:root{color-scheme:dark;--ink:#071a36;--muted:#8190a7;--mint:#bde1d6;--paper:#f5f7f8;--line:#dfe5e8;--sidebar:300px;font-family:Inter,"Segoe UI",Arial,sans-serif;font-synthesis:none}
*{box-sizing:border-box}body{margin:0;background:var(--ink);color:#fff}button,input,select{font:inherit}button,a,input,select{-webkit-tap-highlight-color:transparent}button{cursor:pointer}button:disabled{opacity:.35;cursor:default}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid #73baaa;outline-offset:4px}button{border:0}a{color:inherit}[hidden]{display:none!important}.topbar{height:70px;display:flex;align-items:center;padding:0 30px;border-bottom:1px solid #ffffff14;gap:24px}.brand{font-size:36px;letter-spacing:-2px;font-weight:800;text-decoration:none;line-height:1}.brand span{font-size:10px;letter-spacing:0;vertical-align:top;display:inline-block;margin:5px}.top-divider{height:20px;width:1px;background:#ffffff30}.top-label{font-size:10px;letter-spacing:2.5px;color:#c0cada}.top-right{margin-left:auto;display:flex;align-items:center;gap:16px;font-size:12px;color:#b4c1d4}.layout{display:grid;grid-template-columns:var(--sidebar) 1fr;height:calc(100dvh - 70px)}.sidebar{background:var(--paper);color:var(--ink);display:flex;flex-direction:column;min-height:0;padding:28px 0 18px;border-right:1px solid var(--line)}.sidebar-heading,.sidebar-intro,.course-progress{margin-left:25px;margin-right:25px}.sidebar-heading{display:flex;justify-content:space-between;align-items:start}.eyebrow{font-size:10px;letter-spacing:1.8px;font-weight:650;margin:0 0 12px;color:var(--muted)}h1{font-size:27px;line-height:1.18;letter-spacing:-1px;margin:0} .sidebar-intro{font-size:12px;line-height:1.8;color:#6b7585;margin-top:16px;margin-bottom:23px}.course-progress{margin-bottom:22px;font-size:10px;font-weight:600;color:#637080}.course-progress>div{display:flex;justify-content:space-between;margin-bottom:7px}progress{display:block;width:100%;height:4px;border:0;accent-color:#408b79;border-radius:4px;overflow:hidden}progress::-webkit-progress-bar{background:#e0e7e7}progress::-webkit-progress-value{background:#408b79}#chapters{overflow:auto;overscroll-behavior:contain;flex:1;scrollbar-width:thin;scrollbar-color:#c9d4d7 transparent;padding:0 14px}.chapter{margin-bottom:5px}.chapter summary{list-style:none;cursor:pointer;display:flex;align-items:center;gap:12px;padding:13px 10px;font-size:12px;font-weight:600;border-radius:8px;line-height:1.4}.chapter summary::-webkit-details-marker{display:none}.chapter summary:hover{background:#e9eff0}.chapter-number{font-size:11px;color:#8a97a5;font-variant-numeric:tabular-nums;align-self:flex-start;padding-top:2px}.chapter summary:after{content:'+';margin-left:auto;color:#8a97a5}.chapter[open] summary:after{content:'−'}.lesson-link{width:100%;background:transparent;color:#6b7785;display:flex;text-align:left;align-items:center;gap:10px;padding:11px 12px 11px 35px;font-size:11px;line-height:1.5;border-radius:7px}.lesson-link:hover{background:#e8eeee}.lesson-link[aria-current=true]{background:#dfece7;color:#123b30;font-weight:650}.lesson-link .lesson-indicator{flex:0 0 15px;font-size:11px}.lesson-link .lesson-name{flex:1}.lesson-link .duration{color:#899b97;font-size:10px;font-variant-numeric:tabular-nums}.sidebar-bottom{padding:18px 24px 0;display:flex;gap:8px;font-size:10px;color:#81908c;line-height:1.5}.save-dot{width:5px;height:5px;flex-shrink:0;background:#6fa18d;border-radius:50%;margin-top:5px}.workspace{min-width:0;min-height:0;display:flex;flex-direction:column;padding:24px 36px 10px;background:radial-gradient(ellipse at 45% 35%,#163253 0%,#091d39 48%,#071a36 100%)}.lesson-heading{display:flex;justify-content:space-between;max-width:900px;width:100%;margin:0 