/* ============================================
   小学识字网站 - 儿童友好样式
   主色调：暖黄 + 天蓝 + 草绿
   ============================================ */

:root {
  /* 色彩系统 */
  --color-primary: #FFB347;      /* 暖橙黄 - 主色调 */
  --color-secondary: #87CEEB;   /* 天蓝色 */
  --color-success: #90EE90;      /* 浅草绿 */
  --color-danger: #FFB6C1;       /* 浅粉红 */
  --color-purple: #DDA0DD;       /* 淡紫色 */
  --color-bg: #FFF9E6;           /* 米黄背景 */
  --color-card: #FFFFFF;
  --color-text: #333333;
  --color-text-light: #666666;
  --color-border: #FFD700;

  /* 阴影 */
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.1);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.12);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.15);

  /* 圆角 */
  --radius-sm: 12px;
  --radius-md: 20px;
  --radius-lg: 32px;
  --radius-full: 50px;

  /* 字体 */
  --font-main: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-char: "KaiTi", "STKaiti", "楷体", serif;  /* 楷体用于显示汉字 */
}

/* 重置 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: var(--font-main);
  background: var(--color-bg);
  color: var(--color-text);
  min-height: 100vh;
  line-height: 1.6;
}

/* ============================================
   通用组件
   ============================================ */

/* 容器 */
.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 20px;
}

/* 卡片 */
.card {
  background: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  padding: 24px;
  margin-bottom: 20px;
}

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  border: none;
  border-radius: var(--radius-full);
  font-size: 18px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  text-decoration: none;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn:active {
  transform: translateY(0);
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-primary), #FFA500);
  color: white;
}

.btn-secondary {
  background: linear-gradient(135deg, var(--color-secondary), #5DADE2);
  color: white;
}

.btn-success {
  background: linear-gradient(135deg, var(--color-success), #32CD32);
  color: white;
}

.btn-danger {
  background: linear-gradient(135deg, var(--color-danger), #FF69B4);
  color: white;
}

.btn-large {
  padding: 20px 40px;
  font-size: 22px;
}

/* 图标按钮 */
.btn-icon {
  width: 56px;
  height: 56px;
  padding: 0;
  border-radius: 50%;
  font-size: 24px;
}

/* ============================================
   头部
   ============================================ */

.header {
  background: linear-gradient(135deg, var(--color-primary), #FF8C00);
  color: white;
  padding: 24px;
  border-radius: 0 0 var(--radius-lg) var(--radius-lg);
  margin-bottom: 30px;
  box-shadow: var(--shadow-md);
}

.header h1 {
  font-size: 28px;
  text-align: center;
  text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
}

.header-subtitle {
  text-align: center;
  font-size: 16px;
  margin-top: 8px;
  opacity: 0.9;
}

/* ============================================
   主页 - 年级选择
   ============================================ */

.grade-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
  margin-top: 20px;
}

.grade-card {
  background: var(--color-card);
  border-radius: var(--radius-lg);
  padding: 32px;
  text-align: center;
  cursor: pointer;
  transition: all 0.3s ease;
  border: 4px solid transparent;
  position: relative;
  overflow: hidden;
}

.grade-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 8px;
}

.grade-card:nth-child(1)::before { background: linear-gradient(90deg, #FF6B6B, #FF8E53); }
.grade-card:nth-child(2)::before { background: linear-gradient(90deg, #4ECDC4, #45B7AA); }
.grade-card:nth-child(3)::before { background: linear-gradient(90deg, #A29BFE, #6C5CE7); }

.grade-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-primary);
}

.grade-icon {
  font-size: 64px;
  margin-bottom: 16px;
}

.grade-title {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 8px;
}

.grade-desc {
  color: var(--color-text-light);
  font-size: 14px;
}

/* ============================================
   主页 - 分组列表
   ============================================ */

.group-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.compact-group-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(58px, 1fr));
  gap: 10px;
  align-items: center;
}

.compact-group-legend {
  grid-column: 1 / -1;
  display: flex;
  justify-content: center;
  gap: 24px;
  margin-bottom: 6px;
  color: var(--color-text-light);
  font-size: 14px;
}

