:root{
  --bg:#F5F7FA; --card:#FFFFFF; --ink:#1F2937; --sub:#6B7280;
  --line:#E5E9F0; --blue:#2563EB; --blue-bg:#EFF4FF;
  --green:#16A34A; --green-bg:#EAF7EF;
  --red:#DC2626; --red-bg:#FDEEEC;
  --orange:#D97706; --orange-bg:#FFF6E6;
  --purple:#7C3AED; --purple-bg:#F4EFFD;
  --teal:#0E7C86; --teal-bg:#E6F4F4;
  --indigo:#4F46E5; --indigo-bg:#EEF0FE;
  --pink:#DB2777; --pink-bg:#FDF0F6;
  --cyan:#0891B2; --cyan-bg:#E0F7FA;
  --amber:#B45309; --amber-bg:#FFF3E0;
  --radius:16px; --shadow:0 1px 3px rgba(16,24,40,.06),0 4px 16px rgba(16,24,40,.05);
}
[data-theme="dark"]{--bg:#0F172A;--card:#1E293B;--ink:#E2E8F0;--sub:#94A3B8;--line:#334155;
  --blue-bg:#172554;--green-bg:#14532D;--red-bg:#450A0A;--orange-bg:#451A03;--purple-bg:#2E1065;
  --teal-bg:#164E63;--indigo-bg:#1E1B4B;--pink-bg:#500724;--cyan-bg:#164E63;--amber-bg:#431407;}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:116px}
body{margin:0;font-family:-apple-system,BlinkMacSystemFont,'PingFang SC','Microsoft YaHei','Segoe UI',Arial,sans-serif;font-size:15px;line-height:1.7;color:var(--ink);background:var(--bg)}
.bg-canvas{background:var(--bg)} .text-ink{color:var(--ink)} .antialiased{-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
button{font-family:inherit}
/* 顶栏 */
.topbar{position:fixed;top:0;left:0;right:0;height:60px;z-index:50;display:flex;align-items:center;gap:12px;padding:0 16px;background:rgba(255,255,255,.92);backdrop-filter:blur(8px);border-bottom:1px solid var(--line)}
[data-theme="dark"] .topbar{background:rgba(15,23,42,.92)}
.menu-btn{display:none;width:44px;height:44px;border:none;background:transparent;font-size:18px;cursor:pointer;color:var(--ink);border-radius:10px}
.brand{font-weight:700;font-size:15px;white-space:nowrap;color:var(--ink)}
.brand-sub{color:var(--blue);font-weight:600}
.search-wrap{flex:1;display:flex;justify-content:center;position:relative}
/* 首页全站搜索框（放大镜 + 主色描边）与章节页搜索框视觉区分 */
.search{width:100%;max-width:560px;height:40px;padding:0 14px;border:1px solid var(--line);border-radius:10px;background:var(--bg);color:var(--ink);font-size:14px;transition:border-color .18s,box-shadow .18s}
.search:focus{outline:none;border-color:var(--blue);box-shadow:0 0 0 3px rgba(37,99,235,.14)}
.search.search-global{max-width:620px;height:44px;padding:0 16px 0 42px;border:1.5px solid var(--blue);border-radius:14px;box-shadow:0 4px 16px rgba(37,99,235,.12);background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%232563EB' stroke-width='2.2' stroke-linecap='round' stroke-linejoin='round'%3E%3Ccircle cx='11' cy='11' r='7'/%3E%3Cpath d='m21 21-4.3-4.3'/%3E%3C/svg%3E");background-repeat:no-repeat;background-position:13px center;background-size:18px}
.search.search-global:focus{box-shadow:0 0 0 4px rgba(37,99,235,.18)}
.search.search-page:focus{border-color:var(--green);box-shadow:0 0 0 3px rgba(22,163,74,.14)}
.top-right{display:flex;align-items:center;gap:8px}
.hud{display:inline-flex;align-items:center;gap:7px;height:36px;padding:0 14px;border:1px solid var(--line);background:var(--card);border-radius:999px;color:var(--sub);font-size:12px;font-weight:500;white-space:nowrap;box-shadow:0 1px 4px rgba(16,24,40,.06)}
