/* ============ 基础 ============ */
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
:root{
  --bg:#f4f7fb;
  --card:#ffffff;
  --ink:#16213a;
  --ink-2:#3d4a63;
  --muted:#7b8699;
  --line:#e5eaf2;
  --line-2:#eef2f8;
  --accent:#0f9d76;
  --accent-soft:#e9f8f2;
  --accent-2:#c9efe2;
  --shadow:0 1px 2px rgba(22,33,58,.05),0 8px 24px -12px rgba(22,33,58,.18);
  --radius:16px;
}
body[data-subject="phys"]{
  --accent:#2b6ef2;
  --accent-soft:#eaf1ff;
  --accent-2:#cfe0ff;
}
body[data-subject="math"]{
  --accent:#c2410c;
  --accent-soft:#fdeee6;
  --accent-2:#f8d6c4;
}
html,body{margin:0;padding:0}
body{
  background:var(--bg);
  color:var(--ink);
  font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC",sans-serif;
  font-size:15px;
  line-height:1.65;
  -webkit-font-smoothing:antialiased;
  padding-bottom:40px;
}
h1,h2,h3,h4{margin:0;font-weight:700;letter-spacing:.2px}
p{margin:0}
button{font-family:inherit;cursor:pointer;border:none;background:none;color:inherit}
.hidden{display:none !important}

/* ============ 顶栏 ============ */
.topbar{
  position:sticky;top:0;z-index:30;
  display:flex;align-items:center;gap:14px;
  padding:10px 18px;
  background:rgba(255,255,255,.86);
  backdrop-filter:saturate(180%) blur(14px);
  -webkit-backdrop-filter:saturate(180%) blur(14px);
  border-bottom:1px solid var(--line);
}
.brand{display:flex;align-items:center;gap:10px;min-width:0}
.logo{
  width:38px;height:38px;flex:0 0 38px;border-radius:11px;
  background:linear-gradient(135deg,var(--accent),color-mix(in srgb,var(--accent) 60%,#7bd3ff));
  color:#fff;display:flex;align-items:center;justify-content:center;
  font-weight:800;font-size:19px;box-shadow:0 4px 12px -4px var(--accent);
}
.brand-txt{min-width:0}
.brand-txt h1{font-size:16px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.brand-txt p{font-size:11.5px;color:var(--muted);margin-top:1px;white-space:nowrap}

.subject-switch{
  display:flex;background:var(--line-2);border-radius:11px;padding:3px;flex:0 0 auto;
}
.subject-switch button{
  padding:6px 15px;border-radius:9px;font-size:13.5px;font-weight:600;color:var(--muted);
  transition:.18s;
}
.subject-switch button.on{
  background:#fff;color:var(--accent);box-shadow:0 1px 4px rgba(22,33,58,.12);
}

.top-actions{margin-left:auto;display:flex;align-items:center;gap:8px}
.search-wrap{position:relative}
.search-wrap input{
  width:230px;padding:8px 30px 8px 12px;border-radius:10px;
  border:1px solid var(--line);background:#fbfcfe;font-size:13.5px;color:var(--ink);
  outline:none;transition:.18s;font-family:inherit;
}
.search-wrap input:focus{border-color:var(--accent);background:#fff;box-shadow:0 0 0 3px var(--accent-soft)}
.search-wrap input::-webkit-search-cancel-button,
.search-wrap input::-webkit-search-decoration{-webkit-appearance:none;display:none}
.search-clear{
  position:absolute;right:4px;top:50%;transform:translateY(-50%);
  width:22px;height:22px;border-radius:50%;color:var(--muted);font-size:15px;
  display:none;align-items:center;justify-content:center;
}
.search-wrap.has-value .search-clear{display:flex}
.icon-btn{
  padding:8px 13px;border-radius:10px;background:var(--accent-soft);color:var(--accent);
  font-size:13px;font-weight:600;white-space:nowrap;
}

/* 使用者切换 */
.user-chip{
  display:flex;align-items:center;gap:6px;padding:5px 10px 5px 5px;
  border:1px solid var(--line);border-radius:20px;background:#fff;
  font-size:12.5px;font-weight:600;color:var(--ink-2);white-space:nowrap;
  transition:.15s;
}
.user-chip:hover{border-color:var(--accent-2);background:var(--accent-soft)}
.uc-avatar{
  flex:0 0 auto;width:22px;height:22px;border-radius:50%;
  background:var(--accent);color:#fff;font-size:11.5px;font-weight:700;
  display:flex;align-items:center;justify-content:center;
}
.uc-name{max-width:76px;overflow:hidden;text-overflow:ellipsis}
.uc-save{font-size:10.5px;color:var(--muted);font-weight:500}

