/* Crimson Archive — The Physics Archive / Lesson System 001.
   Site-wide typography, navigation, and theme variables come from styles.css. */
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/* Collection landing: cinematic introduction and featured work. */
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/* Homepage component shared with The Physics Archive. */
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/* Archive 001 — cinematic story introduction and chapter guide. */
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/* Video stage, time dilation, and schematic clocks. */
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.math-display .katex-display{margin:0;overflow-x:auto;overflow-y:hidden;padding:4px 0}
.clock-comparison{padding:33px;background:#211a24;color:#f3eee6;border:1px solid #5b414d;box-shadow:18px 18px 0 -1px var(--surface),18px 18px 0 var(--line)}
.clock-topline{display:flex;justify-content:space-between;gap:15px;color:#c3a4ad;font:9px var(--font-mono);letter-spacing:.06em;border-bottom:1px solid #594552;padding-bottom:18px}
.clock-topline>span{color:#d8a67a}
.clock-row{display:flex;align-items:center;gap:20px;padding:28px 0;border-bottom:1px solid #4f3b48}
.clock-icon{display:grid;place-items:center;flex:0 0 65px;height:65px;border:1px solid #8a6572;border-radius:50%;font:22px var(--font-display);color:#d4b1c2}
.moving-clock{border-color:#b67b68;color:#e5c396}
.clock-row>div{flex:1;min-width:0}.clock-row small{display:block;font:9px var(--font-mono);color:#a99aa4;letter-spacing:.04em}
.clock-row strong{display:block;font:37px var(--font-display);color:#f2dfd8;margin:7px 0}
.clock-track{display:block;width:100%;height:3px;background:#4d3949}.clock-track i{display:block;height:100%;background:#cc7593}
.clock-track.rest i{width:7%}.clock-track.dilated i{width:100%;background:#e2b379}
.clock-note{font-size:10px;color:#af9da5;line-height:1.8;margin:22px 0 0}

/* Experiment: independently recomputed proper lifetime and probability. */
.simulation-section{background:radial-gradient(ellipse at 90% 25%,#261922,transparent 51%),#121116;color:#f3eee6}
.simulation-section .lesson-section-tag{border-color:#56414a}
.sim-heading,.math-heading,.quiz-heading,.sources-heading{display:flex;align-items:end;justify-content:space-between;gap:65px;margin-bottom:45px}
.sim-heading>p,.sources-heading>p{max-width:400px;color:#b5a7af;font-size:13px;line-height:1.85;margin:0}
.sim-heading h2 em{color:#ddaf80}
.sim-grid{display:grid;grid-template-columns:.93fr 1.07fr;border:1px solid #634653}
.sim-atmosphere{display:flex;flex-direction:column;min-height:560px;background:linear-gradient(180deg,#121626,#2a202f 68%,#422b37 93%,#1c1922);border-right:1px solid #614658}
.sim-topline,.sim-schematic{display:flex;justify-content:space-between;gap:15px;color:#d1abba;padding:22px 24px;font:9px var(--font-mono);letter-spacing:.07em}
.sim-topline span:last-child{color:#edb980}
.sim-sky{flex:1;position:relative;overflow:hidden;background:radial-gradient(ellipse at 50% 60%,rgba(189,94,134,.12),transparent 60%)}
.sim-star{position:absolute;width:3px;height:3px;background:#e8b7bc;box-shadow:0 0 12px 4px rgba(232,175,173,.33)}.sim-star.a{top:16%;left:19%}.sim-star.b{top:30%;right:19%}.sim-star.c{bottom:32%;left:26%}
.sim-track{position:absolute;left:50%;top:12%;bottom:3%;width:2px;background:repeating-linear-gradient(to bottom,#e5adc3 0 7px,transparent 7px 16px);box-shadow:0 0 25px #a54470}