.compact-group-legend span { display: inline-flex; align-items: center; gap: 6px; }
.legend-dot { width: 14px; height: 14px; border-radius: 50%; display: inline-block; }
.legend-dot.unlearned { background: var(--color-secondary); }
.legend-dot.learned { background: var(--color-success); }

.compact-group-item {
  --group-circle-start: var(--color-secondary);
  --group-circle-end: #5DADE2;
  width: 58px;
  height: 58px;
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  justify-self: center;
  background: linear-gradient(135deg, var(--group-circle-start), var(--group-circle-end));
  color: white;
  font-size: 19px;
  font-weight: 700;
  text-decoration: none;
  box-shadow: var(--shadow-sm);
  transition: transform .18s ease, box-shadow .18s ease;
}

.compact-group-item.completed {
  --group-circle-start: var(--color-success);
  --group-circle-end: #32CD32;
}

.compact-group-item:hover,
.compact-group-item:focus-visible {
  transform: scale(1.1);
  box-shadow: var(--shadow-md);
  outline: 3px solid rgba(255, 179, 71, .45);
}

.learning-failures { max-width: 900px; margin: 28px auto 0; padding: 22px; }
.learning-failures h2 { margin: 0 0 14px; text-align: center; font-size: 24px; }
.learning-fail-empty { text-align: center; color: #777; margin: 10px 0 0; }
.learning-fail-table-wrap { overflow-x: auto; }
.learning-fail-table { width: 100%; border-collapse: collapse; background: #fff; }
.learning-fail-table th, .learning-fail-table td { padding: 11px 12px; border-bottom: 1px solid #eee; text-align: left; }
.learning-fail-table th { color: #E65100; background: #FFF3E0; }
.learning-fail-char { font-size: 25px; font-weight: 700; }
.learning-fail-table a { color: #1689c9; font-weight: 700; }

.group-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--color-card);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  cursor: pointer;
  transition: all 0.2s ease;
  border: 2px solid transparent;
}

.group-item:hover {
  transform: translateX(8px);
  border-color: var(--color-secondary);
  box-shadow: var(--shadow-sm);
}

.group-item.completed {
  border-color: var(--color-success);
  background: linear-gradient(135deg, #F0FFF0, #E8F5E8);
}

.group-info {
  display: flex;
  align-items: center;
  gap: 16px;
}

.group-number {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-secondary), #5DADE2);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: 700;
}

.group-item.completed .group-number {
  background: linear-gradient(135deg, var(--color-success), #32CD32);
}

.group-name {
  font-size: 18px;
  font-weight: 600;
}

.group-progress {
  font-size: 14px;
  color: var(--color-text-light);
}

.group-arrow {
  font-size: 24px;
  color: var(--color-secondary);
}

/* 进度条 */
.progress-bar {
  height: 12px;
  background: #E8E8E8;
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-top: 8px;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--color-success), #32CD32);
  border-radius: var(--radius-full);
  transition: width 0.5s ease;
}

/* 返回按钮 */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--color-text-light);
  text-decoration: none;
  font-size: 16px;
  margin-bottom: 20px;
  padding: 8px 16px;
  border-radius: var(--radius-full);
  background: var(--color-card);
  transition: all 0.2s ease;
}

.back-link:hover {
  background: var(--color-secondary);
  color: white;
}

/* ============================================
   学习页 - 单字显示
   ============================================ */

.char-display {
  text-align: center;
  padding: 40px 20px;
}

.main-char {
  font-family: var(--font-char);
  font-size: 180px;
  line-height: 1;
  color: var(--color-text);
  cursor: pointer;
  transition: all 0.2s ease;
  user-select: none;
  display: inline-block;
  animation: charAppear 0.5s ease;
}

.main-char:hover {
  transform: scale(1.05);
  color: var(--color-primary);
}

.main-char:active {
  transform: scale(0.95);
}

@keyframes charAppear {
  0% { transform: scale(0); opacity: 0; }
  50% { transform: scale(1.1); }
  100% { transform: scale(1); opacity: 1; }
}

.char-pinyin {
  font-size: 36px;
  color: var(--color-secondary);
  margin-top: 16px;
  font-weight: 600;
}

