:root {
  --primary: #4f46e5;
  --primary-dark: #4338ca;
  --bg: #f3f4f6;
  --card-bg: #ffffff;
  --text: #1f2937;
  --text-light: #6b7280;
  --border: #e5e7eb;
  --success: #10b981;
  --danger: #ef4444;
  --shadow: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-lg: 0 10px 25px rgba(0,0,0,0.12), 0 4px 6px rgba(0,0,0,0.06);
}

* { box-sizing: border-box; margin: 0; padding: 0; -webkit-tap-highlight-color: transparent; }

html, body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  font-size: 16px;
}

.app-header {
  background: linear-gradient(135deg, var(--primary), #6366f1);
  color: #fff;
  padding: 20px 16px 18px;
  text-align: center;
  box-shadow: var(--shadow);
}
.app-header h1 { font-size: 1.5rem; font-weight: 700; letter-spacing: 1px; }
.app-header .subtitle { font-size: 0.8rem; opacity: 0.85; }

.container {
  max-width: 720px;
  margin: 0 auto;
  padding: 14px 12px 80px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.card {
  background: var(--card-bg);
  border-radius: 14px;
  padding: 16px;
  box-shadow: var(--shadow);
}
.card.center { text-align: center; }
.card h2 { font-size: 1.05rem; margin-bottom: 12px; color: var(--text); }
.card h2 .section-sub { font-size: 0.72rem; font-weight: normal; color: var(--text-light); margin-left: 8px; }

/* 可折叠卡片标题 */
.card.collapsible .section-title {
  cursor: pointer;
  user-select: none;
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 12px;
}
.card.collapsible .section-title .caret {
  display: inline-block;
  font-size: 0.7rem;
  color: var(--text-light);
  transition: transform .2s ease;
  line-height: 1;
}
.card.collapsible.collapsed .section-title .caret { transform: rotate(-90deg); }
.card.collapsible.collapsed .section-title { margin-bottom: 0; }
.card h2 .count-badge {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 22px; height: 20px; padding: 0 7px;
  border-radius: 10px; background: var(--primary); color: #fff;
  font-size: 0.75rem; font-weight: normal; line-height: 1;
}
.card.collapsible.collapsed .item-list { display: none; }

textarea, input[type="text"] {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 10px 12px;
  font-size: 0.95rem;
  font-family: inherit;
  background: #fafafa;
  resize: vertical;
}
textarea { margin-bottom: 10px; min-height: 70px; }
input[type="text"] { margin-bottom: 10px; }
textarea:focus, input[type="text"]:focus { outline: none; border-color: var(--primary); background: #fff; }

button {
  border: none;
  border-radius: 10px;
  padding: 10px 18px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  font-family: inherit;
  transition: transform .06s ease, background .2s;
}
button:active { transform: scale(0.97); }
button.primary { background: var(--primary); color: #fff; width: 100%; }
button.primary:hover { background: var(--primary-dark); }
button.secondary {
  background: #fff; color: var(--text-light);
  border: 1px solid var(--border);
  padding: 8px 14px; font-size: 0.85rem; border-radius: 8px;
  flex: 0 0 auto;
}
button.secondary:hover { background: #f3f4f6; color: var(--text); border-color: var(--primary); }
.data-card { padding: 12px 16px; }
.data-card h2 { margin-bottom: 8px; }
.io-row { display: flex; gap: 8px; }
.hidden-file { display: none; }
button.big-primary {
  background: var(--primary); color: #fff;
  font-size: 1.15rem; padding: 14px 36px;
  border-radius: 30px; box-shadow: var(--shadow-lg);
  width: 100%; max-width: 200px;
  position: relative;
}
button.big-primary:hover { background: var(--primary-dark); }
button.big-secondary {
  background: #fff; color: var(--primary);
  border: 2px solid var(--primary);
  font-size: 1.15rem; padding: 12px 36px;
  border-radius: 30px; box-shadow: var(--shadow);
  width: 100%; max-width: 200px;
  position: relative;
}
button.big-secondary:hover { background: #eef2ff; }
.start-row { display: flex; flex-direction: row; justify-content: center; align-items: stretch; gap: 12px; max-width: 420px; margin: 0 auto; }
/* 按钮红点：有需要记的内容时显示 */
.badge-dot {
  position: absolute;
  top: 4px; right: 8px;
  width: 10px; height: 10px;
  border-radius: 50%;
  background: var(--danger);
  display: none;
  border: 2px solid #fff;
  box-shadow: 0 0 0 1px rgba(0,0,0,0.05);
}
.hint { margin-top: 10px; font-size: 0.85rem; color: var(--text-light); min-height: 1.2em; }