.sim-track::after{content:'';position:absolute;left:-2px;top:0;width:6px;height:6px;border-radius:50%;background:#eab7cf;box-shadow:0 0 21px 8px rgba(216,106,158,.42);animation:sim-descend 4.5s linear infinite}
@keyframes sim-descend{0%{top:0;opacity:0}12%{opacity:1}88%{opacity:1}100%{top:99%;opacity:0}}
.sim-particle{position:absolute;top:31%;left:-21px;width:44px;height:44px;display:grid;place-items:center;border-radius:50%;background:#c84f7b;box-shadow:0 0 0 13px rgba(186,64,111,.1),0 0 40px #a64580;font:31px var(--font-display);transition:top .2s}
.sim-dash{position:absolute;left:-40px;top:55%;width:80px;height:1px;background:rgba(235,201,219,.13)}
.sim-arrow{position:absolute;bottom:-2px;left:-6px;color:#e9b489;font-size:16px}
.sim-model-tag{position:absolute;top:50%;right:25px;color:#ac9aaf;font:9px/1.7 var(--font-mono);letter-spacing:.06em;text-align:right}
.sim-ground{display:flex;align-items:center;gap:14px;padding:18px 24px;border-top:1px solid #e5b787;color:#efcdb3;background:#1d1922;font:9px var(--font-mono);letter-spacing:.08em}
.sim-ground i{width:30px;height:19px;border:1px solid #d7ac7d;box-shadow:4px -4px 0 -1px #1c1922,4px -4px 0 #a88178}
.sim-schematic{padding-block:12px;color:#9a8b9c;background:#1b1720}
.sim-panel{padding:33px 35px 30px;background:#231c27}
.sim-panel-header{display:flex;justify-content:space-between;gap:10px;padding-bottom:24px;border-bottom:1px solid #514050;color:#ddbb8b;font:10px var(--font-mono);letter-spacing:.08em}
.sim-status{color:#b5a8ad;font-size:9px}.sim-status i{display:inline-block;width:6px;height:6px;background:#ddba85;border-radius:50%;margin-right:5px}
.sim-control{margin-top:35px}.sim-label-row{display:flex;justify-content:space-between;gap:12px;color:#e3d9d6;font-size:13px}
.sim-label-row output{color:#e9c08e;font:13px var(--font-mono)}
.sim-control input[type=range]{display:block;width:100%;accent-color:#c65576;margin:27px 0 15px;cursor:pointer}
.sim-range-labels{display:flex;justify-content:space-between;gap:15px;color:#938895;font:9px var(--font-mono)}
.sim-values{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));margin-top:36px;border-block:1px solid #564253}
.sim-values>div{min-width:0;padding:20px 0}.sim-values>div:nth-child(odd){padding-right:15px}.sim-values>div:nth-child(even){border-left:1px solid #564253;padding-left:20px}.sim-values>div:nth-child(n+3){border-top:1px solid #564253}
.sim-values small{display:block;color:#b0a1aa;font:9px var(--font-mono);letter-spacing:.05em}
.sim-values strong{font:43px/1.2 var(--font-display);color:#f5e5da;display:inline-block;margin-top:8px;max-width:100%;overflow-wrap:anywhere}
.sim-values span{font:11px var(--font-mono);color:#d59cb0;margin-left:6px}
.sim-reset{display:block;background:none;border:0;border-bottom:1px solid #9f6a7c;color:#e9bac7;font-size:11px;padding:4px 0;margin-top:30px;text-align:left}
.survival-compare{border:1px solid #614957;border-top:0;padding:33px 36px 37px;background:#1d1821}
.compare-head{display:flex;justify-content:space-between;align-items:center;gap:23px}
.compare-head>div:first-child>span{font:9px var(--font-mono);letter-spacing:.12em;color:#d9ab7a}
.compare-head h3{font-size:37px;margin:11px 0 18px}.compare-head h3 em{color:#d6b085}
.compare-toggle,.math-level-switch{display:flex;flex-wrap:wrap;border:1px solid #685061}
