.demo-page{--reading-width:1080px;font-family:'Helvetica Neue',Helvetica,Arial,sans-serif}.demo-page header{height:66px;padding:0 max(24px,calc((100vw - 1080px)/2));gap:22px}.demo-page header .brand{margin-right:auto;font-size:12px;letter-spacing:.02em}.demo-page header .home-nav{font-size:14px}.demo-main{max-width:var(--reading-width);margin:auto;padding:0 28px 70px}.demo-page [hidden]{display:none!important}.demo-page button{font-family:inherit}.demo-page section{scroll-margin-top:28px}.lesson-opening{padding:64px 0 40px}.lesson-index{font-size:15px;letter-spacing:-.01em;margin:0 0 26px;color:var(--muted)}.lesson-index span{margin:0 12px;color:#9b9ba3}.demo-main .lesson-opening h1{font-size:clamp(46px,6.7vw,82px);line-height:.98;letter-spacing:-.065em;font-weight:650;margin:0 0 26px;max-width:920px}.lesson-intro{font-size:21px;line-height:1.5;letter-spacing:-.02em;max-width:640px;margin:0}.lesson-meta{display:flex;align-items:center;gap:25px;margin-top:30px;font-size:13px;color:var(--muted)}.lesson-meta a{margin-left:auto;text-decoration:none;font-size:14px}.lesson-meta a span{margin-left:10px}.section-number{display:block;font-size:13px;color:var(--muted);font-weight:400;letter-spacing:0}.lab-heading{display:flex;align-items:end;justify-content:space-between;padding:24px 0 12px;border-top:1px solid var(--line)}.lab-heading h2{font-size:25px;letter-spacing:-.04em;font-weight:550;margin:7px 0}.xp-pill{font-size:12px;color:var(--muted);padding-bottom:8px}.lab-tabs{display:flex;gap:0;border-bottom:1px solid var(--line);margin-bottom:18px;overflow-x:auto}.lab-tabs button{flex:1;white-space:nowrap;border:0;border-bottom:2px solid transparent;border-radius:0;padding:14px 8px;font-size:13px;color:var(--muted);background:none;transition:color .2s,border-color .2s}.lab-tabs button span{display:none}.lab-tabs button.selected{border-bottom-color:#0071e3;color:var(--ink);font-weight:600}.lab-tabs button:hover{background:var(--panel)}.lab-tabs .explored:not(.selected)::after{content:' ·';color:#3c9271}.lab-workspace{display:grid;grid-template-columns:minmax(0,1.25fr) minmax(310px,1fr);border:1px solid var(--line);border-radius:16px;overflow:hidden;background:var(--panel)}.lab-visual{background:radial-gradient(ellipse at 55% 10%,#233752,#121d2e 75%);display:flex;flex-direction:column;justify-content:center;min-width:0}.lab-visual svg{display:block;width:100%;height:auto;max-height:320px}.lab-chart-key{display:flex;gap:15px;flex-wrap:wrap;padding:5px 22px 18px;color:#aab8cd;font-size:11px}.lab-chart-key i{display:inline-block;width:6px;height:10px;background:#69baff;border-radius:1px;margin-right:5px}.lab-chart-key .down{background:#e4a37f}.lab-instructions{padding:23px 26px;min-height:330px}.lab-instructions h3{font-size:23px;line-height:1.17;letter-spacing:-.04em;font-weight:550;margin:0 0 13px}.lab-instructions>p{font-size:15px;line-height:1.55;margin:0 0 16px;color:var(--muted)}.lab-instructions label{display:flex;justify-content:space-between;font-size:14px;margin-top:12px}.lab-instructions input[type=range]{width:100%;min-height:32px;accent-color:#0071e3}.lab-metrics{display:flex;gap:30px;margin:8px 0}.lab-metrics div{display:grid;grid-template-columns:auto auto;align-items:baseline;column-gap:7px}.lab-metrics small{grid-column:1/-1;font-size:10px;letter-spacing:.04em;color:var(--muted)}.lab-metrics b{font-size:28px;font-weight:550;letter-spacing:-.04em}.lab-metrics span{font-size:12px;color:var(--muted)}.lab-feedback{font-size:14px;line-height:1.5;margin-top:12px;color:var(--ink)}.lab-feedback button{display:block;margin-top:10px;font-size:14px;padding:9px 14px}.lab-choice-row,.level-picks{display:flex;gap:8px;flex-wrap:wrap;margin:14px 0}.lab-choice-row button,.level-picks button{padding:10px 13px;font-size:14px}.lab-choice-row button[aria-pressed=true],.level-picks button[aria-pressed=true]{background:#e4f0ff;color:#0055aa;border-color:#0071e3}.lab-choice-stack{display:grid;gap:8px}.lab-choice-stack