/* ========== 直通高分雅思 · 小资学习风 ========== */
:root {
  --bg: #f7f1e8;               /* 暖米色纸感底 */
  --bg-grad: linear-gradient(160deg, #f9f4ec 0%, #f4ecdf 55%, #efe6d6 100%);
  --card: #fffdf8;             /* 奶白卡片 */
  --ink: #3d362e;              /* 暖墨色正文 */
  --muted: #948a7b;            /* 燕麦灰 */
  --line: #eadfcd;             /* 浅驼色描边 */
  --primary: #a9714b;          /* 焦糖棕 */
  --primary-dark: #8a5a38;
  --primary-soft: #f6ebdd;
  --accent: #c9a227;           /* 哑金 */
  --sage: #8ba085;             /* 抹茶灰绿 */
  --ielts: #b0533c;            /* 陶土红（雅思常考义） */
  --ok: #7e9c6f;
  --danger: #b0533c;
  --radius: 14px;
  --shadow: 0 1px 2px rgba(90,70,50,.06), 0 10px 28px rgba(90,70,50,.09);
  --serif: "Noto Serif SC", "Songti SC", Georgia, "Times New Roman", serif;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
[hidden] { display: none !important; }   /* 防止 display:flex 等规则覆盖 hidden 属性 */
html, body { height: 100%; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Segoe UI", system-ui, sans-serif;
  background: var(--bg-grad); color: var(--ink); line-height: 1.65;
  background-attachment: fixed;
}
h1, h2, h3 { font-family: var(--serif); letter-spacing: .02em; }
h1 { font-size: 23px; } h2 { font-size: 20px; } h3 { font-size: 16px; }
.muted { color: var(--muted); }
.small { font-size: 12px; }
.row { display: flex; align-items: center; }
.gap { gap: 10px; }
.items-center { align-items: center; }

/* 顶栏：奶白纸面 + 细金线 */
.topbar {
  position: sticky; top: 0; z-index: 50;
  display: flex; justify-content: space-between; align-items: center;
  padding: 10px 22px;
  background: rgba(255,253,248,.92); backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
  box-shadow: 0 1px 0 rgba(201,162,39,.18), 0 4px 18px rgba(90,70,50,.05);
}
.logo-wrap { cursor: pointer; }
.logo { font-family: var(--serif); font-size: 20px; font-weight: 700; color: var(--primary-dark); }
.logo-en { font-size: 11px; color: var(--accent); letter-spacing: .14em; margin-left: 8px; font-weight: 500; font-style: italic; }
.logo-sub { font-size: 11px; color: var(--muted); letter-spacing: .18em; }
.ai-badge {
  font-size: 12px; color: var(--primary-dark); background: var(--primary-soft);
  border: 1px solid #e7d3b8; padding: 3px 12px; border-radius: 99px; white-space: nowrap;
}
.topbar-right { display: flex; gap: 8px; align-items: center; }

main { max-width: 1000px; margin: 0 auto; padding: 24px 16px 90px; }
.screen { animation: fadeIn .3s ease; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(8px);} to { opacity: 1; transform: none;} }

/* 按钮：圆角软糖 */
.btn {
  border: 1px solid var(--line); background: var(--card); color: var(--ink);
  border-radius: 999px; padding: 7px 16px; font-size: 14px; cursor: pointer;
  transition: all .18s ease;
}
.btn:hover:not(:disabled) { border-color: var(--primary); color: var(--primary-dark); transform: translateY(-1px); box-shadow: 0 4px 10px rgba(169,113,75,.15); }
.btn:disabled { opacity: .4; cursor: not-allowed; }
.btn.primary { background: linear-gradient(135deg, #b07a52, #96603c); border-color: transparent; color: #fff; }
.btn.primary:hover:not(:disabled) { background: linear-gradient(135deg, #a06c46, #85512f); color: #fff; }
.btn.ghost { background: transparent; }
.btn.danger { color: var(--danger); }
.btn.chip { padding: 4px 13px; font-size: 13px; }