.user-modal{max-width:440px}
.user-list{display:flex;flex-direction:column;gap:7px;margin:12px 0;max-height:42vh;overflow:auto}
.user-row{
  display:flex;align-items:center;gap:9px;padding:10px 12px;text-align:left;
  border:1px solid var(--line);border-radius:10px;background:#fff;transition:.15s;
  cursor:pointer;
}
.user-row:hover{border-color:var(--accent-2)}
.user-row.on{border-color:var(--accent);background:var(--accent-soft)}
.udel{
  flex:0 0 auto;width:22px;height:22px;border-radius:6px;border:none;background:transparent;
  color:#cbd5e1;font-size:16px;line-height:1;font-family:inherit;cursor:pointer;
  display:flex;align-items:center;justify-content:center;transition:.15s;
}
.udel:hover{background:#fee2e2;color:#dc2626}
.ua{
  flex:0 0 auto;width:26px;height:26px;border-radius:50%;background:var(--accent);
  color:#fff;font-size:12px;font-weight:700;display:flex;align-items:center;justify-content:center;
}
.un{flex:1;min-width:0;font-size:14px;font-weight:600;color:var(--ink);
  overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.ul{font-size:12px;flex:0 0 auto}
.uc{font-size:11px;color:var(--accent);font-weight:700;flex:0 0 auto}
.user-empty{font-size:13px;color:var(--muted);padding:10px 0;text-align:center}
.user-new{display:flex;gap:7px;margin-top:4px}
.user-new input{
  flex:1;min-width:0;padding:9px 11px;border:1px solid var(--line);border-radius:9px;
  font-size:13.5px;font-family:inherit;color:var(--ink);outline:none;
}
.user-new input:focus{border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-soft)}
.user-new .btn-primary{flex:0 0 auto;padding:9px 16px;font-size:13px}
.modal .user-new .btn-primary{width:auto}
.user-err{font-size:12px;color:#dc2626;margin-top:8px;min-height:17px}
.user-close{margin-top:8px;width:100%;padding:9px}


/* ============ 标签栏 ============ */
.tabs{
  display:flex;gap:6px;padding:10px 18px 0;
  max-width:1180px;margin:0 auto;
  overflow-x:auto;scrollbar-width:none;-ms-overflow-style:none;
}
.tabs::-webkit-scrollbar{display:none}
.tabs button{
  padding:8px 16px;border-radius:10px;font-size:14px;font-weight:600;color:var(--muted);
  transition:.16s;white-space:nowrap;flex:0 0 auto;
}
.tabs button.on{background:#fff;color:var(--accent);box-shadow:var(--shadow)}
.tabs button:hover{color:var(--ink-2)}

main{max-width:1180px;margin:0 auto;padding:14px 18px 30px}

/* ============ 图谱 ============ */
.graph-card{
  background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);
  border:1px solid var(--line);overflow:hidden;position:relative;
}
.graph-head{
  display:flex;align-items:flex-start;gap:12px;padding:16px 18px 8px;flex-wrap:wrap;
}
.graph-head h2{font-size:17px}
.graph-head p{font-size:12.5px;color:var(--muted);margin-top:3px}
.graph-hint{
  margin-left:auto;display:flex;align-items:center;gap:4px;white-space:nowrap;
}
.hint-txt{font-size:12px;color:var(--muted);margin-right:6px}
.graph-hint button{
  width:28px;height:28px;border-radius:8px;border:1px solid var(--line);background:#fff;
  color:var(--ink-2);font-size:14px;font-weight:600;display:flex;align-items:center;justify-content:center;
  box-shadow:0 1px 3px rgba(22,33,58,.06);
}
.graph-hint button:active{transform:scale(.94)}
.graph-body{display:flex;align-items:stretch;border-top:1px solid var(--line-2)}
.graph-stage{
  position:relative;flex:0 0 520px;width:520px;max-width:520px;
  background:radial-gradient(circle at 50% 45%,#fbfdff 0%,#f7fafd 55%,#f3f7fc 100%);
  border-right:1px solid var(--line-2);
}
.graph-stage svg{display:block;width:100%;height:auto;touch-action:pan-y;cursor:grab}
.graph-side{
  flex:1;min-width:0;padding:16px 20px 18px;display:flex;flex-direction:column;gap:14px;
}
.side-title{font-size:11.5px;font-weight:700;color:var(--muted);letter-spacing:.8px}
.side-list{display:grid;grid-template-columns:1fr 1fr;gap:7px}
.side-item{
  display:flex;align-items:center;gap:7px;padding:8px 10px;border-radius:9px;
  border:1px solid var(--line);background:#fff;font-size:12.5px;font-weight:600;
  color:var(--ink-2);text-align:left;line-height:1.3;
}
.side-item:hover{border-color:var(--accent-2);background:var(--accent-soft)}
.side-item.on{background:var(--accent);border-color:var(--accent);color:#fff}
.si-no{
  flex:0 0 auto;width:19px;height:19px;border-radius:6px;background:var(--line-2);
  color:var(--muted);font-size:10.5px;font-weight:700;display:flex;align-items:center;justify-content:center;
}
.side-item.on .si-no{background:rgba(255,255,255,.22);color:#fff}
.si-tick{margin-left:auto;color:var(--accent);font-size:11px}
.side-item.on .si-tick{color:#fff}
.graph-stage svg.dragging{cursor:grabbing}