.char-audio-hint {
  font-size: 16px;
  color: var(--color-text-light);
  margin-top: 12px;
}

/* 播放按钮 */
.play-btn {
  width: 72px;
  height: 72px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-primary), #FF8C00);
  border: none;
  color: white;
  font-size: 32px;
  cursor: pointer;
  margin-top: 20px;
  transition: all 0.2s ease;
  box-shadow: var(--shadow-md);
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.play-btn:hover {
  transform: scale(1.1);
  box-shadow: var(--shadow-lg);
}

.play-btn:active {
  transform: scale(0.95);
}

.play-btn.playing {
  animation: pulse 1s infinite;
}

@keyframes pulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(255,179,71,0.7); }
  50% { box-shadow: 0 0 0 20px rgba(255,179,71,0); }
}

/* ============================================
   学习页 - 组词列表
   ============================================ */

.words-section {
  margin-top: 32px;
}

.section-title {
  font-size: 22px;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.section-title::before {
  content: '';
  width: 6px;
  height: 28px;
  background: linear-gradient(180deg, var(--color-primary), #FF8C00);
  border-radius: 3px;
}

.words-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.word-item {
  background: linear-gradient(135deg, #FFF9E6, #FFF5E0);
  border-radius: var(--radius-md);
  padding: 20px;
  cursor: pointer;
  transition: all 0.2s ease;
  border: 2px solid transparent;
}

.word-item:hover {
  border-color: var(--color-primary);
  transform: translateX(8px);
}

.word-item.active {
  border-color: var(--color-primary);
  background: linear-gradient(135deg, #FFE8B3, #FFD98E);
}

.quick-test-panel { margin-top: 24px; text-align: center; border: 2px solid #8bcdf0; }
.quick-test-panel h2 { margin-bottom: 8px; font-size: 23px; }
.quick-test-panel > p { color: var(--color-text-light); margin-bottom: 15px; }
.quick-test-words { display: flex; justify-content: center; flex-wrap: wrap; gap: 12px; margin: 12px 0 18px; }
.quick-test-word { min-width: 92px; padding: 10px 16px; border-radius: 24px; background: #e9f6fd; color: #167bac; font-size: 25px; font-weight: 700; }
.quick-test-word.passed { background: #e7f6e9; color: #2e7d32; }
.quick-test-word.failed { background: #ffebee; color: #c62828; outline: 3px solid #ef5350; }
.quick-test-status { min-height: 26px; margin-top: 14px; font-weight: 700; }
.quick-test-status.recording { color: #e65100; }
.quick-test-status.success { color: #2e7d32; }
.quick-test-status.error { color: #c62828; }
.quick-test-actions { display: flex; justify-content: center; align-items: center; flex-wrap: wrap; gap: 12px; }
.recording-lock { pointer-events: none; opacity: .72; }
.word-item.quick-failed { border: 4px solid #ef5350; background: #fff0f1; box-shadow: 0 0 0 5px rgba(239,83,80,.14); transform: none; }
.word-item.quick-failed .word-text, .word-item.quick-failed .sentence-text { color: #b71c1c; font-weight: 800; }
.word-item.quick-passed { border-color: #66bb6a; }

.word-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.word-text {
  font-family: var(--font-char);
  font-size: 32px;
  font-weight: 700;
  color: var(--color-text);
}

.word-pinyin {
  font-size: 18px;
  color: var(--color-secondary);
  margin-left: 16px;
}

.word-actions {
  display: flex;
  gap: 8px;
  align-items: center;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.word-save-btn {
  min-height: 42px;
  padding: 0 14px;
  border: 2px solid var(--color-primary);
  border-radius: 22px;
  background: white;
  color: #b56500;
  font-weight: 700;
  cursor: pointer;
}

.word-save-btn.saved { background: #e8f5e9; border-color: #43a047; color: #2e7d32; }
.word-record-status { margin-top: 10px; font-size: 14px; }
.notebook-entry-card { display:flex; align-items:center; justify-content:space-between; gap:20px; max-width:760px; margin:0 auto 28px; }
.notebook-entry-card h2 { margin-bottom:6px; }
.notebook-entry-card p { color:var(--color-text-light); }

