabled {
  opacity: 0.55;
  cursor: not-allowed;
  box-shadow: none !important;
  transform: none;
}

/* Keep delete-style actions clearly dangerous */
.material-delete-btn,
.exam-db-delete-btn {
  border-radius: 8px !important;
  border: 1px solid var(--btn-danger-border) !important;
  background: var(--btn-danger-bg) !important;
  color: var(--btn-danger-text) !important;
  box-shadow: none !important;
  min-height: 30px;
  padding: 4px 8px !important;
}

.material-delete-btn:hover,
.exam-db-delete-btn:hover {
  filter: brightness(0.98);
}

.topbar-right {
  display: inline-flex;
  align-items: center;
  justify-content: flex-end;
  gap: 12px;
  margin-left: auto;
}

.lang-toggle-btn {
  min-width: 66px;
  height: 34px;
  border-radius: 10px !important;
}

.guest-login-btn {
  min-width: 74px;
  height: 34px;
  border-radius: 10px !important;
  background: linear-gradient(135deg, #0ea5e9 0%, #14b8a6 55%, #22c55e 100%) !important;
  color: #ffffff !important;
  box-shadow: 0 8px 16px rgba(14, 165, 233, 0.22) !important;
}
/* ===========================
   Layout Fix: Last/Next same baseline
   =========================== */
.exam-nav-wrapper {
  display: grid !important;
  grid-template-columns: auto 1fr auto;
  align-items: start !important;
  column-gap: 12px;
}

.exam-nav-center {
  align-items: stretch !important;
}

/* Keep Last and Next on the exact same horizontal line */
#exam-prev-btn,
#exam-next-btn {
  margin-top: 0 !important;
  align-self: start;
  min-width: 132px !important;
  height: 40px !important;
}

.exam-nav-right {
  align-items: flex-end !important;
  justify-content: flex-start;
  gap: 8px;
}

/* Prevent questionnaire button from pushing Next button down visually */
.survey-btn {
  margin-top: 0 !important;
  min-width: 132px;
  height: 40px;
}

/* ===========================
   Material List Unified Format
   =========================== */
.material-list-box {
  margin-top: 10px;
  padding: 10px;
  border: 1px solid #e5e7eb;
  border-radius: 12px;
  background: #f8fafc;
}

.material-list-title {
  font-size: 13px;
  font-weight: 600;
  color: #0f172a;
  margin-bottom: 8px;
}

.material-list {
  display: flex !important;
  flex-direction: column;
  gap: 8px;
  max-height: 220px;
  overflow-y: auto;
  padding-right: 2px;
}

.material-item {
  display: grid !important;
  grid-template-columns: 20px 1fr auto;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  border-radius: 10px;
  border: 1px solid #dbe4ef;
  background: #ffffff;
  transition: border-color 0.12s ease, box-shadow 0.12s ease, background 0.12s ease;
}

.material-item:hover {
  border-color: #93c5fd;
  box-shadow: 0 4px 10px rgba(14, 165, 233, 0.15);
  background: #f8fdff;
}

.material-checkbox {
  width: 16px;
  height: 16px;
  margin: 0;
  accent-color: #0ea5e9;
}

.material-name {
  min-width: 0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  font-size: 13px;
  color: #1f2937;
}

.material-list-actions {
  display: flex;
  gap: 8px;
  margin-top: 10px;
}

.material-list-actions .small-btn {
  min-width: 92px;
  height: 36px;
  border-radius: 10px !important;
}
/* ===========================
   Button Theme 3.0 - Fresh Light UI
   =========================== */
:root {
  --btn-radius-3: 12px;
  --btn-h-3: 40px;
  --btn-font-3: 13px;
  --btn-weight-3: 600;

  --btn-primary-grad: linear-gradient(135deg, #0ea5e9 0%, #14b8a6 55%, #22c55e 100%);
  --btn-primary-shadow: 0 10px 20px rgba(20, 184, 166, 0.28);

  --btn-accent-grad: linear-gradient(135deg, #38bdf8 0%, #06b6d4 100%);
  --btn-accent-shadow: 0 8px 16px rgba(14, 165, 233, 0.25);

  --btn-surface-bg: #f8fafc;
  --btn-surface-border: #cbd5e1;
  --btn-surface-text: #334155;

  --btn-success-grad: linear-gradient(135deg, #22c55e 0%, #16a34a 100%);
  --btn-success-shadow: 0 8px 16px rgba(34, 197, 94, 0.25);

  --btn-warning-grad: linear-gradient(135deg, #f59e0b 0%, #f97316 100%);
  --btn-warning-shadow: 0 8px 16px rgba(249, 115, 22, 0.25);

  --btn-danger-bg-3: #fef2f2;
  --btn-danger-border-3: #fecaca;
  --btn-danger-text-3: #b91c1c;
}