.tabs { display: flex; gap: 8px; margin-bottom: 12px; }
.tab {
  flex: 1; background: #f3f4f6; color: var(--text-light);
  padding: 8px 0; border-radius: 8px; font-size: 0.9rem;
}
.tab.active { background: var(--primary); color: #fff; }

.item-list { list-style: none; display: flex; flex-direction: column; gap: 8px; }
.item-list li {
  background: #fafafa;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 12px;
  font-size: 0.95rem;
}
.item-list li .item-content { margin-bottom: 6px; word-break: break-word; white-space: pre-wrap; }
.item-list li .item-meta { font-size: 0.75rem; color: var(--text-light); display: flex; flex-wrap: wrap; gap: 6px; align-items: center; }
.item-list li .item-meta .tag {
  background: #eef2ff; color: var(--primary); padding: 2px 8px; border-radius: 10px;
}
.item-list li .item-meta .date { color: var(--text-light); }

/* 超过4天未添加新词的悬停提示图标 */
.stale-hint {
  display: inline-flex; align-items: center;
  margin-left: 8px; font-size: 0.9rem;
  color: #d97706; cursor: help; line-height: 1;
}
.stale-hint.hidden { display: none; }
/* 忘记复习 badge：仅对有 shift 记录的项显示，悬停看详情 */
.item-list li .item-meta .forget-badge {
  display: inline-flex; align-items: center; gap: 2px;
  background: #fef3c7; color: #92400e;
  padding: 2px 8px; border-radius: 10px;
  font-size: 0.75rem; border: 1px solid #fde68a;
  cursor: help; line-height: 1.4;
  white-space: nowrap;
}
.item-list li .item-meta .forget-badge:hover { background: #fde68a; }
.item-list li.empty { text-align: center; color: var(--text-light); padding: 18px; font-style: italic; background: transparent; border: none; }

.tag-filter { margin-bottom: 12px; display: flex; flex-direction: column; gap: 8px; }
.tag-filter .filter-row {
  display: flex; flex-wrap: wrap; gap: 6px;
  align-items: center;
  border: 1px solid var(--border); border-radius: 10px;
  padding: 6px; background: #fafafa; min-height: 40px;
}
.tag-filter .filter-chip {
  display: inline-flex; align-items: center; gap: 4px;
  background: var(--primary); color: #fff;
  padding: 5px 8px 5px 12px; border-radius: 14px;
  font-size: 0.85rem; cursor: pointer; user-select: none;
}
.tag-filter .filter-chip .filter-x { font-size: 11px; opacity: 0.85; }
.tag-filter .filter-chip:hover .filter-x { opacity: 1; }
.tag-filter .filter-add {
  display: inline-flex; align-items: center; justify-content: center;
  width: 32px; height: 32px; border-radius: 50%;
  background: #fff; color: var(--text-light);
  border: 1px dashed var(--border); font-size: 1.2rem;
  cursor: pointer; line-height: 1; user-select: none;
}
.tag-filter .filter-add:hover { background: #f3f4f6; color: var(--primary); border-color: var(--primary); }

/* 搜索模式切换页签 */
.search-tabs { display: flex; gap: 8px; margin-bottom: 12px; }
.search-tab {
  border: 1px solid var(--border); background: #fff; color: var(--text-light);
  border-radius: 18px; padding: 6px 14px; font-size: 0.85rem;
  cursor: pointer; font-family: inherit; transition: all .15s;
}
.search-tab:hover { color: var(--primary); border-color: var(--primary); }
.search-tab.active { background: var(--primary); color: #fff; border-color: var(--primary); }

