:root{--bg:#07151d;--surface:#10242e;--surface2:#142d39;--line:#29424d;--text:#e8f1f4;--muted:#a0b5bf;--accent:#61e7c9;--accent-dim:#1e4945;--orange:#ffbd73;--error:#ffad9f;--radius:18px;--mono:ui-monospace,SFMono-Regular,Consolas,monospace}
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p{font-size:14px;color:var(--muted)}.verdict{padding:31px;border-radius:16px;background:#123332;border:1px solid #355d56;margin:31px 0}.verdict h2{font-size:clamp(21px,2vw,28px);line-height:1.6;margin:17px 0}.verdict p{color:var(--muted);font-size:14px;margin-bottom:0}.quiz-progress{display:flex;gap:10px;margin:28px 0 20px}.quiz-dot{width:36px;height:36px;border:1px solid var(--line);border-radius:50%;display:grid;place-items:center;font:14px var(--mono);color:var(--muted)}.quiz-dot.current{border-color:var(--accent);color:var(--accent)}.quiz-dot.correct{background:var(--accent);color:var(--bg);border-color:var(--accent)}.quiz-dot.incorrect{border-color:var(--orange);color:var(--orange)}.quiz-card{max-width:890px;min-height:365px;padding:30px}.quiz-card h2{font-size:23px;margin:12px 0 26px}.quiz-options{display:grid;gap:11px}.quiz-option{text-align:left;padding:15px 18px;border:1px solid var(--line);background:#132d39}.quiz-option.selected{border-color:var(--accent);background:#1c4540}.quiz-option.correct-answer{border-color:var(--accent)}.quiz-feedback{margin:22px 0;padding:19px;background:#0b1e26;border-radius:10px;font-size:15px;color:var(--muted)}.quiz-feedback strong{display:block;color:var(--accent);margin-bottom:9px}.quiz-controls{display:flex;gap:12px;margin-top:22px;flex-wrap:wrap}.score-number{font:74px var(--mono);color:var(--accent);margin:15px 0}.review-line{padding:13px 0;border-bottom:1px solid var(--line);font-size:14px}.review-line a{margin-left:10px}.review-line p{color:var(--muted);margin-top:6px}.review-line span{color:var(--orange)}dialog{background:#112833;color:var(--text);border:1px solid #45626c;border-radius:18px;width:min(720px,calc(100% - 28px));max-height:85vh;padding:30px;line-height:1.8}dialog::backdrop{background:#020b11cf;backdrop-filter:blur(5px)}.dialog-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:24px;gap:20px}dialog p{font-size:14px;color:var(--muted)}.sources-list{padding-left:22px}.sources-list li{margin:18px 0;font-size:14px}.sources-list p{font-size:13px;margin:4px 0}.pulse-dot{transition:cy .6s,cx .6s,opacity .3s}.state-arrow{transition:x2 .3s,y2 .3s}.phase-path{transition:stroke .2s}.energy-pulse{animation:energy-pulse .7s ease-out}.prob-point{transition:cx .35s,cy .35s}.no-motion *,.no-motion *::before,.no-motion *::after{animation:none!important;transition:none!important;scroll-behavior:auto!important}
@keyframes page-in{from{opacity:0;transform:translateY(7px)}to{opacity:1;transform:translateY(0)}}@keyframes digit-change{0%{background:var(--accent);color:var(--bg);transform:translateY(-4px)}100%{transform:translateY(0)}}@keyframes energy-pulse{0%{opacity:0}40%{opacity:1}100%{opacity:0}}
.encoding-strip{display:grid;grid-template-columns:1.3fr 1fr;gap:32px;margin:24px 0 28px;padding:0 4px 22px;border-bottom:1px solid var(--line);align-items:center}.encoding-strip h3{font-size:16px}.encoding-strip p{font-size:14px;color:var(--muted);margin:10px 0 0}.encoding-levels{display:flex;flex-direction:column;gap:9px}.encoding-level{display:flex;align-items:center;gap:15px;color:#889da8;font:13px var(--mono)}.encoding-level .level-line{height:2px;background:var(--line);flex:1}.encoding-level b{width:60px;text-align:right;font-weight:400}.encoding-level.used{color:var(--accent)}.encoding-level.used .level-line{background:var(--accent)}.mobile-chart-hint{display:none}