/* Base shape */
#send-btn,
#upload-btn,
#past-exam-upload-btn,
.submit-btn,
#qa-send-btn,
#scenario-qa-send-btn,
.scenario-submit-btn,
.scenario-btn,
.survey-btn,
.logout-btn,
.question-nav-btn,
.bottom-nav-btn,
.scenario-next-btn,
.ask-ai-btn,
.explain-btn,
.understand-btn,
.dont-understand-btn,
.qa-option-btn,
.small-btn,
.auth-submit-btn,
.auth-tab-btn {
  border-radius: var(--btn-radius-3) !important;
  min-height: var(--btn-h-3);
  padding: 8px 14px !important;
  font-size: var(--btn-font-3) !important;
  font-weight: var(--btn-weight-3) !important;
  border: none;
  transition: transform 0.12s ease, box-shadow 0.12s ease, filter 0.12s ease, opacity 0.12s ease;
}

/* Primary CTAs */
#send-btn,
#upload-btn,
#past-exam-upload-btn,
.submit-btn,
#qa-send-btn,
#scenario-qa-send-btn,
.scenario-submit-btn,
.auth-submit-btn {
  background: var(--btn-primary-grad) !important;
  color: #fff !important;
  box-shadow: var(--btn-primary-shadow) !important;
}

/* Accent actions */
.scenario-btn,
.survey-btn,
.ask-ai-btn,
.qa-option-btn,
.logout-btn {
  background: var(--btn-accent-grad) !important;
  color: #fff !important;
  box-shadow: var(--btn-accent-shadow) !important;
}

/* Positive confirmation */
.understand-btn {
  background: var(--btn-success-grad) !important;
  color: #fff !important;
  box-shadow: var(--btn-success-shadow) !important;
}

/* Warning / attention */
.dont-understand-btn {
  background: var(--btn-warning-grad) !important;
  color: #fff !important;
  box-shadow: var(--btn-warning-shadow) !important;
}

/* Secondary neutral controls */
.question-nav-btn,
.bottom-nav-btn,
.scenario-next-btn,
.explain-btn,
.small-btn,
.auth-tab-btn {
  background: var(--btn-surface-bg) !important;
  color: var(--btn-surface-text) !important;
  border: 1px solid var(--btn-surface-border) !important;
  box-shadow: 0 2px 6px rgba(15, 23, 42, 0.08) !important;
}

/* Active auth tab = themed */
.auth-tab-btn.active {
  background: var(--btn-primary-grad) !important;
  color: #fff !important;
  border: none !important;
  box-shadow: var(--btn-primary-shadow) !important;
}

/* Danger actions remain explicit */
.material-delete-btn,
.exam-db-delete-btn {
  background: var(--btn-danger-bg-3) !important;
  border: 1px solid var(--btn-danger-border-3) !important;
  color: var(--btn-danger-text-3) !important;
  border-radius: 8px !important;
  box-shadow: none !important;
}

/* Interactions */
#send-btn:hover,
#upload-btn:hover,
#past-exam-upload-btn:hover,
.submit-btn:hover,
#qa-send-btn:hover,
#scenario-qa-send-btn:hover,
.scenario-submit-btn:hover,
.scenario-btn:hover,
.survey-btn:hover,
.logout-btn:hover,
.question-nav-btn:hover,
.bottom-nav-btn:hover,
.scenario-next-btn:hover,
.ask-ai-btn:hover,
.explain-btn:hover,
.understand-btn:hover,
.dont-understand-btn:hover,
.qa-option-btn:hover,
.small-btn:hover,
.auth-submit-btn:hover,
.auth-tab-btn:hover {
  transform: translateY(-1px);
  filter: brightness(1.04);
}

#send-btn:disabled,
#upload-btn:disabled,
#past-exam-upload-btn:disabled,
.submit-btn:disabled,
#qa-send-btn:disabled,
#scenario-qa-send-btn:disabled,
.scenario-submit-btn:disabled,
.scenario-btn:disabled,
.survey-btn:disabled,
.logout-btn:disabled,
.question-nav-btn:disabled,
.bottom-nav-btn:disabled,
.scenario-next-btn:disabled,
.ask-ai-btn:disabled,
.explain-btn:disabled,
.understand-btn:disabled,
.dont-understand-btn:disabled,
.qa-option-btn:disabled,
.small-btn:disabled,
.auth-submit-btn:disabled,
.auth-tab-btn:disabled {
  opacity: 0.58;
  box-shadow: none !important;
  transform: none;
}

/* ===== Exercise Agent auth screen ===== */
body.auth-open {
  min-height: 100vh;
  overflow: hidden;
}

.hidden,
.app-hidden {
  display: none !important;
}

.auth-screen {
  position: fixed;
  inset: 0;
  z-index: 3000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 92px 48px 28px;
  overflow-y: auto;
  background:
    radial-gradient(circle at 18% 14%, rgba(14, 165, 233, 0.12), transparent 28%),
    radial-gradient(circle at 82% 76%, rgba(34, 197, 94, 0.1), transparent 32%),
    linear-gradient(135deg, #f8fafc 0%, #f0fdfa 48%, #eff6ff 100%);
}