/* 按当前模式隐藏非激活的搜索区 */
#tag-filter.hidden { display: none; }
.exact-search-row.hidden { display: none; }

/* 精确搜索行 */
.exact-search-row { display: flex; gap: 8px; margin-bottom: 12px; }
.exact-search-row .exact-search {
  flex: 1; min-width: 0;
  border: 1px solid var(--border); border-radius: 10px;
  padding: 10px 12px; font-size: 0.95rem; outline: none; font-family: inherit;
}
.exact-search-row .exact-search:focus { border-color: var(--primary); }
.exact-search-row .secondary { flex-shrink: 0; }

.tag-filter .filter-picker {
  display: flex; flex-direction: column; gap: 6px;
  border: 1px solid var(--border); border-radius: 10px;
  padding: 8px; background: #fff;
}
.tag-filter .filter-picker.hidden { display: none; }
.tag-filter .filter-input {
  border: 1px solid var(--border); border-radius: 8px;
  padding: 8px 10px; font-size: 0.9rem; font-family: inherit;
  background: #fafafa; color: var(--text); outline: none;
}
.tag-filter .filter-input:focus { border-color: var(--primary); background: #fff; }
.tag-filter .filter-select {
  border: 1px solid var(--border); border-radius: 8px;
  padding: 4px; font-size: 0.9rem; font-family: inherit;
  background: #fafafa; color: var(--text); outline: none;
  min-height: 80px;
}
.tag-filter .filter-select:focus { border-color: var(--primary); }
.tag-filter .filter-select option { padding: 6px 8px; }

/* 弹窗 */
.modal {
  position: fixed; inset: 0;
  background: rgba(0,0,0,0.45);
  display: flex; align-items: center; justify-content: center;
  z-index: 1000; padding: 16px;
}
.modal.hidden { display: none; }
.modal-card {
  background: #fff; border-radius: 16px; padding: 22px;
  width: 100%; max-width: 420px; box-shadow: var(--shadow-lg);
  display: flex; flex-direction: column; gap: 14px;
}
.modal-progress { text-align: center; font-size: 0.8rem; color: var(--text-light); }
.modal-content {
  font-size: 1.1rem; line-height: 1.6; text-align: center;
  min-height: 80px; padding: 16px; background: #f9fafb; border-radius: 10px;
  word-break: break-word; white-space: pre-wrap;
}
.modal-tags { display: flex; flex-wrap: wrap; gap: 6px; justify-content: center; }
.modal-tags .tag { background: #eef2ff; color: var(--primary); padding: 3px 10px; border-radius: 10px; font-size: 0.75rem; }
.modal-actions { display: flex; gap: 12px; }
.modal-actions button { flex: 1; padding: 14px 0; font-size: 1rem; border-radius: 12px; }
.modal-actions .check { background: var(--success); color: #fff; }
.modal-actions .cross { background: var(--danger); color: #fff; }
.modal-actions .readd { background: #f59e0b; color: #fff; }
.modal-actions .readd:hover { background: #d97706; }
.close-btn { background: #f3f4f6; color: var(--text-light); width: 100%; padding: 8px; font-size: 0.85rem; }

/* toast */
.toast {
  position: fixed; bottom: 24px; left: 50%; transform: translateX(-50%);
  background: rgba(31,41,55,0.95); color: #fff;
  padding: 10px 18px; border-radius: 24px; font-size: 0.85rem;
  z-index: 2000; box-shadow: var(--shadow-lg); max-width: 90vw; text-align: center;
}
.toast.hidden { display: none; }