/* 卡片：奶油纸 + 金色细顶线 */
.card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow); padding: 26px; position: relative; overflow: hidden;
}
.card::before {
  content: ""; position: absolute; top: 0; left: 0; right: 0; height: 3px;
  background: linear-gradient(90deg, transparent, var(--accent) 30%, var(--primary) 60%, transparent);
  opacity: .55;
}
.card-lite {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 12px 18px; display: flex; flex-wrap: wrap; gap: 8px; align-items: center;
  box-shadow: 0 1px 2px rgba(90,70,50,.05);
}
/* 播放控件吸顶：生词列表滚动到下方时，通读/暂停/停止按钮跟随显示，随时可停 */
.play-controls {
  position: sticky; top: 8px; z-index: 50;
  background: var(--card);
  box-shadow: 0 4px 14px rgba(90,70,50,.16);
  border: 1px solid var(--line);
}

/* 输入向导 */
.step-badge {
  display: inline-block; background: var(--primary-soft); color: var(--primary-dark);
  font-size: 12px; letter-spacing: 1px; padding: 3px 12px; border-radius: 99px; margin-bottom: 10px;
}
.sample-box {
  background: #fbf6ec; border: 1px dashed #d9bd97; border-radius: 10px;
  padding: 10px 14px; font-size: 13px; color: #6b5d49; margin: 10px 0; line-height: 1.9;
  font-family: Georgia, "Times New Roman", serif;
}
/* 确认屏 */
.field-label { display: block; font-size: 13px; font-weight: 600; margin: 14px 0 6px; color: var(--primary-dark); }
.text-input {
  width: 100%; padding: 9px 14px; border: 1px solid var(--line); border-radius: 10px;
  font-size: 14px; font-family: inherit; background: #fffdf8;
}
.text-input:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(169,113,75,.12); }
.confirm-textarea {
  width: 100%; min-height: 340px; padding: 16px; border: 1px solid var(--line);
  border-radius: 10px; font-size: 15.5px; line-height: 2; font-family: Georgia, "Times New Roman", serif;
  resize: vertical; background: #fffdf8; color: var(--ink);
}
.confirm-textarea:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(169,113,75,.12); }
.screen .row { margin-top: 18px; }

/* 学习页 Tabs：书签式导航 */
.study-tabs {
  display: flex; gap: 6px; flex-wrap: wrap; margin-bottom: 18px;
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 9px;
  box-shadow: var(--shadow);
  position: sticky; top: 72px; z-index: 40;
}
.tab {
  flex: 1; min-width: 130px; border: none; background: transparent; padding: 10px 8px;
  border-radius: 999px; font-size: 14px; cursor: pointer; color: var(--muted); white-space: nowrap;
  transition: all .18s;
}
.tab:hover { color: var(--primary-dark); background: var(--primary-soft); }
.tab.active { background: linear-gradient(135deg, #b07a52, #96603c); color: #fff; font-weight: 600; box-shadow: 0 4px 12px rgba(150,96,60,.3); }

.panel-head {
  display: flex; justify-content: space-between; align-items: flex-start;
  gap: 12px; flex-wrap: wrap; margin-bottom: 16px;
}
.mode-switch { display: flex; align-items: center; gap: 6px; flex-wrap: wrap; }

/* ===== 读一读 ===== */
.para-module {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow); padding: 18px 20px; margin-bottom: 14px; position: relative;
}
.para-module::before {
  content: ""; position: absolute; left: 0; top: 12px; bottom: 12px; width: 3px;
  background: linear-gradient(180deg, var(--accent), transparent); border-radius: 99px; opacity: .5;
}
.para-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: 10px; gap: 8px; flex-wrap: wrap; }
.para-badge {
  font-family: var(--serif); font-size: 12px; color: var(--primary-dark); background: var(--primary-soft);
  padding: 2px 12px; border-radius: 99px; font-weight: 600; border: 1px solid #e7d3b8;
}
.para-modes { display: flex; gap: 6px; }
.para-text { font-family: Georgia, "Times New Roman", serif; font-size: 17px; line-height: 1.7; color: #35302a; }
.mode-original { font-size: 18px; line-height: 2.1; }