.comparison-mode,.math-level{border:0;background:transparent;color:#b5a8af;padding:12px 16px;font-size:11px;transition:background .2s,color .2s}
.comparison-mode+.comparison-mode,.math-level+.math-level{border-left:1px solid #685061}
.comparison-mode.active,.math-level.active{background:#8c334f;color:#fff}
.compare-results{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.result-box{min-width:0;border:1px solid #664d59;padding:28px 26px;background:#251d28;opacity:.65;transition:opacity .2s,border-color .2s}
.result-box.emphasis{opacity:1;border-color:#bb7184;background:#312230}
.result-box small{display:block;color:#d9afbe;font:9px var(--font-mono);letter-spacing:.1em}
.result-box strong{display:block;overflow-wrap:anywhere;color:#f8e3db;font:clamp(32px,3.8vw,54px) var(--font-display);line-height:1.1;margin:18px 0 8px}
.result-box>span{display:block;color:#bfaab4;font-size:11px}
.result-box .result-mean-path{margin-top:10px;color:#b99eaa;font:10px var(--font-mono)}
.result-mean-path b{color:#e2b883;font-weight:500}
.result-bar{height:5px;background:#473443;margin-top:21px;overflow:hidden}.result-bar i{display:block;height:100%;background:linear-gradient(90deg,#b8496e,#dbb17d);transition:width .3s;width:0}
.compare-explanation{color:#c7b4bb;font-size:12px;line-height:1.8;margin:23px 0 0}
.scientific-warning{display:grid;grid-template-columns:180px 1fr;gap:23px;border-left:2px solid #bc9271;background:#262129;padding:23px 26px;margin-top:24px}
.scientific-warning>span{font:9px/1.7 var(--font-mono);color:#e3b585;letter-spacing:.07em}
.scientific-warning p{margin:0;color:#bdb0b8;font-size:11px;line-height:1.85}.scientific-warning strong{color:#e8d1c4}

/* Two inertial descriptions. */
.frames-section{background:var(--paper);color:var(--ink)}
.frame-comparison{border:1px solid var(--line);background:var(--surface)}
.frame-tabs{display:grid;grid-template-columns:1fr 1fr;border-bottom:1px solid var(--line)}
.frame-tabs button{padding:18px 13px;background:transparent;color:var(--ink-muted);border:0;font-size:12px}
.frame-tabs button+button{border-left:1px solid var(--line)}
.frame-tabs button[aria-selected=true]{color:#ce7289;box-shadow:inset 0 -2px #cb6b83;font-weight:700}
.frame-diagram{padding:38px 33px 20px;min-height:225px;display:grid;align-items:center}
.frame-scale{display:flex;align-items:center;flex-direction:column;justify-content:center;gap:14px;color:var(--ink-muted);font:9px var(--font-mono);letter-spacing:.06em}
.frame-path{position:relative;width:100%;max-width:100%;height:2px;background:linear-gradient(90deg,#b04e71,#dfb985);transition:width .35s;min-width:13%;margin:35px auto}
.frame-path::before,.frame-path::after{content:'';position:absolute;top:-6px;width:2px;height:15px;background:var(--ink-muted)}.frame-path::before{left:0}.frame-path::after{right:0}
.frame-muon-marker{position:absolute;left:45%;top:-20px;width:42px;height:42px;display:grid;place-items:center;border-radius:50%;background:#b94a70;color:white;font:27px var(--font-display);box-shadow:0 0 25px #b9678c55}
.frame-measurements{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.frame-measurements>div{padding:18px 17px;min-width:0}.frame-measurements>div+div{border-left:1px solid var(--line)}
.frame-measurements small{display:block;color:var(--ink-muted);font:8px/1.6 var(--font-mono);min-height:27px}
.frame-measurements strong{display:block;overflow-wrap:anywhere;font:27px/1.2 var(--font-display);color:#c17e8c;margin-top:8px}