/* 列表项：编辑按钮 + 记忆按钮 */
.item-list li .item-actions { margin-top: 8px; text-align: right; display: flex; gap: 6px; justify-content: flex-end; }
.item-list li .item-actions button {
  background: #f3f4f6; color: var(--text-light); padding: 5px 12px;
  font-size: 0.8rem; border-radius: 8px; font-weight: 500;
}
.item-list li .item-actions button[data-memorize-id] {
  background: #eef2ff; color: var(--primary);
}
.item-list li .item-actions button[data-memorize-id]:hover { background: #c7d2fe; }
.item-list li .item-actions button[data-edit-id]:hover { background: #e5e7eb; color: var(--text); }

/* 出题模式切换 */
/* 设置行：左边标签 + 右边控件，grid 布局对齐 */
.setting-row {
  display: grid;
  grid-template-columns: 80px 1fr;
  align-items: center;
  gap: 12px;
  margin-bottom: 10px;
}
.setting-row:last-child { margin-bottom: 0; }
.setting-label {
  font-size: 0.85rem; color: var(--text-light);
  text-align: right;
}

.mode-switch {
  display: flex; gap: 0;
  border: 1px solid var(--border); border-radius: 10px;
  overflow: hidden; max-width: 360px;
}
.mode-option {
  flex: 1; display: flex; align-items: center; justify-content: center;
  cursor: pointer; padding: 8px 0; font-size: 0.9rem;
  background: #f9fafb; color: var(--text-light);
  transition: background .15s, color .15s;
  border-right: 1px solid var(--border);
}
.mode-option:last-child { border-right: none; }
.mode-option input { display: none; }
.mode-option:has(input:checked) {
  background: var(--primary); color: #fff; font-weight: 600;
}

/* 阶段时间轴 */
.stages {
  display: flex; flex-wrap: wrap; gap: 6px;
  margin-top: 8px; padding: 6px 0;
}
.stage {
  display: inline-flex; align-items: center; gap: 4px;
  padding: 3px 8px; border-radius: 8px;
  background: #f3f4f6; color: var(--text-light);
  font-size: 0.7rem; line-height: 1.4;
  border: 1px solid transparent;
}
.stage .stage-label { font-weight: 600; }
.stage .stage-date { color: var(--text-light); }
.stage .stage-mark { font-weight: bold; }
.stage.done { background: #ecfdf5; color: #047857; border-color: #a7f3d0; }
.stage.done .stage-date { color: #047857; }
.stage.current { background: #eef2ff; color: var(--primary); border-color: #c7d2fe; font-weight: 600; }
.stage.current .stage-date { color: var(--primary); }
.stage.today { box-shadow: 0 0 0 2px #fbbf24; }
.item-list li .item-actions button {
  background: #f3f4f6; color: var(--text-light); padding: 5px 12px;
  font-size: 0.8rem; border-radius: 8px; font-weight: 500;
}
.item-list li .item-actions button:hover { background: #e5e7eb; color: var(--text); }
.item-list li.hidden-peek { opacity: 0.55; }

/* 编辑弹窗 */
.edit-card { max-width: 520px; gap: 12px; }
.edit-card textarea { margin-bottom: 0; }
.edit-section { display: flex; flex-direction: column; gap: 6px; }
.edit-label { font-size: 0.85rem; color: var(--text-light); display: flex; justify-content: space-between; align-items: center; gap: 8px; }
.edit-label-hint { font-size: 0.72rem; color: var(--text-light); opacity: 0.8; font-weight: normal; }