.auth-topbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 3;
  min-height: 62px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 24px;
  background: rgba(255, 255, 255, 0.94);
  border-bottom: 1px solid #e5e7eb;
  backdrop-filter: blur(12px);
  box-shadow: 0 8px 22px rgba(15, 23, 42, 0.04);
}

.auth-screen::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(circle at 18% 18%, rgba(14, 165, 233, 0.12), transparent 28%),
    radial-gradient(circle at 82% 78%, rgba(34, 197, 94, 0.12), transparent 30%),
    linear-gradient(rgba(148, 163, 184, 0.1) 1px, transparent 1px);
  background-size: auto, auto, 100% 28px;
}

.auth-shell {
  position: relative;
  z-index: 1;
  width: min(1440px, 100%);
  min-height: min(800px, calc(100vh - 120px));
  display: grid;
  grid-template-columns: minmax(480px, 1.12fr) minmax(420px, 0.95fr);
  gap: 30px;
}

.auth-footer-credit {
  position: fixed;
  left: 50%;
  bottom: 12px;
  z-index: 2;
  transform: translateX(-50%);
  color: #64748b;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.04em;
  text-align: center;
  white-space: nowrap;
}

.auth-visual,
.auth-card {
  border-radius: 22px;
  overflow: hidden;
}

.auth-visual {
  position: relative;
  padding: 44px 48px 48px;
  color: #f8fafc;
  background:
    linear-gradient(rgba(248, 250, 252, 0.34), rgba(248, 250, 252, 0.34)),
    url("/static/auth-ai-tutor-bg.png") center / cover no-repeat;
  border: 1px solid rgba(226, 232, 240, 0.42);
  box-shadow: 0 24px 60px rgba(15, 23, 42, 0.16);
}

.auth-visual-content {
  height: 100%;
  display: flex;
  flex-direction: column;
}

.auth-kicker,
.auth-badge {
  width: max-content;
  border: 1px solid rgba(186, 230, 253, 0.55);
  border-radius: 10px;
  padding: 8px 13px;
  font-size: 12px;
  letter-spacing: 0.09em;
  font-weight: 700;
  background: rgba(15, 23, 42, 0.22);
  backdrop-filter: blur(8px);
}

.auth-badge {
  color: #0369a1;
  background: #eff6ff;
  border-color: #bae6fd;
  margin-bottom: 22px;
}

.auth-copy h1 {
  max-width: 620px;
  margin: 34px 0 16px;
  font-size: clamp(42px, 4vw, 72px);
  line-height: 1.02;
  letter-spacing: 0;
  color: #f8fafc;
  text-shadow: 0 4px 18px rgba(15, 23, 42, 0.45);
}

html:lang(zh-CN) .auth-copy h1 {
  max-width: 560px;
  font-size: clamp(40px, 3.7vw, 64px);
}

.auth-copy p {
  max-width: 620px;
  margin: 0;
  color: rgba(248, 250, 252, 0.9);
  font-size: 18px;
  line-height: 1.7;
  text-shadow: 0 2px 10px rgba(15, 23, 42, 0.35);
}

.auth-benefits {
  margin-top: auto;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.auth-benefits div {
  min-height: 124px;
  padding: 22px 20px;
  border: 1px solid rgba(226, 232, 240, 0.38);
  border-radius: 12px;
  background: rgba(15, 23, 42, 0.28);
  backdrop-filter: blur(12px);
  transition: transform 0.16s ease, box-shadow 0.16s ease, background 0.16s ease;
}

.auth-benefits div:hover {
  transform: translateY(-3px) scale(1.012);
  background: rgba(15, 23, 42, 0.34);
  box-shadow: 0 12px 26px rgba(15, 23, 42, 0.18);
}

.auth-benefits strong {
  display: block;
  margin-bottom: 12px;
  font-size: 16px;
}

.auth-benefits span {
  display: block;
  color: rgba(248, 250, 252, 0.82);
  line-height: 1.6;
}

.auth-card {
  padding: 14px;
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid #e5e7eb;
  box-shadow:
    0 24px 60px rgba(15, 23, 42, 0.1),
    0 0 0 1px rgba(15, 23, 42, 0.02);
}

.auth-card-inner {
  min-height: 100%;
  padding: clamp(30px, 4vw, 58px) clamp(26px, 4vw, 38px);
  border-radius: 14px;
  border: 1px solid #e5e7eb;
  background: rgba(249, 250, 251, 0.72);
}