/* 图谱 SVG 元素 */
.edge{stroke:#d7e2ef;stroke-width:1.4;fill:none}
.edge-sub{stroke:var(--accent);stroke-width:1.2;stroke-dasharray:4 4;opacity:.55;fill:none}
.node{cursor:pointer}
.node circle{transition:.2s}
.node.chap circle{fill:#fff;stroke:var(--accent);stroke-width:2.2}
.node.chap:hover circle{fill:var(--accent-soft)}
.node.chap.active circle{fill:var(--accent);stroke:var(--accent)}
.node.chap.active .lbl-no{fill:#fff}
.node.dim{opacity:.3}
.node.chap.dim .lbl-chap{display:none}
.lbl-no{font-size:21px;font-weight:700;fill:var(--accent);text-anchor:middle;pointer-events:none}
.lbl-chap{font-size:23px;font-weight:600;fill:var(--ink-2);text-anchor:middle;pointer-events:none}
.node.chap.active .lbl-chap{fill:var(--accent);font-weight:700}
.node.center circle{fill:var(--accent);stroke:none}
.lbl-center{font-size:31px;font-weight:800;fill:#fff;text-anchor:middle;pointer-events:none}
.lbl-center-sub{font-size:14px;fill:rgba(255,255,255,.8);text-anchor:middle;pointer-events:none}
.node.sub circle{fill:var(--accent-2);stroke:var(--accent);stroke-width:1.5}
.lbl-sub{font-size:18px;fill:var(--ink-2);pointer-events:none}
.lbl-focus{font-size:27px;font-weight:800;fill:var(--ink);text-anchor:middle;pointer-events:none}
.gd-top{display:flex;align-items:center;gap:8px;margin-bottom:6px}
.gd-tag{font-size:11.5px;font-weight:700;color:var(--accent);background:var(--accent-soft);padding:2px 8px;border-radius:20px}
.link-btn{margin-left:auto;font-size:12px;font-weight:600;color:var(--muted);text-decoration:underline;text-underline-offset:3px}
.link-btn:hover{color:var(--accent)}

.graph-detail{
  background:#fbfcfe;border:1px solid var(--line-2);border-radius:12px;padding:14px 15px;
}
.graph-detail h3{font-size:15.5px;line-height:1.45}
.graph-detail p{font-size:12.5px;color:var(--muted);margin-top:5px;line-height:1.7}
.graph-detail .btn-primary{margin-top:12px;width:100%}
.btn-primary{
  padding:9px 18px;border-radius:10px;background:var(--accent);color:#fff;
  font-size:13.5px;font-weight:600;box-shadow:0 6px 16px -8px var(--accent);
}
.btn-primary:active{transform:translateY(1px)}
.legend{display:flex;gap:14px;flex-wrap:wrap}
.legend span{display:flex;align-items:center;gap:6px;font-size:12px;color:var(--muted)}
.dot{width:10px;height:10px;border-radius:50%}
.dot.c1{background:var(--accent)}
.dot.c2{background:#fff;border:2px solid var(--accent)}
.dot.c3{background:var(--accent-2);border:1px solid var(--accent)}

/* ============ 章节选择条 ============ */
.chip-bar{
  display:flex;gap:8px;overflow-x:auto;padding:2px 2px 12px;
  scrollbar-width:none;-ms-overflow-style:none;
}
.chip-bar::-webkit-scrollbar{display:none}
.chip{
  flex:0 0 auto;padding:8px 14px;border-radius:10px;background:#fff;border:1px solid var(--line);
  font-size:13px;font-weight:600;color:var(--ink-2);white-space:nowrap;transition:.16s;
  display:flex;align-items:center;gap:6px;
}
.chip.on{background:var(--accent);border-color:var(--accent);color:#fff;box-shadow:0 6px 14px -8px var(--accent)}
.chip .tick{font-size:11px;opacity:.9}
.chip.on .tick{color:#fff}

