/* ===== CSS 变量 ===== */
:root {
  --color-primary: #FF8C42;
  --color-primary-soft: #FFF3E8;
  --color-accent: #36CFA7;
  --color-accent-soft: #E4F8F2;
  --color-danger: #F25C5C;
  --color-danger-soft: #FDECEC;
  --color-warning: #FFD166;
  --color-warning-soft: #FFF8E1;

  --color-bg: #FAFAF8;
  --color-card: #FFFFFF;
  --color-border: #E8E4DF;
  --color-divider: #F0ECE8;

  --color-text: #2D3047;
  --color-text-sub: #6B7280;
  --color-text-mute: #9CA3AF;
  --color-text-disabled: #C2C8D0;

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;

  --shadow-card: 0 4px 15px rgba(255, 140, 66, 0.12);
  --shadow-fun: 0 6px 20px rgba(255, 140, 66, 0.18);

  --font-title: 'ZCOOL KuaiLe', 'PingFang SC', cursive;
  --font-body: 'Noto Sans SC', 'PingFang SC', sans-serif;
  --font-mono: 'JetBrains Mono', Menlo, Consolas, 'Courier New', monospace;

  --content-max-width: 900px;
}

/* ===== Reset ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 14px; scroll-behavior: smooth; }
body {
  background: linear-gradient(135deg, #E8E4DF 0%, #EAE8E4 50%, #E6E2DD 100%);
  color: var(--color-text);
  font-family: var(--font-body);
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  display: flex;
}

/* ===== 主内容区 ===== */
#main-area {
  margin-left: 0;
  flex: 1;
  min-height: 100vh;
  display: flex;
  justify-content: center;
}
#app {
  width: 100%;
  max-width: var(--content-max-width);
  min-height: 100vh;
  position: relative;
  background: var(--color-bg);
  box-shadow: 0 0 40px rgba(0,0,0,0.06);
}

button { font-family: inherit; cursor: pointer; border: none; outline: none; }
a { color: inherit; text-decoration: none; }

/* ===== 通用页面 ===== */
.page {
  min-height: 100vh;
  padding: 28px 32px 40px;
  background: linear-gradient(180deg, #FAFAF8 0%, #F5F0EB 100%);
  position: relative;
}
.page::before {
  content: '';
  position: absolute;
  right: -60px; top: 20px;
  width: 200px; height: 200px;
  border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%;
  background: rgba(255, 140, 66, 0.04);
  pointer-events: none;
}
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}
@keyframes slideUp {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}
@keyframes scaleIn {
  from { opacity: 0; transform: scale(0.95); }
  to { opacity: 1; transform: scale(1); }
}
.home-page { animation: fadeIn 0.3s ease; }
.category-page { animation: fadeIn 0.25s ease; }
.practice-page { animation: fadeIn 0.25s ease; }
.exam-list-page { animation: fadeIn 0.25s ease; }
.stats-page { animation: fadeIn 0.25s ease; }
.tags-page { animation: fadeIn 0.25s ease; }

/* ===== 页面头部 ===== */
.page-header {
  display: flex;
  align-items: center;
  gap: 14px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--color-divider);
  margin-bottom: 24px;
}
.page-header h2 {
  font-size: 22px;
  font-weight: 700;
}
.back-btn {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 6px 14px;
  background: var(--color-card);
  border-radius: 20px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  font-size: 13px;
  color: var(--color-text-sub);
  transition: background 0.15s, transform 0.15s;
  white-space: nowrap;
}
.back-btn:hover { background: #f0f0ee; transform: scale(1.05); }

/* ===== 首页 ===== */
.home-page .home-header {
  padding: 40px 32px 32px;
  background: linear-gradient(135deg, #E8702A 0%, #F0944A 40%, #F5B041 100%);
  border-radius: var(--radius-lg);
  color: #fff;
  box-shadow: 0 6px 20px rgba(232, 112, 42, 0.25);
  position: relative;
  overflow: hidden;
  margin-bottom: 8px;
}
.home-header::after {
  content: '';
  position: absolute;
  right: -30px; top: -30px;
  width: 120px; height: 120px;
  border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%;
  background: rgba(255,255,255,0.12);
  animation: heroFloat 6s ease-in-out infinite;
}
.home-header::before {
  content: '';
  position: absolute;
  right: 50px; bottom: -20px;
  width: 80px; height: 80px;
  border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%;
  background: rgba(255,209,102,0.3);
}
@keyframes heroFloat {
  0%, 100% { transform: translateY(0px) rotate(0deg); }
  50% { transform: translateY(-10px) rotate(2deg); }
}
.home-header-content {
  position: relative;
  z-index: 1;
}
.home-header h1 {
  font-size: 32px;
  font-weight: 700;
  font-family: var(--font-title);
  text-shadow: 1px 1px 0 rgba(0,0,0,0.1);
  position: relative;
  z-index: 1;
}
.home-header .subtitle {
  margin-top: 6px;
  font-size: 14px;
  opacity: 0.9;
  position: relative;
  z-index: 1;
}
/* 首页统计区（对齐小程序 hero-stats） */
.home-stats {
  margin-top: 24px;
  display: flex;
  gap: 12px;
}
.home-stat {
  flex: 1;
  background: rgba(255,255,255,0.16);
  border-radius: var(--radius-md);
  padding: 14px 0;
  text-align: center;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}
.home-stat-num {
  font-size: 28px;
  font-weight: 700;
  line-height: 1.2;
  text-shadow: 0 1px 4px rgba(0,0,0,0.12);
}
.home-stat-num.accent { color: #fff; }
.home-stat-unit {
  font-size: 14px;
  font-weight: 500;
  margin-left: 2px;
  opacity: 0.9;
}
.home-stat-label {
  margin-top: 4px;
  font-size: 12px;
  opacity: 0.9;
  text-shadow: 0 1px 2px rgba(0,0,0,0.1);
}
.home-stats-empty {
  margin-top: 20px;
  font-size: 13px;
  opacity: 0.8;
  padding: 10px 14px;
  background: rgba(255,255,255,0.14);
  border-radius: var(--radius-sm);
  display: inline-block;
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
}
/* 小程序推广 */
.home-mp-promo {
  margin: 20px 4px 0;
}
.mp-promo-card {
  display: flex;
  align-items: center;
  gap: 20px;
  background: linear-gradient(135deg, #fff 0%, var(--color-primary-soft) 100%);
  border-radius: var(--radius-lg);
  padding: 20px 24px;
  box-shadow: var(--shadow-card);
  border: 1px solid var(--color-border);
}
.mp-qrcode {
  width: 100px;
  height: 100px;
  border-radius: var(--radius-md);
  flex-shrink: 0;
  border: 2px solid #fff;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}
.mp-promo-info {
  flex: 1;
  min-width: 0;
}
.mp-promo-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 6px;
}
.mp-promo-desc {
  font-size: 13px;
  color: var(--color-text-sub);
  line-height: 1.5;
  margin-bottom: 10px;
}
.mp-promo-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.mp-tag {
  display: inline-block;
  font-size: 11px;
  padding: 3px 8px;
  border-radius: 20px;
  background: rgba(255, 140, 66, 0.1);
  color: var(--color-primary);
  font-weight: 500;
}
@media (max-width: 480px) {
  .mp-promo-card {
    flex-direction: column;
    text-align: center;
    padding: 20px 16px;
  }
  .mp-promo-tags {
    justify-content: center;
  }
}

