/* 教材章节课件 · 共享外壳样式(所有章节同一份,Worker 不改) */
:root{--bg:#f4f5f1;--paper:#fff;--ink:#17343c;--muted:#667b80;--line:#dce5e1;--soft:#eef3ef;--teal:#22786f;--teal2:#40a79b;--navy:#213d52;--gold:#b28036;--purple:#7a5ea8;--red:#b9573f;--blue:#3d6fa8;--mono:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;--sans:-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:24px}
body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--sans);font-size:16px;line-height:1.85;-webkit-font-smoothing:antialiased}
a{color:var(--teal);text-decoration:none}a:hover{text-decoration:underline}
button{font:inherit;cursor:pointer;border:1px solid #cadbd5;background:#fff;color:var(--teal);padding:6px 13px;border-radius:8px;font-size:13px;line-height:1.5}
button:hover{background:#eef7f2}button:focus-visible,a:focus-visible,summary:focus-visible,input:focus-visible{outline:3px solid var(--teal2);outline-offset:3px}
button.primary{background:var(--teal);color:#fff;border-color:var(--teal)}button.primary:hover{background:#1b655d}
img{max-width:100%}
/* ---------- 侧栏 ---------- */
#kc-progress{position:fixed;top:0;left:0;height:3px;background:linear-gradient(90deg,var(--teal),var(--gold));width:0;z-index:30}
aside.kc-aside{position:fixed;inset:0 auto 0 0;width:268px;background:#fbfcfa;border-right:1px solid var(--line);padding:30px 20px 24px;overflow:auto;z-index:20}
.brand{font-weight:760;font-size:19px;line-height:1.45;letter-spacing:.02em}
.brand small{font-family:var(--mono);display:block;font-size:10px;letter-spacing:.14em;margin:8px 0 22px;color:var(--muted);font-weight:500}
nav.kc-nav a{display:flex;gap:10px;align-items:baseline;color:#5b7074;border-radius:7px;margin:2px -8px;padding:7px 8px;font-size:13.5px;line-height:1.5}
nav.kc-nav a b{font-family:var(--mono);font-size:11px;font-weight:500;color:#93a3a3;flex:0 0 auto}
nav.kc-nav a.sub{font-size:12.5px;padding:4px 8px 4px 30px;color:#71868a}
nav.kc-nav a.active{background:#e6f1eb;color:#176b60;font-weight:650}nav.kc-nav a:hover{text-decoration:none;background:var(--soft)}
nav.kc-nav .grp{display:none}nav.kc-nav .grp.open{display:block}
.aside-bottom{margin-top:24px;border-top:1px solid var(--line);padding-top:16px;font-size:11.5px;color:var(--muted);line-height:1.8}
.aside-bottom button{margin:8px 6px 0 0}
.offline-dot{width:6px;height:6px;background:#3b9783;display:inline-block;border-radius:50%;margin-right:7px}
main.kc-main{max-width:1180px;padding:44px 56px 90px;margin-left:268px}
/* ---------- 章首 ---------- */
.eyebrow{font:11px var(--mono);letter-spacing:.15em;color:var(--teal);margin-bottom:16px;text-transform:uppercase}
.hero h1{font-size:clamp(32px,3.6vw,50px);font-weight:780;line-height:1.28;letter-spacing:-.03em;margin:0 0 18px}
.hero h1 em{font-style:normal;color:var(--teal)}
.hero .lead{max-width:820px;font-size:17px;color:var(--muted);margin:0 0 22px}
.pills{display:flex;gap:8px;flex-wrap:wrap;margin:10px 0}.pill{border:1px solid #d6e2dc;border-radius:30px;padding:3px 12px;font-size:12px;background:#fafcf9;color:#4e6d68}
.principles{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:16px;margin:28px 0 18px}
.principles article{background:#fff;border:1px solid var(--line);padding:20px;border-radius:12px}
.principles .n{color:#83a29b;font:12px var(--mono)}.principles h3{font-size:16.5px;margin:8px 0 6px}.principles p{font-size:14px;color:var(--muted);margin:0}
.legend{display:flex;flex-wrap:wrap;gap:16px;font-size:12px;color:#6d8283;margin-top:16px}.legend i{display:inline-block;width:10px;height:10px;border:1px solid;border-radius:3px;margin-right:5px;vertical-align:-1px}