@media (max-width: 640px) {
  .word-header { align-items:flex-start; gap:12px; }
  .word-actions { max-width:160px; }
  .notebook-entry-card { flex-direction:column; text-align:center; }
}

.word-btn {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: none;
  cursor: pointer;
  font-size: 20px;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}

.word-btn-play {
  background: var(--color-primary);
  color: white;
}

.word-btn-record {
  background: var(--color-danger);
  color: white;
}

.word-btn:hover {
  transform: scale(1.1);
}

/* 例句 */
.sentence-box {
  display: block;
  margin-top: 16px;
  padding-top: 16px;
  border-top: 2px dashed #FFE4B5;
}

.word-item.expanded .sentence-box {
  display: block;
}

.sentence-text {
  font-size: 24px;
  line-height: 2;
  color: var(--color-text);
}

.sentence-pinyin {
  font-size: 16px;
  color: var(--color-text-light);
  margin-top: 8px;
}

.sentence-audio-row {
  margin-top: 12px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.char-hint-panel { max-width:760px; margin:16px auto; padding:18px; text-align:left; background:#fffaf0; border:2px solid #ffca73; border-radius:16px; }
.char-hint-title { display:flex; align-items:center; gap:12px; flex-wrap:wrap; }
.char-hint-title > strong { font-size:38px; }
.char-hint-title > span, .char-hint-pinyin { color:#63899a; }
.char-hint-meaning { margin:12px 0; }
.char-hint-words { display:grid; gap:10px; }
.char-hint-word { padding:12px; background:white; border-radius:12px; border:1px solid #f4ddb8; }
.char-hint-word > div { margin-bottom:5px; }
.char-hint-audio { margin-left:8px; padding:5px 10px; border:0; border-radius:14px; background:#ffae35; color:white; cursor:pointer; }
.char-hint-note { margin-top:12px; color:#9a5d00; font-size:13px; }
.char-box[data-hint-char] { cursor:pointer; }

/* 逐字高亮 */
.char-highlight {
  transition: all 0.2s ease;
  padding: 2px 4px;
  border-radius: 4px;
}

.char-highlight.active {
  background: var(--color-primary);
  color: white;
  transform: scale(1.2);
}

/* 跟读状态 */
.record-status {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  border-radius: var(--radius-full);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
}

.record-status.idle {
  background: #E8E8E8;
  color: #666;
}

.record-status.recording {
  background: var(--color-danger);
  color: white;
  animation: blink 1s infinite;
}

.record-status.success {
  background: var(--color-success);
  color: white;
}

.record-status.error {
  background: #FFB6C1;
  color: #D32F2F;
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.6; }
}

/* ============================================
   学习页 - 关联字
   ============================================ */

.related-section {
  margin-top: 32px;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 16px;
}

.related-item {
  background: linear-gradient(135deg, #E8F4FD, #D4E9F7);
  border-radius: var(--radius-md);
  padding: 20px;
  text-align: center;
  cursor: pointer;
  transition: all 0.2s ease;
  border: 2px solid transparent;
}

.related-item:hover {
  border-color: var(--color-secondary);
  transform: translateY(-4px);
}

.related-char {
  font-family: var(--font-char);
  font-size: 48px;
  font-weight: 700;
  color: var(--color-text);
}

.related-relation {
  font-size: 14px;
  color: var(--color-secondary);
  margin-top: 8px;
  font-weight: 600;
}

.related-note {
  font-size: 12px;
  color: var(--color-text-light);
  margin-top: 4px;
}

/* ============================================
   学习页 - 导航
   ============================================ */

.nav-buttons {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 40px;
  padding-top: 24px;
  border-top: 2px solid #FFE4B5;
}

.nav-progress {
  font-size: 16px;
  color: var(--color-text-light);
}

.nav-progress strong {
  color: var(--color-primary);
  font-size: 24px;
}

/* ============================================
   测验页
   ============================================ */

.quiz-card {
  background: var(--color-card);
  border-radius: var(--radius-lg);
  padding: 40px;
  text-align: center;
  box-shadow: var(--shadow-md);
}

