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var(--color-primary), var(--color-accent))}.yt-grid{grid-template-columns:repeat(auto-fill,minmax(min(100%,260px),1fr));gap:clamp(.9rem,2vw,1.2rem);max-width:1200px;margin:2rem auto;padding:0 1rem;display:grid}.yt-thumb{cursor:pointer;aspect-ratio:16/9;appearance:none;contain:layout paint;background:#ffffff0d;border:0;border-radius:16px;width:100%;padding:0;line-height:0;transition:transform .2s,box-shadow .2s;display:block;position:relative;overflow:hidden;box-shadow:0 6px 25px #00000059}.yt-thumb:hover{transform:translateY(-3px);box-shadow:0 12px 40px #0000008c}.yt-thumb img{object-fit:cover;width:100%;height:100%;display:block;position:absolute;inset:0}.yt-overlay{-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);z-index:9999;overscroll-behavior:contain;touch-action:none;background:#000000bf;justify-content:center;align-items:center;width:100vw;height:100dvh;display:none;position:fixed;inset:0}.yt-overlay-content{aspect-ratio:16/9;flex:none;width:90%;max-width:900px;position:relative;transform:translateZ(0)}#ytPlayer{background:#000;border:none;border-radius:20px;width:100%;height:100%;display:block}.yt-close{color:#fff;cursor:pointer;z-index:1;background:0 0;border:none;font-size:2rem;position:absolute;top:-50px;right:0}html,body{overflow-x:hidden}.yt-search{width:100%;color:var(--color-text);background:#ffffff0d;border:1px solid #8cffdc59;border-radius:50px;outline:none;margin-bottom:2rem;padding:.9rem 1.1rem}.yt-search::placeholder{color:var(--color-muted)}.lesson-layout{gap:2rem;display:grid}@media 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0;border:none;padding:0;display:none}.lesson-card.show{display:block}.lesson-card h3{margin:0 0 1.2rem;font-size:1.6rem}.lesson-card h4{color:var(--color-secondary);margin:1.6rem 0 .6rem;font-weight:600}.lesson-card ul{max-width:100%;padding-left:1.2rem}.lesson-card li{color:var(--color-muted);margin-bottom:.45rem;line-height:1.6}.lesson-full-context{max-width:760px;margin:90px auto 0;padding:0 1.2rem}.lesson-full-context .lesson-section-title{text-align:center;letter-spacing:-.02em;color:var(--color-text);margin:0 0 20px;font-size:1.85rem}.lesson-context{text-align:left;color:var(--color-muted);font-size:1.05rem;line-height:1.9}.lesson-context>p:first-of-type{text-align:center;color:var(--color-muted);opacity:.95;margin:0 0 54px;font-size:1.05rem}.lesson-context h3{color:var(--color-secondary);letter-spacing:.02em;margin:62px 0 14px;font-size:1.15rem}.lesson-context h3:first-of-type{margin-top:0}.lesson-context p{color:var(--color-muted);margin:0 0 18px}.lesson-context 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0;border:none;padding:0}.lesson-seo-summary{cursor:pointer;-webkit-user-select:none;user-select:none;justify-content:space-between;align-items:baseline;gap:14px;padding:12px 0 16px;list-style:none;display:flex}.lesson-seo-summary::-webkit-details-marker{display:none}.lesson-seo-summary:after{content:"";opacity:.85;border-bottom:2px solid;border-right:2px solid;width:9px;height:9px;transition:transform .18s;transform:rotate(45deg)}.lesson-seo-toggle[open] .lesson-seo-summary:after{transform:rotate(-135deg)}#tab-lessons .lesson-video{display:none}#tab-lessons.lesson-selected .lesson-video{display:block!important}.lesson-moreHint{opacity:.85;cursor:pointer;font-style:italic}.lesson-shell{padding:0 1rem 90px}.lesson-cardWrap{background:#ffffff0a;border:1px solid #ffffff1a;border-radius:26px;max-width:1200px;margin:2rem