.auth-form h2 {
  margin: 0 0 10px;
  max-width: 560px;
  font-size: clamp(30px, 2.6vw, 38px);
  line-height: 1.12;
  color: #0f172a;
  letter-spacing: 0;
}

html:lang(zh-CN) .auth-form h2 {
  font-size: clamp(30px, 2.4vw, 36px);
}

.auth-form p {
  margin: 0 0 32px;
  color: #64748b;
  font-size: 17px;
  line-height: 1.7;
}

.auth-form label {
  display: flex;
  flex-direction: column;
  gap: 9px;
  margin-bottom: 22px;
  color: #0f172a;
  font-weight: 700;
}

#login-form label {
  gap: 7px;
  margin-bottom: 18px;
}

.auth-form label > span {
  color: #64748b;
  font-weight: 400;
  line-height: 1.55;
}

.auth-form input[type="text"],
.auth-form input[type="email"],
.auth-form input[type="password"] {
  width: 100%;
  min-height: 54px;
  border-radius: 12px;
  border: 1px solid #d1d5db;
  background: #ffffff;
  padding: 0 17px;
  font: inherit;
  font-size: 16px;
  color: #111827;
  outline: none;
}

.auth-form input:focus {
  border-color: #0ea5e9;
  box-shadow:
    0 0 0 1px #0ea5e9,
    0 0 0 4px rgba(14, 165, 233, 0.12);
}

.auth-two {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.auth-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 18px;
}

.auth-check {
  flex-direction: row !important;
  align-items: center;
  gap: 10px !important;
  margin: 0 !important;
  color: #64748b !important;
  font-weight: 500 !important;
}

.auth-check input {
  width: 14px;
  height: 14px;
  accent-color: #0ea5e9;
}

.auth-link,
.auth-switch button {
  border: none;
  background: transparent;
  padding: 0;
  color: #0284c7;
  font: inherit;
  font-weight: 700;
  cursor: pointer;
  transition: color 0.15s ease, transform 0.15s ease;
}

.auth-link:hover,
.auth-switch button:hover {
  color: #0ea5e9;
  transform: translateY(-1px) scale(1.035);
}

.auth-link:active,
.auth-switch button:active {
  transform: translateY(0) scale(0.98);
}

.auth-primary,
.auth-guest {
  width: 100%;
  min-height: 58px;
  border-radius: 12px;
  border: none;
  cursor: pointer;
  font-size: 17px;
  font-weight: 800;
  transform: translateZ(0);
  transition: transform 0.16s ease, box-shadow 0.16s ease, filter 0.16s ease;
}

.auth-primary {
  color: #ffffff;
  background: linear-gradient(135deg, #0ea5e9 0%, #14b8a6 55%, #22c55e 100%);
  box-shadow: 0 10px 20px rgba(20, 184, 166, 0.28);
}

.auth-primary.gold,
.auth-guest {
  color: #ffffff;
  background: linear-gradient(135deg, #38bdf8 0%, #06b6d4 100%);
  border: none;
  box-shadow: 0 8px 16px rgba(14, 165, 233, 0.25);
}

.auth-primary:hover,
.auth-guest:hover {
  transform: translateY(-2px) scale(1.018);
  filter: brightness(1.05);
  box-shadow: 0 14px 28px rgba(20, 184, 166, 0.34);
}

.auth-primary:active,
.auth-guest:active {
  transform: translateY(0) scale(0.99);
  filter: brightness(0.98);
}

.auth-primary:disabled,
.auth-guest:disabled {
  cursor: not-allowed;
  opacity: 0.62;
  transform: none;
  box-shadow: none;
}

.auth-guest {
  margin-top: 42px;
}

.auth-switch {
  margin-top: 24px;
  color: #64748b;
  text-align: center;
}

.auth-message {
  min-height: 22px;
  margin: -4px 0 10px;
  color: #b91c1c;
  font-size: 14px;
}

.auth-message.success {
  color: #16a34a;
}

.account-chip {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: #374151;
  font-size: 13px;
  padding: 4px 8px 4px 4px;
  border-radius: 999px;
  white-space: nowrap;
  order: 10;
  cursor: pointer;
  transition: transform 0.16s ease, background 0.16s ease, box-shadow 0.16s ease;
}

.account-chip:hover,
.account-chip:focus-visible {
  transform: translateY(-1px);
  background: #f0f9ff;
  box-shadow: 0 10px 22px rgba(14, 165, 233, 0.14);
  outline: none;
}

.account-chip:hover .account-avatar,
.account-chip:focus-visible .account-avatar {
  transform: scale(1.08);
  box-shadow: 0 12px 24px rgba(14, 165, 233, 0.32);
}

.account-avatar {
  width: 34px;
  height: 34px;
  border-radius: 999px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: #ffffff;
  font-weight: 800;
  text-transform: uppercase;
  background: linear-gradient(135deg, #0ea5e9 0%, #14b8a6 55%, #22c55e 100%);
  box-shadow: 0 8px 18px rgba(14, 165, 233, 0.24);
  transition: transform 0.16s ease, box-shadow 0.16s ease;
}