.digit-train{flex-wrap:nowrap;overflow-x:auto}.digit-cell{flex-shrink:0}
@media(max-width:400px){.base-row{grid-template-columns:1fr}.base-label{display:flex;align-items:center;gap:10px}.base-label small{margin:0}.digit-train{justify-content:flex-start}}
@media(max-width:900px){.interference-lab .diagram{overflow-x:auto}.interference-lab .diagram svg{min-width:740px}.mobile-chart-hint{display:block;font-size:12px!important;color:var(--muted)}}
@media(max-width:560px){.encoding-strip{grid-template-columns:1fr;gap:18px}.encoding-levels{max-width:290px}}
@media(min-width:1550px){main{padding-top:48px}.lab-grid{gap:24px}.panel{padding:30px}.digit-cell{font-size:32px}.group-visual{min-height:260px}}
@media(max-width:1180px){.sidebar{width:230px;padding-inline:15px}.app-shell{margin-left:230px}.topbar{padding-inline:28px}main{padding-inline:28px}.lab-grid{grid-template-columns:1fr}.group-visual{min-height:170px}.number-map{display:block}.number-lab .digit-cell{font-size:28px}.number-entry input{font-size:38px}.three-columns,.comparison-cards{gap:20px}.interference-controls{grid-template-columns:1fr}.state-canvas .diagram{max-width:500px;margin:auto}.nav-item{font-size:13px}}
@media(max-width:760px){.sidebar{position:relative;width:100%;padding:18px 18px 0;border-right:0;border-bottom:1px solid var(--line);overflow:visible}.brand{font-size:17px}.brand-mark{font-size:34px}.course-tag,.nav-heading,.sidebar-bottom{display:none}.sidebar nav{display:flex;overflow-x:auto;gap:5px;margin:18px -18px 0;padding:0 14px 9px}.nav-item{width:auto;min-width:max-content;min-height:44px;padding:10px;gap:7px;margin:0;font-size:13px}.nav-item small,.nav-state{display:none}.nav-num{font-size:12px;padding-top:2px}.app-shell{margin:0}.topbar{padding:0 20px;height:58px}.top-actions{gap:7px}.status-label{display:none}main{padding:25px 20px 20px}h1{letter-spacing:-.03em}.eyebrow{font-size:11px;gap:10px}.eyebrow span{font-size:11px}.lead{font-size:15px}.panel{padding:20px}.panel-head h2{font-size:18px}.panel-head .mini-label{font-size:10px}.three-columns,.comparison-cards,.concept-flow{grid-template-columns:1fr;gap:20px}.noise-diagrams{grid-template-columns:1fr;gap:25px}.noise-col{display:grid;grid-template-columns:120px 1fr;align-items:center}.noise-col h3{grid-column:1/3}.noise-col svg{grid-row:2;max-height:270px}.noise-col .noise-result{padding:0 15px}.table-wrap{margin-inline:0}th,td{padding:12px;min-width:126px;font-size:13px}.takeaway{gap:14px}.takeaway-symbol{flex-basis:34px;width:34px;height:34px;font-size:26px}.takeaway h3{font-size:16px}.takeaway p{font-size:13px}.wide-segment button{white-space:normal;font-size:13px;min-width:150px}.quiz-card{padding:22px}.quiz-card h2{font-size:20px}.page-footer{font-size:10px}.page-footer button{font-size:11px}.result-pair{gap:14px}.result-pair>div{flex-direction:column;align-items:flex-start;gap:8px}.result-pair b{font-size:28px}.verdict{padding:23px}.section-heading{align-items:flex-start;flex-direction:column;gap:6px}.segmented button{font-size:13px;padding:9px}.base-row{grid-template-columns:52px 1fr;gap:7px}.digit-train{gap:3px}.number-lab .digit-cell{font-size:20px;padding:5px;min-width:23px}.group-visual{gap:8px}.group-block{width:68px}.group-symbol{font-size:16px}.formula{font-size:16px}.number-entry{gap:8px}.entry-range{font-size:11px}}
@media(prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important;scroll-behavior:auto!important}}