.lesson-page{grid-template-columns:minmax(260px,340px) 1fr;align-items:start;gap:clamp(20px,3.5vw,44px);padding-top:110px;display:grid;& .side{gap:14px;max-height:calc(100vh - 120px);padding-right:4px;display:grid;position:sticky;top:100px;overflow:auto}& .back{color:var(--muted);align-items:center;gap:6px;font-weight:500;display:inline-flex}& .progress{gap:6px;display:grid}& .bar{background:var(--surface-2);border-radius:999px;height:6px;overflow:hidden}& .bar i{border-radius:inherit;width:0;height:100%;transition:width .4s var(--ease);background:#2f7d4a;display:block}& .outline-box summary{cursor:pointer;align-items:center;gap:8px;margin-bottom:10px;font-size:.9rem;font-weight:600;list-style:none;display:flex}& .outline-box summary::-webkit-details-marker{display:none}& .main{align-content:start;gap:16px;min-width:0;display:grid}& .title{letter-spacing:-.02em;font-size:clamp(1.7rem,3.4vw,2.4rem);line-height:1.2}& .lede{color:var(--ink-2);font-size:1.05rem}& .player,& .slides{aspect-ratio:16/9;border-radius:var(--radius-lg);box-shadow:var(--shadow-lg);background:#000;position:relative;overflow:hidden}& .player img{object-fit:cover;opacity:.9;width:100%;height:100%}& .player iframe,& .slides iframe{border:0;width:100%;height:100%}& .play{color:#111;cursor:pointer;width:76px;height:76px;transition:transform .25s var(--ease);background:#ffffffeb;border:0;border-radius:50%;place-items:center;padding-left:4px;display:grid;position:absolute;top:50%;left:50%;translate:-50% -50%;box-shadow:0 10px 40px #00000059}& .play:hover{transform:scale(1.08)}& .open-new{color:var(--muted);justify-self:start;align-items:center;gap:6px;display:inline-flex}& .missing{border-radius:var(--radius);background:var(--surface-2);color:var(--muted);text-align:center;padding:28px}& .done-row{border-top:1px solid var(--border);padding-top:8px}& .done-btn{border-radius:var(--radius-pill);border:1px solid var(--border-strong);cursor:pointer;background:0 0;align-items:center;gap:8px;padding:11px 20px;font-weight:500;display:inline-flex}& .done-btn[aria-pressed=true]{color:#fff;background:#2f7d4a;border-color:#2f7d4a}& .pager{grid-template-columns:1fr 1fr;gap:12px;display:grid}& .pg{border-radius:var(--radius);border:1px solid var(--border);background:var(--card);align-items:center;gap:12px;padding:14px 16px;font-size:.9rem;font-weight:500;transition:border-color .2s;display:flex}& .pg:hover{border-color:var(--ink)}& .pg span{gap:2px;display:grid}& .pg small{color:var(--muted);font-size:.72rem;font-weight:400}& .pg.next{text-align:right;grid-column:2;justify-content:flex-end}& .tabs:not([hidden]){border-radius:var(--radius-pill);background:var(--surface-2);scrollbar-width:none;justify-self:start;gap:4px;max-width:100%;padding:4px;display:flex;overflow-x:auto}& .tabs button{border-radius:var(--radius-pill);color:var(--muted);cursor:pointer;white-space:nowrap;background:0 0;border:0;align-items:center;gap:6px;padding:8px 16px;font-size:.88rem;font-weight:500;display:inline-flex}& .tabs button[aria-pressed=true]{background:var(--card);color:var(--ink);box-shadow:var(--shadow-sm)}& .tabs [data-badge]:not(:empty){color:#fff;text-align:center;background:#c2412d;border-radius:999px;min-width:18px;padding:0 5px;font-size:.7rem;line-height:18px}& .hub:not([hidden]){gap:14px;display:grid}& .hub-card{border-radius:var(--radius);border:1px solid var(--border);background:var(--card);gap:10px;padding:18px 20px;display:grid}& .hub-card.pinned{border-color:var(--ink)}& .hub-live{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:14px;display:flex}& .hub-live>div:first-child,& .work-head{gap:2px;display:grid}& .hub-actions{flex-wrap:wrap;gap:8px;display:flex}& .hub-list,& .hub-stack{gap:6px;padding:0;list-style:none;display:grid}& .hub-stack{gap:12px}& .hub-row{border-radius:var(--radius-sm);background:var(--card);align-items:center;gap:14px;padding:12px 14px;display:flex}& .hub-row.past{opacity:.6}& .hub-row.next{box-shadow:inset 0 0 0 1.5px var(--ink)}& .hub-row .no{width:26px;color:var(--muted);font-variant-numeric:tabular-nums}& .hub-row .grow{flex:1;min-width:0;display:grid}& .with-ico{align-items:center;gap:6px;display:inline-flex}& .chip{border-radius:var(--radius-pill);white-space:nowrap;align-items:center;gap:4px;padding:3px 10px;font-size:.75rem;font-weight:600;display:inline-flex}& .chip--ok{color:#1f5a30;background:#d9efdd}& .chip--warn{color:#7a4410;background:#f6e2c8}& .chip--bad{color:#8a2a1b;background:#f8e1dd}& .chip--muted{background:var(--surface-2);color:var(--muted)}& .chip--live{color:#fff;background:#c2412d}& .hub-form{border-top:1px solid var(--border);justify-items:start;gap:10px;padding-top:10px;display:grid}& .hub-form .field{width:100%}& .hub-form .or{margin:-4px 0}& .mine{flex-wrap:wrap;align-items:center;gap:6px;display:flex}& .u{text-decoration:underline}& .news-body{white-space:pre-line}}@media (width<=900px){.lesson-page{grid-template-columns:1fr;& .side{max-height:none;position:static;overflow:visible}}}@media (width<=767px){.lesson-page{padding-top:20px;& .pager{grid-template-columns:1fr}& .pg.next{grid-column:1}& .hub-live .cbtn{flex:auto}}}