/* ============ 章节内容 ============ */
.chap-hero{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:20px;box-shadow:var(--shadow);position:relative;overflow:hidden;
}
.chap-hero::after{
  content:"";position:absolute;right:-60px;top:-70px;width:170px;height:170px;border-radius:50%;
  background:var(--accent-soft);opacity:.55;
}
.chap-hero .no{
  display:inline-block;font-size:12px;font-weight:700;color:var(--accent);
  background:var(--accent-soft);padding:3px 10px;border-radius:20px;margin-bottom:8px;
}
.chap-hero h2{font-size:22px;line-height:1.35}
.chap-hero .summary{font-size:13.5px;color:var(--muted);margin-top:8px;max-width:640px;position:relative}
.hero-actions{display:flex;gap:10px;margin-top:14px;position:relative;flex-wrap:wrap}

/* 章节图标 + 生活场景 */
.hero-main{display:flex;gap:14px;align-items:flex-start;position:relative}
.hero-icon{
  flex:0 0 auto;width:58px;height:58px;border-radius:18px;
  display:flex;align-items:center;justify-content:center;
  font-size:30px;line-height:1;
  font-family:"Apple Color Emoji","Segoe UI Emoji","Noto Color Emoji",sans-serif;
  background:radial-gradient(circle at 32% 26%,#fff 0%,var(--accent-soft) 58%,var(--accent-2) 100%);
  border:1px solid var(--accent-2);
  box-shadow:0 8px 18px -10px var(--accent),inset 0 0 0 3px rgba(255,255,255,.85);
  animation:iconFloat 4s ease-in-out infinite;
}
@keyframes iconFloat{
  0%,100%{transform:translateY(0) rotate(-2deg)}
  50%{transform:translateY(-4px) rotate(2deg)}
}
.hero-txt{min-width:0;flex:1}

.life-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:10px}
.life-card{
  display:flex;gap:9px;align-items:flex-start;
  padding:12px 15px;border-radius:14px;
  background:linear-gradient(135deg,#fffdf6,#fff);
  border:1px solid #f0e6cd;
  transition:transform .18s ease,box-shadow .18s ease;
}
.life-card .lc-ico{
  flex:0 0 auto;font-size:15px;line-height:1.6;
  font-family:"Apple Color Emoji","Segoe UI Emoji","Noto Color Emoji",sans-serif;
}
.life-card p{margin:0;font-size:13.5px;line-height:1.75;color:var(--ink-2)}
.life-card:hover{transform:translateY(-2px);box-shadow:0 6px 16px rgba(180,140,40,.13)}

.btn-ghost{
  padding:8px 14px;border-radius:10px;border:1px solid var(--line);background:#fff;
  font-size:13px;font-weight:600;color:var(--ink-2);
}
.btn-ghost.on{background:var(--accent-soft);border-color:var(--accent-2);color:var(--accent)}

.block{margin-top:20px}
.block-title{
  display:flex;align-items:center;gap:9px;margin-bottom:12px;
}
.block-title .idx{
  width:24px;height:24px;border-radius:8px;background:var(--accent);color:#fff;
  font-size:12.5px;font-weight:700;display:flex;align-items:center;justify-content:center;
}
.block-title h3{font-size:16px}
.block-title .cnt{font-size:12px;color:var(--muted);margin-left:2px}

.point-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:10px}
.point{
  background:#fff;border:1px solid var(--line);border-radius:12px;padding:13px 15px;
  box-shadow:0 1px 2px rgba(22,33,58,.03);
}
.point h4{font-size:14px;color:var(--accent);margin-bottom:4px;display:flex;gap:6px;align-items:baseline}
.point h4 .n{font-size:11px;color:var(--muted);font-weight:600}
.point p{font-size:13px;color:var(--ink-2);line-height:1.72}