.account-chip #account-name {
  font-weight: 700;
  color: #0284c7;
}

.account-chip .logout-btn {
  min-height: 34px;
  padding: 7px 12px !important;
}

.auth-lang-toggle-btn {
  min-width: 72px;
  height: 38px;
  border-radius: 12px !important;
  background: #ffffff !important;
  color: #334155 !important;
  border: 1px solid #cbd5e1 !important;
  box-shadow: 0 8px 18px rgba(15, 23, 42, 0.08) !important;
}

body.auth-register .auth-copy-login,
body:not(.auth-register) .auth-copy-register {
  display: none;
}

@media (max-width: 980px) {
  body.auth-open {
    overflow: auto;
  }

  .auth-screen {
    align-items: flex-start;
    padding: 88px 18px 18px;
  }

  .auth-shell {
    min-height: auto;
    grid-template-columns: 1fr;
  }

  .auth-visual {
    min-height: 430px;
    padding: 30px;
  }

  .auth-copy h1 {
    max-width: 560px;
    font-size: clamp(38px, 8vw, 58px);
  }

  .auth-benefits {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .auth-screen {
    padding: 78px 0 0;
  }

  .auth-lang-toggle-btn {
    min-width: 64px;
  }

  .auth-shell {
    gap: 0;
  }

  .auth-visual,
  .auth-card {
    border-radius: 0;
  }

  .auth-card {
    padding: 10px;
  }

  .auth-copy h1 {
    font-size: 36px;
    line-height: 1.08;
  }

  .auth-form h2 {
    font-size: 28px;
  }

  .auth-two {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .auth-row {
    align-items: flex-start;
    flex-direction: column;
  }
}

/* ===========================
   Polished upload and material panels
   =========================== */
.right-panel {
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.96), rgba(248, 250, 252, 0.96)) !important;
}

.bordered-box,
.exam-db-box,
.score-panel,
.tip-box {
  border-radius: 14px !important;
  border: 1px solid #dbe4ef !important;
  background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%) !important;
  box-shadow: 0 10px 22px rgba(15, 23, 42, 0.045) !important;
}

.bordered-box,
.exam-db-box {
  padding: 16px !important;
}

.right-panel h2,
.exam-db-title,
.score-panel-title,
.tip-title,
.material-list-title {
  color: #0f172a !important;
  font-weight: 800 !important;
}

.hint {
  color: #64748b !important;
  line-height: 1.45;
}

.upload-box {
  gap: 10px !important;
  margin-bottom: 12px !important;
}

.file-picker {
  display: block;
  width: max-content;
  max-width: 100%;
}

.file-picker:hover {
  transform: none;
  box-shadow: none;
}

#file-input,
#past-exam-file-input {
  max-width: 100%;
  font-size: 13px !important;
  color: #475569 !important;
  cursor: pointer;
}

#file-input::file-selector-button,
#past-exam-file-input::file-selector-button {
  min-height: 30px;
  margin-right: 10px;
  padding: 6px 12px;
  border-radius: 8px;
  border: 1px solid #cbd5e1;
  background: #ffffff;
  color: #334155;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 2px 6px rgba(15, 23, 42, 0.08);
  transition: border-color 0.14s ease, color 0.14s ease, transform 0.14s ease;
}

#file-input::file-selector-button:hover,
#past-exam-file-input::file-selector-button:hover {
  color: #0284c7;
  border-color: #7dd3fc;
  transform: translateY(-1px);
}

.material-list-box {
  border-radius: 14px !important;
  border: 1px solid #dbe4ef !important;
  background: #ffffff !important;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.85);
}

.material-item {
  min-height: 48px;
  border: 1px solid #dbe4ef !important;
  background: linear-gradient(180deg, #ffffff, #f8fafc) !important;
  box-shadow: 0 4px 12px rgba(15, 23, 42, 0.035);
}

.material-item:hover {
  transform: translateY(-1px);
  border-color: #7dd3fc !important;
  box-shadow: 0 8px 18px rgba(14, 165, 233, 0.14) !important;
}

.material-name {
  font-weight: 700;
  color: #0f172a !important;
}

.material-delete-btn {
  width: 34px;
  height: 34px;
  min-height: 34px !important;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 !important;
  border-radius: 10px !important;
  border: 1px solid #fecaca !important;
  background: #fff7f7 !important;
  color: #ef4444 !important;
  box-shadow: none !important;
}

.material-delete-btn svg {
  width: 17px;
  height: 17px;
  stroke: currentColor;
  stroke-width: 2;
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.material-delete-btn:hover {
  transform: translateY(-1px) scale(1.04);
  border-color: #fca5a5 !important;
  background: #fef2f2 !important;
  color: #dc2626 !important;
}

.material-list-actions .small-btn {
  min-width: 104px !important;
  border-radius: 10px !important;
}