/* section标题（对齐小程序） */
.home-section-title {
  margin: 24px 4px 16px;
  display: flex;
  align-items: baseline;
  gap: 10px;
}
.section-title-main {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-text);
}
.section-title-hint {
  font-size: 12px;
  color: var(--color-text-mute);
}
/* 分类卡片网格 */
.category-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
.category-card {
  position: relative;
  padding: 22px 20px 18px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  overflow: hidden;
}
.category-card:hover { transform: translateY(-4px); box-shadow: 0 10px 28px rgba(0,0,0,0.12); }
.category-card:active { transform: scale(0.97); }
.category-card .card-bar {
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 4px;
  background: var(--accent, #FF8C42);
  border-radius: 0 4px 4px 0;
}
.card-grade {
  font-size: 11px;
  color: var(--color-text-mute);
  letter-spacing: 1px;
}
.cat-icon { font-size: 28px; margin-top: 4px; margin-bottom: 6px; }
.cat-name {
  font-size: 22px;
  font-weight: 700;
  color: var(--accent, #FF8C42);
  font-family: var(--font-title);
  line-height: 1.2;
}
.cat-desc {
  margin-top: 4px;
  font-size: 12px;
  color: var(--color-text-sub);
}
.cat-stats {
  margin-top: 8px;
  font-size: 11px;
  color: var(--color-text-sub);
  line-height: 1.6;
}
.cat-tag {
  margin-top: 10px;
  display: inline-block;
  font-size: 11px;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--accent-soft, #FFF3E8);
  color: var(--accent, #FF8C42);
  font-weight: 600;
  font-family: var(--font-title);
}
.home-footer {
  margin-top: 28px;
  text-align: center;
  font-size: 12px;
  color: var(--color-text-mute);
}

/* ===== 分类详情页 ===== */
.section {
  margin-bottom: 28px;
  padding: 20px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: 0 2px 10px rgba(0,0,0,0.04);
}
.section h3 {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.badge {
  font-size: 11px;
  padding: 2px 8px;
  border-radius: 999px;
  background: var(--color-accent-soft);
  color: var(--color-accent);
  font-weight: 600;
}
.stats-bar {
  display: flex;
  gap: 16px;
  font-size: 13px;
  color: var(--color-text-sub);
  margin-bottom: 12px;
}
.wrong-hint {
  padding: 10px 14px;
  background: var(--color-danger-soft);
  border-radius: var(--radius-sm);
  font-size: 13px;
  color: var(--color-danger);
  margin-bottom: 12px;
}
.btn-group {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}
.tag-section {
  margin-top: 16px;
}
.tag-section h4 {
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 10px;
  color: var(--color-text-sub);
}
.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.tag-list .tag {
  font-size: 12px;
  padding: 4px 12px;
  border-radius: 999px;
  background: var(--color-accent-soft);
  color: var(--color-accent);
  cursor: pointer;
  transition: background 0.15s, color 0.15s, transform 0.1s;
}
.tag-list .tag:hover {
  background: var(--color-accent);
  color: #fff;
  transform: scale(1.05);
}
.exam-intro {
  margin-bottom: 14px;
}
.exam-intro p {
  font-size: 13px;
  color: var(--color-text-sub);
}
.exam-tip {
  font-size: 12px;
  color: var(--color-text-mute);
  margin-top: 4px;
  font-style: italic;
}

/* ===== 按钮 ===== */
.btn {
  height: 42px;
  line-height: 42px;
  text-align: center;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  padding: 0 20px;
  transition: transform 0.15s, opacity 0.15s, background 0.15s, box-shadow 0.15s;
}
.btn:hover { opacity: 0.92; }
.btn:active { transform: scale(0.97); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn.primary {
  background: var(--color-accent);
  color: #fff;
  box-shadow: 0 3px 9px rgba(54, 207, 167, 0.4);
}
.btn.primary:hover { box-shadow: 0 5px 15px rgba(54, 207, 167, 0.5); }
.btn.warning {
  background: var(--color-warning);
  color: #5D4E1A;
}
.btn.accent {
  background: linear-gradient(135deg, #E8702A, #F5B041);
  color: #fff;
  box-shadow: 0 3px 12px rgba(232, 112, 42, 0.35);
}
.btn.accent:hover { box-shadow: 0 6px 18px rgba(232, 112, 42, 0.45); }
.btn.outline {
  background: transparent;
  border: 1px solid var(--color-border);
  color: var(--color-text-sub);
}
.btn.outline:hover { border-color: var(--color-accent); color: var(--color-accent); }
.btn.danger-outline {
  background: transparent;
  border: 1px solid var(--color-danger);
  color: var(--color-danger);
}
.btn.danger-outline:hover { background: var(--color-danger-soft); }
.btn.big { height: 50px; line-height: 50px; font-size: 16px; padding: 0 30px; }
.btn-small {
  font-size: 12px;
  padding: 4px 10px;
  border-radius: 4px;
  background: #f3f4f6;
  color: var(--color-text-sub);
  transition: background 0.15s;
}
.btn-small:hover { background: #e5e7eb; }
.btn-small.danger { background: var(--color-danger-soft); color: var(--color-danger); }
.btn-small.danger:hover { background: var(--color-danger); color: #fff; }