button{text-align:left;font-size:14px;padding:11px 14px}.control-label{font-size:14px;margin:12px 0}.lab-bottom{display:flex;align-items:center;justify-content:space-between;gap:20px;padding:14px 0 0;font-size:12px;color:var(--muted)}.lab-bottom .primary{font-size:14px;padding:11px 18px}.lab-candle{animation:barReveal .4s both;transform-origin:center bottom;transform-box:fill-box}.lab-workspace[data-view="0"] .lab-candle{animation:none}.reference-line{stroke-dasharray:7 4;animation:referenceReveal .7s ease-out both}.lab-workspace[data-view="0"] .reference-line{animation:none}
.lesson-summary{display:grid;grid-template-columns:1fr 1.8fr;gap:65px;padding:60px 0;border-bottom:1px solid var(--line);margin-top:30px}.summary-heading h2{font-size:37px;font-weight:550;letter-spacing:-.055em;line-height:1.05;margin:15px 0 20px}.summary-heading>p{font-size:16px;line-height:1.6;max-width:270px;color:var(--muted)}.summary-copy>p{font-size:17px;line-height:1.75;margin:0 0 24px;letter-spacing:-.01em;color:var(--muted)}.summary-copy strong{font-weight:600;color:var(--ink)}.worked-note{border-left:2px solid #0071e3;padding:3px 0 3px 24px;margin-top:34px}.worked-note>span{font-size:13px;color:var(--muted)}.worked-note blockquote{font-size:20px;line-height:1.55;letter-spacing:-.025em;font-weight:450;margin:15px 0;color:var(--ink)}.worked-note p{font-size:15px;line-height:1.65;margin:16px 0 0;color:var(--muted)}.section-enter .summary-heading,.section-enter>.section-top{animation:sectionArrival .6s cubic-bezier(.2,.7,.2,1) both}
.demo-quiz{padding:54px 0 0}.section-top{display:flex;justify-content:space-between;align-items:end;gap:20px}.section-top h2{font-size:38px;font-weight:550;letter-spacing:-.05em;line-height:1.1;margin:12px 0 15px}.quiz-length{font-size:14px;color:var(--muted);padding-bottom:17px}.quiz-intro{font-size:16px;line-height:1.6;max-width:760px;color:var(--muted)}.save-hint{font-size:13px;line-height:1.6;color:var(--muted);margin:16px 0 28px}.save-hint button{margin-left:12px;font-size:13px}.game-hud{display:flex;gap:40px;padding:17px 0;border-block:1px solid var(--line);margin:24px 0}.game-hud>div{display:flex;align-items:baseline;gap:10px}.game-hud small{font-size:11px;color:var(--muted);letter-spacing:.02em}.game-hud b{font-size:22px;font-weight:550;letter-spacing:-.035em}.game-hud b span{font-size:11px;font-weight:400;letter-spacing:0;color:var(--muted)}.game-path{display:grid;grid-template-columns:repeat(8,1fr);gap:8px;list-style:none;margin:24px 0;padding:0}.game-path li{position:relative;display:flex;flex-direction:column;align-items:center;gap:7px;text-align:center}.game-path li:not(:last-child)::after{content:'';position:absolute;top:15px;left:calc(50% + 21px);width:calc(100% - 33px);height:1px;background:var(--line)}.game-path span{display:grid;place-items:center;width:32px;height:32px;border:1px solid var(--line);border-radius:50%;font-size:13px;font-weight:500;color:var(--muted)}.game-path small{font-size:11px;color:var(--muted);line-height:1.3}.game-path .current span{background:#0071e3;color:#fff;border-color:#0071e3;box-shadow:0 0 0 4px #0071e30e}.game-path .won span{background:#e5f3eb;border-color:#74a98b;color:#27573b}.game-path .missed span{background:#fbf0e3;border-color:#c7a582;color:#855426}.game-arena{display:grid;grid-template-columns:.8fr 1.2fr;background:var(--panel);border:1px solid var(--line);border-radius:16px;overflow:hidden}.game-visual{position:relative;display:flex;align-items:center;justify-content:center;background:radial-gradient(ellipse at 45% 15%,#243a57,#121d2e);min-width:0}.game-visual svg{display:block;width:100%;height:auto;max-height:320px}.arena-tag{position:absolute;left:22px;bottom:20px;font-size:10px;letter-spacing:.04em;color:#b9c9df}.quiz-stage{padding:27px 28px;min-width:0;animation:questionArrival .25s ease-out}.quiz-status{display:flex;justify-content:space-between;gap:15px;font-size:12px;color:var(--muted)}.quiz-status .eyebrow{font-size:12px;letter-spacing:0;font-weight:400}.quiz-stage h3{font-size:22px;line-height:1.4;letter-spacing:-.025em;font-weight:550;margin:18px 0 22px}.quiz-options{display:grid;gap:10px}.quiz-options button{display:flex;gap:12px;text-align:left;background:var(--bg);padding:13px 15px;font-size:15px;line-height:1.5;transition:background .15s,border-color .15s}.quiz-options button>span{flex-shrink:0;color:var(--muted);font-size:13px;padding-top:2px}.quiz-options button[aria-pressed=true]{background:#e8f2ff;border-color:#0071e3;color:#075296}.quiz-options button:disabled{opacity:1;cursor:default}.quiz-options button.answer-right{border-color:#68a280;background:#e5f4eb;color:#195d3e}.quiz-options button.answer-miss{border-color:#c59671;background:#fbefdf;color:#785329}.quiz-actions{display:flex;gap:12px;justify-content:space-between;margin-top:22px}.quiz-actions button{font-size:14px;padding:10px 16px}.round-feedback{padding:16px;margin-top:18px;border-radius:10px;animation:questionArrival .3s ease-out}.round-feedback strong{font-size:17px;letter-spacing:-.02em}.round-feedback p{font-size:15px;line-height:1.55;color:inherit;margin:9px 0}.round-feedback>span{font-size:12px}.round-win{background:#e3f4eb;color:#205f44}.round-learn{background:#fff0df;color:#744d21}.hint-box{border-left:2px solid #0071e3;padding:10px 14px;margin-top:16px;font-size:14px;line-height:1.55;background:var(--bg);color:var(--muted)}.score-result{padding:28px 0;text-align:center;border-block:1px solid var(--line)}.score-result .eyebrow{font-size:12px;font-weight:400;letter-spacing:.02em}.score-number{font-size:80px;letter-spacing:-.06em;color:var(--ink);font-weight:550}.score-result h3{font-size:25px;margin:10px 0}.score-result button{font-size:14px;margin:4px}.result-list{display:grid;grid-template-columns:1fr 1fr;column-gap:30px}.answer-review{padding:24px 0;border-bottom:1px solid var(--line)}.answer-review h3{font-size:19px;line-height:1.4;letter-spacing:-.025em;margin:8px 0}.answer-review p{font-size:15px;line-height:1.6;margin:10px 0}.result-label{font-size:11px;color:#246c3d}.result-label.miss{color:#90572f}.revisit{font-size:13px;padding:8px 12px}.review-section{padding-top:54px}.review-section>p{font-size:16px;color:var(--muted)}.review-grid{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin:22px 0}.review-card{padding:22px;border:1px solid var(--line);border-radius:12px;background:var(--panel)}.review-card.mastered{border-color:#589a72}.review-card .eyebrow{font-size:12px;letter-spacing:0}.flash-face{display:block;width:100%;min-height:160px;text-align:left;padding:20px;background:var(--bg);margin:16px 0;font:inherit;line-height:1.6;transition:background .2s}.flash-face[aria-pressed=true]{animation:cardTurn .3s ease-out}.flash-face strong{display:block;font-size:11px;font-weight:500;letter-spacing:.03em;color:var(--muted);margin-bottom:12px}.review-card details{font-size:14px;line-height:1.6}.review-card details button{font-size:13px;padding:8px 12px}.review-toolbar{display:flex;justify-content:space-between;align-items:center;gap:10px;margin-top:18px;font-size:12px;color:var(--muted)}.review-toolbar button{font-size:13px}.empty-deck{padding:25px 0;color:var(--muted);font-size:15px}.demo-main footer{padding:28px 0;margin-top:50px;font-size:13px;border-top:1px solid var(--line)}.demo-main footer p{font-size:13px;line-height:1.65}.sr-only{position:absolute;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;clip:rect(0,0,0,0);border:0;white-space:nowrap}