/* 详细模式：词块 上音标 / 中单词 / 下词义（音标完整显示，空间不够自动加宽词块） */
.detail-line { margin-bottom: 4px; }
.tok {
  display: inline-flex; flex-direction: column; align-items: center;
  vertical-align: bottom; margin: 2px 5px 6px; padding: 1px 4px; border-radius: 6px;
  cursor: pointer;
}
.tok:hover { background: var(--primary-soft); }
.tok .t-ph { font-size: 10px; color: #b08d55; line-height: 1.25; min-height: 13px; white-space: nowrap; }
.tok .t-w { font-size: 16px; line-height: 1.35; white-space: nowrap; }
.tok .t-mn { font-size: 10px; color: var(--muted); line-height: 1.3; min-height: 13px;
  max-width: 170px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
/* 词组（For example 等）与普通单词视觉完全一致：不再加粗、变色或加虚线，只保留可点击 */
.tok.speaking { background: #f3e3b8; box-shadow: 0 0 0 2px var(--accent); }
.tok.loading .t-mn { color: #cbb894; }
.tok.loc-target { background: #f3e3b8; box-shadow: 0 0 0 2px var(--accent); }
.zh-run { color: #55503f; }
.punct { display: inline; }

/* 点读模式（点击单词弹释义卡） */
.hover-text .w { cursor: pointer; border-radius: 4px; padding: 0 1px; transition: background .12s; }
.hover-text .w:hover { background: var(--primary-soft); color: var(--primary-dark); }
.hover-text .w.active { background: #f3e3b8; color: var(--primary-dark); }
/* .w.phrase 不加任何特殊样式，词组与正文同色同字重 */
.hover-text .w.speaking { background: #f3e3b8; }

/* 浮动提示框：奶白便签 */
#tooltip {
  position: absolute; z-index: 100; max-width: 340px;
  background: #fffdf8; border: 1px solid #dcc9a8; border-radius: 12px;
  box-shadow: 0 10px 32px rgba(90,70,50,.22); padding: 12px 14px; font-size: 13px;
  animation: fadeIn .12s ease;
}
#tooltip .tt-close {
  position: absolute; top: 4px; right: 6px; border: none; background: none;
  font-size: 15px; line-height: 1; color: var(--muted); cursor: pointer; padding: 3px 5px; border-radius: 6px;
}
#tooltip .tt-close:hover { color: var(--primary-dark); background: var(--primary-soft); }
#tooltip::before {
  content: ""; position: absolute; top: 0; left: 14px; right: 14px; height: 2px;
  background: linear-gradient(90deg, var(--accent), transparent); border-radius: 99px;
}
#tooltip .tt-word { font-family: var(--serif); font-size: 17px; font-weight: 700; color: var(--primary-dark); }
#tooltip .tt-ph { color: #b08d55; margin-left: 8px; font-size: 13px; }
#tooltip .tt-pos { color: var(--sage); font-size: 12px; margin-left: 8px; }
#tooltip .tt-sec { margin-top: 8px; }
#tooltip .tt-label { font-size: 11px; color: var(--muted); margin-bottom: 2px; }
#tooltip .tag {
  display: inline-block; font-size: 10px; padding: 0 7px; border-radius: 99px; margin-right: 4px;
  vertical-align: 1px;
}
.tag.ielts { background: #f6e2da; color: var(--ielts); }
.tag.rare { background: #efe9dd; color: var(--muted); }
.tag.ctx { background: var(--primary-soft); color: var(--primary-dark); }
#tooltip .tt-actions { margin-top: 10px; display: flex; gap: 8px; }
#tooltip .btn { padding: 4px 12px; font-size: 12px; }
#tooltip .tt-morph {
  font-size: 12px; color: #7a6142; background: #f7efe3; border: 1px solid #e8dcc4;
  border-radius: 8px; padding: 4px 9px; display: inline-block; line-height: 1.5;
}
/* 词典式义项列表 */
#tooltip .tt-sense { display: flex; gap: 6px; padding: 3px 0; font-size: 13px; line-height: 1.5; align-items: baseline; }
#tooltip .tt-sense + .tt-sense { border-top: 1px dashed #efe6d6; }
#tooltip .tt-sense .sn { color: #a9714b; font-weight: 600; min-width: 18px; }
#tooltip .tt-sense .sp { color: #8a7355; font-style: italic; min-width: 30px; font-size: 12px; }
#tooltip .btn.added, #tooltip .btn:disabled {
  background: #e8f3ea; color: #4c7a52; border-color: #cfe3d2; cursor: default; opacity: 1;
}