/* ===== 练习页 ===== */
.question-card {
  background: var(--color-card);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  box-shadow: var(--shadow-card);
  margin-bottom: 18px;
}
.question-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 12px;
}
.q-id {
  font-size: 11px;
  padding: 2px 8px;
  border-radius: 999px;
  background: #f3f4f6;
  color: var(--color-text-mute);
  font-weight: 600;
  letter-spacing: 0.5px;
}
.q-tag {
  font-size: 10px;
  padding: 2px 8px;
  border-radius: 999px;
  background: var(--color-accent-soft);
  color: var(--color-accent);
  font-weight: 500;
}
.q-level {
  font-size: 10px;
  padding: 2px 8px;
  border-radius: 999px;
  background: #f3f4f6;
  color: var(--color-text-mute);
}
.q-wrong-badge {
  font-size: 10px;
  padding: 2px 8px;
  border-radius: 999px;
  background: var(--color-danger-soft);
  color: var(--color-danger);
  font-weight: 600;
}
.question-stem {
  font-size: 15px;
  color: var(--color-text);
  line-height: 1.8;
  word-break: break-word;
}
.question-stem p {
  margin-bottom: 8px;
  white-space: pre-wrap;
}
.question-stem pre.code-block {
  background: #1E293B;
  color: #E2E8F0;
  border-radius: 8px;
  padding: 14px 18px;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.6;
  white-space: pre;
  overflow-x: auto;
  margin: 10px 0;
  border: 1px solid #334155;
}
.question-image {
  margin-top: 10px;
}
.question-image img {
  max-width: 100%;
  border-radius: var(--radius-sm);
}

/* 题干多图：网格小卡片，避免单图占满整屏 */
.question-images {
  margin-top: 12px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 220px));
  gap: 10px;
  justify-content: start;
}
.question-images .question-image {
  margin-top: 0;
  width: 100%;
  height: 160px;
  object-fit: contain;
  border-radius: var(--radius-sm);
  cursor: zoom-in;
  transition: transform 0.15s ease;
  background: #fff;
  border: 1px solid var(--color-border);
  padding: 6px;
  box-sizing: border-box;
}
.question-images .question-image:hover {
  transform: scale(1.02);
}
@media (max-width: 600px) {
  .question-images {
    grid-template-columns: repeat(auto-fit, minmax(45%, 1fr));
  }
  .question-images .question-image {
    height: 140px;
  }
}

/* 选项内嵌图片 */
.option-image {
  display: inline-block;
  vertical-align: middle;
  max-width: 220px;
  max-height: 140px;
  margin-left: 6px;
  border-radius: 6px;
  cursor: zoom-in;
  background: #fff;
  border: 1px solid var(--color-border);
}
.option-image:hover {
  border-color: var(--color-accent);
}

/* 图片放大预览遮罩 */
.img-preview-mask {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.85);
  z-index: 9999;
  justify-content: center;
  align-items: center;
  cursor: zoom-out;
  padding: 24px;
}
.img-preview-mask.show {
  display: flex;
}
.img-preview-content {
  max-width: 96vw;
  max-height: 92vh;
  border-radius: 8px;
  box-shadow: 0 12px 36px rgba(0, 0, 0, 0.5);
  background: #fff;
}
.img-preview-close {
  position: absolute;
  top: 16px;
  right: 24px;
  font-size: 36px;
  color: #fff;
  line-height: 1;
  cursor: pointer;
  user-select: none;
}

/* 选项 */
.options-area {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 18px;
}
.option {
  display: flex;
  align-items: center;
  padding: 14px 16px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  border: 2px solid var(--color-border);
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s, transform 0.15s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.15s;
  animation: scaleIn 0.2s ease both;
}
.option:nth-child(1) { animation-delay: 0.02s; }
.option:nth-child(2) { animation-delay: 0.06s; }
.option:nth-child(3) { animation-delay: 0.10s; }
.option:nth-child(4) { animation-delay: 0.14s; }
.option:hover { border-color: #c0bdb8; transform: scale(1.005); box-shadow: 0 2px 8px rgba(0,0,0,0.05); }
.option.selected { border-color: var(--color-accent); background: var(--color-accent-soft); box-shadow: 0 0 0 1px var(--color-accent); transform: scale(1.01); }
.option.correct { border-color: var(--color-accent); background: var(--color-accent-soft); box-shadow: 0 0 0 1px var(--color-accent); }
.option.correct .option-key { background: var(--color-accent); color: #fff; }
.option.incorrect { border-color: var(--color-danger); background: var(--color-danger-soft); box-shadow: 0 0 0 1px var(--color-danger); }
.option.incorrect .option-key { background: var(--color-danger); color: #fff; }
.option-key {
  width: 32px; height: 32px;
  border-radius: 50%;
  background: var(--color-accent-soft);
  color: var(--color-accent);
  font-size: 14px;
  font-weight: 700;
  line-height: 32px;
  text-align: center;
  flex-shrink: 0;
}
.option-text {
  flex: 1;
  margin-left: 12px;
  font-size: 14px;
  color: var(--color-text);
  line-height: 1.7;
  word-break: break-word;
  white-space: pre-wrap;
}

/* 编程题提示与代码区 */
.coding-area {
  margin-bottom: 18px;
}
.coding-hint {
  padding: 14px 18px;
  background: var(--color-warning-soft);
  border-radius: var(--radius-sm);
  font-size: 13px;
  color: #8C6D16;
}
.coding-code {
  margin-top: 14px;
  background: #1E293B;
  color: #E2E8F0;
  border-radius: 8px;
  padding: 16px 20px;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.6;
  white-space: pre;
  overflow-x: auto;
  border: 1px solid #334155;
}