.hud::before{content:"";width:34px;height:6px;border-radius:999px;background-color:#E5E7EB;background-image:linear-gradient(135deg,#3B82F6,#2563EB);background-repeat:no-repeat;background-size:var(--pct,0%) 100%;flex:none}
.hud-btn{display:inline-flex;align-items:center;justify-content:center;height:36px;padding:0 16px;border:1px solid var(--line);background:var(--card);border-radius:999px;color:var(--ink);font-size:13px;font-weight:500;cursor:pointer;white-space:nowrap;transition:all .18s;box-shadow:0 1px 4px rgba(16,24,40,.06)}
.hud-btn:hover{border-color:var(--blue);color:var(--blue);transform:translateY(-1px)}
.hud-btn.btn-quiz{background:linear-gradient(135deg,#16A34A 0%,#15803D 100%);border-color:transparent;color:#fff;font-weight:600;box-shadow:0 4px 12px rgba(22,163,74,.28)}
.hud-btn.btn-quiz:hover{border-color:transparent;color:#fff;box-shadow:0 6px 16px rgba(22,163,74,.4)}
.hud-btn:active,.rp-btn:active,.ch-card:active{transform:scale(.98)}
/* 布局 */
.layout{padding-top:60px;display:flex;max-width:1440px;margin:0 auto}
.sidebar{width:240px;flex-shrink:0;position:sticky;top:60px;height:calc(100vh - 60px);overflow-y:auto;overscroll-behavior:contain;border-right:1px solid var(--line);background:var(--card);padding:12px}
.main{flex:1;min-width:0;padding:24px 28px 60px;max-width:940px}
.overlay{display:none;position:fixed;inset:0;background:rgba(15,23,42,.4);z-index:45}
/* 侧栏树 */
.tree-label{font-size:11px;color:var(--sub);text-transform:uppercase;letter-spacing:.05em;padding:6px 8px}
.tree{display:flex;flex-direction:column;gap:1px}
.tree-ch{margin:0 -4px}
.tree-head{display:flex;align-items:center;gap:6px;width:100%;padding:8px;border:none;background:transparent;border-radius:10px;cursor:pointer;font-size:13px;color:var(--ink);text-align:left}
.tree-head:hover{background:var(--bg)}
.tree-head .twisty{font-size:10px;color:var(--sub);transition:transform .15s;width:10px}
.tree-head .num{color:var(--sub);font-size:11px;width:18px;flex-shrink:0}
.tree-head .tt{flex:1;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.tree-head .cnt{font-size:10px;color:var(--sub);background:var(--bg);padding:1px 7px;border-radius:8px;flex-shrink:0}
.tree-ch.is-active>.tree-head{background:var(--blue-bg);color:var(--blue);font-weight:600}
.tree-ch.open>.tree-head .twisty{transform:rotate(90deg)}
.tree-secs{display:none;padding:2px 0 4px 24px;flex-direction:column}
.tree-ch.open .tree-secs{display:flex}
.tree-sec{display:flex;align-items:baseline;gap:6px;padding:5px 8px;font-size:12px;color:var(--sub);border-radius:8px}
.tree-sec .tkno{font-size:10px;color:var(--sub);flex-shrink:0;width:26px;font-variant-numeric:tabular-nums}
.tree-sec .tkt{flex:1;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.tree-sec:hover{color:var(--blue);background:var(--bg)}
/* Hero */
.hero{background:linear-gradient(135deg,#0F172A 0%,#1E3A8A 55%,#2563EB 120%);color:#fff;border-radius:20px;padding:34px 30px;margin-bottom:22px;position:relative;overflow:hidden}
.hero::after{content:"";position:absolute;right:-60px;top:-60px;width:240px;height:240px;border-radius:50%;background:radial-gradient(circle,rgba(255,255,255,.13),transparent 70%)}
.hero h1{margin:0 0 8px;font-size:26px;letter-spacing:.5px;line-height:1.4}
.hero .hero-kicker{display:inline-block;font-size:11.5px;letter-spacing:.12em;background:rgba(255,255,255,.14);border:1px solid rgba(255,255,255,.3);border-radius:14px;padding:2px 12px;margin-bottom:10px}