/* ===========================
   Question card and Ask AI polish
   =========================== */
.chat-window {
  min-height: 500px !important;
  max-height: none !important;
  overflow-y: auto;
}

.question-card {
  min-height: 500px !important;
  max-height: none !important;
  overflow: visible;
  border-radius: 18px !important;
}

.question-card-body {
  min-height: 150px;
}

/* Generated questions should follow their content instead of reserving a
   fixed 500px canvas. This keeps the question navigation in view while still
   allowing long questions and explanations to grow naturally. */
.chat-window.question-layout-active {
  flex: 0 0 auto;
  min-height: 0 !important;
  max-height: none !important;
  overflow-y: visible;
}

.chat-window.question-layout-active .question-card-wrapper {
  flex: 0 0 auto;
  align-items: flex-start;
}

.chat-window.question-layout-active .question-card {
  min-height: 0 !important;
  max-height: none !important;
}

.chat-window.question-layout-active .question-card-body {
  flex: 0 0 auto;
  min-height: 0;
  overflow-y: visible;
}

.question-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
}

.question-card-title {
  min-width: 0;
}

.completion-back-btn {
  flex: 0 0 auto;
  min-height: 38px;
  padding: 0 14px;
  border: 1px solid #99f6e4;
  border-radius: 10px;
  background: #ecfeff;
  color: #115e59;
  font-size: 13px;
  font-weight: 800;
  cursor: pointer;
  transition: transform 0.15s ease, background 0.15s ease, border-color 0.15s ease;
}

.completion-back-btn:hover {
  transform: translateY(-1px);
  background: #ccfbf1;
  border-color: #5eead4;
}

.completion-overview {
  min-height: 500px;
  display: flex;
  flex-direction: column;
  gap: 18px;
  padding: 20px;
  border: 1px solid #dbe4ef;
  border-radius: 18px;
  background: #ffffff;
  box-shadow: 0 12px 28px rgba(15, 23, 42, 0.07);
}

.completion-overview-header {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.completion-overview-title {
  margin: 0;
  color: #0f172a;
  font-size: 22px;
  font-weight: 800;
  letter-spacing: 0;
}

.completion-overview-subtitle {
  margin: 0;
  color: #64748b;
  font-size: 14px;
  line-height: 1.6;
}

.completion-question-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  max-height: 380px;
  overflow-y: auto;
  padding-right: 4px;
}

.completion-analysis-toolbar {
  display: flex;
  justify-content: flex-start;
}

.completion-analyze-btn {
  min-height: 42px;
  padding: 0 18px;
  border: none;
  border-radius: 11px;
  background: #2563eb;
  color: #ffffff;
  font-size: 14px;
  font-weight: 800;
  cursor: pointer;
  box-shadow: 0 12px 22px rgba(37, 99, 235, 0.18);
  transition: transform 0.15s ease, background 0.15s ease, opacity 0.15s ease;
}

.completion-analyze-btn:hover:not(:disabled) {
  transform: translateY(-1px);
  background: #1d4ed8;
}

.completion-analyze-btn:disabled {
  opacity: 0.72;
  cursor: wait;
}

.completion-analysis-panel {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 16px;
  border: 1px solid #dbeafe;
  border-radius: 14px;
  background: #eff6ff;
}

.completion-analysis-title {
  margin: 0;
  color: #1e3a8a;
  font-size: 15px;
  font-weight: 800;
  letter-spacing: 0;
}

.completion-analysis-content {
  color: #1e293b;
  font-size: 14px;
  line-height: 1.8;
  white-space: pre-wrap;
}

.completion-question-row {
  min-height: 60px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 16px;
  padding: 12px 14px;
  border: 1px solid #e2e8f0;
  border-radius: 12px;
  background: #f8fafc;
}

.completion-question-label {
  color: #0f172a;
  font-size: 15px;
  font-weight: 700;
}

.completion-question-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.completion-status-pill {
  min-width: 72px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 10px;
  border-radius: 999px;
  background: #dcfce7;
  color: #166534;
  font-size: 13px;
  font-weight: 800;
}

.completion-review-btn {
  min-width: 84px;
  min-height: 38px;
  border: none;
  border-radius: 10px;
  background: #0f766e;
  color: #ffffff;
  font-size: 14px;
  font-weight: 800;
  cursor: pointer;
  transition: transform 0.15s ease, background 0.15s ease, box-shadow 0.15s ease;
}

.completion-review-btn:hover {
  transform: translateY(-1px);
  background: #115e59;
  box-shadow: 0 10px 20px rgba(15, 118, 110, 0.18);
}

@media (max-width: 720px) {
  .question-card-header {
    align-items: stretch;
    flex-direction: column;
  }

  .completion-back-btn {
    width: 100%;
  }

  .completion-question-row {
    grid-template-columns: 1fr;
    align-items: stretch;
  }