/* 答案区 */
.answer-area {
  margin-bottom: 18px;
}
.answer-reveal {
  padding: 16px 20px;
  background: var(--color-accent-soft);
  border-radius: var(--radius-md);
  border-left: 4px solid var(--color-accent);
}
.answer-reveal h4 {
  font-size: 15px;
  color: var(--color-accent);
  margin-bottom: 8px;
}
.explanation {
  margin-top: 12px;
  padding: 12px 14px 12px 16px;
  font-size: 13px;
  color: var(--color-text-sub);
  line-height: 1.8;
  word-break: break-word;
  background: #F8F7F4;
  border-radius: var(--radius-sm);
  position: relative;
  border-left: 3px solid var(--color-accent);
}
.explanation code {
  background: #f0f0f0;
  padding: 1px 4px;
  border-radius: 3px;
  font-family: var(--font-mono);
  font-size: 12px;
}
.explanation pre {
  background: #1E293B;
  color: #E2E8F0;
  padding: 10px 14px;
  border-radius: 6px;
  margin: 8px 0;
  font-family: var(--font-mono);
  font-size: 12px;
  overflow-x: auto;
}
.source {
  margin-top: 10px;
  font-size: 11px;
  color: var(--color-text-mute);
}

/* 反馈 */
.feedback-area {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--color-divider);
  display: flex;
  align-items: center;
  gap: 8px;
}
.feedback-label { font-size: 12px; color: var(--color-text-mute); }
.feedback-btn {
  font-size: 12px;
  padding: 4px 12px;
  border-radius: 4px;
  background: #f3f4f6;
  color: var(--color-text-sub);
  transition: background 0.15s, color 0.15s;
}
.feedback-btn:hover { background: #e5e7eb; }
.feedback-btn.active { background: var(--color-accent); color: #fff; }

/* 操作栏 */
.action-bar {
  display: flex;
  gap: 10px;
  margin-top: 12px;
  padding-bottom: 20px;
}

/* 空状态 */
.empty-state {
  text-align: center;
  padding: 80px 20px;
}
.empty-state p {
  font-size: 17px;
  color: var(--color-text-sub);
  margin-bottom: 8px;
}
.empty-state .btn { margin-top: 20px; }

/* ===== 错题本 ===== */
.wrong-item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 16px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  margin-bottom: 8px;
  transition: transform 0.15s, box-shadow 0.15s;
}
.wrong-item:hover { transform: translateY(-1px); box-shadow: 0 4px 12px rgba(0,0,0,0.08); }
.wrong-idx {
  width: 30px; height: 30px;
  border-radius: 50%;
  background: var(--color-danger-soft);
  color: var(--color-danger);
  font-size: 13px;
  font-weight: 700;
  line-height: 30px;
  text-align: center;
  flex-shrink: 0;
}
.wrong-stem {
  flex: 1;
  font-size: 13px;
  color: var(--color-text);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.wrong-answer {
  font-size: 12px;
  color: var(--color-accent);
  font-weight: 600;
  flex-shrink: 0;
}
.wrong-actions { flex-shrink: 0; }

/* ===== 模拟考 ===== */
.exam-hero {
  text-align: center;
  padding: 28px 24px;
  background: var(--color-card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  margin-bottom: 24px;
}
.exam-hero h3 {
  font-size: 22px;
  font-weight: 700;
  font-family: var(--font-title);
  margin-bottom: 18px;
}
.exam-rules {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin-bottom: 18px;
}
.rule-item {
  font-size: 14px;
  color: var(--color-text-sub);
}
.exam-goal {
  text-align: left;
  padding: 16px 18px;
  background: var(--color-accent-soft);
  border-radius: var(--radius-md);
}
.exam-goal h4 {
  font-size: 14px;
  color: var(--color-accent);
  margin-bottom: 6px;
}
.exam-goal p {
  font-size: 13px;
  color: var(--color-text);
  margin-bottom: 10px;
}
.exam-goal ul {
  list-style: disc;
  padding-left: 18px;
  font-size: 12px;
  color: var(--color-text-sub);
  line-height: 1.9;
}

/* 考试进行中 */
.exam-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--color-card);
  border-radius: var(--radius-md);
  padding: 12px 18px;
  box-shadow: var(--shadow-card);
  margin-bottom: 14px;
}
.exam-timer {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-accent);
  font-family: var(--font-mono);
}
.exam-timer.timer-warning { color: var(--color-danger); animation: blink 1s infinite; }
@keyframes blink { 50% { opacity: 0.5; } }
.exam-progress { font-size: 14px; font-weight: 600; }

/* 题目导航 */
.exam-question-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 14px;
  padding: 12px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
}
.q-dot {
  width: 34px; height: 34px;
  border-radius: 10px;
  background: var(--color-bg);
  color: var(--color-text-sub);
  font-size: 12px;
  font-weight: 600;
  line-height: 34px;
  text-align: center;
  cursor: pointer;
  transition: background 0.15s, color 0.15s, transform 0.15s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.15s;
}
.q-dot:hover { background: #e5e7eb; transform: scale(1.1); }
.q-dot.current { background: var(--color-accent); color: #fff; box-shadow: 0 2px 8px rgba(54,207,167,0.45); transform: scale(1.08); }
.q-dot.answered { background: var(--color-accent-soft); color: var(--color-accent); }
.q-dot.answered.current { background: var(--color-accent); color: #fff; }

.exam-nav-bar {
  display: flex;
  gap: 10px;
  margin-top: 14px;
}

/* 考试结果 */
.result-hero {
  text-align: center;
  padding: 36px 24px;
  background: linear-gradient(180deg, var(--color-card) 0%, #FAFAF8 100%);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  margin-bottom: 24px;
  position: relative;
  overflow: hidden;
}
.result-hero::before {
  content: '';
  position: absolute;
  right: -30px; top: -20px;
  width: 100px; height: 100px;
  border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%;
  background: rgba(54, 207, 167, 0.06);
  pointer-events: none;
}
.score-circle {
  width: 130px; height: 130px;
  border-radius: 50%;
  margin: 0 auto 18px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  border: 5px solid;
  position: relative;
  z-index: 1;
  animation: scaleIn 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}
.score-circle.pass {
  border-color: var(--color-accent);
  box-shadow: 0 0 24px rgba(54, 207, 167, 0.2);
}
.score-circle.fail {
  border-color: var(--color-danger);
  box-shadow: 0 0 24px rgba(242, 92, 92, 0.2);
}
.score-num {
  font-size: 40px;
  font-weight: 900;
  font-family: var(--font-title);
  line-height: 1;
}
.score-circle.pass .score-num { color: var(--color-accent); }
.score-circle.fail .score-num { color: var(--color-danger); }
.score-total { font-size: 14px; color: var(--color-text-mute); }
.result-summary {
  display: flex;
  justify-content: center;
  gap: 24px;
  font-size: 14px;
  color: var(--color-text-sub);
}

