:root{--ink:#183849;--muted:#607b89;--blue:#376d88;--line:#d5e1e6;--paper:#fff;--wash:#f0f6f8;--accent:#bc601f}*{box-sizing:border-box}body{margin:0;color:var(--ink);background:var(--paper);font-family:"Microsoft YaHei","PingFang SC",sans-serif;font-size:15px;line-height:1.55}#module{max-width:1160px;margin:auto;padding:20px}header{display:flex;justify-content:space-between;gap:24px;align-items:end;padding:0 0 16px}.eyebrow{margin:0;color:var(--blue);font-weight:700;letter-spacing:.12em;font-size:12px}h1{font-family:"SimSun","Songti SC",serif;font-size:28px;letter-spacing:.03em;margin:4px 0 0}p{margin:0}.intro{color:var(--muted);font-size:14px;max-width:21em}nav{display:flex;flex-wrap:wrap;gap:5px 8px;padding:12px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}nav a{color:var(--muted);text-decoration:none;padding:7px 12px;border-radius:5px;font-size:14px;font-weight:700}nav a[aria-current=true]{background:var(--blue);color:#fff}nav a:hover{background:var(--wash);color:var(--ink)}nav a[aria-current=true]:hover{background:var(--blue);color:#fff}a:focus-visible,summary:focus-visible{outline:3px solid var(--accent);outline-offset:3px}.panel-heading{display:flex;gap:20px;align-items:start;margin:18px 0 14px}.panel-heading h2{font-family:"SimSun","Songti SC",serif;margin:0;min-width:8.5em;font-size:20px;line-height:1.5}.panel-heading p{font-size:13px;line-height:1.65;max-width:68em;color:var(--muted)}.cards{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px 18px}.bridge-card{min-width:0;background:var(--paper);border-bottom:1px solid var(--line);padding-bottom:12px}.picture{display:block;aspect-ratio:400/230;position:relative;background:var(--wash);overflow:hidden;border-radius:5px;text-decoration:none}.picture img{display:block;width:100%;height:100%;object-fit:cover}.kind{position:absolute;left:8px;bottom:8px;background:#ffffffed;color:#294e60;border-radius:3px;padding:2px 6px;font-size:10px}.card-copy{padding-top:9px}.card-copy h3{font-size:18px;line-height:1.35;margin:0 0 3px}.card-copy p{font-size:13px}.card-copy .example{color:var(--blue);font-weight:600;margin-bottom:5px;font-size:12px}.source{margin-top:5px;font-size:11px;color:var(--muted)}summary{cursor:pointer;width:fit-content}a{color:var(--blue);text-underline-offset:3px}.source p{font-size:11px;margin-top:5px;overflow-wrap:anywhere}.secondary{margin-top:16px;padding:11px 13px;background:var(--wash);border-radius:5px;font-size:13px}.secondary>summary{font-weight:700}.secondary>p{margin:9px 0 14px}.secondary .cards{grid-template-columns:repeat(2,minmax(0,1fr));max-width:760px}.secondary .bridge-card{padding:8px}.reference{font-size:12px;margin-top:12px}footer{font-size:11px;color:var(--muted);margin-top:16px}section[hidden]{display:none}@media(min-width:1200px){#module{padding:25px}}@media(max-width:680px){#module{padding:13px}header{display:block;padding-bottom:12px}h1{font-size:25px}.intro{max-width:none;margin-top:7px;font-size:12px}nav{gap:4px;padding:8px 0}nav a{padding:6px 8px;font-size:12px}.panel-heading{display:block;margin:14px 0 12px}.panel-heading h2{font-size:19px}.panel-heading p{font-size:12px;margin-top:5px}.cards{grid-template-columns:repeat(2,minmax(0,1fr));gap:15px 12px}.card-copy h3{font-size:16px}.card-copy .example{font-size:11px}.card-copy p{font-size:12px}.kind{font-size:9px;left:5px;bottom:5px;padding:1px 4px}.secondary .cards{grid-template-columns:1fr}.source{font-size:10px}.source p{font-size:10px}}@media(max-width:340px){.cards{grid-template-columns:1fr}}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}}@media print{nav{display:none}section[hidden]{display:block}.classification-panel{break-before:page}.picture{break-inside:avoid}.source{display:none}}
.picture{cursor:zoom-in}.picture img{object-fit:contain}.cards:has(>article:nth-child(2):last-child){grid-template-columns:repeat(2,minmax(0,1fr))}.scale-options{display:flex;gap:8px;flex-wrap:wrap;margin:16px 0}.scale-options button{font:inherit;padding:9px 15px;border:1px solid #c5d6dc;border-radius:7px;background:#fff;color:#274958;cursor:pointer}.scale-options button[aria-pressed=true]{background:#346b81;color:#fff}#scale-view{width:100%;display:block;border:1px solid #d5e4e2;border-radius:8px}#scale-result{margin:15px 0;line-height:1.8}#scale-result strong{display:inline-block;background:#e4f1eb;color:#275e48;padding:3px 15px;border-radius:5px;margin-right:10px}#scale-result em{display:block;font-style:normal;color:#765129;font-size:13px}dialog{border:1px solid #c6d4d8;border-radius:10px;padding:15px;max-width:94vw;max-height:94vh;background:#fff;color:#214759}dialog::backdrop{background:#102531b8}dialog img{display:block;max-width:88vw;max-height:77vh;object-fit:contain}dialog button{display:block;margin-left:auto;margin-bottom:10px;font:inherit;padding:6px 14px;border:1px solid #a8c0ca;border-radius:4px;background:#fff;color:#214759}dialog p{font-size:13px;margin-top:10px}@media(max-width:600px){.cards,.cards:has(>article:nth-child(2):last-child){grid-template-columns:1fr}.picture{aspect-ratio:16/10}.scale-options button{padding:7px 10px;font-size:13px}.scale-lesson #scale-view{min-height:175px}#scale-result span{display:block;font-size:13px}.panel-heading p{font-size:13px}}
@media(max-width:600px){#scale-view text{font-size:30px}#scale-view text:first-of-type,#scale-view text:last-of-type{display:none}}
.relation-diagram{display:block;margin:10px 0;cursor:zoom-in}.relation-diagram img{width:100%;display:block;border:1px solid #d8e5e1;border-radius:6px}