:root{--browser-gap:clamp(24px,3vw,48px)}body[data-library]{overflow-x:hidden}.learning-browser{width:min(1580px,94vw);margin:0 auto;padding:24px 0 48px;display:grid;grid-template-columns:minmax(0,1.08fr) minmax(420px,.92fr);gap:var(--browser-gap);height:calc(100svh - 74px);min-height:680px}.lesson-pane{min-width:0;position:relative;overflow:hidden;border:1px solid var(--line);background:#0c0e12;display:flex;flex-direction:column}.lesson-visual{position:relative;flex:1;min-height:360px;overflow:hidden;isolation:isolate}.lesson-visual:before{content:"";position:absolute;inset:0;background-image:var(--lesson-image);background-size:cover;background-position:center;filter:saturate(.8) contrast(1.07);transform:scale(1.02);z-index:-3}.lesson-visual:after{content:"";position:absolute;inset:0;background:linear-gradient(90deg,rgba(7,8,10,.96),rgba(7,8,10,.68) 52%,rgba(7,8,10,.2)),linear-gradient(0deg,#0c0e12 0%,transparent 45%);z-index:-2}.lesson-grid{position:absolute;inset:0;background-image:linear-gradient(rgba(255,255,255,.035) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.035) 1px,transparent 1px);background-size:42px 42px;mask-image:linear-gradient(to bottom,#000,transparent 78%);opacity:.65}.lesson-copy{position:relative;z-index:2;height:100%;padding:clamp(28px,4vw,58px);display:flex;flex-direction:column;justify-content:space-between;max-width:780px}.lesson-meta{display:flex;align-items:center;gap:12px;flex-wrap:wrap}.lesson-meta span{font-size:9px;font-weight:850;letter-spacing:.16em;text-transform:uppercase;color:var(--gold)}.lesson-live{padding:7px 9px;border:1px solid rgba(233,165,27,.35);background:rgba(233,165,27,.06)}.lesson-copy h1{font-size:clamp(48px,6.5vw,104px);line-height:.84;letter-spacing:-.045em;text-transform:uppercase;margin:18px 0 22px;max-width:760px}.lesson-copy p{max-width:650px;color:#c2c4c8;font-size:clamp(15px,1.35vw,19px);line-height:1.62}.lesson-start{display:inline-flex;align-items:center;gap:24px;width:max-content;max-width:100%;padding:16px 18px;background:var(--gold);color:#0b0c0e;font-size:10px;font-weight:900;letter-spacing:.12em;text-transform:uppercase;border:0;transition:.25s}.lesson-start:hover{gap:34px;transform:translateY(-2px)}.lesson-start.disabled{background:#1a1d22;color:#777b84;border:1px solid var(--line);pointer-events:none}.section-intro{padding:28px 32px;border-top:1px solid var(--line);display:grid;grid-template-columns:1fr auto;gap:20px;align-items:end}.section-intro h2{font-size:clamp(26px,2.5vw,40px);margin:7px 0 0;text-transform:uppercase}.section-intro p{margin:8px 0 0;color:var(--muted);line-height:1.5;max-width:650px}.section-counts{display:flex;gap:8px;flex-wrap:wrap;justify-content:flex-end}.section-counts span{border:1px solid var(--line);padding:8px 10px;color:var(--muted);font-size:9px;letter-spacing:.12em;text-transform:uppercase}.topic-pane{min-width:0;border-left:1px solid var(--line);display:flex;flex-direction:column;overflow:hidden;background:#090a0d}.topic-pane-head{padding:0 0 18px;flex:none}.topic-pane-title{display:flex;align-items:end;justify-content:space-between;gap:20px;margin-bottom:16px}.topic-pane-title h2{margin:0;font-size:clamp(26px,2.5vw,40px);letter-spacing:-.025em}.topic-pane-title span{color:var(--muted);font-size:9px;letter-spacing:.14em;text-transform:uppercase}.library-search{position:relative}.library-search input{width:100%;height:54px;padding:0 