/* ===== 翻译 ===== */
.tr-block { margin-bottom: 16px; }
.tr-box {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow); padding: 16px 20px;
}
.tr-box h3 { color: var(--primary-dark); margin-bottom: 8px; }
.sentence-pair {
  display: grid; grid-template-columns: 34px 1fr; gap: 4px 10px;
  padding: 10px 4px; border-bottom: 1px dashed #e2d5bd;
}
.sentence-pair:last-child { border-bottom: none; }
.s-no { font-size: 12px; color: var(--accent); font-weight: 700; padding-top: 3px; font-family: var(--serif); }
.s-src { cursor: pointer; font-family: Georgia, serif; font-size: 15px; }
.s-src:hover { color: var(--primary-dark); }
.s-dst { color: #5b5348; font-size: 14px; grid-column: 2; }
.para-tag { font-size: 11px; color: var(--sage); margin-left: 6px; }

/* ===== 生词本 ===== */
.empty-tip {
  text-align: center; color: var(--muted); background: var(--card); border: 1px dashed #d9bd97;
  border-radius: var(--radius); padding: 36px; margin-top: 14px;
}
.vocab-list { display: flex; flex-direction: column; gap: 10px; margin-top: 14px; }
.vocab-item {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: 0 1px 2px rgba(90,70,50,.05); padding: 13px 18px; display: flex; gap: 12px; align-items: flex-start;
  transition: all .18s;
}
.vocab-item.current { border-color: var(--accent); box-shadow: 0 0 0 2px var(--accent), 0 6px 18px rgba(201,162,39,.18); }
.v-main { flex: 1; }
.v-word { font-family: var(--serif); font-size: 17px; font-weight: 700; color: var(--primary-dark); }
.v-ph { color: #b08d55; margin-left: 8px; font-size: 13px; }
.v-pos { color: var(--sage); font-size: 12px; margin-left: 8px; }
.v-mn { margin-top: 4px; font-size: 13px; }
.v-src { margin-top: 6px; font-size: 12px; color: var(--muted); font-style: italic; }
.v-ex { margin-top: 6px; font-size: 12px; color: #5b5348; background: #faf4e8; border-radius: 8px; padding: 6px 10px; }
.v-ex b { color: var(--primary-dark); }
.v-ex .v-ex-zh, .v-ex-zh { margin-top: 3px; font-size: 12px; color: #8a7355; }
.v-ex-zh::before { content: "译："; color: #b08d55; }
.v-btns { display: flex; flex-direction: column; gap: 6px; }
.v-btns .btn { padding: 3px 12px; font-size: 12px; }

/* ===== 语法 ===== */
.grammar-module {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow); padding: 16px 20px; margin-bottom: 14px;
}
.g-point { border-top: 1px dashed #e2d5bd; padding: 12px 0; }
.g-point:first-of-type { border-top: none; }
.g-head { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.g-no {
  display: inline-flex; align-items: center; justify-content: center;
  width: 22px; height: 22px; border-radius: 50%; flex: none;
  background: var(--primary-soft, #f3e8d8); color: var(--primary-dark, #8a5a32);
  font-size: 12px; font-weight: 700;
}
.g-name { font-family: var(--serif); font-weight: 700; color: var(--primary-dark); font-size: 15px; }
.g-dup {
  display: inline-block; margin-left: 8px; font-size: 11px; color: var(--muted);
  background: #efe9dd; padding: 1px 10px; border-radius: 99px;
}
.g-example { margin-top: 6px; font-family: Georgia, serif; font-size: 14px; color: #35302a; background: var(--primary-soft); border-radius: 8px; padding: 6px 12px; }
.g-row { margin-top: 6px; font-size: 13px; }
.g-row .k { color: var(--accent); margin-right: 6px; font-weight: 600; }
.g-row.warn .k { color: var(--ielts); }
.g-row.tip { color: var(--sage); }

/* 骨架屏 */
.skeleton { background: linear-gradient(90deg,#f1e9da 25%,#e7dcc7 50%,#f1e9da 75%); background-size: 200% 100%;
  animation: shimmer 1.3s infinite; border-radius: 10px; }
@keyframes shimmer { to { background-position: -200% 0; } }
.sk-line { height: 16px; margin: 10px 0; }
.sk-block { height: 110px; margin-bottom: 12px; }