.hero .lead{opacity:.88;font-size:14px;max-width:680px;margin:0}
.hero .tags{margin-top:14px;display:flex;flex-wrap:wrap;gap:8px}
.hero .tags span{font-size:12px;background:rgba(255,255,255,.13);border:1px solid rgba(255,255,255,.28);border-radius:20px;padding:2px 12px}
.hero-badge{font-size:13px;background:rgba(255,255,255,.16);border:1px solid rgba(255,255,255,.3);border-radius:14px;padding:2px 12px;vertical-align:middle}
/* 锚点导航 */
.topbar-uds{position:sticky;top:60px;z-index:40;background:rgba(255,255,255,.78);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);border:1px solid var(--line);border-radius:16px;padding:6px;display:flex;gap:4px;overflow-x:auto;overscroll-behavior-x:contain;margin-bottom:20px;scrollbar-width:none;-ms-overflow-style:none}
.topbar-uds::-webkit-scrollbar{display:none}
[data-theme="dark"] .topbar-uds{background:rgba(15,23,42,.82)}
.topbar-uds a{flex:0 0 auto;font-size:13px;font-weight:500;color:var(--sub);padding:6px 15px;border-radius:11px;white-space:nowrap;transition:all .18s;border:1px solid transparent}
.topbar-uds a:hover{background:var(--card);color:var(--blue);border-color:var(--line)}
.topbar-uds a.active{background:linear-gradient(135deg,var(--blue) 0%,#1D4ED8 100%);color:#fff;border-color:transparent;box-shadow:0 3px 12px rgba(37,99,235,.32)}
.topbar-uds.theme-teal a.active{background:linear-gradient(135deg,var(--teal),#0B5F66);box-shadow:0 3px 12px rgba(14,124,134,.32)}
.topbar-uds.theme-purple a.active{background:linear-gradient(135deg,var(--purple),#5B21B6);box-shadow:0 3px 12px rgba(124,58,237,.32)}
.topbar-uds.theme-orange a.active{background:linear-gradient(135deg,var(--orange),#B45309);box-shadow:0 3px 12px rgba(217,119,6,.32)}
.topbar-uds.theme-green a.active{background:linear-gradient(135deg,var(--green),#15803D);box-shadow:0 3px 12px rgba(22,163,74,.32)}
.topbar-uds.theme-red a.active{background:linear-gradient(135deg,var(--red),#991B1B);box-shadow:0 3px 12px rgba(220,38,38,.32)}
.topbar-uds.theme-indigo a.active{background:linear-gradient(135deg,var(--indigo),#3730A3);box-shadow:0 3px 12px rgba(79,70,229,.32)}
.topbar-uds.theme-pink a.active{background:linear-gradient(135deg,var(--pink),#9D174D);box-shadow:0 3px 12px rgba(219,39,119,.32)}
.topbar-uds.theme-cyan a.active{background:linear-gradient(135deg,var(--cyan),#0E7490);box-shadow:0 3px 12px rgba(8,145,178,.32)}
.topbar-uds.theme-amber a.active{background:linear-gradient(135deg,var(--amber),#92400E);box-shadow:0 3px 12px rgba(180,83,9,.32)}
/* 小节整合区块 */
.sec-block{background:var(--card);border:1px solid var(--line);border-radius:16px;padding:20px 24px;margin-bottom:16px;box-shadow:var(--shadow);border-left:4px solid var(--blue)}
.sec-block.theme-teal{border-left-color:var(--teal)} .sec-block.theme-purple{border-left-color:var(--purple)}
.sec-block.theme-orange{border-left-color:var(--orange)} .sec-block.theme-green{border-left-color:var(--green)}
.sec-block.theme-red{border-left-color:var(--red)} .sec-block.theme-indigo{border-left-color:var(--indigo)}
.sec-block.theme-pink{border-left-color:var(--pink)} .sec-block.theme-cyan{border-left-color:var(--cyan)}
.sec-block.theme-amber{border-left-color:var(--amber)}