/* 诊断表 */
.diag-section {
  margin-bottom: 24px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  padding: 20px;
  box-shadow: 0 2px 10px rgba(0,0,0,0.04);
}
.diag-section h3 { font-size: 17px; font-weight: 700; margin-bottom: 14px; }
.diag-table {
  border-radius: var(--radius-md);
  overflow: hidden;
}
.diag-header {
  display: grid;
  grid-template-columns: 2fr 1.5fr 1fr;
  padding: 10px 16px;
  background: var(--color-bg);
  font-size: 12px;
  font-weight: 600;
  color: var(--color-text-mute);
}
.diag-row {
  display: grid;
  grid-template-columns: 2fr 1.5fr 1fr;
  padding: 10px 16px;
  font-size: 13px;
  border-top: 1px solid var(--color-divider);
}
.diag-row.weak { background: var(--color-danger-soft); }
.level-badge {
  font-size: 11px;
  padding: 2px 8px;
  border-radius: 999px;
  font-weight: 600;
  text-align: center;
}
.level-badge.weak { background: var(--color-danger-soft); color: var(--color-danger); }
.level-badge.mid { background: var(--color-warning-soft); color: #8C6D16; }
.level-badge.good { background: var(--color-accent-soft); color: var(--color-accent); }

/* 错题回顾（折叠展开） */
.wrong-review-section {
  margin-bottom: 24px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  box-shadow: 0 2px 10px rgba(0,0,0,0.04);
}
.wrong-review-section > .wrong-review-summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 17px;
  font-weight: 700;
  user-select: none;
}
.wrong-review-section > .wrong-review-summary::-webkit-details-marker { display: none; }
.wrong-review-section > .wrong-review-summary::before {
  content: '▶';
  display: inline-block;
  margin-right: 8px;
  font-size: 12px;
  color: var(--color-text-mute);
  transition: transform 0.15s ease;
}
.wrong-review-section[open] > .wrong-review-summary::before {
  transform: rotate(90deg);
}
.wrong-review-toggle {
  font-size: 12px;
  font-weight: 400;
  color: var(--color-text-sub);
}
.wrong-review-body {
  margin-top: 14px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

/* 单条错题卡（每题独立折叠） */
.wrong-card {
  background: var(--color-bg);
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
  overflow: hidden;
}
.wrong-card > .wrong-card-head {
  list-style: none;
  cursor: pointer;
  padding: 12px 14px;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px 12px;
  font-size: 13px;
  user-select: none;
}
.wrong-card > .wrong-card-head::-webkit-details-marker { display: none; }
.wrong-card > .wrong-card-head::before {
  content: '▶';
  font-size: 10px;
  color: var(--color-text-mute);
  transition: transform 0.15s ease;
}
.wrong-card[open] > .wrong-card-head::before {
  transform: rotate(90deg);
}
.wrong-card[open] > .wrong-card-head .wrong-card-toggle {
  display: none;
}
.wrong-idx {
  font-weight: 700;
  color: var(--color-accent);
}
.wrong-kp {
  font-size: 12px;
  color: var(--color-text-sub);
  background: var(--color-accent-soft);
  padding: 2px 8px;
  border-radius: 10px;
}
.wrong-card-summary {
  flex: 1;
  font-size: 12px;
  color: var(--color-text-sub);
}
.wrong-card-summary b { color: var(--color-text); }
.wrong-card-summary b.correct-answer { color: var(--color-accent); }
.wrong-card-toggle {
  font-size: 12px;
  color: var(--color-text-mute);
}
.wrong-card-body {
  padding: 4px 14px 14px 28px;
  border-top: 1px dashed var(--color-border);
}
.wrong-card-body .wrong-stem p {
  margin: 6px 0;
  line-height: 1.65;
  font-size: 14px;
}
.wrong-card-body .wrong-stem .code-block {
  margin: 8px 0;
}
.wrong-card-body .question-images {
  margin-top: 8px;
}

/* 选项答题对照 */
.wrong-options {
  margin-top: 10px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.wrong-opt {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 12px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: #fff;
  font-size: 13px;
}
.wrong-opt .opt-key {
  width: 24px; height: 24px;
  border-radius: 50%;
  background: var(--color-bg);
  color: var(--color-text-sub);
  font-weight: 700;
  font-size: 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.wrong-opt .opt-body {
  flex: 1;
  line-height: 1.5;
  word-break: break-word;
}
.wrong-opt .opt-mark {
  font-size: 12px;
  font-weight: 600;
  flex-shrink: 0;
}
.wrong-opt.opt-right {
  background: var(--color-accent-soft);
  border-color: var(--color-accent);
}
.wrong-opt.opt-right .opt-key {
  background: var(--color-accent);
  color: #fff;
}
.wrong-opt.opt-right .opt-mark { color: var(--color-accent); }
.wrong-opt.opt-wrong {
  background: var(--color-danger-soft);
  border-color: var(--color-danger);
}
.wrong-opt.opt-wrong .opt-key {
  background: var(--color-danger);
  color: #fff;
}
.wrong-opt.opt-wrong .opt-mark { color: var(--color-danger); }
.wrong-unanswered {
  margin-top: 8px;
  font-size: 12px;
  color: var(--color-danger);
  font-weight: 600;
}
.wrong-explanation {
  margin-top: 12px;
  padding: 10px 12px;
  background: var(--color-warning-soft, #FFF8E6);
  border-left: 3px solid var(--color-warning, #E0A92C);
  border-radius: 4px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--color-text);
}
.wrong-exp-label {
  font-weight: 700;
  color: #8C6D16;
  margin-right: 4px;
}
.correct-answer { color: var(--color-accent) !important; }