.timeline{list-style:none;padding:0;margin:20px 0;display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:12px;counter-reset:tl}
.timeline li{background:#fff;border:1px solid var(--line);border-radius:12px;padding:14px 16px;font-size:14px;counter-increment:tl;position:relative}
.timeline li::before{content:counter(tl,decimal-leading-zero);font:11px var(--mono);color:var(--gold);display:block;margin-bottom:4px}
/* ---------- 节 ---------- */
section.lesson,section.chapter-open,section.chapter-end{margin-top:64px}
section.chapter-open{margin-top:0}
.lesson-head{border-bottom:1px solid var(--line);padding-bottom:20px;margin-bottom:8px}
.lesson-head .no{font:12px var(--mono);color:#8a9c97;letter-spacing:.1em}
.lesson-head h2,section.chapter-end>h2{font-size:30px;letter-spacing:-.02em;margin:6px 0 8px;line-height:1.35}
.lesson-head .lead{color:var(--muted);max-width:860px;margin:0}
.goals{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:10px;list-style:none;padding:0;margin:18px 0}
.goals li{background:#f7faf8;border:1px solid var(--line);border-radius:10px;padding:10px 14px 10px 38px;font-size:14px;position:relative}
.goals li::before{content:"◎";position:absolute;left:14px;top:10px;color:var(--teal)}
article.unit{margin-top:44px}
article.unit>h3{font-size:23px;margin:0 0 12px;padding-left:14px;border-left:4px solid var(--teal);line-height:1.45}
article.unit h4{font-size:18px;margin:30px 0 10px;color:var(--navy)}
article.unit h5{font-size:16px;margin:22px 0 8px;color:#3a5a60}
p{margin:12px 0}
.prose{max-width:900px}
.kc-main ul,.kc-main ol{padding-left:1.6em}.kc-main li{margin:4px 0}
table.data{border-collapse:collapse;font-size:14px;background:#fff;margin:14px 0;min-width:50%}
table.data th{background:#ecf1ed;padding:9px 14px;font-weight:600;color:#47635f;border:1px solid #dfe8e3;text-align:center}
table.data td{padding:9px 14px;border:1px solid #e7ede8;text-align:center}
.table-wrap{overflow-x:auto;margin:14px 0}
code{font-family:var(--mono);font-size:.88em;background:#eaf0eb;border-radius:4px;padding:1px 5px}
mark{background:#fbedc9;color:inherit;padding:0 3px;border-radius:3px}
.key{color:var(--teal);font-weight:650}.warn-t{color:var(--red);font-weight:650}
/* ---------- 卡片 ---------- */
.card{background:#fff;border:1px solid var(--line);border-radius:14px;padding:18px 22px;margin:20px 0;position:relative}
.card>.tag{display:inline-block;font-size:12px;font-weight:650;letter-spacing:.06em;border-radius:6px;padding:1px 9px;margin-bottom:6px}
.card>h4,.card>h5{margin:4px 0 8px!important;font-size:17px}
.card.def{border-left:5px solid var(--teal);background:#f6fbf9}.card.def>.tag{background:#dff0ea;color:#176b60}
.card.thm{border-left:5px solid var(--navy);background:#f6f8fb}.card.thm>.tag{background:#e2e9f2;color:var(--navy)}
.card.explore{border-left:5px solid var(--gold);background:#fffaf1}.card.explore>.tag{background:#f6e7c8;color:#80612b}
.card.think{border-left:5px solid var(--purple);background:#faf8fd}.card.think>.tag{background:#ece5f6;color:#5f4790}
.card.note{border-left:5px solid var(--red);background:#fdf7f5}.card.note>.tag{background:#f6e1da;color:#97462f}
.card.method{border-left:5px solid var(--blue);background:#f5f8fc}.card.method>.tag{background:#dfe8f4;color:#2e5a8e}
.card.history{border-left:5px solid #8c7a5b;background:#fbf9f5}.card.history>.tag{background:#ece5d8;color:#6c5c40}
.card.tech{border-left:5px solid #4b8a9e;background:#f4f9fb}.card.tech>.tag{background:#dcecf1;color:#2f6a7c}
.card.summary{border:1px dashed #b6cfc6;background:#fbfdfb}.card.summary>.tag{background:#e6f1eb;color:#176b60}
.card .formula{font-size:1.08em;text-align:center;margin:10px 0}