  .completion-question-actions {
    justify-content: space-between;
  }
}

.qa-panel {
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
  overflow: hidden;
  margin-top: 14px !important;
  padding: 14px !important;
  border-radius: 16px !important;
  border: 1px solid #dbe4ef !important;
  background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%) !important;
  box-shadow: 0 8px 18px rgba(15, 23, 42, 0.045);
}

.understand-row {
  width: 100%;
}

.question-scenario-btn {
  margin-left: auto;
  min-height: 38px;
  padding: 0 14px;
  border-radius: 12px;
  align-self: center;
  white-space: nowrap;
}

.understand-row .question-scenario-btn,
button#scenario-entry-btn.question-scenario-btn {
  width: auto !important;
  min-width: 188px !important;
  max-width: none !important;
  min-height: 40px !important;
  padding: 8px 16px !important;
  display: inline-flex !important;
  align-items: center !important;
  justify-content: center !important;
  overflow: visible !important;
  white-space: nowrap !important;
  color: #ffffff !important;
  font-size: 13px !important;
  line-height: 1 !important;
  text-indent: 0 !important;
}

.understand-row .question-scenario-btn:disabled,
button#scenario-entry-btn.question-scenario-btn:disabled {
  min-width: 188px !important;
}

.qa-panel-header {
  gap: 4px !important;
  padding-bottom: 8px;
  border-bottom: 1px solid #edf2f7;
}

.qa-panel-title {
  color: #0f172a !important;
  font-size: 15px !important;
  font-weight: 800 !important;
}

.qa-panel-subtitle {
  color: #64748b !important;
  font-size: 12px !important;
}

.qa-chat-window {
  width: 100%;
  box-sizing: border-box;
  max-height: 150px !important;
  margin-top: 8px !important;
  padding: 10px !important;
  border-radius: 14px !important;
  border: 1px solid #e2e8f0 !important;
  background: #ffffff !important;
}

.qa-message {
  max-width: min(78%, 760px) !important;
  border-radius: 12px !important;
}

.qa-message.qa-user {
  background: #dcfce7 !important;
}

.qa-message.qa-assistant,
.qa-placeholder {
  background: #eef2ff;
  color: #334155 !important;
}

.qa-placeholder {
  width: max-content;
  max-width: 82%;
  padding: 7px 10px;
  border-radius: 12px;
  font-size: 13px !important;
}

.qa-input-row {
  width: 100%;
  display: grid !important;
  grid-template-columns: minmax(0, 1fr) 48px;
  align-items: end;
  gap: 10px !important;
  margin-top: 10px !important;
}

#qa-input {
  width: 100%;
  min-width: 0;
  min-height: 54px !important;
  max-height: 92px !important;
  border-radius: 14px !important;
  border: 1px solid #cbd5e1 !important;
  box-sizing: border-box;
}

#qa-input:focus {
  border-color: #0ea5e9 !important;
  box-shadow: 0 0 0 3px rgba(14, 165, 233, 0.15) !important;
}

#qa-send-btn,
#scenario-qa-send-btn {
  width: 48px !important;
  min-width: 48px !important;
  height: 48px !important;
  padding: 0 !important;
  border-radius: 14px !important;
  position: relative;
  white-space: nowrap;
  overflow: hidden;
}

#qa-send-btn.qa-send-loading::before,
#scenario-qa-send-btn.qa-send-loading::before {
  content: "";
  width: 18px;
  height: 18px;
  border: 3px solid rgba(255, 255, 255, 0.55);
  border-top-color: #ffffff;
  border-radius: 999px;
  animation: qa-send-spin 0.7s linear infinite;
}

@keyframes qa-send-spin {
  to {
    transform: rotate(360deg);
  }
}

.exam-nav-wrapper {
  margin-top: 24px !important;
  padding-top: 12px;
  align-items: start !important;
}

.scenario-entry-inline {
  padding-top: 6px !important;
}

.scenario-entry-inline .scenario-title {
  font-size: 14px !important;
  font-weight: 800 !important;
}

.scenario-entry-inline .scenario-desc {
  max-width: 620px !important;
  line-height: 1.35;
}
/* ===========================
   Profile page
   =========================== */
.profile-body {
  min-height: 100vh;
  background: #f3f7fb;
}

.profile-topbar {
  height: 66px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 28px;
  background: #ffffff;
  border-bottom: 1px solid #e2e8f0;
}

.profile-brand,
.profile-back-link {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: #0f172a;
  font-weight: 900;
  text-decoration: none;
}

.profile-back-link {
  min-height: 38px;
  padding: 0 14px;
  border-radius: 10px;
  background: #ecfeff;
  color: #115e59;
}

.profile-page {
  width: min(1120px, calc(100% - 36px));
  margin: 26px auto 56px;
}

.profile-hero,
.profile-card {
  border: 1px solid #dbe4ef;
  border-radius: 18px;
  background: #ffffff;
  box-shadow: 0 14px 30px rgba(15, 23, 42, 0.06);
}