/* 弹窗 & Toast */
.modal {
  position: fixed; inset: 0; z-index: 200; background: rgba(61,54,46,.4);
  backdrop-filter: blur(3px);
  display: flex; align-items: center; justify-content: center; padding: 16px;
}
.modal-card { background: #fffdf8; border-radius: 16px; padding: 24px; width: 100%; max-width: 460px; box-shadow: 0 24px 70px rgba(61,54,46,.3); }
.modal-card .row { margin-top: 16px; }
.toast {
  position: fixed; bottom: 30px; left: 50%; transform: translateX(-50%); z-index: 300;
  background: #3d362e; color: #f5eee2; padding: 9px 20px; border-radius: 99px; font-size: 13px;
  box-shadow: 0 8px 24px rgba(61,54,46,.3); animation: fadeIn .2s;
}

/* ===== 首页：已加载课文列表 ===== */
.library-list { display: flex; flex-direction: column; gap: 10px; margin-top: 4px; }
.lib-item {
  display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap;
  background: #fbf6ec; border: 1px solid var(--line); border-radius: 12px; padding: 12px 16px;
  transition: border-color .18s, box-shadow .18s;
}
.lib-item:hover { border-color: #d9bd97; box-shadow: 0 4px 12px rgba(169,113,75,.10); }
.lib-item.active { border-color: var(--primary); background: var(--primary-soft); }
.lib-main { min-width: 0; flex: 1; }
.lib-title { font-family: var(--serif); font-size: 17px; font-weight: 700; color: var(--primary-dark); }
.lib-meta { font-size: 11.5px; color: var(--muted); margin-top: 3px; }
.lib-badge { display: inline-block; font-size: 11px; color: var(--ok); background: #eef3e9; border-radius: 99px; padding: 1px 9px; margin-left: 6px; }
.lib-badge.pending { color: #a9714b; background: #f6ebdd; }
.lib-actions { display: flex; gap: 8px; }
.empty-tip { background: #fbf6ec; border: 1px dashed #d9bd97; border-radius: 10px; padding: 14px 16px; color: #6b5d49; font-size: 13px; }
.preload-hint { margin-top: 12px; font-size: 12px; color: var(--primary-dark); background: var(--primary-soft); border-radius: 9px; padding: 8px 12px; }
/* 后台准备进度条（右下、不挡操作） */
.preload-bar {
  position: fixed; right: 24px; bottom: 96px; z-index: 90;
  background: rgba(61,54,46,.92); color: #f5eee2; font-size: 12px;
  padding: 9px 16px; border-radius: 99px; box-shadow: 0 8px 24px rgba(61,54,46,.25);
  animation: fadeIn .25s ease;
}
.preload-bar span { color: #e3c98f; margin-left: 6px; }

/* ===== 右下角圆形「回到顶部」：固定在视口，所有页面始终可用 ===== */
.back-top {
  position: fixed; right: 26px; bottom: 28px; z-index: 80;
  width: 58px; height: 58px; border-radius: 50%;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  border: 1px solid rgba(255,253,248,.55);
  background: linear-gradient(135deg, #b07a52, #8a5a38); color: #fffdf8;
  box-shadow: 0 6px 20px rgba(120,80,50,.28), 0 2px 5px rgba(120,80,50,.18);
  cursor: pointer; opacity: .72;
  transition: transform .2s ease, box-shadow .2s ease, opacity .2s ease;
}
.back-top:hover, .back-top:focus-visible {
  transform: translateY(-3px); opacity: 1; outline: none;
  box-shadow: 0 10px 26px rgba(120,80,50,.36);
}
.back-top.scrolled { opacity: 1; }
.back-top svg { width: 19px; height: 19px; fill: none; stroke: currentColor; stroke-width: 2.2; stroke-linecap: round; stroke-linejoin: round; }
.back-top span { font-size: 9px; letter-spacing: .12em; line-height: 1.15; margin-top: 1px; }