.type-card{
  background:#fff;border:1px solid var(--line);border-radius:14px;padding:16px 18px;
  margin-bottom:12px;box-shadow:0 1px 2px rgba(22,33,58,.03);
}
.type-head{display:flex;align-items:center;gap:9px;margin-bottom:8px}
.badge{
  font-size:11.5px;font-weight:700;color:var(--accent);background:var(--accent-soft);
  padding:2px 9px;border-radius:6px;white-space:nowrap;
}
.type-head h4{font-size:15px}
.method{
  font-size:13px;color:var(--ink-2);background:#f8fafd;border-left:3px solid var(--accent-2);
  padding:9px 12px;border-radius:0 8px 8px 0;line-height:1.72;
}
.method b{color:var(--accent);font-weight:700}
.example{margin-top:11px;border:1px dashed var(--line);border-radius:10px;padding:12px 13px;background:#fcfdff}
.ex-q{font-size:13.5px;color:var(--ink);white-space:pre-line;line-height:1.8}
.ex-q b{color:var(--accent);font-weight:700;margin-right:4px}
.ex-a{
  margin-top:10px;padding-top:10px;border-top:1px dashed var(--line);
  font-size:13px;color:var(--ink-2);line-height:1.78;
}
.ex-a .ans{color:#c2410c;font-weight:700}
.ex-a ol{margin:6px 0 0;padding-left:20px}
.ex-a li{margin-bottom:4px}
.ex-a li::marker{color:var(--accent);font-weight:700}
.toggle{
  display:inline-flex;align-items:center;gap:5px;margin-top:9px;
  padding:5px 12px;border-radius:8px;background:var(--accent-soft);color:var(--accent);
  font-size:12.5px;font-weight:600;
}
.toggle:active{transform:scale(.97)}

/* ============ 训练题 ============ */
.quiz-bar{display:flex;align-items:center;gap:10px;margin-bottom:12px;flex-wrap:wrap}
.quiz-bar .tip{font-size:12px;color:var(--muted)}
.q-card{
  background:#fff;border:1px solid var(--line);border-radius:12px;padding:14px 16px;
  margin-bottom:10px;display:flex;gap:12px;box-shadow:0 1px 2px rgba(22,33,58,.03);
}
.q-no{
  flex:0 0 26px;width:26px;height:26px;border-radius:8px;background:var(--line-2);
  color:var(--ink-2);font-size:12.5px;font-weight:700;display:flex;align-items:center;justify-content:center;
  margin-top:1px;
}
.q-body{flex:1;min-width:0}
.q-text{font-size:13.5px;white-space:pre-line;line-height:1.8}
.q-ans{
  margin-top:10px;padding:10px 12px;border-radius:9px;background:#f7fbf9;
  border:1px solid var(--accent-2);font-size:13px;line-height:1.78;color:var(--ink-2);
}
body[data-subject="phys"] .q-ans{background:#f7faff;border-color:var(--accent-2)}
.q-ans .lab{
  display:inline-block;font-size:11px;font-weight:700;color:#fff;background:var(--accent);
  padding:1px 7px;border-radius:5px;margin-right:6px;vertical-align:1px;
}
.q-ans .lab.exp{background:#94a3b8}
.q-ans .ans-txt{font-weight:600;color:#0b7a5c}
body[data-subject="phys"] .q-ans .ans-txt{color:#1d4ed8}

.pager{display:flex;gap:10px;justify-content:space-between;margin-top:22px}
.pager button{
  flex:1;padding:11px;border-radius:11px;background:#fff;border:1px solid var(--line);
  font-size:13.5px;font-weight:600;color:var(--ink-2);
}
.pager button:disabled{opacity:.4;cursor:not-allowed}

/* ============ 进度 ============ */
.prog-hero{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:20px;box-shadow:var(--shadow);
}
.prog-hero h2{font-size:18px}
.prog-hero p{font-size:13px;color:var(--muted);margin-top:4px}
.bar{
  height:10px;border-radius:10px;background:var(--line-2);margin-top:14px;overflow:hidden;
}
.bar i{display:block;height:100%;border-radius:10px;background:linear-gradient(90deg,var(--accent),color-mix(in srgb,var(--accent) 55%,#7bd3ff));transition:width .4s}
.prog-stats{display:flex;gap:22px;margin-top:12px;flex-wrap:wrap}
.prog-stats div{font-size:12.5px;color:var(--muted)}
.prog-stats b{display:block;font-size:20px;color:var(--ink);font-weight:800}
.prog-list{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:10px;margin-top:16px}
.prog-item{
  display:flex;align-items:center;gap:10px;padding:12px 14px;background:#fff;
  border:1px solid var(--line);border-radius:12px;
}
.prog-item .pi-no{font-size:11.5px;color:var(--muted);font-weight:700;flex:0 0 auto}
.prog-item .pi-title{font-size:13.5px;font-weight:600;flex:1;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.check{
  width:22px;height:22px;flex:0 0 22px;border-radius:7px;border:1.6px solid var(--line);
  display:flex;align-items:center;justify-content:center;font-size:13px;color:transparent;background:#fff;
}
.check.on{background:var(--accent);border-color:var(--accent);color:#fff}
.prog-item.done{background:var(--accent-soft);border-color:var(--accent-2)}

