:root{color-scheme:dark;--bg:#15191b;--surface:#1d2225;--border:#343a3e;--ink:#f6f7f5;--muted:#a9b0b1;--accent:#f0c35b;--success:#92d9ac;--error:#ffb0a0;font-family:Inter,"Segoe UI",Arial,sans-serif;font-synthesis:none}
*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font-size:16px}button,a{-webkit-tap-highlight-color:transparent}button{font:inherit;cursor:pointer}button:disabled{cursor:wait;opacity:.55}button:focus-visible,a:focus-visible{outline:3px solid var(--accent);outline-offset:5px}button{color:inherit}button:hover{filter:brightness(1.1)}[hidden]{display:none!important}.topbar{height:100px;padding:0 36px;display:flex;align-items:center;border-bottom:1px solid var(--border);justify-content:space-between;gap:24px}.brand{display:flex;align-items:center;gap:12px;color:var(--ink);text-decoration:none;font-size:21px;font-weight:800;letter-spacing:-.7px;white-space:nowrap}.brand-mark{width:43px;height:46px;background:var(--accent);border-radius:10px;display:grid;place-items:center;font-size:39px;color:#1c2224;font-weight:400}.brand-light{font-weight:400;margin-left:3px}.brand small{display:block;font-size:10px;letter-spacing:2px;font-weight:500;color:var(--muted);margin-top:5px}.header-center{font-size:11px;font-weight:600;letter-spacing:1.5px;color:var(--muted);display:flex;align-items:center;gap:12px}.line-dot{display:inline-block;width:6px;height:6px;border-radius:50%;background:var(--accent)}.divider{color:#555e61;padding:0 5px}.header-actions{display:flex;gap:9px;align-items:center}.icon-button{background:transparent;border:1px solid var(--border);border-radius:10px;width:41px;height:41px;display:grid;place-items:center}.icon-button svg{width:19px;height:19px;fill:none;stroke:currentColor;stroke-width:1.7}.vr-button{border:1px solid #65634f;color:var(--accent);background:#272820;border-radius:9px;padding:12px 17px;font-size:14px;font-weight:600;display:flex;gap:22px;align-items:center}.vr-button span{font-size:19px}main{display:grid;grid-template-columns:300px minmax(0,1fr);max-width:1800px;margin:auto;min-height:calc(100vh - 151px)}.sidebar{padding:36px 30px 24px;border-right:1px solid var(--border);display:flex;flex-direction:column}.eyebrow,.small-label{font-size:11px;font-weight:600;letter-spacing:1.55px;color:var(--accent)}.eyebrow{display:flex;justify-content:space-between;color:var(--muted);font-size:10px}.eyebrow span{color:#6f797d;letter-spacing:0}#lesson-heading h1{font-size:37px;line-height:1.14;letter-spacing:-1.4px;font-weight:500;margin:28px 0 16px}#lesson-heading h1 em{font-style:normal;color:var(--accent)}#lesson-heading p{font-size:14px;line-height:1.7;color:var(--muted);max-width:230px}.steps{margin-top:37px;display:flex;flex-direction:column;gap:5px}.step{display:flex;gap:13px;position:relative;align-items:center;min-height:67px;padding:9px 10px;border-radius:11px}.step-number{border:1px solid #424b4f;border-radius:50%;width:31px;height:31px;display:grid;place-items:center;font-size:11px;flex-shrink:0;color:#a9b0b1}.step-name{display:block;font-size:14px;color:var(--muted);font-weight:500}.step-desc{font-size:11px;color:#909b9f;display:block;margin-top:4px}.step.active{background:#292b24}.step.active .step-name{color:var(--ink)}.step.active .step-number{background:var(--accent);border-color:var(--accent);color:#15191b}.step.completed .step-number{color:var(--success);border-color:#49765c}.sidebar-bottom{margin-top:auto;padding-top:35px}.sidebar-bottom .small-label{color:#8e999d;font-size:10px}.sidebar-bottom p{font-size:14px;line-height:1.85;color:#b5bcbc}.session-note{border-top:1px solid var(--border);padding-top:18px;display:flex;gap:9px;font-size:12px;color:#939fa2}.workspace{padding:24px;min-width:0;display:flex;flex-direction:column}.scene-wrap{position:relative;min-height:320px;height:clamp(320px,48vh,600px);border-radius:15px;overflow:hidden;background:#b9c3c9;isolation:isolate}.scene-wrap:after{content:"";pointer-events:none;position:absolute;inset:0;background:linear-gradient(180deg,rgba(17,28,31,.25),transparent 