/* 考试历史 */
.history-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.history-item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 16px 18px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  transition: transform 0.15s;
}
.history-item:hover { transform: translateY(-1px); }
.history-idx {
  width: 34px; height: 34px;
  border-radius: 50%;
  background: var(--color-accent-soft);
  color: var(--color-accent);
  font-size: 13px;
  font-weight: 700;
  line-line: 34px;
  text-align: center;
  flex-shrink: 0;
}
.history-info { flex: 1; }
.history-score { font-size: 17px; font-weight: 700; }
.history-date { font-size: 12px; color: var(--color-text-sub); margin-top: 2px; }
.history-detail { font-size: 12px; color: var(--color-text-mute); margin-top: 2px; }

/* ===== 编程题专用样式 ===== */
.coding-question-view {
  margin-top: 10px;
}
.coding-question-view .coding-section {
  margin-bottom: 16px;
}
.coding-section-label {
  font-size: 12px;
  font-weight: 600;
  color: var(--color-text-mute);
  margin-bottom: 6px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* ===== 加载动画 ===== */
.loading-state {
  text-align: center;
  padding: 60px 20px;
}
.loading-spinner {
  width: 36px; height: 36px;
  border: 3px solid var(--color-border);
  border-top-color: var(--color-accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  margin: 0 auto 16px;
}
@keyframes spin {
  to { transform: rotate(360deg); }
}
.loading-text {
  font-size: 14px;
  color: var(--color-text-mute);
}

/* ============================== */
/* ===== 新分类页（小程序对齐）===== */
/* ============================== */
.category-page .cat-head {
  padding: 4px 4px 18px;
  border-bottom: 1px solid var(--color-divider);
  position: relative;
}
.back-btn-inline {
  display: inline-block;
  padding: 4px 12px;
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  font-size: 12px;
  color: var(--color-text-sub);
  margin-bottom: 12px;
  cursor: pointer;
  transition: all 0.15s;
}
.back-btn-inline:hover { border-color: var(--accent); color: var(--accent); }
.cat-head .head-kicker {
  font-size: 12px;
  color: var(--color-text-mute);
  letter-spacing: 1px;
}
.cat-head .head-title {
  margin-top: 4px;
  font-size: 30px;
  font-weight: 700;
  color: var(--accent);
  letter-spacing: 0.5px;
  font-family: var(--font-title);
}
.cat-head .head-sub {
  margin-top: 6px;
  font-size: 13px;
  color: var(--color-text-sub);
}
.cat-head .head-sub .dot {
  margin: 0 8px;
  color: var(--color-text-mute);
}

/* 通用卡片（小程序版） */
.cat-card {
  margin-top: 18px;
  padding: 18px 18px 16px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
  position: relative;
  overflow: hidden;
  animation: slideUp 0.3s ease both;
}
.cat-card:nth-child(2) { animation-delay: 0.05s; }
.cat-card:nth-child(3) { animation-delay: 0.1s; }
.cat-card:nth-child(4) { animation-delay: 0.15s; }
.cat-card::before {
  content: '';
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 4px;
  background: var(--accent);
  border-radius: 0 4px 4px 0;
}
.cat-card.exam-card {
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.15s;
}
.cat-card.exam-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(0,0,0,0.1);
}
.cat-card .card-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
}
.cat-card .card-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-text);
}
.cat-card .card-count {
  font-size: 12px;
  color: var(--accent);
  background: var(--color-bg);
  padding: 3px 10px;
  border-radius: 999px;
  font-weight: 600;
}
.exam-card .card-count.exam-badge {
  background: linear-gradient(135deg, var(--color-danger), var(--color-warning));
  color: #fff;
  font-family: var(--font-title);
}
.cat-card .card-desc {
  margin-top: 8px;
  font-size: 13px;
  color: var(--color-text-sub);
  line-height: 1.6;
}
.cat-card .card-progress {
  margin-top: 14px;
  display: flex;
  gap: 10px;
}
.cat-card .progress-item {
  flex: 1;
  background: var(--color-bg);
  border-radius: var(--radius-sm);
  padding: 10px 0;
  text-align: center;
  display: flex;
  flex-direction: column;
}
.cat-card .progress-item .num {
  display: block;
  font-size: 20px;
  font-weight: 700;
  color: var(--color-text);
  line-height: 1.2;
}
.cat-card .progress-item .num.accent { color: var(--accent); }
.cat-card .progress-item .num.danger { color: var(--color-danger); }
.cat-card .progress-item .label {
  display: block;
  margin-top: 2px;
  font-size: 11px;
  color: var(--color-text-mute);
}
.cat-card .card-actions {
  margin-top: 16px;
  display: flex;
  gap: 10px;
}
.cat-btn {
  flex: 1;
  height: 40px;
  line-height: 40px;
  text-align: center;
  border-radius: 10px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: opacity 0.15s, transform 0.15s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.15s;
}
.cat-btn:hover { opacity: 0.9; transform: translateY(-1px); }
.cat-btn:active { transform: scale(0.97); }
.cat-btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 4px 12px var(--accent-shadow, rgba(54, 207, 167, 0.3));
  font-family: var(--font-title);
}
.cat-btn-outline {
  background: transparent;
  border: 2px solid var(--accent);
  color: var(--accent);
}
.cat-btn-outline:hover { background: var(--accent); color: #fff; }
.btn-sm { height: 34px; line-height: 30px; font-size: 13px; }
.cat-card .card-sub {
  margin-top: 12px;
  padding-top: 10px;
  border-top: 1px solid var(--color-divider);
  font-size: 13px;
  color: var(--color-text-sub);
  cursor: pointer;
  transition: color 0.15s;
}
.cat-card .card-sub:hover { color: var(--accent); }

.link-row {
  margin-top: 22px;
  padding: 14px 18px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 14px;
  color: var(--color-text);
  cursor: pointer;
  transition: opacity 0.15s;
}
.link-row:hover { opacity: 0.85; }
.link-arrow {
  color: var(--color-text-mute);
  font-size: 22px;
  line-height: 1;
}
.clear-btn {
  margin-top: 22px;
  padding: 14px 0;
  text-align: center;
  font-size: 13px;
  color: var(--color-danger);
  border-top: 1px solid var(--color-divider);
  cursor: pointer;
  transition: opacity 0.15s;
}
.clear-btn:hover { opacity: 0.7; }