/* ============ 搜索结果 ============ */
.search-head{font-size:13px;color:var(--muted);margin-bottom:10px}
.sr-card{
  background:#fff;border:1px solid var(--line);border-radius:12px;padding:14px 16px;margin-bottom:10px;
}
.sr-card h4{font-size:14.5px;color:var(--accent);margin-bottom:4px}
.sr-card .sr-sub{font-size:12px;color:var(--muted);margin-bottom:6px}
.sr-card .sr-snip{font-size:13px;color:var(--ink-2);line-height:1.7}
.sr-card mark{background:#fff3c4;color:inherit;padding:0 1px;border-radius:2px}
.empty{
  text-align:center;padding:60px 20px;color:var(--muted);font-size:14px;
}

/* ============ 弹窗 ============ */
.modal-mask{
  position:fixed;inset:0;background:rgba(16,24,40,.45);z-index:100;
  display:flex;align-items:center;justify-content:center;padding:20px;
  backdrop-filter:blur(3px);
}
.modal{
  background:#fff;border-radius:18px;padding:22px;max-width:420px;width:100%;
  box-shadow:0 24px 60px -20px rgba(16,24,40,.4);
}
.modal h3{font-size:17px;margin-bottom:8px}
.modal p{font-size:13px;color:var(--ink-2);line-height:1.7}
.url-box{
  margin:12px 0;padding:12px;border-radius:10px;background:#0f172a;color:#7bd3ff;
  font-family:ui-monospace,SFMono-Regular,Consolas,monospace;font-size:14px;
  text-align:center;word-break:break-all;letter-spacing:.3px;
}
.modal-tip{font-size:12px !important;color:var(--muted) !important}
.modal-steps{margin:10px 0 16px;padding-left:20px;font-size:12.5px;color:var(--muted);line-height:1.8}
.modal .btn-primary{width:100%;padding:11px}

/* 手机查看：域名 + 二维码 */
.qr-modal{text-align:center}
.qr-wrap{
  margin:14px auto 18px;padding:12px;width:204px;height:204px;
  border-radius:14px;background:#fff;border:1px solid #e2e8f0;
  box-shadow:0 2px 10px rgba(15,23,42,.06);display:flex;align-items:center;justify-content:center;
}
.qr-wrap img{width:180px;height:180px;display:block;image-rendering:pixelated}
.qr-modal .url-box{margin:10px 0 0}

/* ============ 响应式 ============ */
@media (max-width:820px){
  .topbar{flex-wrap:wrap;gap:8px;padding:8px 12px}
  .brand{order:1}
  .brand-txt h1{font-size:14.5px}
  .brand-txt p{font-size:11px}
  .subject-switch{order:2;margin-left:auto}
  .top-actions{order:3;width:100%;margin-left:0}
  .search-wrap{flex:1}
  .search-wrap input{width:100%;font-size:13.5px}
  .icon-btn{padding:8px 12px;font-size:12.5px}
  .lbl-chap{font-size:26px}
  .lbl-no{font-size:24px}
  .lbl-sub{font-size:20px}
  .lbl-focus{font-size:30px}
  .lbl-center{font-size:34px}
  .lbl-center-sub{font-size:15px}
  .tabs{padding:8px 12px 0;gap:4px}
  .tabs button{padding:7px 11px;font-size:12.5px}
  main{padding:12px 12px 30px}
  .graph-head{padding:12px 14px 10px;flex-wrap:nowrap;align-items:center;gap:8px}
  .graph-head>div:first-child{flex:1;min-width:0}
  .graph-head h2{font-size:15.5px}
  .graph-head p{white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
  .hint-txt{display:none}
  .graph-hint{margin-left:auto}
  .graph-body{flex-direction:column}
  .graph-stage{flex:none;width:100%;max-width:100%;border-right:none;border-bottom:1px solid var(--line-2)}
  .graph-side{padding:12px 14px 16px;gap:12px}
  .graph-detail{padding:13px 14px}
  .legend{gap:12px}
  .side-list{grid-template-columns:1fr 1fr;gap:6px}
  .side-item{font-size:12px;padding:7px 8px}
  .chap-hero{padding:16px}
  .chap-hero h2{font-size:19px}
  .hero-main{gap:11px}
  .hero-icon{width:46px;height:46px;font-size:23px;border-radius:13px}
  .life-grid{grid-template-columns:1fr}
  .life-card{font-size:13px;padding:11px 13px}
  .point-grid{grid-template-columns:1fr}
  .type-card{padding:14px}
  .q-card{padding:12px;gap:9px}
  .prog-list{grid-template-columns:1fr}
  .pager button{font-size:13px;padding:10px 6px}
}
@media (max-width:420px){
  .brand-txt h1{font-size:13.5px}
}