.frame-caption{padding:0 24px;color:var(--ink-muted);font-size:12px;line-height:1.8}
.frame-footnote{font-size:12px;color:var(--ink-muted);margin:32px 0 0;line-height:1.8;border-top:1px solid var(--line);padding-top:24px}

/* Derivation, formative assessment, and the paper trail. */
.mathematics-section{background:var(--surface);border-block:1px solid var(--line)}
.math-heading h2{margin-bottom:0}
.math-level-switch{border-color:var(--line)}
.math-level{color:var(--ink-muted)}.math-level+.math-level{border-color:var(--line)}
.math-content{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));border:1px solid var(--line)}
.math-story{padding:30px 22px 34px;min-height:290px}
.math-story+.math-story{border-left:1px solid var(--line)}
.math-step{font:11px var(--font-mono);color:#ba7184}
.math-story h3{font-size:26px;line-height:1.07;margin:39px 0 16px}
.math-story p{color:var(--ink-muted);font-size:11px;line-height:1.87}
.math-technical{display:block;border:0}
.math-technical details{border:1px solid var(--line);background:var(--paper);margin-bottom:12px}
.math-technical summary{cursor:pointer;padding:22px 25px;color:var(--ink);font:21px var(--font-display)}
.math-technical details[open] summary{border-bottom:1px solid var(--line)}
.derivation-body{padding:18px 25px 27px}.derivation-body p{color:var(--ink-muted);line-height:1.85;font-size:13px;max-width:810px}
.quiz-section{background:var(--paper)}
.quiz-heading h2{margin:0}
.quiz-score{flex:0 0 155px;border-left:1px solid var(--line);padding-left:24px;display:flex;flex-direction:column;gap:9px}
.quiz-score>span,.quiz-score small{font:10px var(--font-mono);color:var(--ink-muted);letter-spacing:.08em}
.quiz-score strong{font:63px var(--font-display);line-height:1;color:#bd7186}
.quiz-questions{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:17px;align-items:stretch}
.quiz-item{border:1px solid var(--line);background:var(--surface);padding:28px 27px 30px;min-width:0}
.quiz-item:last-child{grid-column:1/-1}
.quiz-number{font:10px var(--font-mono);letter-spacing:.07em;color:#b87d88}
.quiz-item h3{font-size:27px;line-height:1.18;margin:20px 0 25px;min-height:62px}
.quiz-options{display:grid;gap:8px}
.quiz-option{display:flex;align-items:center;gap:14px;text-align:left;padding:12px 15px;background:var(--paper);border:1px solid var(--line);color:var(--ink);font-size:12px;line-height:1.5;transition:border-color .2s,background .2s}
.quiz-option:hover:not(:disabled){border-color:#c1788c;background:var(--card-hover)}
.quiz-option:disabled{cursor:default;opacity:.7}
.quiz-option.correct{border-color:#5a9b7b;background:rgba(64,154,99,.11);opacity:1}.quiz-option.incorrect{border-color:#be5c6a;background:rgba(190,65,91,.12);opacity:1}
.option-letter{display:grid;place-items:center;flex:0 0 27px;width:27px;height:27px;background:var(--surface-alt);color:#bb7a8d;font:11px var(--font-mono)}
.quiz-explanation{margin:17px 0 0;padding:15px 17px;border-left:2px solid #c28b79;background:var(--paper);color:var(--ink-muted);font-size:12px;line-height:1.75}
.quiz-finish{margin-top:26px;padding:33px;border:1px solid #b77c8a;background:var(--surface)}
.quiz-finish>strong{font:36px var(--font-display);color:var(--ink)}.quiz-finish>p{color:var(--ink-muted);font-size:13px}
.quiz-finish>div{display:flex;flex-wrap:wrap;gap:12px;margin-top:23px}
.connections-section{background:var(--surface);border-block:1px solid var(--line)}
.connections-section h2{margin-bottom:47px}