auto 17px;font-size:9px;letter-spacing:1.8px;color:#8f9fb7;flex-shrink:0}.view-layout{display:flex;align-items:center;justify-content:center;gap:clamp(24px,5vw,80px);min-height:0;flex:1}.player-column{width:min(100%,390px);height:100%;display:flex;flex-direction:column;min-height:0;flex-shrink:1}.stage{position:relative;flex:1;min-height:0;isolation:isolate;border-radius:12px;overflow:hidden;background:#041329;box-shadow:0 15px 60px #0003}.swiper{height:100%;width:100%}.swiper-slide{display:flex;align-items:center;justify-content:center;overflow:hidden}.swiper-slide video{height:100%;width:100%;object-fit:contain;display:block;background:#041329}.welcome{position:absolute;inset:0;z-index:3;background:#071a36e8;display:flex;align-items:center;justify-content:center;padding:24px}.welcome-card{text-align:center}.welcome-mark{display:block;color:var(--mint);font-size:64px;font-weight:850;letter-spacing:-6px;margin-bottom:24px}.welcome-card .eyebrow{color:#97baaf}.welcome-card h2{font-size:26px;line-height:1.25;letter-spacing:-.8px}.welcome-card p:not(.eyebrow){font-size:12px;color:#aab8cd;line-height:1.9}.primary{background:var(--mint);color:#102f29;padding:14px 23px;border-radius:8px;font-size:12px;font-weight:700;min-height:44px}.primary:hover{background:#d6f2e9}.welcome-card .primary{margin-top:17px;min-width:210px}.welcome-hint{display:block;font-size:10px;color:#899db7;margin-top:15px}.player-footer{padding-top:14px;flex-shrink:0}.caption-heading{display:flex;align-items:center;gap:8px}.caption-heading h2{font-size:13px;line-height:1.4;margin:0;flex:1;font-weight:550;min-height:18px}.caption-heading .icon-btn{height:28px;width:28px;color:#95a7be;flex-shrink:0}.scrub-row{display:flex;align-items:center;gap:12px;margin:6px 0 4px}.scrub-row input{min-width:0;flex:1;accent-color:var(--mint);height:18px;cursor:pointer}.scrub-row #time{font-size:10px;color:#93a4bc;font-variant-numeric:tabular-nums}.controls{display:flex;gap:5px;align-items:center;min-height:43px}.icon-btn,.play-btn{display:inline-flex;justify-content:center;align-items:center;position:relative;color:inherit;background:transparent;width:40px;height:40px;border-radius:8px;flex-shrink:0}.icon-btn:hover{background:#ffffff13}.icon-btn svg,.play-btn svg{width:19px;height:19px}.icon-btn small{font-size:9px;position:absolute;bottom:8px;right:9px}#rewind{font-size:27px;padding-bottom:5px}.play-btn{background:#ffffff14;border:1px solid #ffffff12;margin:0 4px}.control-spacer{flex:1}select{color:#b6c6d9;background:#102744;border:0;padding:8px 2px;font-size:11px;border-radius:7px;width:57px}.swipe-hint{font-size:10px;color:#7187a3;text-align:center;margin:11px 0 0;flex-shrink:0}.lesson-notes{width:245px;flex-shrink:0;padding-bottom:45px}.role{display:inline-block;color:var(--mint);font-size:10px;border:1px solid #6b9c8f55;padding:6px 10px;border-radius:5px;margin-bottom:28px}.lesson-notes .eyebrow{font-size:9px;line-height:1.7}.lesson-notes h2{font-size:28px;line-height:1.25;letter-spacing:-.7px;font-weight:550;margin:0 0 20px}.lesson-notes #context{font-size:12px;color:#a6b5ca;line-height:1.9}.notes-divider{height:1px;background:#ffffff15;margin:27px 0 15px}.notes-link{background:transparent;color:#bdcddd;font-size:11px;width:100%;text-align:left;padding:13px 0;display:flex;justify-content:space-between;gap:12px}.notes-link:hover{color:white}.notes-help{font-size:10px;line-height:1.8;color:#7087a1;margin-top:25px}.end-card,.video-error{position:absolute;inset:auto 16px 16px;z-index:2;background:#0b233df5;padding:23px;border:1px solid #ffffff25;border-radius:10px;text-align:center;box-shadow:0 4px 30px #0005}.end-card h2{font-size:18px;line-height:1.5}.end-card .eyebrow{color:var(--mint)}.end-card .primary{width:100%;margin:6px 0}.text-button{display:block;background:transparent;color:#c0d1e2;font-size:11px;margin:10px auto 0;padding:8px}.video-error{font-size:12px;line-height:1.6}dialog{color:var(--ink);color-scheme:light;background:var(--paper);width:min(580px,calc(100% - 28px));max-height:85dvh;border:0;border-radius:14px;padding:30px;box-shadow:0 30px 90px #0006}dialog::backdrop{background:#03152bcc;backdrop-filter:blur(5px)}.dialog-header{display:flex;justify-content:space-between;align-items:center}.dialog-header .eyebrow{margin:0}dialog h2{font-size:25px;letter-spacing:-.6px}#transcript-context{font-size:12px;color:#738276;border-left:3px solid #a3cabc;padding-left:12px;line-height:1.7}#transcript-body p{font-size:14px;line-height:1.9;color:#37485e}dialog>.primary{margin-top:15px}dialog .icon-btn:hover{background:#dde5e6}.notice{position:fixed;bottom:24px;left:50%;transform:translateX(-50%);z-index:20;background:#d3ece3;color:#173e30;font-size:12px;padding:13px 22px;border-radius:9px;box-shadow:0 5px 30px #0004;text-align:center}.mobile-menu{display:none}.skip-link{position:fixed;left:10px;top:-50px;z-index:40;background:white;color:var(--ink);padding:12px}.skip-link:focus{top:10px}.fatal{position:fixed;inset:30%;z-index:40;background:#fff;color:var(--ink);padding:30px}
@media(min-width:1500px){.player-column{width:430px}.lesson-notes{width:290px}.workspace{padding-top:30px}.lesson-notes h2{font-size:34px}}
@media(max-width:1150px){:root{--sidebar:265px}.workspace{padding:20px}.lesson-notes{display:none}.player-column{max-width:420px}.view-layout{gap:0}.sidebar-heading,.sidebar-intro,.course-progress{margin-left:20px;margin-right:20px}}
@media(max-width:760px){.topbar{height:54px;padding:0 17px;gap:15px}.brand{font-size:29px}.brand span{font-size:8px}.top-label{font-size:9px}.top-right{font-size:10px;gap:8px}.layout{display:block;height:calc(100dvh - 54px)}.mobile-menu{display:inline-flex}.sidebar{display:none;position:fixed;inset:0 auto 0 0;width:min(340px,88vw);z-index:12;padding-top:27px;box-shadow:10px 0 40px #0005}.sidebar.open{display:flex}.sidebar-backdrop{position:fixed;inset:0;background:#0009;z-index:11;backdrop-filter:blur(3px)}.sidebar .icon-btn{color:var(--ink)}.workspace{height:100%;padding:11px 12px max(8px,env(safe-area-inset-bottom))}.lesson-heading{font-size:8px;letter-spacing:1.2px;margin-bottom:9px;max-width:460px}.player-column{max-width:460px;width:100%}.stage{border-radius:8px;box-shadow:none}.player-footer{padding:8px 4px 0}.caption-heading h2{font-size:12px;line-height:1.35;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}.controls{gap:10px}.controls .icon-btn,.play-btn{height:40px}.swipe-hint{margin-top:5px;font-size:9px}.swipe-hint span{display:none}.welcome{padding:15px}.welcome-mark{font-size:47px;margin-bottom:15px}.welcome-card h2{font-size:23px}.welcome-card .primary{margin-top:10px}.welcome-card .eyebrow{font-size:9px}.welcome-card p:not(.eyebrow){font-size:11px}.welcome-hint{font-size:9px}.notice{width:max-content;max-width:90%;bottom:15px}.sidebar-intro{margin-bottom:15px}.sidebar-bottom{font-size:10px}}
@media(max-height:640px){.welcome-mark{display:none}.welcome-card h2{font-size:20px;margin:10px 0}.welcome-card .eyebrow{margin:0}.welcome-card p:not(.eyebrow){line-height:1.6}.welcome-hint{display:none}.swipe-hint{display:none}.lesson-heading{margin-bottom:8px}.workspace{padding-top:10px}}
.restart-course{background:transparent;color:#637b72;font-size:11px;text-align:left;padding:15px 25px 0}.restart-course:hover{text-decoration:underline}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{scroll-behavior:auto!important;transition-duration:0ms!important;animation:none!important}}