/* ===== 读一读：全文统计 + 逐段统计 ===== */
.stats-card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow); padding: 14px 18px 16px; margin-bottom: 16px;
  border-top: 2px solid rgba(201,162,39,.6);
}
.stats-title {
  display: flex; align-items: baseline; gap: 10px; flex-wrap: wrap;
  font-family: var(--serif); font-size: 14px; font-weight: 700; color: var(--primary-dark); margin-bottom: 10px;
}
.stats-note { font-family: inherit; font-size: 11px; font-weight: 400; color: var(--muted); }
.stats-grid { display: grid; grid-template-columns: repeat(6, minmax(0,1fr)); gap: 8px; }
.stat-item {
  background: #fbf6ec; border: 1px solid #efe3cf; border-radius: 10px;
  padding: 7px 4px; text-align: center; min-width: 0;
}
.stat-item b { display: block; font-family: Georgia, serif; font-size: 19px; color: var(--primary-dark); line-height: 1.25; }
.stat-item span { display: block; font-size: 11px; color: var(--muted); white-space: nowrap; }
.stat-item.key { background: var(--primary-soft); border-color: #e7d3b8; }
.para-stats {
  display: flex; flex-wrap: wrap; align-items: center; gap: 6px 12px;
  margin-top: 12px; padding-top: 10px; border-top: 1px dashed var(--line);
  font-size: 11.5px; color: var(--muted);
}
.para-stats .ps-label { color: var(--primary-dark); font-weight: 600; }
.para-stats b { color: var(--ink); font-family: Georgia, serif; font-size: 13px; margin-left: 2px; }

/* ===== v23 · 第三页：播放起点 ===== */
.play-start-bar {
  display: flex; align-items: center; flex-wrap: wrap; gap: 8px 12px;
  margin: 12px 0 4px; padding: 9px 14px;
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: 0 1px 2px rgba(90,70,50,.05);
}
.psb-icon { font-size: 15px; line-height: 1; }
.psb-label {
  font-family: var(--serif); font-size: 14px; font-weight: 700; color: var(--primary-dark);
  background: var(--primary-soft); border: 1px solid #e7d3b8; border-radius: 99px; padding: 2px 12px;
}
.psb-tip { flex: 1 1 260px; line-height: 1.6; }
.play-start-bar .btn.chip { padding: 4px 12px; font-size: 12px; white-space: nowrap; }
.v-title-row { display: flex; align-items: baseline; flex-wrap: wrap; gap: 0 6px; }
.v-start-badge {
  display: inline-block; font-size: 11px; font-weight: 700; letter-spacing: .04em;
  color: #4f7350; background: #eef3e9; border: 1px solid #cddcc6;
  border-radius: 99px; padding: 1px 9px; margin-left: 4px; white-space: nowrap;
}
.vocab-item.start-point { border-color: #9db79a; box-shadow: 0 0 0 2px rgba(139,160,133,.30); }
/* 播放中的金色高亮优先级最高，起点仍用左侧绿色标识保留可见 */
.vocab-item.start-point.current {
  border-color: var(--accent); box-shadow: 0 0 0 2px var(--accent), 0 6px 18px rgba(201,162,39,.18);
  border-left: 4px solid #8ba085;
}
.v-btns .btn { white-space: nowrap; }
.v-btns .btn.start-set.active { background: #eef3e9; color: #4f7350; border-color: #cddcc6; cursor: default; }
.v-btns .btn.start-play { color: var(--primary-dark); border-color: #e0c9a8; }