.connections-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));border:1px solid var(--line)}
.connections-grid article{padding:28px 23px;min-height:257px}
.connections-grid article+article{border-left:1px solid var(--line)}
.connections-grid span{font:9px var(--font-mono);color:#b97889;letter-spacing:.06em}
.connections-grid h3{font:31px/1.1 var(--font-display);margin:36px 0 14px}
.connections-grid p{color:var(--ink-muted);font-size:11px;line-height:1.85}
.lab-story{display:grid;grid-template-columns:240px 1fr;gap:55px;margin-top:34px;border:1px solid #694854;background:radial-gradient(ellipse at 85% 20%,#3b2738,transparent 58%),#231b25;color:#f4e9e4;padding:40px}
.lab-story-label{display:flex;flex-direction:column;justify-content:space-between;align-items:start;gap:23px;color:#dbad80;font:10px var(--font-mono);letter-spacing:.07em}
.lab-story-label span{font:48px var(--font-display);color:#ac7387}
.lab-story h3{font:41px/1.09 var(--font-display);margin:0 0 17px}
.lab-story p{color:#c4b5bf;font-size:13px;line-height:1.9}.lab-story>div:last-child>span{font:9px var(--font-mono);color:#d8b384;letter-spacing:.07em}
.sources-section{background:var(--paper)}
.sources-heading>p{color:var(--ink-muted)}
.lesson-reference-list{border-top:1px solid var(--line)}
.lesson-reference-list a{display:grid;grid-template-columns:55px 1fr 29px;align-items:center;gap:22px;padding:23px 0;border-bottom:1px solid var(--line);transition:padding .2s}
.lesson-reference-list a:hover{padding-left:10px}
.lesson-reference-list a>span{font:10px var(--font-mono);color:#ba7287}
.lesson-reference-list a strong{font:25px var(--font-display);display:block}
.lesson-reference-list a small{font-size:11px;color:var(--ink-muted);display:block;margin-top:4px}
.lesson-reference-list a b{font:24px var(--font-display);color:#b47c85}
.lesson-correction-note{font-size:12px;color:var(--ink-muted);border-left:2px solid #b98f6b;padding:16px 25px;background:var(--surface);line-height:1.8;margin-top:34px}
.lesson-closing{background:radial-gradient(ellipse at 70% 30%,#3a1c2b,transparent 62%),#161117;color:#f3eee6;padding:81px 0 90px}
.lesson-closing .shell{display:flex;justify-content:space-between;align-items:end;gap:35px}
.lesson-closing .shell>div:first-child>span{color:#d4b181;font:10px var(--font-mono);letter-spacing:.08em}
.lesson-closing h2{font:clamp(57px,6vw,85px)/.93 var(--font-display);margin:23px 0}.lesson-closing h2 em{color:#d7b284}
.lesson-closing p{font-size:13px;color:#bba9b2}
.lesson-closing .shell>div:last-child{display:flex;flex-direction:column;gap:14px}
.lesson-closing .archive-button.outlined{border-color:#644552}

/* Fluid layouts: the archive must remain functional on phones and tablets. */
@media(max-width:1150px){
  .archive-hero-grid{grid-template-columns:60% 40%}.archive-hero-art{right:-12%;width:57%}
  .lesson-chapters{top:70px}.lesson-section{scroll-margin-top:142px}
  .math-content{grid-template-columns:repeat(3,minmax(0,1fr))}.math-story:nth-child(4){border-left:0;border-top:1px solid var(--line)}.math-story:nth-child(5){border-top:1px solid var(--line)}
  .connections-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.connections-grid article:nth-child(3){border-left:0;border-top:1px solid var(--line)}.connections-grid article:nth-child(4){border-top:1px solid var(--line)}
}
@media(max-width:900px){
