:root,:root[data-theme=light]{color-scheme:light;--page: #ffffff;--surface: #ffffff;--ink: #18181b;--secondary: #5f6368;--quiet: #71717a;--border: #e4e4e7;--accent: #3f3f46;--tint: #f4f4f5}:root[data-theme=dark]{color-scheme:dark;--page: #0f0f10;--surface: #171719;--ink: #f4f4f5;--secondary: #a1a1aa;--quiet: #a1a1aa;--border: #303033;--accent: #d4d4d8;--tint: #242427}.encyclopedia-nav{display:flex;gap:24px;align-items:center;min-height:64px;padding:12px 36px;color:var(--ink);background:var(--page);border-bottom:1px solid var(--border);font:13px/1.5 Inter,PingFang SC,sans-serif}.encyclopedia-nav a{color:inherit;text-decoration:none}.encyclopedia-nav a:hover{text-decoration:underline;text-underline-offset:5px}.encyclopedia-home{font-weight:600;white-space:nowrap}.encyclopedia-trail{display:flex;gap:12px;color:var(--secondary);flex:1}.theme-control{display:flex;align-items:center;gap:9px;color:var(--secondary);white-space:nowrap;font-size:12px}.theme-control select{font:inherit;color:var(--ink);background:var(--surface);border:1px solid var(--border);border-radius:8px;padding:8px 25px 8px 10px;cursor:pointer}.theme-control select:focus-visible,.encyclopedia-nav a:focus-visible{outline:2px solid var(--accent);outline-offset:4px}@media(max-width:700px){.encyclopedia-nav{padding:12px 18px;gap:12px;flex-wrap:wrap}.encyclopedia-trail{order:3;flex-basis:100%;font-size:11px}.encyclopedia-preferences{margin-left:auto}.encyclopedia-preferences .theme-control>span{display:none}}.encyclopedia-preferences,#catalog-appearance{display:flex;align-items:center;flex-wrap:wrap;gap:12px}:root{--ui-font: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif}html body{font-family:var(--ui-font);-webkit-font-smoothing:antialiased}.encyclopedia-nav{min-height:68px;padding:14px max(16px,calc((100% - 1120px)/2));gap:24px;font-family:var(--ui-font)}.encyclopedia-home{font-size:16px;font-weight:650;letter-spacing:-.02em}.encyclopedia-trail{font-size:12px;min-width:0;flex-wrap:wrap;gap:8px}.theme-control select{border-radius:6px;min-height:36px}html[data-topic-ui] body{background:var(--page);color:var(--ink)}html[data-topic-ui] main{max-width:1200px}html[data-topic-ui] .hero h1{font-size:clamp(30px,3.6vw,46px);line-height:1.2;font-weight:700;letter-spacing:-.035em}html[data-topic-ui] :is(.explorer,.observation,.formula-card){border-radius:8px}html[data-topic-ui] :is(.controls,.modes,.steps,.toolbar,.settings,.leaf-types,.season-controls) button,html[data-topic-ui] :is(.controls,.settings) select{border-radius:6px}html[data-topic-ui] .hero .intro{line-height:1.8}html[data-topic-ui] :is(.modes,.reading-mode) button[aria-pressed=true]{background:var(--accent);color:var(--page);border-color:var(--accent)}html[data-topic-ui] .reading-mode{background:var(--tint);border-color:var(--border);border-radius:8px}html[data-topic-ui] .reading-mode button{border-radius:6px}@media(max-width:700px){.encyclopedia-nav{padding:12px 16px;gap:12px}.encyclopedia-trail{font-size:11px}}html[data-topic-ui] .page-header .mode-switch{border-color:var(--border);border-radius:8px;background:var(--tint)}html[data-topic-ui] .page-header .mode-switch button{border-radius:6px;color:var(--secondary)}html[data-topic-ui] .page-header .mode-switch button[aria-pressed=true]{background:var(--accent);color:var(--page)}html[data-topic-ui] .hero h1 span{color:inherit}html[data-topic-ui] .season-controls .primary,html[data-topic-ui] #journey[aria-pressed=true]{background:var(--accent);color:var(--page);border-color:var(--accent)}@media(prefers-reduced-motion:no-preference){html[data-topic-ui] :is(.controls,.modes,.steps,.toolbar,.settings,.leaf-types,.season-controls,.mode-switch) button{transition:background-color .18s ease,color .18s ease,border-color .18s ease,box-shadow .18s ease}}html[data-topic-ui] :is(.controls,.settings) :is(input,select,button):focus-visible{outline:2px solid var(--ink);outline-offset:4px}:root{font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;color:var(--ink);background:var(--page);--topic-accent:#80535f}*{box-sizing:border-box}body{margin:0}main{width:min(1180px,calc(100% - 48px));margin:auto;padding:54px 0 58px}.hero{max-width:820px;margin-bottom:30px}.eyebrow{font-size:11px;letter-spacing:.12em;font-weight:650;color:var(--secondary);margin:0 0 14px}h1{font-size:clamp(34px,4.9vw,58px);font-weight:650;line-height:1.2;letter-spacing:-.045em;margin:0 0 22px}.intro{font-size:18px;line-height:1.85;color:var(--secondary);max-width:800px;margin:0}button,input{font:inherit}button{cursor:pointer}button:focus-visible,a:focus-visible,summary:focus-visible,input:focus-visible{outline:2px solid