@charset "UTF-8";
:root{--paper:#f6f5ef;--ink:#163d43;--muted:#657b7b;--teal:#168879;--coral:#d85b42;--line:#d9e1d9;--blue:#4b79b5;--white:#fffef9;font-family:Inter,"Noto Sans SC","PingFang SC","Microsoft YaHei",sans-serif;color:var(--ink);background:var(--paper);font-synthesis:none}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:32px}body{margin:0}a{color:inherit;text-decoration:none}button,input,select{font:inherit}button,a,input,select,summary{-webkit-tap-highlight-color:transparent}button{cursor:pointer}button:focus-visible,a:focus-visible,input:focus-visible,summary:focus-visible,select:focus-visible{outline:3px solid #df9d39;outline-offset:5px}button{color:inherit}p{line-height:1.85}main,.masthead,footer{max-width:1200px;margin:0 auto;padding-left:40px;padding-right:40px}.masthead{height:100px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line)}.brand{display:inline-flex;align-items:center;gap:10px;font-weight:700;font-size:19px;letter-spacing:1px}.brand-mark{font-size:39px;line-height:.6;color:var(--teal)}.brand-en{font-size:10px;letter-spacing:2px;margin-left:12px;color:var(--muted)}nav{display:flex;gap:30px;font-size:13px}nav a:hover,.text-link:hover{color:var(--teal)}.intro{padding:65px 0 40px}.eyebrow{font-size:11px;font-weight:600;letter-spacing:2px;display:block;color:var(--muted)}.intro .eyebrow{display:flex;align-items:center;gap:9px}.eyebrow>span{height:7px;width:7px;background:var(--teal);border-radius:50%}h1{font-size:clamp(45px,6.8vw,78px);line-height:1.25;letter-spacing:-3px;font-weight:650;margin:24px 0}h1>span{color:var(--teal)}.intro-bottom{display:flex;justify-content:space-between;align-items:end;gap:30px}.intro p{margin:0;font-size:15px;color:var(--muted)}.text-link{border-bottom:1px solid var(--ink);padding:12px 0;font-size:14px;white-space:nowrap;display:flex;gap:42px}.text-link span{font-size:23px}.motion-panel{background:#103d44;border-radius:6px;color:#edf7ee;overflow:hidden;padding:28px 32px 18px;position:relative}.panel-top{display:flex;justify-content:space-between;align-items:center}.light{color:#90b7b4}.panel-top h2{font-size:24px;margin:10px 0 0;font-weight:500}.chip{border:1px solid #487075;border-radius:20px;padding:8px 12px;font-size:11px;color:#b7d1cd}.motion-panel canvas{width:100%;display:block;height:auto}.motion-footer{display:flex;justify-content:space-between;align-items:center;gap:20px}.motion-footer p{font-size:13px;color:#c0d6d2;max-width:490px;margin:8px 0}.segmented{display:flex;flex-shrink:0;border-radius:5px;padding:4px;gap:3px}.dark{background:#092f36}.segmented button{border:0;background:transparent;color:#b5cdca;padding:10px 13px;border-radius:3px;font-size:12px}.dark button.active{background:#e2eee5;color:#153c43}.motion-note{color:#91b4b1;font-size:11px;margin:12px 0 0}.bridge{padding:68px 0;max-width:800px;margin:auto;text-align:center}.section-number{font-size:11px;letter-spacing:2px;color:var(--teal)}h2{font-weight:600;letter-spacing:-.8px;font-size:31px;line-height:1.5}.bridge h2{margin:16px 0}.bridge p{color:var(--muted);font-size:15px;margin:0}.bridge strong{color:var(--ink);font-weight:600}.section-heading{display:flex;align-items:end;justify-content:space-between;gap:20px;margin-bottom:26px}.section-heading h2{margin:12px 0 0}.subtle{font-size:11px;color:var(--muted)}.lab-grid{display:grid;grid-template-columns:1.45fr 1fr;border:1px solid var(--line);background:var(--white);border-radius:6px;overflow:hidden}.diagram-card{padding:23px 26px;background:#edf2e9;border-right:1px solid var(--line);min-width:0}.diagram-top{display:flex;justify-content:space-between;font-size:12px;gap:15px}.diagram-top span:first-child{color:var(--teal);font-weight:600}.diagram-top span:last-child{color:var(--muted)}canvas{max-width:100%}#foil{width:100%;height:auto;display:block}.legend{display:flex;flex-wrap:wrap;gap:12px 18px;font-size:11px;justify-content:center;color:#4b6767}.legend span{display:flex;align-items:center;gap:5px}.legend i{display:inline-block;width:15px;height:3px}.teal{background:var(--teal)}.coral{background:var(--coral)}.blue{background:var(--blue)}.gray{background:#71847c}.transport{border-top:1px