h2.sec{font-size:19px;margin:0 0 14px;display:flex;align-items:center;gap:10px;flex-wrap:wrap}
h2.sec .no{display:inline-flex;align-items:center;justify-content:center;min-width:52px;height:32px;border-radius:10px;background:var(--blue);color:#fff;font-size:13px;font-weight:700}
.theme-teal h2.sec .no{background:var(--teal)} .theme-purple h2.sec .no{background:var(--purple)}
.theme-orange h2.sec .no{background:var(--orange)} .theme-green h2.sec .no{background:var(--green)}
.theme-red h2.sec .no{background:var(--red)} .theme-indigo h2.sec .no{background:var(--indigo)}
.theme-pink h2.sec .no{background:var(--pink)} .theme-cyan h2.sec .no{background:var(--cyan)}
.theme-amber h2.sec .no{background:var(--amber)}
.done-btn{width:30px;height:30px;border:1px solid var(--line);background:var(--card);border-radius:999px;color:var(--sub);font-size:15px;font-weight:600;line-height:1;cursor:pointer;flex-shrink:0;margin-left:auto;transition:all .15s;display:inline-flex;align-items:center;justify-content:center}
.done-btn:hover{border-color:var(--green);color:var(--green)}
.done-btn.done{background:var(--green);border-color:var(--green);color:#fff;box-shadow:0 0 0 3px rgba(34,197,94,.18)}
.sec-block h3{font-size:16.5px;margin:22px 0 10px;padding-left:10px;border-left:3px solid var(--blue);line-height:1.5}
.theme-teal .sec-block h3,.sec-block.theme-teal h3{border-left-color:var(--teal)} .theme-purple .sec-block h3,.sec-block.theme-purple h3{border-left-color:var(--purple)}
.theme-orange .sec-block h3,.sec-block.theme-orange h3{border-left-color:var(--orange)} .theme-green .sec-block h3,.sec-block.theme-green h3{border-left-color:var(--green)}
.theme-red .sec-block h3,.sec-block.theme-red h3{border-left-color:var(--red)} .theme-indigo .sec-block h3,.sec-block.theme-indigo h3{border-left-color:var(--indigo)}
.theme-pink .sec-block h3,.sec-block.theme-pink h3{border-left-color:var(--pink)} .theme-cyan .sec-block h3,.sec-block.theme-cyan h3{border-left-color:var(--cyan)}
.theme-amber .sec-block h3,.sec-block.theme-amber h3{border-left-color:var(--amber)}
.sec-block h4{font-size:15px;margin:16px 0 8px}
.sec-block p{margin:9px 0;line-height:1.75}
.sec-block ul,.sec-block ol{margin:8px 0 12px;padding-left:24px}
.sec-block li{margin:4px 0}
.sec-block strong{font-weight:700}
.sec-block em{color:var(--sub)}
.sec-block hr{border:none;border-top:1px dashed var(--line);margin:18px 0}
code{font-family:'Cascadia Code','JetBrains Mono',Consolas,monospace;background:#EEF2F7;color:#B91C1C;border-radius:5px;padding:1px 6px;font-size:13px}
[data-theme="dark"] code{background:#1E293B;color:#F87171}
pre{background:#0F172A;color:#E5EDF5;border-radius:12px;padding:14px 16px;overflow-x:auto;overscroll-behavior-x:contain;font-size:12.5px;line-height:1.65;margin:12px 0}
pre code{background:none;color:inherit;padding:0}
/* 表格 */
.table-scroll{overflow-x:auto;overscroll-behavior-x:contain;margin:12px 0}
table{border-collapse:collapse;width:100%;font-size:13.5px;min-width:480px;background:var(--card);border:1px solid var(--line);border-radius:12px;overflow:hidden}
th{background:#F1F5FB;color:#1E293B;text-align:left;padding:9px 12px;border-bottom:1px solid var(--line);white-space:nowrap;font-size:12.5px}
[data-theme="dark"] th{background:#1E293B;color:#E2E8F0}