/* ============================== */
/* ===== 模拟考列表页 ===== */
/* ============================== */
.exam-list-page .exam-hero {
  margin-top: 8px;
  padding: 28px 24px;
  background: linear-gradient(135deg, #E8702A, #F0944A 50%, #F5B041);
  border-radius: var(--radius-lg);
  color: #fff;
  text-align: center;
  box-shadow: 0 8px 24px rgba(232,112,42,0.25);
  position: relative;
  overflow: hidden;
}
.exam-list-page .exam-hero::before {
  content: '';
  position: absolute;
  left: -20px; bottom: -20px;
  width: 80px; height: 80px;
  border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%;
  background: rgba(255,209,102,0.3);
}
.exam-list-page .exam-hero::after {
  content: '';
  position: absolute;
  right: -40px; top: -40px;
  width: 130px; height: 130px;
  background: rgba(255,255,255,0.12);
  border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%;
  animation: heroFloat 6s ease-in-out infinite;
}
.exam-list-page .exam-hero .hero-title {
  font-size: 24px;
  font-weight: 700;
  font-family: var(--font-title);
  position: relative;
  z-index: 1;
}
.exam-list-page .fact-strip {
  margin-top: 16px;
  display: flex;
  background: var(--color-card);
  border-radius: var(--radius-md);
  padding: 16px 0;
  box-shadow: var(--shadow-card);
}
.exam-list-page .fact-item {
  flex: 1;
  text-align: center;
  border-right: 1px solid var(--color-divider);
}
.exam-list-page .fact-item:last-child { border-right: none; }
.exam-list-page .fact-value {
  display: flex;
  justify-content: center;
  align-items: baseline;
  gap: 4px;
}
.exam-list-page .fact-num {
  font-size: 26px;
  font-weight: 700;
  color: var(--accent);
  font-family: var(--font-title);
}
.exam-list-page .fact-unit {
  font-size: 12px;
  color: var(--color-text-sub);
}
.exam-list-page .fact-label {
  margin-top: 4px;
  font-size: 12px;
  color: var(--color-text-mute);
}
.exam-list-page .start-section {
  margin-top: 18px;
}
.exam-list-page .start-btn {
  display: block;
  width: 100%;
  height: 52px;
  background: var(--accent);
  color: #fff;
  font-size: 17px;
  font-weight: 700;
  font-family: var(--font-title);
  border: none;
  border-radius: 12px;
  cursor: pointer;
  box-shadow: 0 6px 18px rgba(0,0,0,0.12);
  transition: transform 0.1s, opacity 0.15s;
}
.exam-list-page .start-btn:hover { opacity: 0.93; }
.exam-list-page .start-btn:active { transform: scale(0.99); }
.exam-list-page .start-btn.disabled {
  opacity: 0.5; cursor: not-allowed;
}
.exam-list-page .resume-btn {
  display: block;
  width: 100%;
  margin-top: 10px;
  height: 42px;
  background: transparent;
  color: var(--accent);
  border: 2px solid var(--accent);
  border-radius: 8px;
  font-size: 13px;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
}
.exam-list-page .resume-btn:hover { background: var(--accent); color: #fff; }
.exam-list-page .history-section { margin-top: 22px; }
.exam-list-page .history-head { margin-bottom: 10px; }
.exam-list-page .section-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-text-sub);
}
.exam-list-page .history-card {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 16px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  margin-bottom: 8px;
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.15s;
  position: relative;
}
.exam-list-page .history-card:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}
.exam-list-page .history-score {
  display: flex;
  align-items: baseline;
  flex-shrink: 0;
}
.exam-list-page .history-score-num {
  font-size: 24px;
  font-weight: 700;
  color: var(--accent);
  font-family: var(--font-title);
}
.exam-list-page .history-score-unit {
  font-size: 12px;
  color: var(--color-text-mute);
}
.exam-list-page .history-detail { flex: 1; }
.exam-list-page .history-row {
  display: flex;
  gap: 12px;
  font-size: 13px;
  font-weight: 600;
}
.exam-list-page .history-correct { color: var(--color-accent); }
.exam-list-page .history-wrong { color: var(--color-danger); }
.exam-list-page .history-time {
  font-size: 11px;
  color: var(--color-text-mute);
  margin-top: 2px;
}
.exam-list-page .history-arrow {
  color: var(--color-text-mute);
  font-size: 22px;
}
.exam-list-page .history-del {
  position: absolute;
  right: 36px;
  top: 8px;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: transparent;
  color: var(--color-text-mute);
  font-size: 16px;
  line-height: 18px;
  cursor: pointer;
  border: none;
  transition: background 0.15s, color 0.15s;
}
.exam-list-page .history-del:hover {
  background: var(--color-danger-soft);
  color: var(--color-danger);
}
.exam-list-page .empty-history {
  margin-top: 22px;
  padding: 36px 24px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  text-align: center;
  font-size: 13px;
  color: var(--color-text-mute);
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
}
.exam-list-page .answer-card {
  margin-top: 20px;
  padding: 18px 20px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
}
.exam-list-page .answer-item { margin-bottom: 14px; }
.exam-list-page .answer-item:last-child { margin-bottom: 0; }
.exam-list-page .answer-title {
  font-size: 14px;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 4px;
}
.exam-list-page .answer-text {
  font-size: 13px;
  color: var(--color-text-sub);
  line-height: 1.7;
}
.exam-list-page .scope-card {
  margin-top: 18px;
  padding: 18px 20px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
}
.exam-list-page .scope-header { margin-bottom: 12px; }
.exam-list-page .scope-title {
  font-size: 14px;
  font-weight: 700;
  color: var(--color-text);
}
.exam-list-page .tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.exam-list-page .kp-tag {
  display: inline-block;
  padding: 4px 12px;
  font-size: 12px;
  background: var(--color-accent-soft);
  color: var(--color-accent);
  border-radius: 999px;
  font-weight: 500;
}