var(--ink);outline-offset:4px}button:disabled{opacity:.5;cursor:default}.laboratory{border:1px solid var(--border);border-radius:21px;background:var(--surface);overflow:hidden;box-shadow:0 15px 35px #4a282809}.experiment-tabs{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:6px;padding:14px;border-bottom:1px solid var(--border)}.experiment-tabs button{display:flex;gap:12px;align-items:center;justify-content:center;padding:17px 8px;border:1px solid transparent;border-radius:10px;background:transparent;color:var(--secondary);font-size:15px;font-weight:550}.experiment-tabs button[aria-pressed=true]{background:var(--tint);border-color:var(--border);color:var(--ink)}.tab-number{font-size:11px;opacity:.7;font-variant-numeric:tabular-nums}.scene-wrap{background:#efe5dc;color:#594653;padding:20px 22px 0}.scene-heading{display:flex;justify-content:space-between;gap:14px;align-items:baseline;padding:0 8px 12px;font-size:14px;font-weight:600}.model-note{font-size:10px;font-weight:400;text-align:right;color:#75645e}#scene{display:block;width:100%;max-height:620px;overflow:hidden;font-family:inherit}.playbar{display:flex;align-items:center;gap:10px;padding:20px 24px;border-top:1px solid var(--border);flex-wrap:wrap}.playbar button{min-height:43px;border:1px solid var(--border);background:var(--surface);color:var(--ink);border-radius:8px;padding:10px 17px;font-size:13px}.playbar #play{background:var(--ink);color:var(--surface)}.timeline{flex:1;min-width:170px;padding:0 10px;font-size:11px;color:var(--secondary);display:flex;align-items:center;gap:18px}.timeline input{flex:1;min-width:70px;accent-color:var(--topic-accent);cursor:pointer}output{color:var(--secondary);width:42px;font-size:12px;font-variant-numeric:tabular-nums}.steps{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px;padding:0 24px 22px}.steps button{min-height:46px;padding:9px 13px;border:1px solid var(--border);border-radius:9px;color:var(--secondary);background:var(--page);text-align:left;font-size:12px;line-height:1.5}.steps button[aria-pressed=true]{border-color:var(--secondary);color:var(--ink)}.readout{display:grid;grid-template-columns:1.1fr 1fr;gap:36px;padding:26px 30px;background:var(--tint);border-top:1px solid var(--border)}.readout h2{font-size:22px;line-height:1.5;letter-spacing:-.025em;margin:0 0 10px}.readout .eyebrow{margin-bottom:8px}.readout p:not(.eyebrow){font-size:14px;line-height:1.9;margin:0;color:var(--secondary)}#observe{border-left:1px solid var(--border);padding-left:28px;align-self:center}.discoveries{display:grid;grid-template-columns:repeat(3,1fr);gap:34px;padding:40px 9px}.number{font-size:11px;color:var(--secondary);letter-spacing:.09em}.discoveries h2{font-size:20px;line-height:1.6;margin:12px 0 10px;letter-spacing:-.025em}.discoveries p,.science p,.science li{font-size:14px;line-height:1.95;color:var(--secondary);margin:0}.science{border-top:1px solid var(--border);border-bottom:1px solid var(--border);padding:20px 0}.science summary{cursor:pointer;font-size:14px;font-weight:600}.science p{padding:20px 0 5px;max-width:950px}.science a{color:var(--secondary);text-underline-offset:4px;overflow-wrap:anywhere}.related{display:flex;gap:20px;padding-top:28px;font-size:13px}.related a{color:var(--secondary);text-underline-offset:5px}@media(max-width:700px){main{width:calc(100% - 28px);padding-top:36px}.hero{margin-bottom:24px}.intro{font-size:16px}h1{font-size:35px}.experiment-tabs{padding:8px;gap:2px}.experiment-tabs button{flex-direction:column;gap:6px;padding:11px 3px;font-size:12px}.scene-wrap{padding:17px 0 0}.scene-heading{padding:0 14px 13px;font-size:12px;align-items:start}.model-note{max-width:155px;line-height:1.5;font-size:9px}.playbar{padding:16px 15px;gap:8px}.playbar button{padding:9px 14px}.timeline{order:3;flex-basis:calc(100% - 48px);padding:4px 0}.playbar output{order:4}.steps{padding:0 14px 16px;gap:5px}.steps button{font-size:11px;padding:8px;line-height:1.6}.readout{grid-template-columns:1fr;padding:22px;gap:18px}.readout h2{font-size:21px}#observe{border-left:0;border-top:1px solid var(--border);padding:17px 0 0}.discoveries{grid-template-columns:1fr;gap:25px;padding:32px 6px}.discoveries h2{font-size:20px;margin-top:8px}.laboratory{border-radius:15px}}@media(prefers-reduced-motion:no-preference){button{transition:background-color .16s,border-color .16s,color .16s}}#scene{aspect-ratio:980/550}.zoom-control{display:block;margin:10px auto 0;position:relative;transform:translateY(-8px);border:1px solid #aa978860;border-radius:7px;background:#fffaf0d9;color:#594f46;min-height:36px;padding:7px 14px;font-size:12px}.zoom-control[aria-pressed=true]{background:#e8ddcb}