  .archive-hero-grid{display:block;min-height:600px}.archive-hero-copy{padding:80px 0}.archive-hero-art{right:-33%;width:90%;opacity:.55}
  .archive-hero h1{font-size:clamp(76px,11vw,108px)}
  .featured-layout{grid-template-columns:1fr;gap:43px}.featured-formula{max-width:670px;min-height:270px}
  .promise-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.promise-grid>div:nth-child(3){border-left:0;border-top:1px solid #4a3c44}.promise-grid>div:nth-child(4){border-top:1px solid #4a3c44}
  .lesson-hero-inner{display:block;min-height:670px}.lesson-hero-copy{max-width:650px}.lesson-hero-art{position:absolute;right:-35%;top:5%;bottom:0;width:75%;min-height:unset;opacity:.35;pointer-events:none}
  .lesson-two-col{grid-template-columns:1fr;gap:45px}.shower-diagram{max-width:630px}.clock-comparison{max-width:650px}
  .video-layout{grid-template-columns:minmax(0,1.6fr) minmax(190px,.72fr)}
  .sim-grid{grid-template-columns:1fr}.sim-atmosphere{min-height:320px;border-right:0;border-bottom:1px solid #614658}.sim-sky{min-height:215px}.sim-panel{padding:35px}
  .sim-heading,.math-heading,.quiz-heading,.sources-heading{align-items:start;flex-direction:column;gap:18px}
  .math-heading h2,.quiz-heading h2{margin-bottom:0}
  .archive-outro{align-items:start;flex-direction:column}
  .lesson-closing .shell{align-items:start;flex-direction:column}
}
@media(max-width:620px){
  .physics-archive .archive-section-heading,.physics-archive .lesson-section-tag{align-items:start;gap:10px}.physics-archive .archive-mark,.physics-archive .lesson-section-tag span:last-child{font-size:8px;text-align:right}
  .physics-archive .archive-button{font-size:11px;padding:14px 16px;gap:12px}
  .archive-hero-grid{min-height:570px}.archive-hero-copy{padding:75px 0 54px}.archive-hero h1{font-size:clamp(65px,13vw,81px);margin:30px 0}.archive-hero-copy>p{font-size:14px}.archive-hero-trust{font-size:7px;gap:9px;flex-wrap:wrap;margin-top:59px}.archive-hero-art{right:-67%;width:120%}
  .archive-feature{padding-top:68px;padding-bottom:85px}.featured-layout{margin-top:35px}.featured-intro h2{font-size:clamp(44px,11vw,59px)}.featured-intro>p:not(.archive-mini-label){font-size:13px}.featured-meta{font-size:8px}.featured-formula{padding:25px;min-height:260px;box-shadow:12px 12px 0 -1px var(--paper),12px 12px 0 var(--line)}.featured-gamma{font-size:54px}
  .archive-library-title{align-items:start;flex-direction:column;margin:42px 0 29px}.archive-library-title h2{font-size:58px}.library-total strong{font-size:52px}.library-total{padding-left:14px}
  .lesson-filters{flex-wrap:nowrap;overflow-x:auto;margin-right:-22px;padding-right:22px;padding-bottom:6px;scrollbar-width:thin}.lesson-filter{flex:0 0 auto}
  .lesson-cards{grid-template-columns:1fr}.lesson-card-art{height:190px}
  .archive-promise{padding:70px 0 80px}.archive-promise h2{font-size:52px}.promise-grid{grid-template-columns:1fr}.promise-grid>div{min-height:unset;padding:24px}.promise-grid>div+div,.promise-grid>div:nth-child(3),.promise-grid>div:nth-child(4){border-left:0;border-top:1px solid #4a3c44}.promise-grid strong{margin-top:16px}
  .archive-outro{padding-top:70px;padding-bottom:80px}.archive-outro h2{font-size:44px}
  .lesson-hero-inner{min-height:620px}.lesson-hero-copy{padding:77px 0 67px}.lesson-hero h1{font-size:clamp(52px,12vw,74px)}.lesson-subtitle{font-size:14px}.lesson-badges{gap:9px;font-size:8px}.lesson-badges span+span{padding-left:9px}.lesson-hero-art{right:-62%;width:120%}.lesson-chapters{top:64px}.lesson-chapters .shell{gap:22px}.lesson-chapters a{font-size:9px;padding:14px 0}