/* chip 容器（标签 / 条目） */
.chip-box {
  display: flex; flex-wrap: wrap; gap: 8px;
  min-height: 44px; padding: 8px;
  background: #fafafa; border: 1px dashed var(--border);
  border-radius: 10px; align-items: center;
}
.chip {
  display: inline-flex; align-items: center; gap: 6px;
  background: #eef2ff; color: var(--primary);
  padding: 6px 8px 6px 12px; border-radius: 18px;
  font-size: 0.95rem; user-select: none;
  cursor: pointer; line-height: 1.4;
  min-height: 32px;
}
.chip.relation { background: #ecfdf5; color: #047857; }
.chip.relation.hidden-rel { background: #fef3c7; color: #92400e; opacity: 0.85; }
.chip .chip-x {
  display: inline-flex; align-items: center; justify-content: center;
  width: 20px; height: 20px; border-radius: 50%;
  background: rgba(0,0,0,0.08); color: inherit; font-size: 13px;
  margin-left: 2px;
}
.chip .chip-x:hover { background: rgba(220,38,38,0.2); color: #dc2626; }
.chip .eye {
  display: inline-flex; align-items: center; justify-content: center;
  width: 20px; height: 20px; font-size: 14px;
  margin-right: 2px; opacity: 0.8;
}
.chip-add {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 36px; height: 32px; padding: 0 10px;
  background: #fff; color: var(--text-light);
  border: 1px dashed var(--border); border-radius: 18px;
  font-size: 1.3rem; cursor: pointer; line-height: 1;
}
.chip-add:hover { background: #f3f4f6; color: var(--primary); border-color: var(--primary); }
.chip-input {
  border: 1px solid var(--primary); background: #fff;
  border-radius: 18px; padding: 6px 12px;
  font-size: 0.95rem; min-width: 120px; outline: none;
  font-family: inherit; height: 32px;
}

/* 近期常用标签建议行 */
.tag-suggest-row {
  flex-basis: 100%;
  display: flex; flex-wrap: wrap; align-items: center; gap: 6px;
  padding-top: 6px; border-top: 1px dashed var(--border);
}
.tag-suggest-label { font-size: 0.75rem; color: var(--text-light); flex-shrink: 0; }
.tag-suggest {
  display: inline-flex; align-items: center;
  padding: 3px 10px; border-radius: 14px;
  background: #fff; color: var(--text-light);
  border: 1px solid var(--border);
  font-size: 0.82rem; cursor: pointer; line-height: 1.4;
  user-select: none; transition: all .15s;
}
.tag-suggest:hover { background: #eef2ff; color: var(--primary); border-color: var(--primary); }

/* 开关 toggle */
.toggle-row {
  display: flex; justify-content: space-between; align-items: center;
  font-size: 0.9rem; color: var(--text); cursor: pointer;
  padding: 4px 0;
}
.toggle {
  width: 44px; height: 24px; border-radius: 12px;
  background: #d1d5db; position: relative; cursor: pointer;
  transition: background .2s; flex-shrink: 0;
}
.toggle .knob {
  width: 20px; height: 20px; border-radius: 50%;
  background: #fff; position: absolute; top: 2px; left: 2px;
  transition: left .2s; box-shadow: 0 1px 2px rgba(0,0,0,0.2);
}
.toggle.on { background: var(--success); }
.toggle.on .knob { left: 22px; }

/* 关联区域（记忆弹窗里） */
.modal-relations {
  display: flex; flex-direction: column; gap: 10px;
  align-items: center; padding: 8px 0;
}
/* 生字大字号楷体 */
.quiz-word {
  font-family: "KaiTi", "STKaiti", "AR PL UKai", "楷体", "FangSong", "STFangsong", serif;
  font-size: 5rem;
  line-height: 1.2;
  color: var(--text);
  text-align: center;
  padding: 12px 8px;
  min-height: 96px;
  display: flex; align-items: center; justify-content: center;
  word-break: break-all;
}
.quiz-word.masked {
  font-size: 1rem;
  color: var(--text-light);
  font-style: italic;
  font-family: inherit;
  min-height: 96px;
}
.quiz-pinyin {
  font-size: 2rem;
  line-height: 1.3;
  color: var(--primary);
  text-align: center;
  background: #eef2ff;
  border: 1px solid #c7d2fe;
  border-radius: 10px;
  padding: 8px 18px;
  letter-spacing: 1px;
  min-width: 80px;
  display: inline-block;
}
.quiz-pinyin.masked {
  font-size: 1rem;
  color: var(--text-light);
  font-style: italic;
  background: transparent;
  border-color: transparent;
  padding: 8px;
}