30%,transparent 73%,rgba(17,28,31,.52));z-index:1}#scene{position:absolute;inset:0}#scene canvas{width:100%;height:100%;display:block;touch-action:pan-y}.scene-top{position:absolute;top:20px;left:22px;right:22px;display:flex;align-items:center;justify-content:space-between;z-index:2;gap:10px;pointer-events:none}.location-chip{background:#20282bdd;color:#f0f2f0;backdrop-filter:blur(8px);border:1px solid #ffffff20;padding:10px 12px;border-radius:6px;display:flex;align-items:center;gap:9px;font-size:10px;letter-spacing:1px;font-weight:600}.chip-rule{height:10px;width:1px;background:#78868a}.view-chip{font-size:10px;letter-spacing:1px;border:1px solid #ffffff60;padding:8px 10px;border-radius:5px;color:#fff;background:#27323648}.scene-caption{position:absolute;left:26px;bottom:48px;z-index:2;max-width:420px;pointer-events:none}.scene-caption .scene-kicker{font-size:10px;letter-spacing:1.7px;color:#fff;display:block;margin-bottom:8px}.scene-caption h2{font-weight:500;font-size:34px;line-height:1.12;letter-spacing:-1px;margin:0;text-shadow:0 2px 16px #14212488}.scene-caption p{font-size:13px;line-height:1.5;max-width:370px;color:#e3e8e5;margin:8px 0}.scene-footer{position:absolute;left:24px;right:24px;bottom:17px;z-index:2;display:flex;justify-content:space-between;font-size:11px;color:#e7edeb}.scene-footer kbd{font-family:inherit;border:1px solid #ffffff60;padding:2px 5px;border-radius:3px;margin-right:5px}.interaction{padding:25px 2px 0}.interaction-heading{display:flex;justify-content:space-between;align-items:flex-start;gap:12px}.interaction h2{font-size:23px;font-weight:500;letter-spacing:-.5px;margin:8px 0 0;line-height:1.3}.text-button{background:none;border:0;color:#bec6c8;font-size:12px;white-space:nowrap;padding:10px 0}.text-button span{font-size:18px;margin-left:9px}.instruction{font-size:14px;color:var(--muted);line-height:1.6;margin:10px 0 18px;max-width:800px}.options{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}.option{display:flex;align-items:center;gap:14px;text-align:left;position:relative;background:#22272a;border:1px solid #40474b;border-radius:10px;padding:17px 15px;min-height:84px;transition:background .18s,border-color .18s,transform .18s}.option:hover{background:#2e332c;border-color:var(--accent);transform:translateY(-2px)}.option-icon{width:39px;height:39px;background:#32393c;border-radius:9px;display:grid;place-items:center;flex-shrink:0;color:var(--accent)}.option-icon svg{height:23px;width:23px;fill:none;stroke:currentColor;stroke-width:1.5;stroke-linecap:round;stroke-linejoin:round}.option strong{display:block;font-size:14px;font-weight:500;line-height:1.4}.option small{display:block;color:#a6afb3;margin-top:4px;font-size:11px;line-height:1.45}.option-arrow{margin-left:auto;color:#a8b2b5;font-size:18px}.option.primary{background:var(--accent);color:#20241f;border-color:var(--accent)}.option.primary .option-icon{background:#d6aa46;color:#20241f}.option.primary .option-arrow,.option.primary small{color:#343d33}.options.single{grid-template-columns:minmax(0,370px)}.options.two{grid-template-columns:repeat(2,minmax(0,1fr))}.bottom-note{margin-top:16px;color:#a0aaae;font-size:11px;line-height:1.55}.bottom-note .keyboard-hint{float:right}#feedback{padding:12px 15px;border-radius:8px;margin-bottom:14px;font-size:14px;line-height:1.6;border-left:3px solid var(--accent);background:#2e3025;color:#f2dcaa}#feedback.good{background:#1e322b;border-color:var(--success);color:#b4ebc9}#feedback.bad{background:#342a25;border-color:var(--error);color:#ffd2c1}.stats{display:flex;gap:9px;margin-left:auto}.stats span{background:#20282bef;padding:9px 12px;border-radius:6px;font-variant-numeric:tabular-nums;font-size:14px;color:#fff}.stats #timer{color:var(--accent)}.app-footer{display:flex;justify-content:space-between;border-top:1px solid var(--border);padding:18px 35px;color:#95a0a4;font-size:10px;letter-spacing:1.2px;gap:20px}.footer-slash{padding:0 10px;color:#515b60}dialog{color:var(--ink);background:var(--surface);border:1px solid #566064;border-radius:20px;width:min(460px,calc(100% - 36px));padding:36px;box-shadow:0 20px 100px #0008}dialog::backdrop{background:#090e12bb;backdrop-filter:blur(7px)}dialog h2{font-size:28px;font-weight:500;letter-spacing:-1px}dialog p{line-height:1.7;color:var(--muted);font-size:15px}.dialog-icon{font-size:34px;color:var(--accent);margin-bottom:20px}.primary-button{background:var(--accent);border:0;border-radius:8px;padding:15px 22px;color:#1c2220;font-weight:600;margin-top:12px;width:100%}.scene-error{position:absolute;inset:0;display:grid;align-content:center;text-align:center;padding:45px;background:#273237;z-index:4;line-height:1.7}.result-tally{color:var(--accent);font-size:64px;letter-spacing:-3px}.review-list{margin:0 0 14px;padding-left:20px;line-height:1.7}.vr-active .scene-wrap{background:#15191b}@media(min-width:1600px){main{grid-template-columns:335px minmax(0,1fr)}.sidebar{padding:44px 37px}.workspace{padding:30px}.scene-wrap{height:55vh}}@media(max-width:1100px){.header-center{display:none}main{grid-template-columns:255px minmax(0,1fr)}.topbar{padding:0 24px}.sidebar{padding:28px 22px}.workspace{padding:20px}#lesson-heading h1{font-size:32px}.option{padding:13px 10px;gap:9px}.option-icon{width:32px;height:34px}.option small{display:none}.option-arrow{display:none}.scene-caption h2{font-size:29px}.scene-wrap{height:43vh}.text-button{font-size:11px}}@media(max-width:760px){.topbar{height:78px;padding:0 17px;gap:10px}.brand{font-size:17px;gap:8px}.brand-mark{width:34px;height:37px;font-size:30px}.brand small{font-size:8px;letter-spacing:1px}.header-actions{gap:6px}.icon-button{width:33px;height:35px}.vr-button{padding:10px;font-size:12px;gap:6px}.vr-button span{display:none}main{display:flex;flex-direction:column}.sidebar{border-right:0;padding:19px 18px 0}.eyebrow,.sidebar-bottom,#lesson-heading{display:none}.steps{margin:0;flex-direction:row;gap:4px;justify-content:space-between}.step{padding:8px 7px;min-height:49px;gap:6px}.step-number{width:25px;height:25px;font-size:10px}.step-name{font-size:11px}.step-desc{display:none}.workspace{padding:14px 16px 24px}.scene-wrap{height:360px;min-height:280px}.scene-top{top:14px;left:13px;right:13px}.view-chip{display:none}.location-chip{font-size:9px;padding:9px;gap:7px}.scene-caption{left:18px;bottom:47px}.scene-caption h2{font-size:30px}.scene-footer{left:17px;right:17px;font-size:10px}.scene-footer span:last-child{display:none}.interaction{padding-top:23px}.interaction h2{font-size:22px}.text-button{font-size:0}.text-button span{font-size:23px}.options{gap:9px}.option{min-height:85px;flex-direction:column;align-items:flex-start;padding:13px 11px;gap:9px}.option strong{font-size:12px}.option.primary{flex-direction:row;align-items:center;min-height:68px}.option.primary strong{font-size:14px}.option.primary .option-arrow{display:block}.options.single{grid-template-columns:1fr}.instruction{font-size:14px}.app-footer{font-size:9px;padding:15px 17px;letter-spacing:.5px}.app-footer>span:last-child{display:none}.bottom-note .keyboard-hint{display:none}.stats{gap:5px}.stats span{padding:8px;font-size:12px}.scene-caption p{max-width:290px}.step.active .step-name{color:#fff}}@media(prefers-reduced-motion:reduce){*,*:before,*:after{transition:none!important;scroll-behavior:auto!important}}@media(max-width:380px){.brand small{display:none}.brand{font-size:14px}.brand-mark{width:29px;height:32px}.step{padding:6px 4px}.step-name{font-size:10px}.scene-wrap{height:300px}.location-chip{font-size:8px}.app-footer{font-size:8px}}