solid #d2ddcf;margin-top:25px;padding-top:20px;display:flex;align-items:center;justify-content:space-between;gap:12px}.play{background:var(--ink);color:white;border:0;border-radius:4px;font-size:13px;padding:11px 16px;min-width:85px}.speed{font-size:11px;display:flex;align-items:center;gap:8px;color:var(--muted)}select{border:1px solid #c6d3c3;background:transparent;color:var(--ink);padding:8px 6px;border-radius:3px;font-size:12px}.reset{font-size:12px;border:0;background:transparent;padding:9px}.phase-control{font-size:11px;color:var(--muted);display:block;margin-top:20px}.phase-control output{float:right;font-variant-numeric:tabular-nums}input[type=range]{accent-color:var(--teal);width:100%;margin:15px 0 0;cursor:pointer;height:22px}.controls{padding:32px}.controls h3{font-size:25px;line-height:1.6;font-weight:500;margin:13px 0 25px}.mode-buttons{display:grid;gap:8px}.mode-buttons button{border:1px solid var(--line);background:transparent;padding:13px 12px;text-align:left;font-size:12px;border-radius:4px;display:flex;align-items:center;gap:10px;min-height:44px}.mode-buttons button span{font-size:10px;color:var(--muted)}.mode-buttons button b{margin-left:auto;font-size:17px;font-weight:400}.mode-buttons .active{background:#e9f1e8;border-color:var(--teal);color:#11695f}.angle-control{display:block;margin-top:26px;font-size:12px}.angle-control output{float:right;color:var(--teal);font-size:16px;font-variant-numeric:tabular-nums}.small{font-size:11px;color:var(--muted);margin:8px 0 20px;line-height:1.7}.observation{border-left:2px solid var(--teal);padding-left:15px}.observation>span{font-size:10px;letter-spacing:2px;color:var(--teal)}.observation p{font-size:13px;min-height:74px;margin:8px 0 12px}.check{display:flex;align-items:center;gap:8px;color:var(--muted);font-size:12px}.check input{accent-color:var(--teal);width:15px;height:15px}.chart-strip{display:grid;grid-template-columns:1fr 1.45fr;align-items:center;gap:35px;padding:32px 25px;border-bottom:1px solid var(--line)}.chart-strip h3{font-size:21px;font-weight:500;margin:12px 0}.chart-strip p{font-size:11px;color:var(--muted);margin-bottom:0}.chart-wrap canvas{width:100%;display:block}.chart-wrap p{font-size:10px;text-align:center;margin:5px}.coral-text{color:var(--coral)}.teal-text{color:var(--teal)}details{border-bottom:1px solid var(--line)}summary{list-style:none;cursor:pointer;font-size:13px;padding:22px 0;display:flex;justify-content:space-between;gap:20px}summary::-webkit-details-marker{display:none}summary>span{font-size:18px;color:var(--teal)}details[open] summary>span{transform:rotate(45deg)}.model-details>div{padding:0 25px 22px;background:#eef1e8;border-radius:4px}.model-details p{font-size:13px;padding-top:16px;margin:0;color:var(--muted)}code{font-size:12px;color:var(--ink);overflow-wrap:anywhere}.reality{display:grid;grid-template-columns:.9fr 1.3fr;gap:80px;padding:90px 0;border-bottom:1px solid var(--line)}.reality h2{font-size:38px;line-height:1.4;margin:18px 0}.reality-intro p{font-size:14px;color:var(--muted)}.reasons article{display:flex;gap:22px;padding:0 0 23px;margin-bottom:23px;border-bottom:1px solid var(--line)}.reasons article:last-child{margin:0;padding:0;border:0}.reasons article>span{color:var(--teal);font-size:12px;padding-top:5px}.reasons h3{font-weight:500;font-size:18px;margin:0 0 9px}.reasons p{font-size:13px;color:var(--muted);margin:0}.comparison{padding:58px 0}.comparison h2{font-size:25px;margin:16px 0 28px}.compare-grid{display:grid;grid-template-columns:1fr 1fr;gap:40px}.compare-grid article{border-top:2px solid #a6c7b8;padding:22px 0 0}.compare-grid article:last-child{border-color:var(--teal)}.compare-grid article>span{font-size:11px;color:var(--teal)}.compare-grid h3{font-size:19px;font-weight:500;margin:12px 0}.compare-grid p{font-size:13px;color:var(--muted);margin:0}.practice{padding:50px 0 55px}.practice-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:30px}.practice-grid article{border-top:1px solid