[data-theme=dark] .lab-tabs button.selected{border-color:#71b3ff;color:var(--ink)}[data-theme=dark] .lab-choice-row button[aria-pressed=true],[data-theme=dark] .level-picks button[aria-pressed=true],[data-theme=dark] .quiz-options button[aria-pressed=true]{background:#173557;color:#c2deff;border-color:#71b3ff}[data-theme=dark] .game-path .won span,[data-theme=dark] .round-win,[data-theme=dark] .quiz-options button.answer-right{background:#183d2e;color:#b5e5cd;border-color:#3e775e}[data-theme=dark] .game-path .missed span,[data-theme=dark] .round-learn,[data-theme=dark] .quiz-options button.answer-miss{background:#423220;color:#f0d0aa;border-color:#8f714e}[data-theme=dark] .result-label{color:#93d5a7}[data-theme=dark] .result-label.miss{color:#f4b58e}
@keyframes barReveal{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:translateY(0)}}@keyframes referenceReveal{from{stroke-dashoffset:55;opacity:0}to{stroke-dashoffset:0;opacity:1}}@keyframes sectionArrival{from{opacity:.45;transform:translateY(15px)}to{opacity:1;transform:translateY(0)}}@keyframes questionArrival{from{opacity:.5;transform:translateX(8px)}to{opacity:1;transform:translateX(0)}}@keyframes cardTurn{from{opacity:.5;transform:perspective(800px) rotateY(-7deg)}to{opacity:1;transform:perspective(800px) rotateY(0)}}
@media(max-width:800px){.lab-workspace{grid-template-columns:1fr 1fr}.lab-instructions{padding:22px;min-height:320px}.lab-instructions h3{font-size:21px}.lab-instructions>p{font-size:14px}.lab-chart-key{padding:5px 14px 14px;font-size:10px;gap:10px}.lesson-summary{gap:32px;grid-template-columns:.9fr 1.4fr}.summary-heading h2{font-size:30px}.summary-copy>p{font-size:16px}.game-arena{grid-template-columns:1fr}.game-visual{min-height:210px}.game-visual svg{max-height:230px}.game-hud{gap:24px}.game-hud>div{display:block}.game-hud small{display:block;margin-bottom:3px}}
@media(max-width:600px){.demo-main{padding:0 20px 40px}.demo-page header{padding:0 20px;height:62px;gap:12px}.demo-page header .home-nav{display:none}.lesson-opening{padding:42px 0 30px}.demo-main .lesson-opening h1{font-size:52px;line-height:1.01}.lesson-intro{font-size:18px;line-height:1.55}.lesson-index{font-size:13px;margin-bottom:22px}.lesson-meta{flex-wrap:wrap;gap:12px 18px;font-size:12px;margin-top:24px}.lesson-meta a{margin-left:0}.lab-heading{padding-top:20px}.lab-heading h2{font-size:23px}.section-number{font-size:12px}.lab-tabs{margin-bottom:12px}.lab-tabs button{flex:none;padding:12px 13px;font-size:13px}.lab-workspace{grid-template-columns:1fr;border-radius:12px}.lab-visual svg{max-height:230px;min-height:200px}.lab-chart-key{justify-content:center}.lab-instructions{min-height:0;padding:23px}.lab-instructions h3{font-size:23px}.lab-instructions>p{font-size:16px}.lab-bottom{flex-wrap:wrap;font-size:12px;gap:12px}.lab-bottom>span{display:none}.lab-bottom .primary{margin-left:auto}.lesson-summary{display:block;padding:40px 0;margin-top:12px}.summary-heading{margin-bottom:26px}.summary-heading h2{font-size:34px;margin:10px 0 16px}.summary-heading h2 br{display:none}.summary-heading>p{max-width:none;font-size:16px}.summary-copy>p{font-size:16px;line-height:1.75;margin-bottom:22px}.worked-note{margin-top:28px;padding-left:18px}.worked-note blockquote{font-size:19px}.demo-quiz{padding-top:38px}.section-top{align-items:start}.section-top h2{font-size:30px}.quiz-length{display:none}.quiz-intro{font-size:15px}.game-hud{justify-content:space-between;gap:10px}.game-hud small{font-size:10px}.game-hud b{font-size:22px}.game-hud b span{font-size:10px}.game-path{gap:2px}.game-path small{display:none}.game-path span{width:28px;height:28px;font-size:12px}.game-path li:not(:last-child)::after{top:13px;left:calc(50% + 16px);width:calc(100% - 25px)}.game-visual{min-height:190px}.game-visual svg{max-height:205px}.arena-tag{left:15px;bottom:12px;font-size:9px}.quiz-stage{padding:23px 18px}.quiz-stage h3{font-size:21px}.quiz-options button{font-size:16px;padding:13px}.quiz-actions button{font-size:13px;padding:10px 13px}.result-list,.review-grid{grid-template-columns:1fr}.review-section{padding-top:38px}.score-number{font-size:68px}}
@media(prefers-reduced-motion:reduce){.demo-page *,.demo-page *::before,.demo-page *::after{animation:none!important;transition:none!important;scroll-behavior:auto!important}}