:root{--color-bg:#f4f6fb;--color-text:#171c29;--color-surface:#fff;--color-surface-muted:#edf1f8;--color-muted:#535c72;--color-subtle:#2f3850;--color-border:#171c2924;--color-border-strong:#171c2938;--color-navbar-bg:#f4f6fbdb;--color-notice-bg:#1877ff24;--color-notice-text:#0f63d8;--color-link:#0f63d8;--hero-bg:#e9f0ff;--hero-text:#182b4d;--hero-muted:#354b73;--color-black:var(--color-bg);--color-white:var(--color-text);--color-dark-gray:var(--color-surface);--border-radius-sm:8px;--border-radius-md:16px;--border-radius-lg:24px;--border-radius-full:9999px;--shadow-glow:0 0 20px #0f63d833;--shadow-elevation:0 14px 30px #0f152629;--shadow-card:0 10px 26px #0f152614, inset 0 1px 0 #ffffffb3}@media 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20px #0f63d833;--shadow-elevation:0 14px 30px #0f152629;--shadow-card:0 10px 26px #0f152614, inset 0 1px 0 #ffffffb3}:root[data-theme=dark]{--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark;--color-bg:#080b12;--color-text:#f2f5ff;--color-surface:#111624;--color-surface-muted:#0c1120;--color-muted:#b2bacf;--color-subtle:#d5dcef;--color-border:#f2f5ff1f;--color-border-strong:#f2f5ff33;--color-navbar-bg:#080b12d1;--color-notice-bg:#1877ff26;--color-notice-text:#70b2ff;--color-link:#9bc6ff;--hero-bg:#070b14;--hero-text:#f2f5ff;--hero-muted:#c6cee2;--shadow-glow:0 0 20px #70b2ff3d;--shadow-elevation:0 12px 32px #00000085;--shadow-card:0 10px 26px #0000006b, inset 0 1px 0 #ffffff14}*{box-sizing:border-box;margin:0;padding:0}body{background-color:var(--color-bg);color:var(--color-text);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif,Apple Color Emoji,Segoe UI 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span{color:#f2f5ff;background:#080b12d1;border-radius:5px;padding:1px 5px;font-size:.72rem;font-weight:800;position:absolute;bottom:4px;right:4px}.lecture-copy{min-width:0}.lecture-copy strong{color:var(--color-text);-webkit-line-clamp:2;-webkit-box-orient:vertical;font-size:.94rem;line-height:1.16;display:-webkit-box;overflow:hidden}.lecture-copy em{color:var(--color-muted);margin-top:5px;font-size:.8rem;font-style:normal;font-weight:700;display:block}.finished-avatars{gap:-4px;margin-top:6px;display:flex}.avatar-circle{background:var(--color-link);width:20px;height:20px;color:var(--color-bg);border:2px solid 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var(--color-border);border-radius:var(--border-radius-sm);width:42px;height:42px;color:var(--color-text);place-items:center;display:inline-grid}.watch-icon-link:hover,.watch-icon-link:focus-visible{border-color:var(--color-link);opacity:1}.watch-icon-link.is-finished{color:#10b981;background:#10b9811a;border-color:#10b981}.finished-check{color:#10b981;vertical-align:middle;margin-left:6px;display:inline-block}.watch-context-grid,.watch-notes-grid{gap:18px;display:grid}.watch-context-grid{grid-area:2/1;grid-template-columns:1fr}.watch-notes-grid{display:contents}.watch-my-note-panel{grid-area:3/1}.watch-team-note-panel{grid-area:1/2/span 3}.watch-context-panel{padding:11px 15px}.watch-context-panel h3,.watch-notes-panel h3{letter-spacing:0;margin:3px 0 8px;font-size:1.08rem}.watch-context-panel p{color:var(--color-muted);line-height:1.35}.watch-pill-row{flex-wrap:wrap;gap:8px;margin-top:8px;display:flex}.watch-pill-row span{border:1px solid var(--color-border);border-radius:var(--border-radius-full);color:var(--color-muted);padding:6px 10px;font-size:.84rem;font-weight:800}.understanding-list{gap:9px;display:grid}.understanding-list label{color:var(--color-subtle);grid-template-columns:18px minmax(0,1fr);gap:10px;line-height:1.25;display:grid}.understanding-list input{width:16px;height:16px;accent-color:var(--color-link)}.watch-notes-panel{border-radius:var(--border-radius-lg);flex-direction:column;min-height:0;padding:16px;display:flex}.watch-notes-panel textarea{resize:vertical;border:1px solid var(--color-border);border-radius:var(--border-radius-sm);background:var(--color-surface-muted);width:100%;min-height:90px;color:var(--color-text);font:inherit;margin:2px 0 12px;padding:12px}.watch-notes-panel>textarea{flex:auto}.watch-notes-panel>button{border-radius:var(--border-radius-full);background:var(--color-link);min-height:38px;color:var(--color-bg);padding:8px 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a{opacity:1;gap:7px;min-height:138px;padding:15px;display:grid}.resource-strip span{color:var(--color-link);letter-spacing:.1em;text-transform:uppercase;font-size:.7rem;font-weight:900}.resource-strip strong{line-height:1.15}.resource-strip em{color:var(--color-muted);font-size:.88rem;font-style:normal;line-height:1.32}@media (width<=1180px){.watch-lab{grid-template-columns:1fr;min-height:0}.watch-sidebar{height:auto;max-height:none;position:relative;top:0}.lecture-list{max-height:54vh}.watch-main{grid-template-rows:auto;grid-template-columns:1fr;height:auto}.watch-player-panel,.watch-context-grid,.watch-my-note-panel,.watch-team-note-panel{grid-area:auto}.watch-player{width:min(100%,640px);height:auto}.watch-notes-grid{grid-template-rows:auto;min-height:0;display:grid}.resource-strip{grid-template-columns:repeat(2,minmax(0,1fr))}}@media (width<=720px){.watch-container{padding:14px!important}.course-rail,.watch-context-grid,.watch-notes-grid,.watch-heading-row,.resource-strip,.note-reply-box{grid-template-columns:1fr}.course-rail{grid-template-columns:repeat(2,minmax(0,1fr))}.watch-actions{justify-content:flex-start}}