/* 编辑弹窗：生字表单 */
.entry-form { display: flex; flex-direction: column; gap: 10px; }
.entry-row {
  display: flex; align-items: center; gap: 8px;
}
.entry-row .entry-label {
  flex: 0 0 50px;
  font-size: 0.85rem; color: var(--text-light);
  text-align: right;
}
.entry-row .entry-input {
  flex: 1;
  border: 1px solid var(--border); border-radius: 8px;
  padding: 8px 10px; font-size: 1rem; font-family: "KaiTi","STKaiti","楷体",serif;
  background: #fafafa; color: var(--text); min-width: 0;
}
.entry-row .entry-input:focus { outline: none; border-color: var(--primary); background: #fff; }
.entry-row .entry-input[readonly] {
  background: #f3f4f6; color: var(--text-light); cursor: default;
}
.entry-row .entry-input[readonly]:focus { border-color: var(--border); background: #f3f4f6; }

/* 拼音声调纠错区 */
.pinyin-tweak {
  margin-top: 2px;
  padding: 8px 10px 10px 58px; /* 58px 左缩进对齐拼音输入框 */
  background: #fafafa;
  border: 1px solid var(--border);
  border-radius: 8px;
  display: flex; flex-direction: column; gap: 6px;
}
.pinyin-tweak.hidden { display: none; }
.pinyin-tweak-label {
  font-size: 0.72rem; color: var(--text-light); opacity: 0.85;
}
.pinyin-syllables {
  display: flex; flex-wrap: wrap; gap: 6px; align-items: center;
}
.pinyin-syl {
  display: inline-flex; align-items: center; justify-content: center;
  background: #eef2ff; color: var(--primary);
  padding: 5px 12px; border-radius: 14px;
  font-size: 1rem; cursor: pointer; user-select: none;
  border: 1px solid transparent;
  transition: background .15s, border-color .15s;
  min-width: 36px; line-height: 1.4;
}
.pinyin-syl:hover { background: #e0e7ff; border-color: #c7d2fe; }
.pinyin-syl.active { background: var(--primary); color: #fff; border-color: var(--primary-dark); }
.pinyin-syl.non-han { background: #f3f4f6; color: var(--text-light); cursor: default; }
.pinyin-syl.non-han:hover { background: #f3f4f6; border-color: transparent; }

/* 声调选择浮层（内联展开在音节按钮后） */
.pinyin-syl-pop {
  display: inline-flex; align-items: center; gap: 4px;
  padding: 4px 6px; border-radius: 14px;
  background: #fff; border: 1px solid var(--border);
  box-shadow: var(--shadow);
}
.pinyin-tone-opt {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 4px 10px; border-radius: 10px;
  font-size: 0.95rem; cursor: pointer; user-select: none;
  background: #f3f4f6; color: var(--text); line-height: 1.4;
  min-width: 30px;
}
.pinyin-tone-opt:hover { background: #eef2ff; color: var(--primary); }
.pinyin-tone-opt.current { background: var(--primary); color: #fff; }
.pinyin-tone-opt.tone-0 { font-size: 0.82rem; color: var(--text-light); }
.pinyin-tone-opt.tone-0.current { color: #fff; }
.pinyin-tone-opt .tone-num {
  margin-left: 4px;
  font-size: 0.65rem;
  opacity: 0.7;
  font-weight: 600;
}
.pinyin-tone-opt.current .tone-num { opacity: 1; }

/* 题型提示标签（在 modal-progress-text 内） */
.modal-progress-text .quiz-tag {
  display: inline-block;
  background: #fef3c7; color: #92400e;
  padding: 1px 8px; border-radius: 6px;
  font-size: 0.8rem; margin-left: 4px;
}

/* 对照按钮 */
.modal-actions .peek {
  background: #f3f4f6; color: var(--text); flex: 0 0 auto;
  padding: 14px 16px; font-size: 0.9rem;
}
.modal-actions .peek:hover { background: #e5e7eb; }

@media (min-width: 768px) {
  .app-header { padding: 28px; }
  .app-header h1 { font-size: 1.8rem; }
  .container { padding: 20px 16px 100px; }
  .card { padding: 20px; }
  .edit-card { padding: 24px; }
}