.compare{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:14px;margin:18px 0}
.compare>div{background:#fff;border:1px solid var(--line);border-radius:12px;padding:14px 18px}
.compare>div>b:first-child{display:block;color:var(--navy);margin-bottom:6px}
.callout{border-left:3px solid #4b9988;background:#eaf3ec;padding:14px 20px;border-radius:0 9px 9px 0;margin:20px 0;font-size:14.5px;color:#426860}
.callout strong{color:#1c6258}.callout.amber{background:#f9f0df;border-color:#c09146;color:#82683a}.callout.amber strong{color:#8c632b}
/* ---------- 例题 ---------- */
.example{background:#fff;border:1px solid #d5e2dd;border-radius:14px;margin:24px 0;overflow:hidden}
.example>.ex-head{display:flex;gap:12px;align-items:center;padding:12px 20px;background:#f2f7f4;border-bottom:1px solid #e1ebe6}
.example>.ex-head .ex-no{font-weight:760;color:#fff;background:var(--teal);border-radius:7px;padding:1px 10px;font-size:14px;white-space:nowrap}
.example>.ex-head .ex-title{font-weight:650;color:var(--navy);font-size:15px}
.example>.ex-head .ex-tools{margin-left:auto;display:flex;gap:6px}
.example>.ex-q{padding:14px 22px 4px}
.example>.ex-idea{margin:4px 22px 0;padding:8px 14px;background:#fffaf1;border-radius:8px;font-size:14.5px;color:#6d5a33}
.example>.ex-idea::before{content:"思路 ";font-weight:700;color:var(--gold)}
.example ol.steps{list-style:none;counter-reset:st;margin:8px 22px 6px;padding:0}
.example ol.steps>li{counter-increment:st;position:relative;padding:8px 6px 8px 44px;border-top:1px dashed #e3ebe7;transition:opacity .25s}
.example ol.steps>li::before{content:counter(st);position:absolute;left:6px;top:10px;width:24px;height:24px;border-radius:50%;background:#e1f0eb;color:#176b60;font:600 12px/24px var(--mono);text-align:center}
.example ol.steps>li.hidden{display:none}
.example>.ex-reflect{margin:4px 22px 16px;padding:10px 14px;border-left:3px solid var(--purple);background:#faf8fd;font-size:14.5px}
.example>.ex-reflect::before{content:"反思 ";font-weight:700;color:var(--purple)}
.example>.ex-foot{padding:0 22px 14px}
/* ---------- 练习 ---------- */
.practice{background:#fbfcfa;border:1px solid var(--line);border-radius:14px;padding:16px 22px;margin:26px 0}
.practice>h4{margin:0 0 6px!important;font-size:17px;color:var(--navy)}
.practice>h4::before{content:"✎ ";color:var(--teal)}
.practice h5{color:var(--gold)!important;font-size:14.5px!important;letter-spacing:.06em;margin:16px 0 4px!important}
ol.problems{margin:6px 0;padding-left:1.8em}ol.problems>li{margin:12px 0;padding-left:4px}
details.ans{margin:6px 0 2px;font-size:14.5px}
details.ans>summary{cursor:pointer;color:var(--teal);font-size:13px;width:max-content;list-style:none;border:1px solid #cfe1da;border-radius:6px;padding:0 10px}
details.ans>summary::-webkit-details-marker{display:none}
details.ans[open]>summary{background:#e6f1eb}
details.ans>div{background:#f5faf7;border-radius:8px;padding:8px 14px;margin-top:6px}
.level{display:inline-block;font-size:11px;border-radius:4px;padding:0 6px;margin-left:6px;vertical-align:2px}
.level.l1{background:#e1f0eb;color:#176b60}.level.l2{background:#f6e7c8;color:#80612b}.level.l3{background:#f6e1da;color:#97462f}
/* ---------- 图卡 ---------- */
figure.diagram-card{margin:24px 0;background:var(--paper);border:1px solid var(--line);border-radius:15px;overflow:hidden;box-shadow:0 2px 5px #17343c05}
figure.diagram-card>figcaption{display:flex;gap:14px;padding:18px 24px 8px;align-items:flex-start}
.fig-number{font:12px var(--mono);display:grid;place-items:center;flex:0 0 auto;min-width:44px;padding:0 7px;white-space:nowrap;height:30px;border:1px solid #d6e4df;border-radius:8px;color:var(--teal);margin-top:2px}