/* ============================== */
/* ===== 按标签练习页 ===== */
/* ============================== */
.tags-page .tags-hint {
  margin-top: 8px;
  padding: 14px 18px;
  background: var(--color-warning-soft);
  border-radius: var(--radius-sm);
  font-size: 13px;
  color: #8C6D16;
  line-height: 1.6;
}
.tags-page .tags-toolbar {
  margin-top: 16px;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
}
.toolbar-btn {
  padding: 6px 14px;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  font-size: 12px;
  color: var(--color-text-sub);
  cursor: pointer;
  transition: all 0.15s;
}
.toolbar-btn:hover { border-color: var(--accent); color: var(--accent); }
.toolbar-info {
  margin-left: auto;
  font-size: 12px;
  color: var(--color-text-mute);
}
.toolbar-info .toolbar-match {
  color: var(--accent);
  font-weight: 600;
}
.tags-page .tag-grid {
  margin-top: 14px;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 10px;
}
.tag-chip {
  padding: 12px 14px;
  background: var(--color-card);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s, transform 0.15s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.15s;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.tag-chip:hover { border-color: var(--accent); transform: translateY(-1px); }
.tag-chip.tag-chip-active {
  border-color: var(--accent);
  background: var(--color-accent-soft);
}
.tag-chip .chip-name {
  font-size: 13px;
  color: var(--color-text);
  font-weight: 500;
}
.tag-chip.tag-chip-active .chip-name { color: var(--accent); font-weight: 600; }
.tag-chip .chip-count {
  font-size: 11px;
  color: var(--color-text-mute);
  background: var(--color-bg);
  padding: 2px 8px;
  border-radius: 999px;
}
.tag-chip.tag-chip-active .chip-count {
  background: var(--accent);
  color: #fff;
}
.tags-bottom-bar {
  margin-top: 24px;
  padding: 16px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: 0 -2px 12px rgba(0,0,0,0.04);
  position: sticky;
  bottom: 0;
}
.tags-bottom-bar .start-btn {
  display: block;
  width: 100%;
  height: 48px;
  background: var(--accent);
  color: #fff;
  font-size: 16px;
  font-weight: 700;
  font-family: var(--font-title);
  border: none;
  border-radius: 10px;
  cursor: pointer;
  transition: opacity 0.15s, transform 0.1s;
}
.tags-bottom-bar .start-btn:hover { opacity: 0.93; }
.tags-bottom-bar .start-btn.disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ============================== */
/* ===== 学习记录（错题本）页 ===== */
/* ============================== */
.stats-page .stats-summary {
  margin-top: 8px;
  padding: 20px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
}
.stats-page .summary-title {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 14px;
}
.stats-page .summary-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}
.stats-page .grid-item {
  background: var(--color-bg);
  border-radius: var(--radius-sm);
  padding: 14px 0;
  text-align: center;
}
.stats-page .grid-num {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-text);
  font-family: var(--font-title);
}
.stats-page .grid-num.accent { color: var(--accent); }
.stats-page .grid-num .unit {
  font-size: 14px;
  color: var(--color-text-mute);
  margin-left: 2px;
}
.stats-page .grid-label {
  margin-top: 4px;
  font-size: 11px;
  color: var(--color-text-mute);
}
.stats-page .sub-stats {
  margin-top: 14px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}
.stats-page .sub-card {
  padding: 12px 14px;
  background: var(--color-bg);
  border-radius: var(--radius-sm);
}
.stats-page .sub-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
}
.stats-page .sub-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--color-text);
}
.stats-page .sub-count {
  font-size: 12px;
  color: var(--accent);
}
.stats-page .sub-body {
  margin-top: 4px;
  font-size: 12px;
  color: var(--color-text-sub);
}
.stats-page .wrong-section {
  margin-top: 18px;
  padding: 18px 20px;
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: 0 2px 10px rgba(0,0,0,0.04);
}
.stats-page .wrong-section-title {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 14px;
}
.stats-page .tag-stats { margin-bottom: 14px; }
.stats-page .tag-stats-title {
  font-size: 12px;
  color: var(--color-text-mute);
  margin-bottom: 8px;
}
.stats-page .tag-stats-list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.tag-stat-item {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 4px 10px;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  font-size: 12px;
  cursor: pointer;
  transition: all 0.15s;
}
.tag-stat-item:hover { border-color: var(--accent); color: var(--accent); }
.tag-stat-item.tag-stat-item-active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}
.tag-stat-item .tag-stat-count {
  font-size: 10px;
  opacity: 0.85;
}
.stats-page .action-row {
  display: flex;
  gap: 10px;
  margin-bottom: 14px;
}
.stats-page .wrong-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.stats-page .empty {
  padding: 30px 20px;
  text-align: center;
  font-size: 13px;
  color: var(--color-text-mute);
  background: var(--color-bg);
  border-radius: var(--radius-sm);
}
.stats-page .wrong-item {
  padding: 12px 14px;
  background: var(--color-bg);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background 0.15s;
}
.stats-page .wrong-item:hover { background: var(--color-accent-soft); }
.stats-page .wrong-head {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 11px;
  color: var(--color-text-mute);
  margin-bottom: 4px;
}
.stats-page .wrong-id {
  font-weight: 600;
  color: var(--color-text-sub);
}
.stats-page .wrong-summary {
  font-size: 13px;
  color: var(--color-text);
  line-height: 1.5;
  word-break: break-word;
}
.stats-page .wrong-tags {
  margin-top: 6px;
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
}
.wrong-tag {
  font-size: 10px;
  padding: 2px 8px;
  border-radius: 999px;
  background: var(--color-accent-soft);
  color: var(--color-accent);
}
.wrong-tag.wrong-tag-coding {
  background: var(--color-warning-soft);
  color: #8C6D16;
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
  :root { --content-max-width: 100%; }
  #main-area { margin-left: 0; }
  .category-grid { grid-template-columns: 1fr; }
  .page { padding: 16px 16px 24px; }
  .question-card { padding: 14px 16px; }
  .exam-rules { flex-direction: column; gap: 8px; }
  .home-stats { flex-direction: column; gap: 8px; }
  .home-stat { display: flex; align-items: center; gap: 10px; padding: 10px 14px; text-align: left; }
  .home-stat-num { font-size: 22px; }
  .home-stat-label { margin-top: 0; }
  .home-header { padding: 28px 20px 24px; }
  .home-header h1 { font-size: 26px; }
}
@media (min-width: 769px) and (max-width: 1200px) {
  :root { --content-max-width: 800px; }
}
@media (min-width: 1200px) {
  :root { --content-max-width: 960px; }
}