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@media(max-height:760px),(max-width:899px) and (max-height:900px){.js .scroll-story.is-pinned{min-height:0}.js .scroll-story.is-pinned .stage{position:relative;top:auto;height:auto;min-height:0;padding:0;display:block}.stage .scene-wrap{height:430px}}
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.label-load{left:50%;transform:translateX(-50%);top:3%;bottom:auto;width:190px;text-align:center}@media(max-width:600px){.label-load,[data-anchor="load"],[data-dot="load"]{display:none}.process-visual{height:290px}}.family-static+.family-static{margin-top:42px}.family-static p{margin-top:14px;color:var(--muted)}

/* The vector reading path follows the same load/release envelope without WebGL. */
[data-scene="compression"] .poster{transform-origin:50% 75%}

.static-study{margin-top:80px}

/* Material-first navigation and visual lessons. */
.topbar{height:auto;min-height:64px;display:grid;grid-template-columns:auto 1fr auto;gap:20px}
.material-nav{display:flex;justify-content:center;align-items:center;gap:clamp(12px,2.5vw,38px)}
.material-nav a{display:flex;align-items:center;justify-content:center;min-height:54px;min-width:44px;font-size:13px;letter-spacing:.015em;text-decoration:none;color:var(--muted)}
.material-nav a[aria-current=true]{color:var(--accent);text-decoration:underline;text-underline-offset:7px}
.js .family-chooser{display:block}.family-tabs{display:grid;grid-template-columns:repeat(5,1fr);gap:0;border-bottom:1px solid var(--line);margin-bottom:36px;overflow:visible;padding:0}
.family-tab{justify-content:center;border:0;font-size:24px;min-height:62px;padding:10px 2px}.family-tab:after{display:none}.family-tab[aria-selected=true]{box-shadow:0 2px 0 var(--accent)}
.analogy-grid{display:grid;grid-template-columns:1.3fr 1fr;gap:clamp(32px,5vw,72px);align-items:center}
.ball-canvas{position:relative;background:#f6f6f4;aspect-ratio:760/520;overflow:hidden}.ball-canvas svg{width:100%;height:100%}.ball-phase{position:absolute;left:18px;bottom:15px;font-size:12px;color:var(--muted)}
.analogy-copy h3{font-family:var(--serif);font-size:clamp(32px,3.4vw,46px);font-weight:400;letter-spacing:-.045em;line-height:1.06}.ball-borrow{font-size:18px;margin-top:16px;color:var(--muted);max-width:24ch}
.analogy-bridge{margin-top:28px}.analogy-bridge>span{display:block;font-size:24px;color:var(--accent);margin-bottom:14px}.analogy-bridge h4{font-size:16px;font-weight:600;line-height:1.4;margin:0 0 9px}.analogy-bridge>p{font-size:15px;color:var(--muted);line-height:1.55}
.analogy-copy .family-title{margin-bottom:20px;font-size:12px}.molecular-detail{margin-top:10px}.molecular-detail .molecule{height:132px;transform-origin:center;will-change:transform}.molecule-legend{font-size:12px;gap:12px;justify-content:flex-start;flex-wrap:wrap}.analogy-note{margin-top:28px;max-width:none}
.lesson-controls{display:grid;grid-template-columns:110px 1fr 58px;align-items:center;gap:16px;margin-top:16px;font-size:12px;color:var(--muted)}.lesson-controls label{line-height:1.35}.lesson-controls button{text-align:right}
.lesson-mode{display:flex;gap:30px;border-bottom:1px solid var(--line);margin-bottom:30px}.lesson-mode button{min-height:54px;padding:0 0 12px;font-size:15px;color:var(--muted)}.lesson-mode button[aria-pressed=true]{box-shadow:0 2px 0 var(--accent);color:var(--ink)}
.energy-pair{display:grid;grid-template-columns:1fr 1fr;gap:60px;max-width:900px;margin:auto}.energy-specimen svg{width:100%;max-height:350px}.energy-specimen figcaption{text-align:center;font-size:16px;color:var(--muted)}.energy-lab>.lesson-controls{max-width:740px;margin:40px auto 0}.energy-conclusion{text-align:center;font-family:var(--serif);font-size:clamp(25px,3vw,38px);line-height:1.2;letter-spacing:-.03em;margin-top:32px}
.js .lesson-controls{display:grid}.js .lesson-mode{display:flex}
@media(max-width:899px){.analogy-grid{grid-template-columns:1fr;gap:38px}.ball-canvas{max-height:480px}.analogy-copy{display:grid;grid-template-columns:1fr 1fr;gap:0 32px;align-items:start}.analogy-copy>.family-title{grid-column:1}.analogy-copy>h3,.analogy-copy>.ball-borrow{grid-column:1}.analogy-bridge{grid-column:2;grid-row:1/5;margin:0}.analogy-bridge>span{display:none}.ball-borrow{font-size:17px}.family-tabs{grid-template-columns:repeat(5,1fr)}.family-tab{font-size:23px}.energy-pair{gap:20px}}
@media(max-width:600px){.topbar{grid-template-columns:1fr auto;gap:0 20px;padding:0 20px;min-height:100px}.topbar>.brand{min-height:48px;display:flex;align-items:center}.material-nav{grid-column:1/-1;grid-row:2;justify-content:space-between;gap:0;border-top:1px solid #f0f2f2}.material-nav a{font-size:12px;min-height:44px}.contents{grid-column:2;grid-row:1}.contents nav{top:45px}.family-tabs{margin-bottom:22px}.family-tab{min-height:54px;font-size:20px}.analogy-grid{gap:28px}.analogy-copy{display:block}.analogy-copy h3{font-size:36px}.analogy-bridge{margin-top:26px}.analogy-bridge>span{display:block}.molecular-detail .molecule{height:145px}.lesson-controls{grid-template-columns:1fr 56px;gap:0 14px}.lesson-controls label{grid-column:1/-1}.energy-pair{gap:8px}.energy-specimen figcaption{font-size:13px}.energy-lab>.lesson-controls{margin-top:28px}.lesson-mode{gap:24px}.lesson-mode button{font-size:14px}.energy-conclusion{font-size:28px}.ball-phase{font-size:12px;bottom:10px;left:12px}}

.family-static{display:grid;grid-template-columns:180px 1fr;gap:32px;align-items:center}.family-static svg{width:100%;height:auto}@media(max-width:600px){.family-static{grid-template-columns:1fr;gap:8px}.family-static svg{width:200px;max-width:100%}}

.family-tab{white-space:nowrap}@media(max-width:600px){.ball-canvas svg{transform:scale(1.2)}}@media(max-width:360px){.family-tab{font-size:18px;letter-spacing:-.03em}}

/* The shifted spine needs room for its full hit area and focus ring. Contents stays available below this width. */
@media(max-width:1311px){.spine{display:none}}

/* Balance short decks independently of the long-form research prose. */
p{ text-wrap:pretty }
.hero .dek,.chapter-head .dek p,.intro .lead,.takeaway{ text-wrap:balance }
/* hero: foam, baked (bake-hero.js) — the live step label and the replay control */
.hero-actions{display:flex;gap:24px}
.hero-foot .bake-step{margin-left:auto;font:500 11px/1.4 ui-monospace,SFMono-Regular,Menlo,monospace;letter-spacing:.08em;text-transform:uppercase;color:#aab8bd;max-width:none}
@media(max-width:899px){.hero-foot{flex-wrap:wrap;row-gap:4px}.hero-foot .bake-step{order:-1;flex-basis:100%;margin-left:0}}