auto 0;box-shadow:0 18px 60px #00000073}.lesson-cardInner{padding:26px}.lesson-back{color:var(--color-muted);margin:4px 0 18px;font-weight:600;text-decoration:none;display:inline-block}.lesson-back:hover{color:var(--color-secondary)}.lesson-title{letter-spacing:-.02em;word-break:break-word;margin:0 0 12px;font-size:clamp(1.65rem,3.6vw,2.6rem);line-height:1.18}.lesson-sub{color:var(--color-muted);margin:0 0 18px}.lesson-note{color:var(--color-muted);margin:0 0 18px;line-height:1.7}.lesson-grid{align-items:start;gap:26px;display:grid}@media (min-width:980px){.lesson-grid{grid-template-columns:minmax(0,520px) minmax(0,1fr)}}.lesson-video{aspect-ratio:16/9;background:#ffffff0d;border:1px solid #8cffdc2e;border-radius:18px;width:100%;overflow:hidden;box-shadow:0 10px 35px #00000073}.lesson-video 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1fr}}.lesson-moreList a{color:var(--color-secondary);opacity:.95;align-items:baseline;gap:10px;line-height:1.35;text-decoration:none;display:inline-flex}.lesson-moreList a:before{content:"";color:#8cffdce6;background:#8cffdce6;border-radius:999px;flex:none;width:6px;height:6px;margin-top:.55em}.lesson-moreList a:hover{opacity:1;color:var(--color-text)}.lesson-seo{opacity:0;transition:opacity .15s}body.watch-ready .lesson-seo{opacity:1}.yt-overlay{-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);overscroll-behavior:contain;touch-action:none;animation:.18s both ytOverlayFade;display:none;z-index:2147483000!important;background:#02040bdb!important;justify-content:center!important;align-items:center!important;width:100vw!important;height:100dvh!important;padding:72px clamp(16px,4vw,42px) 34px!important;position:fixed!important;inset:0!important}.yt-overlay.open{display:flex!important}.yt-overlay-content{background:#000;border-radius:18px;animation:.22s both ytPlayerRise;box-shadow:0 24px 70px #0000009e,0 0 0 1px #ffffff1f,0 0 28px #7f5af02e;aspect-ratio:16/9!important;flex:none!important;width:min(90vw,980px)!important;max-width:980px!important;max-height:calc(100dvh - 132px)!important;margin:0!important;padding:0!important;position:relative!important;overflow:visible!important;transform:none!important}.yt-overlay-content iframe,#ytPlayer{background:#000;border:0!important;border-radius:18px!important;width:100%!important;height:100%!important;display:block!important;position:absolute!important;inset:0!important}.yt-close{cursor:pointer;border-radius:50%;place-items:center;width:38px;height:38px;display:grid;z-index:2!important;color:#fff!important;background:#080c16eb!important;border:1px solid #ffffff38!important;font-size:26px!important;line-height:1!important;position:absolute!important;top:-50px!important;right:-2px!important}.yt-close:hover,.yt-close:focus{box-shadow:0 0 18px #ffd52424;border-color:#ffd5249e!important}@media (max-width:720px){.yt-overlay{padding:58px 14px 24px!important}.yt-overlay-content{width:90vw!important;max-height:calc(100dvh - 96px)!important}.yt-close{top:-44px!important}}@media (max-height:760px) and (min-width:900px){.yt-overlay-content{width:min(82vw,860px)!important}}@media (max-height:620px) and (min-width:760px){.yt-overlay-content{width:min(76vw,760px)!important}}@keyframes ytOverlayFade{0%{opacity:0}to{opacity:1}}@keyframes ytPlayerRise{0%{opacity:0;transform:translateY(10px)scale(.985)}to{opacity:1;transform:translateY(0)scale(1)}}.watch-v2,.lesson-shell{background:0 0!important}.lesson-cardWrap,.lesson-cardInner,.lesson-moreInner{background:#070a126b!important}