figure.diagram-card figcaption h4{font-size:17px!important;margin:0 0 3px!important;line-height:1.5;color:var(--ink)}
figure.diagram-card figcaption p{margin:0;font-size:13.5px;color:var(--muted)}
.fig-kind{font:10px var(--mono);letter-spacing:.1em;color:#93a3a3;margin-left:auto;white-space:nowrap;padding-top:4px}
.mermaid-wrap{overflow:auto;padding:14px 20px 18px;text-align:center;background:radial-gradient(circle,#dfe8e4 1px,transparent 1.2px) 0 0/20px 20px,#fcfdfc;border-top:1px solid #eef2ef}
.mermaid-wrap svg{max-width:100%;height:auto}
.mermaid-wrap.is-scroll{text-align:left;position:relative}.mermaid-wrap.is-scroll::after{content:"← 左右滑动查看完整图 →";display:block;position:sticky;left:0;font-size:11px;color:#93a09e;text-align:center;padding-top:8px}
@media print{.mermaid-wrap svg{width:100%!important;max-width:100%!important}.mermaid-wrap.is-scroll::after{display:none}}
pre.mermaid{margin:0;font-size:0;color:transparent}
.mermaid-source{border-top:1px solid #e9efeb}
.mermaid-source summary{cursor:pointer;padding:10px 24px;font-size:12px;color:var(--teal)}
.mermaid-source summary span{color:#93a09e;margin-left:10px;font-size:11px}
.mermaid-source pre{font-size:11.5px;line-height:1.7;overflow:auto;background:#f5f8f6;padding:14px 22px;margin:6px 20px 16px;border-radius:8px;color:#3d5c61;white-space:pre}
.source-tools{display:flex;align-items:center;gap:12px;padding:0 22px}.copy-state{font-size:12px;color:var(--teal)}
.jsx-stage{display:grid;grid-template-columns:minmax(0,1fr) 260px;gap:0;border-top:1px solid #eef2ef}
.jsx-stage.wide{grid-template-columns:1fr}
/* 动图画板:高度封顶(--jh),宽度随比例同步收窄并居中,避免方形图撑满整栏 */
.jsx-board{--r:1.6;--jh:min(58vh,500px);width:min(100%,calc(var(--jh)*var(--r)));aspect-ratio:var(--r);margin:0 auto;background:#fff}
.jsx-board[data-ratio="1"]{--r:1;--jh:min(58vh,460px)}.jsx-board[data-ratio="4/3"]{--r:1.3333}.jsx-board[data-ratio="1.5"]{--r:1.5}.jsx-board[data-ratio="2"]{--r:2}
@media print{.jsx-board{--jh:420px}}
.jsx-controls{border-left:1px solid #eef2ef;padding:14px 16px;font-size:13.5px;background:#fbfcfa;display:flex;flex-direction:column;gap:10px}
.jsx-stage.wide .jsx-controls{border-left:0;border-top:1px solid #eef2ef;flex-direction:row;flex-wrap:wrap;align-items:center}
.jsx-controls:empty{display:none}
.kc-ctl{display:flex;flex-direction:column;gap:2px}.kc-ctl label{font-size:12.5px;color:var(--muted);display:flex;justify-content:space-between;gap:8px}
.kc-ctl label output{font-family:var(--mono);color:var(--teal);font-weight:600}
.kc-ctl input[type=range]{width:100%;accent-color:var(--teal)}
.kc-btns{display:flex;flex-wrap:wrap;gap:6px}
.kc-readout{background:#fff;border:1px solid var(--line);border-radius:8px;padding:8px 10px;font-size:13.5px;line-height:1.7;min-height:2em}
.jsx-hint{font-size:12px;color:#8a9c97;padding:6px 24px 12px}
.tikz-wrap{padding:6px 24px 18px;text-align:center}
.tikz-wrap img{max-height:560px;cursor:zoom-in;border-radius:6px}
.tikz-row{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:14px;align-items:end}
.photo-wrap{padding:6px 24px 18px;text-align:center}.photo-wrap img{max-height:380px;border-radius:8px}
figure.diagram-card>.fig-note{font-size:13px;color:#5b7074;padding:0 24px 16px;margin:0}
figure[data-state=error]{border-color:#e2a593}
figure[data-state=error]::after{content:"该图渲染失败";display:block;color:var(--red);font-size:12px;padding:6px 24px}
.pending-fig{display:grid;place-items:center;min-height:180px;color:#a0b0ad;font-size:13px;background:repeating-linear-gradient(45deg,#fafbfa,#fafbfa 10px,#f3f6f4 10px,#f3f6f4 20px)}
/* ---------- 灯箱 / 打印 / 窄屏 ---------- */