.profile-hero {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 36px 20px 30px;
  background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
}

.profile-avatar {
  width: 86px;
  height: 86px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: linear-gradient(135deg, #0ea5e9 0%, #14b8a6 55%, #22c55e 100%);
  color: #ffffff;
  font-size: 34px;
  font-weight: 900;
  box-shadow: 0 16px 28px rgba(14, 165, 233, 0.25);
}

.profile-hero h1 {
  margin: 8px 0 0;
  color: #0f172a;
  font-size: 30px;
}

.profile-hero p,
.profile-muted {
  margin: 0;
  color: #64748b;
}

.profile-grid {
  display: grid;
  grid-template-columns: minmax(320px, 0.9fr) minmax(0, 1.3fr);
  gap: 18px;
  margin-top: 18px;
}

.profile-card {
  padding: 20px;
}

.profile-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 16px;
}

.profile-card-header h2 {
  margin: 0;
  color: #0f172a;
  font-size: 19px;
}

.profile-info-list,
.round-list,
.round-answers {
  display: grid;
  gap: 10px;
}

.profile-info-list div {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 12px;
  border-radius: 12px;
  background: #f8fafc;
  border: 1px solid #e2e8f0;
}

.profile-info-list span {
  color: #64748b;
  font-size: 13px;
}

.profile-info-list strong {
  color: #0f172a;
  text-align: right;
  word-break: break-word;
}

.profile-primary-btn,
.profile-secondary-btn {
  min-height: 38px;
  padding: 0 14px;
  border-radius: 10px;
  font-weight: 800;
  cursor: pointer;
}

.profile-primary-btn {
  border: none;
  background: linear-gradient(135deg, #0ea5e9 0%, #14b8a6 55%, #22c55e 100%);
  color: #ffffff;
}

.profile-secondary-btn {
  background: #f8fafc;
  color: #334155;
  border: 1px solid #cbd5e1;
}

.profile-password-form {
  display: grid;
  gap: 12px;
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid #e2e8f0;
}

.profile-password-form label {
  display: grid;
  gap: 6px;
  color: #475569;
  font-size: 13px;
  font-weight: 800;
}

.profile-password-form input {
  min-height: 42px;
  border: 1px solid #cbd5e1;
  border-radius: 11px;
  padding: 0 12px;
}

.profile-message {
  color: #b91c1c;
  font-weight: 700;
}

.profile-message.success {
  color: #15803d;
}

.round-list {
  max-height: 430px;
  overflow-y: auto;
}

.round-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 12px;
  width: 100%;
  padding: 14px;
  border: 1px solid #e2e8f0;
  border-radius: 14px;
  background: #f8fafc;
  text-align: left;
  cursor: pointer;
}

.round-item strong {
  display: block;
  color: #0f172a;
  margin-bottom: 4px;
}

.round-item span,
.round-item-meta span {
  color: #64748b;
  font-size: 12px;
}

.round-item-meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 8px;
}

.round-item-meta span {
  padding: 6px 8px;
  border-radius: 999px;
  background: #e0f2fe;
  color: #075985;
  font-weight: 800;
}

.profile-empty {
  padding: 22px;
  border-radius: 14px;
  background: #f8fafc;
  color: #64748b;
  text-align: center;
}

.round-detail {
  margin-top: 18px;
}

.round-analysis {
  margin-bottom: 16px;
  padding: 16px;
  border-radius: 14px;
  background: #eff6ff;
  border: 1px solid #dbeafe;
  color: #1e293b;
  line-height: 1.7;
}

.round-analysis h3 {
  margin: 0 0 8px;
  color: #1e3a8a;
}

.round-answer-card {
  padding: 16px;
  border: 1px solid #e2e8f0;
  border-radius: 14px;
  background: #ffffff;
}

.round-answer-header {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 10px;
}

.round-question,
.round-answer-block {
  white-space: pre-wrap;
  line-height: 1.65;
  color: #0f172a;
}

.round-answer-block {
  margin-top: 10px;
  padding: 12px;
  border-radius: 12px;
  background: #f8fafc;
}

.round-answer-block span {
  display: block;
  margin-bottom: 6px;
  color: #64748b;
  font-size: 12px;
  font-weight: 900;
  text-transform: uppercase;
}

.verdict-pill {
  padding: 6px 9px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 900;
  background: #e2e8f0;
  color: #334155;
}

.verdict-correct {
  background: #dcfce7;
  color: #166534;
}

.verdict-partial {
  background: #fef3c7;
  color: #92400e;
}

.verdict-wrong {
  background: #fee2e2;
  color: #991b1b;
}

@media (max-width: 860px) {
  .profile-grid,
  .round-item {
    grid-template-columns: 1fr;
  }

  .round-item-meta {
    justify-content: flex-start;
  }
}