:root{--canvas:#07090d;--panel:#10141b;--panel2:#171c25;--line:#2a303b;--text:#f7f5ee;--muted:#9ba3b2;--gold:#c9a84c;--gold2:#9a7c1e;--light:#f7f3eb;--ink:#1b2238;--good:#58b98c;--shadow:0 26px 80px rgba(0,0,0,.45);font-family:'Sora',system-ui,-apple-system,'Segoe UI',sans-serif;color-scheme:dark}
*{box-sizing:border-box}html,body{height:100%;margin:0;background:var(--canvas);color:var(--text);overflow:hidden}button{font:inherit}.viewer{height:100dvh;display:grid;grid-template-rows:64px minmax(0,1fr) 68px;background:radial-gradient(circle at 50% 45%,#161b23 0,#090c11 55%,#05070a 100%)}
.topbar{display:flex;align-items:center;justify-content:space-between;gap:18px;padding:0 22px;border-bottom:1px solid rgba(255,255,255,.09);background:rgba(7,9,13,.92);z-index:5}.identity{display:flex;align-items:center;gap:12px;color:var(--text);text-decoration:none;min-width:0}.identity-mark{display:grid;place-items:center;width:34px;height:34px;border:1px solid rgba(201,168,76,.5);border-radius:10px;color:var(--gold);font-family:Georgia,serif;font-size:23px;font-weight:700}.identity strong,.identity small{display:block;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.identity strong{font-size:13px}.identity small{font-size:11px;color:var(--muted);margin-top:2px}.top-actions{display:flex;align-items:center;gap:7px}.icon-button,.tools-button{height:38px;border:1px solid transparent;border-radius:9px;background:transparent;color:var(--text);cursor:pointer;display:inline-flex;align-items:center;justify-content:center}.icon-button{width:38px}.icon-button:hover,.tools-button:hover{background:var(--panel2);border-color:var(--line)}.icon-button:focus-visible,.tools-button:focus-visible,.nav-button:focus-visible,.counter:focus-visible{outline:2px solid var(--gold);outline-offset:2px}.icon-button svg,.tools-button svg,.nav-button svg{width:20px;height:20px;fill:currentColor}.tools-button{gap:8px;padding:0 11px;font-size:12px;font-weight:600}.tools-count{background:var(--gold);color:#151109;border-radius:999px;padding:2px 6px;font-size:10px;font-variant-numeric:tabular-nums}
.stage{position:relative;min-height:0;display:grid;place-items:center;padding:18px 72px}.slide-frame{position:relative;margin:0;height:100%;width:100%;display:grid;place-items:center}.slide-frame img{display:block;max-width:100%;max-height:100%;aspect-ratio:16/9;object-fit:contain;background:#050505;box-shadow:0 28px 85px rgba(0,0,0,.5);user-select:none}.edge{position:absolute;top:0;bottom:0;width:9%;border:0;background:transparent;cursor:pointer;z-index:2}.edge:disabled{cursor:default}.edge-previous{left:0}.edge-next{right:0}.slide-resource{position:absolute;z-index:4;right:max(12px,calc((100% - (100vh - 168px) * 16 / 9)/2 + 18px));bottom:16px;display:flex;flex-direction:column;align-items:flex-start;gap:2px;max-width:min(430px,48%);padding:11px 16px;border:1px solid #e9c764;border-radius:12px;background:#c9a84c;color:#151109;text-align:left;box-shadow:0 12px 34px rgba(0,0,0,.38);cursor:pointer}.slide-resource[hidden]{display:none}.slide-resource:hover{background:#dfbf5c;transform:translateY(-1px)}.slide-resource span{font-size:9px;font-weight:800;letter-spacing:.1em;text-transform:uppercase}.slide-resource strong{font-size:13px;line-height:1.25}.slide-resource.done{border-color:#75c8a1;background:#183a2f;color:#d9ffec}.slide-resource.done span{color:#8ce1b9}
.controls{position:relative;display:grid;grid-template-columns:1fr auto 1fr;align-items:center;padding:0 22px;border-top:1px solid rgba(255,255,255,.09);background:rgba(7,9,13,.94)}.progress-track{position:absolute;left:0;right:0;top:0;height:2px;background:rgba(255,255,255,.08)}.progress-track span{display:block;height:100%;width:0;background:var(--gold);transition:width .2s ease}.nav-button{border:0;background:transparent;color:var(--muted);display:flex;align-items:center;gap:7px;padding:10px 6px;cursor:pointer;font-size:12px;font-weight:600}.nav-button:hover{color:var(--text)}.nav-button:disabled{opacity:.25;cursor:default}.nav-button:last-child{justify-self:end}.counter{border:0;background:transparent;color:var(--muted);cursor:pointer;display:flex;align-items:baseline;gap:7px;padding:10px 14px}.counter strong{color:var(--text);font-size:15px;font-variant-numeric:tabular-nums}.counter span{font-size:12px;font-variant-numeric:tabular-nums}