#kc-lightbox{position:fixed;inset:0;background:#0f2228e6;display:none;place-items:center;z-index:50;cursor:zoom-out;padding:3vw}
#kc-lightbox.on{display:grid}#kc-lightbox img{max-width:94vw;max-height:92vh;background:#fff;border-radius:8px}
.kc-footer{margin-top:80px;border-top:1px solid var(--line);padding-top:18px;font-size:12px;color:var(--muted)}
@media (max-width:980px){aside.kc-aside{position:static;width:auto;border-right:0;border-bottom:1px solid var(--line);max-height:none}main.kc-main{margin-left:0;padding:28px 20px 70px}.jsx-stage{grid-template-columns:1fr}.jsx-controls{border-left:0;border-top:1px solid #eef2ef}nav.kc-nav a.sub{display:none}}
@media print{aside.kc-aside,#kc-progress,.ex-tools,.mermaid-source,.source-tools{display:none!important}main.kc-main{margin:0;padding:0;max-width:none}.example ol.steps>li.hidden{display:block}details.ans{display:block}details.ans>div{display:block}figure,.card,.example{break-inside:avoid}}

/* ---------- 全局标识(谭老师的数学课) ---------- */
.kc-home{display:flex;align-items:center;gap:10px;margin:-6px -8px 22px;padding:8px;border-radius:10px;color:var(--ink)}
.kc-home:hover{background:var(--soft);text-decoration:none}
.kc-home .tlogo{width:36px;height:36px;flex:0 0 36px}
.kc-home b{display:block;font-size:15px;letter-spacing:.08em;line-height:1.3}
.kc-home small{display:block;font:10px var(--mono);letter-spacing:.12em;color:var(--muted)}
@media print{.kc-home{display:none}}

/* ---------- 全屏 + 批注套件(默认收起) ---------- */
#kc-ink-base,#kc-ink-live{position:fixed;inset:0;pointer-events:none;z-index:40}
body.kc-drawing #kc-ink-live{pointer-events:auto;touch-action:none;cursor:crosshair}
#kc-dock{position:fixed;right:18px;bottom:18px;z-index:45;display:flex;align-items:center;gap:8px}
.kc-fab{display:flex;align-items:center;gap:6px;height:40px;min-width:40px;justify-content:center;padding:0 12px;border-radius:20px;background:#fffffff2;border:1px solid #cadbd5;color:var(--teal);box-shadow:0 4px 14px #17343c1f;font-size:13px}
.kc-fab:hover{background:#eef7f2}.kc-fab.on{background:var(--teal);color:#fff;border-color:var(--teal)}
.kc-fab[data-act=fs]{padding:0;width:40px}
.kc-tools{display:flex;align-items:center;gap:4px;background:#fffffff7;border:1px solid #cadbd5;border-radius:14px;padding:5px 7px;box-shadow:0 6px 20px #17343c24}
.kc-tools[hidden]{display:none}
.kc-tools button{width:34px;height:34px;padding:0;border-radius:9px;border:1px solid transparent;background:transparent;color:var(--ink);font-size:16px;line-height:1}
.kc-tools button:hover{background:var(--soft)}.kc-tools button.on{background:#e1f2ef;border-color:#9cc9bf;color:#176b60}
.kc-tools .sw::before{content:"";display:block;width:16px;height:16px;margin:auto;border-radius:50%;background:var(--c)}
.kc-tools .sw.on{background:#fff;border-color:var(--c)}
.kc-tools i{width:1px;height:22px;background:var(--line);margin:0 3px}
@media (max-width:980px){#kc-dock{right:10px;bottom:10px;flex-wrap:wrap-reverse;justify-content:flex-end;max-width:calc(100vw - 20px)}.kc-tools{flex-wrap:wrap}.kc-fab span{display:none}}
@media print{#kc-dock,#kc-ink-live{display:none!important}}

/* ---------- 打印:不打印浏览器页眉页脚(文件地址、日期、页码) ----------
   Chrome:第一页的页边距里放不下页眉页脚时,后面各页也不再打印(developer.chrome.com/blog/print-margins)。
   所以第一页上下边距为 0、留白由 body 提供,其余页保留正常页边距。Safari / Firefox 需在打印对话框里取消"页眉和页脚"。 */
@page{size:A4;margin:14mm 13mm}
@page:first{margin:0 13mm}
@media print{html,body{background:#fff}body{padding-top:14mm}#kc-progress,#kc-lightbox{display:none!important}main.kc-main .principles article,main.kc-main .timeline li,main.kc-main .goals li,main.kc-main .compare>div{break-inside:avoid}}