:root{--paper:#f1eee6;--ink:#2e352f;--muted:#777a6e;--red:#943f30;--line:#d9d8cb;--green:#465f50;--gold:#b38b48;--serif:"Songti SC","Noto Serif CJK SC","SimSun",serif;--sans:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",sans-serif}
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#18251540}.sources-dialog::backdrop{background:#293c3255;backdrop-filter:blur(4px)}.dialog-head{display:flex;justify-content:space-between;align-items:center;padding:30px 35px 22px;border-bottom:1px solid var(--line)}.dialog-head h2{font:30px var(--serif);font-weight:500;margin:12px 0 0}.close-dialog{font-size:30px;padding:5px 8px}.dialog-body{padding:15px 35px 30px;line-height:1.9;font-size:12px;color:#687060}.dialog-body h3{font:20px var(--serif);color:var(--ink);margin-top:26px}.dialog-body a{color:var(--red);text-underline-offset:4px}.note-grid{display:grid;grid-template-columns:1fr 1fr;gap:16px}.note-grid>div{border:1px solid var(--line);padding:17px}.note-grid strong{display:block;color:var(--green);margin-bottom:6px}.source-list{padding-left:20px}.source-list li{margin:14px 0}.source-list small{display:block;color:#929586}.assembly-panel{position:absolute;bottom:25px;left:36px;right:36px;display:flex;align-items:center;gap:12px;background:#faf7eedb;border:1px solid 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@media(min-width:1650px){.intro{left:60px;top:75px}.story-card{right:60px;top:150px;width:295px}.viewer{left:240px;right:320px}.view-tools{left:60px}.explore-dock{left:60px;right:60px}.story-card p{font-size:13px}.story-card h2{font-size:30px}h1{font-size:80px}}
@media(max-width:1150px){.site-header{margin:0 24px}.brand-sub{display:none}.mode-tabs{gap:22px}.source-trigger{font-size:10px}.intro{left:26px;width:190px;top:35px}h1{font-size:55px;letter-spacing:5px}h1 span{font-size:16px;letter-spacing:2px}.intro-copy{font-size:11px}.facts{gap:20px}.viewer{left:180px;right:225px}.story-card{right:24px;width:225px;top:115px;padding:20px 18px}.story-card h2{font-size:23px}.story-card p{font-size:11px}.story-card .mini-diagram{height:62px}.view-tools{left:26px}.explore-dock{left:24px;right:24px;gap:20px;padding:20px}.dock-heading{gap:10px}.dock-heading strong{font-size:15px}.dock-heading small{font-size:9px}.dock-icon{display:none}.stage-labels button{font-size:9px}.footer-index{display:none}}
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@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}
/* Small screens keep the lesson and controls in normal flow, so longer explanations never overlap. */
@media(max-width:800px){#experience{padding-top:612px;min-height:0}.facts{top:28px;margin-top:0}.story-card{position:relative;left:auto;right:auto;top:auto;margin:0 22px;min-height:0}.explore-dock{margin:20px 22px 22px}.assembly-panel{margin:20px 22px 22px}.story-card p{font-size:12px}.story-card h2{font-size:24px}.stage-labels button{font-size:9px}.interaction-hint{top:579px}}
@media(min-width:801px) and (max-height:820px){.story-card{top:58px;padding:17px 19px}.card-overline{margin-top:17px}.story-card h2{font-size:24px;margin-bottom:10px}.story-card p{font-size:11px;line-height:1.8}.mini-diagram{height:48px;margin:8px 0 12px;padding-bottom:8px}.simplified{font-size:8px!important;padding-top:9px}.card-next{margin-top:10px;padding-top:10px}.intro{top:35px}}