/* 尊重系统"减少动态效果"设置 */
@media (prefers-reduced-motion:reduce){
  .hero-icon{animation:none}
  *{animation-duration:.001ms !important;animation-iteration-count:1 !important;transition-duration:.001ms !important}
}

/* 打印 */
@media print{
  .topbar,.tabs,.chip-bar,.pager,.zoom-bar,.toggle{display:none !important}
  body{background:#fff}
  .q-ans,.ex-a{display:block !important}
  .hero-icon{animation:none;box-shadow:none}
  .life-card{break-inside:avoid}
}

/* ============================================================
   多版本教材（学科 × 出版社）扩展样式
   ============================================================ */

/* 学科按钮里的图标 */
.subject-switch button i{font-style:normal;margin-right:5px;font-size:14px}

/* ---- 第二步：出版社选择条 ---- */
.edition-bar{
  display:flex;align-items:center;gap:8px;flex-wrap:wrap;
  padding:9px 22px;background:var(--card);border-bottom:1px solid var(--line);
}
.eb-label{
  font-size:11.5px;font-weight:800;color:var(--muted);
  letter-spacing:.6px;flex:0 0 auto;
}
.eb-chip{
  padding:5px 14px;border-radius:9px;font-size:13px;font-weight:600;
  color:var(--muted);border:1px solid var(--line);background:#fff;transition:.16s;
}
.eb-chip:hover{border-color:var(--accent-2);color:var(--accent)}
.eb-chip.on{
  background:var(--accent);border-color:var(--accent);color:#fff;
  box-shadow:0 6px 14px -8px var(--accent);
}
.eb-meta{margin-left:auto;font-size:11.5px;color:var(--muted);flex:1 1 auto;text-align:right}

/* ---- 章节切换：按单元分组 ---- */
.chip-bar{flex-direction:column;gap:9px;overflow:visible;padding-bottom:14px}
.chip-unit{display:flex;align-items:flex-start;gap:9px;width:100%}
.chip-unit-n{
  flex:0 0 auto;font-size:11px;font-weight:800;color:var(--muted);
  background:var(--line-2);border-radius:7px;padding:4px 9px;margin-top:2px;
  letter-spacing:.5px;white-space:nowrap;
}
.chip-unit-list{display:flex;flex-wrap:wrap;gap:6px;flex:1 1 auto;min-width:0}

/* ---- 知识要点：按课题分组 ---- */
.sec-group{margin-bottom:14px}
.sec-head{display:flex;align-items:center;gap:8px;margin-bottom:8px;flex-wrap:wrap}
.sec-head h4{font-size:13.5px;color:var(--ink);font-weight:700}
.sec-cnt{font-size:11px;color:var(--muted);margin-left:auto}

/* ---- 图谱：单元着色 / 关联虚线 / 知识点点阵 ---- */
.node.chap.u0 circle{fill:#fff;stroke:var(--accent);stroke-width:2.2}
.node.chap.u1 circle{fill:var(--accent-soft);stroke:var(--accent);stroke-width:2.2;stroke-opacity:.78}
.edge-link{stroke:#b9a5e8;stroke-width:1.6;fill:none;stroke-dasharray:6 5;opacity:.85}
.edge-link.cross{stroke:#eab892;stroke-dasharray:3 6}
.node.lk circle{fill:#fff;stroke:#b9a5e8;stroke-width:2}
.node.lk:hover circle{fill:#f5f0ff}
.lbl-no.sm{font-size:15px;fill:#7c5fb0}
.pt-dot{fill:var(--accent-2);stroke:var(--accent);stroke-width:.8;opacity:.9}

/* 详细模式按钮 */
.graph-hint .gh-toggle{font-size:12px;font-weight:700}
.graph-hint .gh-toggle.on{background:var(--accent);color:#fff;border-color:var(--accent)}