var(--line);padding-top:24px}.step{font-size:32px;font-family:Georgia,serif;font-style:italic;color:var(--teal)}.practice-grid h3{font-size:19px;font-weight:500;margin:18px 0 13px}.practice-grid p{font-size:13px;color:var(--muted)}.practice-grid strong{font-size:12px;font-weight:500;color:var(--ink);display:block;padding-top:8px;line-height:1.8}.practice-note{margin-top:30px;font-size:11px;color:var(--muted);background:#ecefe5;padding:15px 20px;border-radius:3px}.sources{padding:28px 0 50px;border-top:1px solid var(--line)}.sources p{font-size:12px;max-width:850px;color:var(--muted)}.sources>a{font-size:11px;color:var(--teal);display:block;margin:12px 0;line-height:1.7}.sources>a:hover{text-decoration:underline}footer{display:flex;justify-content:space-between;align-items:center;gap:25px;min-height:110px;border-top:1px solid var(--line);font-size:11px;color:var(--muted)}footer .brand{font-size:14px;color:var(--ink)}footer .brand-mark{font-size:30px}
@media(min-width:1600px){main,.masthead,footer{max-width:1360px}.intro{padding-top:85px}}
@media(max-width:900px){main,.masthead,footer{padding-left:25px;padding-right:25px}.motion-footer{flex-direction:column;align-items:start}.motion-footer p{max-width:none}.controls{padding:25px 20px}.controls h3{font-size:22px}.diagram-card{padding:20px 16px}.reality{gap:35px}.practice-grid{gap:20px}.speed{font-size:0}.speed select{font-size:12px}.transport{gap:4px}.chip{font-size:10px}}
@media(max-width:640px){main,.masthead,footer{padding-left:20px;padding-right:20px}.masthead{height:75px}.brand{font-size:17px}.brand-en{display:none}nav{gap:16px;font-size:11px}.intro{padding:40px 0 28px}h1{font-size:49px;letter-spacing:-2px}.intro-bottom{display:block}.intro p{font-size:13px}.desktop{display:none}.text-link{display:inline-flex;margin-top:15px;font-size:12px;gap:25px}.motion-panel{padding:20px 14px 15px;margin:0 -8px}.panel-top h2{font-size:20px}.panel-top{align-items:start}.chip{border:0;max-width:95px;text-align:right;padding:0;line-height:1.7;font-size:10px}.eyebrow{font-size:9px;letter-spacing:1.5px}.motion-panel canvas{margin:12px -8px;width:calc(100% + 16px);max-width:none}.motion-footer{gap:9px}.motion-footer p{font-size:11px;line-height:1.8;min-height:40px;margin:0}.segmented{width:100%}.segmented button{flex:1;padding:10px 6px}.motion-note{font-size:9px;line-height:1.7}.bridge{padding:45px 0;text-align:left}.bridge h2{font-size:27px}.bridge p{font-size:13px}.section-heading{align-items:start;flex-direction:column;gap:9px;margin-bottom:18px}.section-heading h2{font-size:27px;margin:10px 0 0}.lab-grid{grid-template-columns:1fr}.diagram-card{border-right:0;border-bottom:1px solid var(--line);padding:20px 15px}.diagram-top{font-size:10px}.legend{font-size:10px;gap:11px}.transport{margin-top:20px}.speed{font-size:11px}.controls{padding:25px 20px}.controls h3 br{display:none}.controls h3{font-size:22px;margin:10px 0 20px}.mode-buttons button{font-size:13px;padding:14px}.observation p{min-height:0}.chart-strip{grid-template-columns:1fr;padding:25px 0;gap:16px}.chart-strip h3{margin:10px 0}.chart-strip p br{display:none}summary{font-size:12px;line-height:1.7}.model-details>div{padding:0 15px 20px}.model-details p{font-size:12px}.reality{grid-template-columns:1fr;padding:55px 0;gap:26px}.reality h2{font-size:32px}.reality h2 br{display:none}.reality-intro p{font-size:13px}.reasons h3{font-size:17px}.reasons article{gap:15px}.comparison{padding:40px 0 20px}.comparison h2{font-size:23px}.compare-grid{gap:25px;grid-template-columns:1fr}.practice{padding:40px 0 35px}.practice-grid{grid-template-columns:1fr;gap:25px}.practice-grid article{position:relative;padding:20px 0 0 44px}.practice-grid .step{position:absolute;left:0;top:28px}.practice-grid h3{margin-top:8px}.practice-grid strong{padding:0}.practice-note{padding:15px;font-size:10px}.sources{padding-bottom:30px}footer{flex-wrap:wrap;min-height:125px;gap:12px;padding-top:22px;padding-bottom:22px}footer>span{width:100%;order:3;font-size:10px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
.diagram-explanation{font-size:11px;line-height:1.7;color:var(--muted);margin:0 0 16px;text-align:center}