/* ===== v23 · 第四页：逐句卡片 + 结构可视化 ===== */
.grammar-overview {
  display: flex; flex-wrap: wrap; align-items: baseline; gap: 6px 14px;
  background: var(--card); border: 1px solid var(--line); border-left: 3px solid rgba(201,162,39,.7);
  border-radius: var(--radius); padding: 12px 18px; margin-bottom: 14px; font-size: 13px;
}
.grammar-overview b { font-family: Georgia, serif; font-size: 16px; color: var(--primary-dark); }
.go-title { font-family: var(--serif); font-size: 15px; font-weight: 700; color: var(--primary-dark); }
.grammar-overview .muted { flex: 1 1 100%; line-height: 1.6; }
.g-sentence {
  background: #fffdf8; border: 1px solid var(--line); border-radius: 12px;
  padding: 14px 16px; margin: 12px 0; box-shadow: 0 1px 2px rgba(90,70,50,.04);
}
.g-sentence:first-of-type { margin-top: 4px; }
.gs-head { display: flex; align-items: center; flex-wrap: wrap; gap: 8px; margin-bottom: 8px; }
.gs-no {
  font-family: Georgia, serif; font-size: 12px; font-weight: 700; color: var(--accent);
  background: #faf4e8; border-radius: 99px; padding: 1px 10px;
}
.tense-tag {
  font-size: 12px; font-weight: 700; color: #4f7350; background: #eef3e9;
  border: 1px solid #cddcc6; border-radius: 99px; padding: 2px 12px; white-space: nowrap;
}
.gs-text {
  font-family: Georgia, "Times New Roman", serif; font-size: 15px; line-height: 1.8;
  color: #35302a; background: var(--primary-soft); border-radius: 9px; padding: 8px 12px;
}
.gs-tr { margin-top: 6px; font-size: 13px; color: #6b5d49; line-height: 1.7; }
.gs-label {
  font-size: 12px; font-weight: 700; color: var(--primary-dark);
  margin: 14px 0 6px; padding-left: 9px; border-left: 3px solid rgba(169,113,75,.55);
}
.gs-empty { font-size: 12.5px; color: var(--muted); padding: 6px 2px; }
.g-sentence .g-point { border-top: 1px dashed #e2d5bd; padding: 10px 0; }
.g-sentence .g-point:first-of-type { border-top: none; }
.parts-list { display: flex; flex-direction: column; gap: 7px; }
.part-row {
  display: flex; align-items: baseline; flex-wrap: wrap; gap: 5px 10px;
  background: #fbf6ec; border: 1px solid var(--line); border-radius: 10px; padding: 8px 11px;
  font-size: 12.5px; line-height: 1.6;
}
.part-row.is-main { background: var(--primary-soft); border-color: #e7d3b8; }
.part-id {
  flex: none; display: inline-flex; align-items: center; justify-content: center;
  min-width: 20px; height: 20px; border-radius: 6px; background: #fffdf8;
  border: 1px solid var(--line); font-weight: 700; color: var(--primary-dark); font-size: 11px;
}
.part-kind { flex: none; font-weight: 700; color: #5f7a58; }
.part-row.is-main .part-kind { color: var(--primary-dark); }
.part-text { flex: 1 1 240px; min-width: 0; font-family: Georgia, serif; color: #35302a; word-break: break-word; }
.part-arrow { flex: none; color: var(--primary-dark); font-size: 11.5px; white-space: nowrap; }
.part-rel { flex: none; color: var(--sage); font-size: 11px; }
.part-tag { flex: none; font-size: 11px; color: #fff; background: var(--primary); border-radius: 99px; padding: 1px 9px; }
.struct-viz { margin-top: 14px; }
.struct-title { font-size: 13px; font-weight: 700; color: var(--primary-dark); margin-bottom: 7px; }
.struct-title .muted { font-weight: 400; margin-left: 8px; }
.struct-scroll {
  overflow-x: auto; -webkit-overflow-scrolling: touch;
  background: #fffdf8; border: 1px solid var(--line); border-radius: 10px;
}
.struct-scroll svg { display: block; }

/* 响应式 */
@media (max-width: 640px) {
  .play-start-bar { padding: 8px 10px; gap: 6px 8px; }
  .psb-tip { flex-basis: 100%; }
  .part-text { flex-basis: 100%; }
  .grammar-overview { padding: 10px 12px; }
  .g-sentence { padding: 12px 10px; }
  .struct-scroll svg { min-width: 620px; }
  .topbar { padding: 8px 12px; }
  .logo { font-size: 16px; } .logo-sub, .logo-en { display: none; }
  main { padding: 12px 10px 70px; }
  .study-tabs { top: 64px; gap: 4px; padding: 7px; }
  /* 4 个标签在窄屏排两行，避免「单词领读与记忆」与「语法讲解」文字互相挤压 */
  .tab { flex: 1 1 44%; min-width: 0; font-size: 12px; padding: 8px 3px; }
  .para-text, .mode-original { font-size: 16px; }
  .tok .t-w { font-size: 15px; }
  .sentence-pair { grid-template-columns: 24px 1fr; }
  #tooltip { max-width: 88vw; }
  .ai-badge { display: none; }
  .back-top { right: 14px; bottom: 18px; width: 50px; height: 50px; }
  .preload-bar { right: 12px; bottom: 76px; font-size: 11px; padding: 8px 12px; }
  .lib-actions { width: 100%; }
  .stats-grid { grid-template-columns: repeat(3, minmax(0,1fr)); }
  .stat-item b { font-size: 16px; }
}