dialog{color:var(--text)}dialog::backdrop{background:rgba(0,0,0,.74);backdrop-filter:blur(7px)}.modal{width:min(1100px,94vw);max-height:90vh;border:1px solid var(--line);border-radius:18px;background:var(--panel);box-shadow:var(--shadow);padding:22px}.modal-heading,.exercise-heading{display:flex;justify-content:space-between;gap:20px;align-items:flex-start}.modal-heading h2,.exercise-heading h2{margin:2px 0 0;font-size:26px;letter-spacing:-.03em}.modal-heading p,.exercise-heading p{color:var(--muted);font-size:13px;margin:7px 0 0;max-width:70ch}.modal-kicker{font-size:10px;text-transform:uppercase;letter-spacing:.12em;color:var(--gold);font-weight:700}.close-button{border:1px solid var(--line);background:var(--panel2);color:var(--text);width:36px;height:36px;border-radius:9px;font-size:23px;line-height:1;cursor:pointer;flex:none}.close-button:hover{border-color:var(--gold)}
.overview-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px;margin-top:22px;max-height:calc(90vh - 105px);overflow:auto;padding-right:4px}.thumb{position:relative;border:1px solid var(--line);border-radius:10px;overflow:hidden;background:#080a0e;padding:0;cursor:pointer}.thumb:hover,.thumb[aria-current="true"]{border-color:var(--gold);box-shadow:0 0 0 1px var(--gold)}.thumb img{display:block;width:100%;aspect-ratio:16/9;object-fit:cover}.thumb span{position:absolute;right:6px;bottom:6px;background:rgba(0,0,0,.8);color:#fff;border-radius:5px;padding:2px 6px;font-size:10px}.thumb i{position:absolute;left:6px;bottom:6px;width:8px;height:8px;border-radius:50%;background:var(--gold);box-shadow:0 0 0 3px rgba(0,0,0,.65)}
.exercise-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin:22px 0}.exercise-card{display:grid;grid-template-columns:36px 1fr auto;align-items:center;gap:12px;text-align:left;border:1px solid var(--line);border-radius:12px;background:var(--panel2);color:var(--text);padding:13px;cursor:pointer}.exercise-card:hover{border-color:var(--gold)}.exercise-number{display:grid;place-items:center;width:36px;height:36px;border-radius:10px;background:rgba(201,168,76,.12);color:var(--gold);font-weight:700}.exercise-copy strong,.exercise-copy small{display:block}.exercise-copy strong{font-size:13px}.exercise-copy small{color:var(--muted);font-size:11px;margin-top:3px}.exercise-status{font-size:10px;color:var(--muted);white-space:nowrap}.exercise-card.done .exercise-status{color:var(--good)}.reset-button{border:0;background:transparent;color:var(--muted);text-decoration:underline;cursor:pointer;font-size:11px;padding:4px 0}
.exercise-modal{width:min(1240px,97vw);height:min(900px,96vh);border:0;border-radius:18px;background:transparent;padding:0;box-shadow:var(--shadow)}.exercise-shell{height:100%;display:grid;grid-template-rows:auto minmax(0,1fr) auto;background:var(--light);color:var(--ink);border-radius:18px;overflow:hidden}.exercise-heading{padding:15px 18px;background:#111725;color:#fff}.exercise-heading h2{font-size:20px}.exercise-heading p{font-size:11px;margin-top:4px}.exercise-frame-wrap{min-height:0;background:var(--light)}.exercise-frame-wrap iframe{display:block;width:100%;height:100%;border:0;background:var(--light)}.exercise-actions{display:flex;justify-content:flex-end;gap:10px;padding:12px 16px;background:#fff;border-top:1px solid #e4ddcf}.primary-action,.secondary-action{border-radius:999px;padding:10px 16px;font-size:12px;font-weight:700;cursor:pointer}.primary-action{border:1px solid var(--gold2);background:var(--gold2);color:#fff}.secondary-action{border:1px solid #cbc5b9;background:#fff;color:var(--ink)}
.shortcuts{margin-top:20px}.shortcuts p{display:grid;grid-template-columns:150px 1fr;align-items:center;gap:18px;margin:0;padding:11px 0;border-top:1px solid var(--line);font-size:13px;color:var(--muted)}kbd{display:inline-block;background:var(--panel2);border:1px solid var(--line);border-bottom-width:2px;border-radius:6px;padding:3px 7px;color:var(--text);font:600 11px 'Sora',sans-serif}
@media(max-width:820px){.viewer{grid-template-rows:56px minmax(0,1fr) 62px}.topbar{padding:0 10px}.identity small,.tools-button>span:not(.tools-count){display:none}.stage{padding:8px 14px}.edge{width:14%}.slide-resource{right:8px;bottom:8px;max-width:76%;padding:9px 12px}.slide-resource strong{font-size:11px}.controls{padding:0 10px}.nav-button span{display:none}.overview-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.exercise-list{grid-template-columns:1fr}.modal{padding:16px}.exercise-modal{width:100vw;height:100dvh;max-width:none;max-height:none;border-radius:0}.exercise-shell{border-radius:0}.exercise-heading{padding:11px 12px}.exercise-actions{padding:9px 10px}.primary-action,.secondary-action{padding:9px 12px}}
@media(prefers-reduced-motion:reduce){*{transition:none!important}}