.quiz-word {
  font-family: var(--font-char);
  font-size: 72px;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 16px;
}

.quiz-question {
  font-size: 24px;
  color: var(--color-text-light);
  margin-bottom: 32px;
}

.quiz-options {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  max-width: 600px;
  margin: 0 auto;
}

.quiz-option {
  padding: 20px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, #F5F5F5, #E8E8E8);
  font-size: 28px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  border: 3px solid transparent;
}

.quiz-option:hover:not(.disabled) {
  transform: translateY(-4px);
  box-shadow: var(--shadow-sm);
  border-color: var(--color-secondary);
}

.quiz-option.selected {
  border-color: var(--color-primary);
  background: linear-gradient(135deg, #FFF9E6, #FFE8B3);
}

.quiz-option.correct {
  border-color: var(--color-success);
  background: linear-gradient(135deg, #90EE90, #32CD32);
  color: white;
}

.quiz-option.wrong {
  border-color: var(--color-danger);
  background: linear-gradient(135deg, #FFB6C1, #FF69B4);
  color: white;
}

.quiz-option.disabled {
  cursor: not-allowed;
  opacity: 0.7;
}

/* 测验进度 */
.quiz-progress {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-bottom: 32px;
}

.quiz-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: #E8E8E8;
}

.quiz-dot.current {
  background: var(--color-primary);
  transform: scale(1.3);
}

.quiz-dot.correct {
  background: var(--color-success);
}

.quiz-dot.wrong {
  background: var(--color-danger);
}

/* 测验结果 */
.quiz-result {
  text-align: center;
  padding: 40px;
}

.result-score {
  font-size: 96px;
  font-weight: 700;
  color: var(--color-primary);
  line-height: 1;
}

.result-label {
  font-size: 24px;
  color: var(--color-text-light);
  margin-top: 8px;
}

.result-message {
  font-size: 28px;
  color: var(--color-text);
  margin-top: 24px;
  font-weight: 600;
}

.result-stars {
  font-size: 48px;
  margin-top: 16px;
}

.result-actions {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin-top: 32px;
}

/* ============================================
   动画效果
   ============================================ */

/* 正确反馈动画 */
.correct-burst {
  position: fixed;
  pointer-events: none;
  z-index: 1000;
}

.confetti {
  position: absolute;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  animation: fall 1s ease-out forwards;
}

@keyframes fall {
  0% {
    transform: translateY(0) rotate(0deg);
    opacity: 1;
  }
  100% {
    transform: translateY(200px) rotate(720deg);
    opacity: 0;
  }
}

/* 星星动画 */
@keyframes starPop {
  0% { transform: scale(0) rotate(0deg); }
  50% { transform: scale(1.3) rotate(180deg); }
  100% { transform: scale(1) rotate(360deg); }
}

.star-pop {
  animation: starPop 0.5s ease;
}

/* ============================================
   响应式
   ============================================ */

@media (max-width: 768px) {
  .container {
    padding: 16px;
  }

  .header h1 {
    font-size: 22px;
  }

  .main-char {
    font-size: 120px;
  }

  .char-pinyin {
    font-size: 28px;
  }

  .word-text {
    font-size: 26px;
  }

  .sentence-text {
    font-size: 20px;
  }

  .quiz-options {
    grid-template-columns: 1fr;
  }

  .quiz-option {
    font-size: 24px;
  }

  .quiz-word {
    font-size: 56px;
  }

  .grade-grid {
    grid-template-columns: 1fr;
  }

  .related-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* ============================================
   工具类
   ============================================ */