/* ---- 图谱右侧详情增强 ---- */
.gd-stats{display:grid;grid-template-columns:repeat(3,1fr);gap:6px;margin:11px 0}
.gd-stats div{
  background:#f8fafd;border:1px solid var(--line-2);border-radius:9px;
  padding:7px 4px;text-align:center;
}
.gd-stats b{display:block;font-size:17px;color:var(--accent);font-weight:800;line-height:1.2}
.gd-stats span{font-size:10.5px;color:var(--muted)}

.gd-secs{margin:11px 0}
.gd-secs b{font-size:11.5px;color:var(--muted);letter-spacing:.5px}
.gd-secs ol{margin:6px 0 0;padding:0;list-style:none;display:flex;flex-direction:column;gap:4px}
.gd-secs li{display:flex;gap:7px;font-size:12px;color:var(--ink-2);line-height:1.6}

.gd-links{margin:11px 0}
.gd-links b{font-size:11.5px;color:var(--muted);letter-spacing:.5px}
.gd-link-chips{display:flex;flex-wrap:wrap;gap:5px;margin-top:6px}
.gd-link-chip{
  padding:4px 9px;border-radius:7px;font-size:11.5px;font-weight:600;
  border:1px solid var(--line);background:#fff;color:var(--ink-2);transition:.15s;
}
.gd-link-chip:hover{border-color:var(--accent);color:var(--accent)}
.gd-link-chip.cross{border-style:dashed;color:#b45309;border-color:#fde68a;background:#fffbeb}

.gd-progress{font-size:12px;color:var(--muted);margin-top:9px}
.gd-done{color:var(--accent);font-weight:700}

.side-unit{
  grid-column:1/-1;font-size:11px;font-weight:800;color:var(--muted);
  letter-spacing:.8px;margin:8px 0 0;
}

/* ============================================================
   手机端：长页面按主题折叠 / 收藏（PC 端不生效）
   ============================================================ */
.block-body{margin-top:10px}

.mtoc-on .block{margin-top:14px}
.mtoc-on .block .block-title{margin-bottom:0}
.mtoc-on .block .block-body{margin-top:11px}
.mtoc-on .block.collapsed .block-body{display:none}
.mtoc-on .block.collapsed .block-title{margin-bottom:0}

.mtoc-bar{
  position:sticky;top:0;z-index:26;margin:0 0 12px;padding:9px 11px;
  background:rgba(255,255,255,.97);
  -webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);
  border:1px solid var(--line);border-radius:13px;
  box-shadow:0 3px 14px -8px rgba(22,33,58,.42);
}
.mtoc-row{display:flex;align-items:center;gap:8px}
.mtoc-row2{margin-top:7px;padding-top:7px;border-top:1px dashed var(--line-2)}
.mtoc-label{flex:0 0 auto;font-size:11px;font-weight:800;color:var(--muted);letter-spacing:.6px}
.mtoc-chips{display:flex;gap:6px;overflow-x:auto;scrollbar-width:none;flex:1 1 auto}
.mtoc-chips::-webkit-scrollbar{display:none}
.mtoc-chip{
  flex:0 0 auto;display:flex;align-items:center;gap:4px;
  padding:5px 11px;border-radius:20px;font-size:12px;font-weight:600;
  color:var(--muted);border:1px solid var(--line);background:#fff;white-space:nowrap;
}
.mtoc-chip i{font-style:normal;font-size:12px;line-height:1}
.mtoc-chip.on{background:var(--accent);border-color:var(--accent);color:#fff}
.mtoc-mini{
  padding:4px 11px;border-radius:8px;font-size:11.5px;font-weight:600;
  color:var(--muted);border:1px solid var(--line);background:#fff;
}
.mtoc-mini:active{background:var(--accent-soft);color:var(--accent)}
.mtoc-hint{margin-left:auto;font-size:10.5px;color:#a3adbd;white-space:nowrap}

.mtoc-tools{display:inline-flex;align-items:center;gap:6px;margin-left:auto;flex:0 0 auto}
.mtoc-fold{
  font-size:11px;font-weight:700;color:var(--accent);
  background:var(--accent-soft);border-radius:20px;padding:3px 11px;
}
.mtoc-fold:active{background:var(--accent-2)}
.mtoc-star{font-size:16px;line-height:1;color:#d3dbe6;padding:0 3px;transition:.15s}
.mtoc-star.on{color:#f59e0b}
.mtoc-star:active{transform:scale(1.2)}

@media (max-width:900px){
  .edition-bar{padding:8px 14px}
  .eb-meta{display:none}
  .eb-chip{padding:5px 12px;font-size:12.5px}
  .mtoc-on .block-title{flex-wrap:wrap;row-gap:6px}
  .gd-stats{grid-template-columns:repeat(3,1fr)}
}