td{padding:8px 12px;border-bottom:1px solid var(--line);vertical-align:top}
tr:last-child td{border-bottom:none}
tr:hover td{background:#F8FAFD}
[data-theme="dark"] tr:hover td{background:#1E293B}
/* 提示框 */
.note{border-radius:12px;padding:11px 15px;margin:12px 0;font-size:13.5px;border-left:4px solid}
.note.info{background:var(--blue-bg);border-color:var(--blue)}
.note.ok{background:var(--green-bg);border-color:var(--green)}
.note.warn{background:var(--orange-bg);border-color:var(--orange)}
.note.err{background:var(--red-bg);border-color:var(--red)}
/* 代码块 */
.code-block{background:#0F172A;border-radius:12px;margin:12px 0;overflow:hidden}
.code-head{display:flex;align-items:center;gap:10px;padding:9px 14px;color:#94A3B8;font-size:12px;border-bottom:1px solid #1E293B}
.code-lang{margin-left:auto;text-transform:uppercase;font-size:11px}
.copy-btn{background:#334155;border:none;color:#E2E8F0;border-radius:8px;padding:3px 10px;font-size:12px;cursor:pointer;height:32px}
.copy-btn.copied{background:var(--green);color:#fff}
.code-block pre{margin:0;padding:14px 16px;overflow-x:auto}
.code-block code{font-family:ui-monospace,Consolas,monospace;font-size:13px;color:#E2E8F0;white-space:pre;background:none}
.hl .c{color:#64748B;font-style:italic}.hl .s{color:#FBBF24}.hl .n{color:#F472B6}.hl .k{color:#38BDF8;font-weight:600}
/* 图片 */
.kp-img{margin:14px 0;background:var(--card);border:1px solid var(--line);border-radius:12px;padding:10px}
.kp-img img{display:block;max-width:100%;max-height:720px;height:auto;margin:0 auto;border-radius:8px;cursor:zoom-in}
.kp-img figcaption{font-size:12px;color:var(--sub);text-align:center;margin-top:8px}
/* 首页 */
.stats-strip{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;margin:0 0 20px}
.stat{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:14px;text-align:center;box-shadow:var(--shadow)}
.stat b{display:block;font-size:22px;color:var(--blue)}
.stat span{font-size:12px;color:var(--sub)}
.quick-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:12px;margin-bottom:20px}
.quick-card{display:flex;align-items:center;gap:14px;background:var(--card);border:1px solid var(--line);border-radius:14px;padding:16px;box-shadow:var(--shadow);transition:transform .15s,box-shadow .15s}
.quick-card:hover{transform:translateY(-2px);box-shadow:0 6px 18px rgba(37,99,235,.12)}
.quick-ico{width:44px;height:44px;border-radius:12px;display:flex;align-items:center;justify-content:center;font-size:22px;flex-shrink:0}
.quick-uds .quick-ico{background:var(--blue-bg)}
.quick-quiz .quick-ico{background:var(--green-bg)}
.quick-t{font-size:14.5px;font-weight:700}
.quick-d{font-size:12px;color:var(--sub);margin-top:2px}
.ch-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:14px}
.ch-card{background:var(--card);border:1px solid var(--line);border-radius:16px;padding:16px;transition:transform .15s,box-shadow .15s,border-color .15s;display:block;box-shadow:var(--shadow);border-top:3px solid var(--blue)}
.ch-card:hover{transform:translateY(-2px);box-shadow:0 6px 18px rgba(16,24,40,.08)}
.ch-card.theme-teal{border-top-color:var(--teal)} .ch-card.theme-purple{border-top-color:var(--purple)}
.ch-card.theme-orange{border-top-color:var(--orange)} .ch-card.theme-green{border-top-color:var(--green)}