.text-center { text-align: center; }
.mt-4 { margin-top: 16px; }
.mt-6 { margin-top: 24px; }
.mb-4 { margin-bottom: 16px; }
.hidden { display: none !important; }
.worksheet-builder { max-width: 900px; margin: 24px auto 0; }
.worksheet-controls { background: #fff; border: 2px solid #81D4FA; border-radius: 16px; padding: 18px; }
.worksheet-char-choices { display: flex; flex-wrap: wrap; gap: 8px; margin: 14px 0; }
.worksheet-char-choice { display: inline-flex; align-items: center; gap: 4px; padding: 6px 9px; background: #FFF8E1; border-radius: 8px; }
.worksheet-sheet { width: 18cm; min-height: 26.7cm; margin: 20px auto; padding: 0.4cm 0; background: #fff; color: #222; box-sizing: border-box; box-shadow: 0 3px 16px rgba(0,0,0,.15); }
.worksheet-sheet h2, .worksheet-sheet p { text-align: center; margin: 0 0 0.35cm; }
.worksheet-grid { display: grid; grid-template-columns: repeat(2, 9cm); align-content: start; }
.worksheet-item { display: grid; grid-template-columns: repeat(6, 1.5cm); break-inside: avoid; }
.worksheet-cell { width: 1.5cm; height: 1.5cm; border: 1px dashed #aaa; box-sizing: border-box; display: flex; align-items: center; justify-content: center; font-family: "KaiTi", "STKaiti", "Songti SC", serif; font-size: 1cm; line-height: 1; }
.worksheet-cell.example { border: 1px solid #555; color: #111; }
.worksheet-page-actions { display: flex; justify-content: space-between; align-items: center; gap: 12px; flex-wrap: wrap; margin-bottom: 16px; }
.worksheet-status { max-width: 760px; margin: 0 auto 18px; padding: 12px 16px; background: #FFF8E1; border-radius: 12px; text-align: center; color: #555; }
.review-worksheet-page { width: 20.98cm; height: 29.6cm; margin: 0 auto 24px; padding: 1cm; background: #fff; color: #222; box-sizing: border-box; box-shadow: 0 3px 16px rgba(0,0,0,.15); break-after: page; page-break-after: always; overflow: hidden; }
.review-worksheet-page:last-child { break-after: auto; page-break-after: auto; }
.review-worksheet-heading { height: .8cm; display: flex; align-items: center; justify-content: space-between; border-bottom: 2px solid #555; box-sizing: border-box; font-size: 14px; }
.review-worksheet-rows { padding-top: .05cm; }
.review-worksheet-row { height: 1.33cm; display: grid; grid-template-columns: 5.3cm 13.2cm; align-items: center; break-inside: avoid; page-break-inside: avoid; }
.worksheet-word-info { height: 1.32cm; display: grid; grid-template-columns: 1.05cm 1.45cm 2.65cm; align-items: center; gap: .05cm; padding-right: .05cm; box-sizing: border-box; }
.worksheet-source-char { font-family: "KaiTi", "STKaiti", "Songti SC", serif; font-size: .78cm; text-align: center; }
.worksheet-source-pinyin { font-size: 12px; text-align: center; color: #555; white-space: nowrap; }
.worksheet-source-word { font-size: 15px; padding-left: .1cm; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.worksheet-practice-grid { display: grid; grid-template-columns: repeat(10, 1.32cm); justify-content: end; }
.worksheet-practice-cell { width: 1.32cm; height: 1.32cm; border: 1px solid #999; border-right: 0; box-sizing: border-box; background: linear-gradient(to right, transparent 49%, #ddd 50%, transparent 51%), linear-gradient(to bottom, transparent 49%, #ddd 50%, transparent 51%); }
.worksheet-practice-cell:last-child { border-right: 1px solid #999; }
.pdf-export { width: 21cm; margin: 0; padding: 0; }
.pdf-export .review-worksheet-page { width: 20.98cm; height: 29.6cm; margin: 0; padding: 1cm; box-shadow: none; break-after: auto; page-break-after: auto; }

@media print {
  @page { size: A4; margin: 1.5cm; }
  body * { visibility: hidden !important; }
  #printableWorksheet, #printableWorksheet * { visibility: visible !important; }
  #printableWorksheet { position: absolute; left: 0; top: 0; width: 18cm; min-height: auto; margin: 0; padding: 0; box-shadow: none; }
  .no-print { display: none !important; }
  #groupedWorksheet, #groupedWorksheet * { visibility: visible !important; }
  #groupedWorksheet { position: absolute; left: 0; top: 0; width: 18cm; }
  .review-worksheet-page { margin: 0; box-shadow: none; }
}