48px 0 17px;background:#0e1014;border:1px solid var(--line);color:#fff;outline:none;font-size:14px}.library-search input:focus{border-color:rgba(233,165,27,.55)}.library-search:after{content:"⌕";position:absolute;right:17px;top:50%;transform:translateY(-52%);color:var(--gold);font-size:22px}.topic-scroll{overflow-y:auto;overscroll-behavior:contain;padding-right:8px;scrollbar-width:thin;scrollbar-color:#3a3d44 transparent}.topic-group{border-top:1px solid var(--line)}.topic-group summary{list-style:none;cursor:pointer;display:grid;grid-template-columns:1fr auto;gap:15px;align-items:center;padding:18px 4px}.topic-group summary::-webkit-details-marker{display:none}.topic-group summary h3{margin:0;font-size:18px}.topic-group summary span{font-size:9px;color:var(--muted);letter-spacing:.12em;text-transform:uppercase}.topic-list{display:grid;gap:6px;padding:0 0 18px}.topic-item{width:100%;border:1px solid transparent;background:transparent;color:inherit;text-align:left;padding:13px 14px;cursor:pointer;transition:.2s;display:grid;grid-template-columns:1fr auto;gap:12px;align-items:center}.topic-item:hover,.topic-item.active{border-color:rgba(233,165,27,.34);background:rgba(233,165,27,.045)}.topic-item strong{font-size:14px;line-height:1.3}.topic-item small{display:block;margin-top:4px;color:var(--muted);font-size:11px}.topic-item em{font-style:normal;color:#62666f;font-size:8px;letter-spacing:.12em;text-transform:uppercase}.topic-item.live em{color:var(--gold)}.topic-empty{display:none;color:var(--muted);padding:26px 0}.hidden{display:none!important}
@media(min-width:1100px){.topic-pane{padding-left:clamp(24px,3vw,46px)}.lesson-pane{box-shadow:0 30px 100px rgba(0,0,0,.32)}}
@media(min-width:700px) and (max-width:1099px){.learning-browser{width:min(96vw,1100px);grid-template-columns:minmax(0,1fr) minmax(330px,.8fr);gap:22px;height:calc(100svh - 74px);min-height:650px}.lesson-copy{padding:34px}.lesson-copy h1{font-size:clamp(44px,6vw,68px)}.section-intro{padding:22px;grid-template-columns:1fr}.section-counts{justify-content:flex-start}.topic-pane{padding-left:20px}.topic-pane-title h2{font-size:26px}.topic-item{padding:11px 10px}}
@media(max-width:699px){body[data-library]{overflow-y:auto}.top{position:sticky}.top .wrap{width:100%;padding:0 14px}.nav{gap:12px;overflow-x:auto;white-space:nowrap;scrollbar-width:none}.nav::-webkit-scrollbar{display:none}.learning-browser{display:flex;flex-direction:column;width:100%;height:auto;min-height:0;padding:0;gap:0}.lesson-pane{border-left:0;border-right:0;min-height:calc(100svh - 74px)}.lesson-visual{min-height:66svh}.lesson-copy{padding:30px 22px 34px}.lesson-copy h1{font-size:clamp(44px,13vw,64px);margin-top:14px}.lesson-copy p{font-size:15px}.section-intro{padding:22px;grid-template-columns:1fr}.section-counts{justify-content:flex-start}.topic-pane{border-left:0;border-top:1px solid var(--line);padding:28px 22px 60px;overflow:visible}.topic-pane-head{position:sticky;top:74px;z-index:12;background:linear-gradient(#090a0d 78%,rgba(9,10,13,.92),transparent);padding:10px 0 22px}.topic-scroll{overflow:visible;padding:0}.topic-pane-title{margin-bottom:12px}.topic-pane-title h2{font-size:28px}.library-search input{height:52px}.topic-group summary{padding:17px 0}.topic-item{padding:14px 10px}.topic-list{gap:4px}}
@media(prefers-reduced-motion:reduce){.lesson-start,.topic-item{transition:none!important}}