.ch-card.theme-red{border-top-color:var(--red)} .ch-card.theme-indigo{border-top-color:var(--indigo)}
.ch-card.theme-pink{border-top-color:var(--pink)} .ch-card.theme-cyan{border-top-color:var(--cyan)}
.ch-card.theme-amber{border-top-color:var(--amber)}
.ch-card-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:6px}
.ch-id{font-weight:700;color:var(--blue);font-size:12px}
.ch-card.theme-teal .ch-id{color:var(--teal)} .ch-card.theme-purple .ch-id{color:var(--purple)}
.ch-card.theme-orange .ch-id{color:var(--orange)} .ch-card.theme-green .ch-id{color:var(--green)}
.ch-card.theme-red .ch-id{color:var(--red)} .ch-card.theme-indigo .ch-id{color:var(--indigo)}
.ch-card.theme-pink .ch-id{color:var(--pink)} .ch-card.theme-cyan .ch-id{color:var(--cyan)}
.ch-card.theme-amber .ch-id{color:var(--amber)}
.ch-count{font-size:11px;color:var(--sub)}
.ch-title{font-size:14.5px;font-weight:600;line-height:1.4;margin-bottom:4px}
.ch-desc{font-size:12px;color:var(--sub);margin-bottom:10px;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.ch-prog{height:5px;background:var(--bg);border-radius:999px;overflow:hidden}
.ch-prog-bar{height:100%;width:0;background:var(--green);border-radius:999px;transition:width .2s}
/* 页脚与分页 */
.footer{text-align:center;color:var(--sub);font-size:12px;padding:24px;border-top:1px solid var(--line);background:var(--card)}
.chapter-pager{display:flex;justify-content:space-between;gap:12px;margin:26px 0 8px}
.chapter-pager a{flex:1;background:var(--card);border:1px solid var(--line);border-radius:14px;padding:12px 16px;font-size:14px;color:var(--ink);line-height:1.4;box-shadow:var(--shadow)}
.chapter-pager a:hover{border-color:var(--blue);color:var(--blue)}
.chapter-pager .cp-next{text-align:right}
.chapter-pager span{display:block;font-size:12px;color:var(--sub);margin-top:2px}
/* 弹层 */
.popover{position:fixed;z-index:100;max-width:320px;background:var(--card);border:1px solid var(--blue);border-radius:12px;padding:8px 12px;font-size:13px;box-shadow:0 6px 20px rgba(15,23,42,.12)}
.popover b{color:var(--blue)}
.lightbox{display:none;position:fixed;inset:0;z-index:200;background:rgba(0,0,0,.85);align-items:center;justify-content:center;cursor:zoom-out}
.lightbox.open{display:flex}
.lightbox img{max-width:94vw;max-height:92vh;border-radius:8px}
.lb-close{position:absolute;top:14px;right:22px;color:#fff;font-size:30px;cursor:pointer}
/* 移动端 */
@media (max-width:1023px){
  .menu-btn{display:block}
  .sidebar{position:fixed;left:0;top:60px;bottom:0;z-index:46;transform:translateX(-100%);transition:transform .2s}
  .sidebar.open{transform:translateX(0)}
  .overlay.show{display:block}
  .main{padding:18px 14px 50px}
  .stats-strip{grid-template-columns:repeat(2,1fr)}
  .quick-grid{grid-template-columns:1fr}
  .search{max-width:none}
  .sec-block{padding:16px}
}
/* 侧栏小节高亮（scroll-spy） */
.tree-sec.active{background:var(--blue-bg);color:var(--blue);font-weight:600}
/* 回到顶部按钮 */
.to-top{position:fixed;right:22px;bottom:26px;z-index:120;width:48px;height:48px;border-radius:999px;border:none;background:linear-gradient(135deg,var(--blue) 0%,#1D4ED8 100%);color:#fff;font-size:21px;font-weight:600;cursor:pointer;box-shadow:0 8px 20px rgba(37,99,235,.35);opacity:0;transform:translateY(12px);pointer-events:none;transition:opacity .2s,transform .2s,box-shadow .2s}