  .lesson-section{padding:73px 0 85px;scroll-margin-top:135px}.lesson-section-tag{margin-bottom:42px}
  .lesson-prose h2,.sim-heading h2,.math-heading h2,.quiz-heading h2,.sources-heading h2,.connections-section h2{font-size:clamp(45px,10.6vw,57px)}.lesson-prose p:not(.section-kicker){font-size:13px}
  .shower-diagram{min-height:365px}.concept-callout{display:block;padding:18px}.concept-callout>span{display:block;margin-bottom:10px}
  .lesson-video-section{padding:55px 0}.video-layout{grid-template-columns:1fr}.video-frame.portrait{width:min(245px,90%);height:auto;max-height:none}.video-title-row{align-items:start;flex-direction:column}.video-empty strong{font-size:23px}
  .clock-comparison{padding:21px;box-shadow:none}.clock-row{gap:12px}.clock-icon{flex-basis:53px;height:53px;font-size:16px}.clock-row strong{font-size:32px}
  .sim-heading{margin-bottom:32px}.sim-heading>p{font-size:12px}.sim-panel{padding:23px 20px}.sim-atmosphere{min-height:300px}.sim-topline{padding:15px;font-size:8px}.sim-model-tag{font-size:7px;right:12px}.sim-ground{padding:15px;font-size:8px}
  .sim-values strong{font-size:36px}.sim-values small{font-size:8px}.sim-values>div:nth-child(even){padding-left:14px}
  .survival-compare{padding:25px 18px}.compare-head{align-items:start;flex-direction:column}.compare-head h3{font-size:32px}.compare-results{grid-template-columns:1fr}.result-box strong{font-size:43px}.scientific-warning{grid-template-columns:1fr;padding:19px;gap:10px}
  .frame-diagram{padding:25px 15px;min-height:205px}.frame-measurements{grid-template-columns:1fr}.frame-measurements>div{padding:15px}.frame-measurements>div+div{border-left:0;border-top:1px solid var(--line)}.frame-measurements small{min-height:0}
  .math-level-switch{width:100%}.math-level{flex:1;font-size:10px;padding:12px 10px}.math-content{grid-template-columns:1fr}.math-story{min-height:0;padding:21px}.math-story+.math-story,.math-story:nth-child(4),.math-story:nth-child(5){border-left:0;border-top:1px solid var(--line)}.math-story h3{margin:15px 0 9px;font-size:26px}.math-technical summary{padding:16px;font-size:19px}.derivation-body{padding:13px 16px}.math-display{font-size:19px;padding:15px 9px}
  .quiz-score{flex-basis:auto;padding-left:15px}.quiz-score strong{font-size:47px}.quiz-questions{grid-template-columns:1fr}.quiz-item:last-child{grid-column:auto}.quiz-item{padding:23px 19px}.quiz-item h3{font-size:25px;min-height:0}.quiz-option{padding:11px}
  .connections-grid{grid-template-columns:1fr}.connections-grid article{min-height:0}.connections-grid article+article,.connections-grid article:nth-child(3),.connections-grid article:nth-child(4){border-left:0;border-top:1px solid var(--line)}.connections-grid h3{margin-top:19px}
  .lab-story{grid-template-columns:1fr;gap:22px;padding:24px}.lab-story-label{flex-direction:row}.lab-story-label span{font-size:28px}.lab-story h3{font-size:35px}
  .sources-heading>p{font-size:12px}.lesson-reference-list a{grid-template-columns:24px 1fr 20px;gap:10px}.lesson-reference-list a strong{font-size:21px}.lesson-reference-list a small{font-size:10px}
  .lesson-closing{padding:65px 0}.lesson-closing h2{font-size:64px}
  .homepage-feature{padding-top:65px;padding-bottom:72px}
}
@media(prefers-reduced-motion:reduce){.physics-archive *{animation:none!important;transition:none!important}}