.to-top.show{opacity:1;transform:translateY(0);pointer-events:auto}
.to-top:hover{background:linear-gradient(135deg,#3B82F6 0%,#2563EB 100%);box-shadow:0 10px 24px rgba(37,99,235,.45)}
.to-top:active{transform:scale(.94)}
/* 术语 Tooltip */
.tip{background:var(--blue-bg);color:var(--blue);border-radius:3px;padding:0 2px;font-weight:600;cursor:help;text-decoration:underline;text-decoration-color:var(--blue);text-decoration-thickness:1px;text-underline-offset:1px}
.term{color:var(--blue);font-weight:600}
[data-theme="dark"] .tip,[data-theme="dark"] .term{color:#93C5FD}
[data-theme="dark"] .tip{text-decoration-color:#93C5FD}
.kb-tip{position:fixed;z-index:300;max-width:340px;background:#0F172A;border:1px solid rgba(148,163,184,.35);border-radius:10px;padding:9px 12px;font-size:12.5px;line-height:1.55;color:#E2E8F0;box-shadow:0 10px 28px rgba(15,23,42,.35);pointer-events:none;opacity:0;transform:translateY(5px);transition:opacity .14s ease,transform .14s ease}
.kb-tip.show{opacity:1;transform:translateY(0)}
.kb-tip b{color:#93C5FD;margin-right:4px}
.kb-tip .kb-full{display:block;color:#CBD5E1;font-weight:600}
.kb-tip .kb-desc{display:block;color:#94A3B8;margin-top:3px}



/* ===== 搜索：全站下拉面板 / 章节高亮定位条 ===== */
.search-panel{position:absolute;top:calc(100% + 8px);left:50%;transform:translateX(-50%);width:min(680px,calc(100vw - 32px));max-height:62vh;overflow:auto;overscroll-behavior:contain;background:var(--card);border:1px solid var(--line);border-radius:16px;box-shadow:0 18px 44px rgba(15,23,42,.16);z-index:130;display:none;padding:10px 8px 12px}
.search-panel.open{display:block}
.sp-head{font-size:12px;color:var(--sub);padding:4px 10px 8px;border-bottom:1px solid var(--line);margin-bottom:4px}
.sp-group{font-size:11px;font-weight:700;color:var(--blue);padding:9px 10px 3px;letter-spacing:.04em}
.sp-item{display:block;padding:8px 10px;border-radius:10px;text-decoration:none;color:inherit}
.sp-item:hover{background:var(--blue-bg,#EFF6FF)}
.sp-title{display:block;font-size:13.5px;font-weight:600;color:var(--ink);line-height:1.5}
.sp-snip{display:block;font-size:12px;color:var(--sub);margin-top:2px;line-height:1.6;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.sp-empty{padding:18px 12px;text-align:center;color:var(--sub);font-size:13px}
mark.hit{background:#FDE68A;color:#92400E;border-radius:3px;padding:0 1px}
.sp-item mark.hit{background:#FDE047;color:#78350F}
mark.hit.cur{background:#F59E0B;color:#fff;outline:2px solid rgba(245,158,11,.35)}
.search-hud{position:fixed;top:70px;left:50%;transform:translate(-50%,-8px);z-index:120;display:none;align-items:center;gap:8px;background:var(--card);border:1px solid var(--line);border-radius:999px;padding:6px 10px;box-shadow:0 10px 26px rgba(15,23,42,.16);opacity:0;transition:opacity .18s,transform .18s}
.search-hud.show{display:flex;opacity:1;transform:translate(-50%,0)}
.sh-count{font-size:12px;color:var(--ink);font-weight:600;padding:0 6px;white-space:nowrap}
.sh-btn{border:1px solid var(--line);background:var(--bg);border-radius:999px;padding:4px 12px;font-size:12px;color:var(--sub);cursor:pointer;white-space:nowrap}
.sh-btn:hover{color:var(--blue);border-color:var(--blue)}
.sh-clear{color:#DC2626}