:root{--ink:#142033;--plaque:#1b3a6b;--plaque-deep:#12284c;--enamel:#f4f0e4;--chalk:#e6e2d0;--board:#2c4638;--board-edge:#1d3027;--wall:#c5d0da;--wood:#6b4a32;--wood-dark:#4a3222;--pen-red:#d0122a;--paper:#f4f7f9;--muted:#5c6b7a;--line:#1420331f;--shadow:0 18px 40px #14203329;--font-display:"Unbounded", sans-serif;--font-body:"Onest", sans-serif;--font-mono:"IBM Plex Mono", ui-monospace, monospace;--radius:14px;--header-h:72px}*,:after,:before{box-sizing:border-box}html{scroll-behavior:smooth}body{min-height:100vh;color:var(--ink);background:linear-gradient(180deg,#ffffff59,transparent 180px),var(--wall);font-family:var(--font-body);margin:0;font-size:17px;line-height:1.5}iframe,img{max-width:100%}a{color:inherit;text-decoration:none}button,input{font:inherit}:focus-visible{outline:3px solid var(--pen-red);outline-offset:3px}.skip-link{z-index:80;background:var(--enamel);color:var(--ink);padding:8px 12px;position:absolute;top:-40px;left:12px}.skip-link:focus{top:12px}.wrap{width:min(1120px,100% - 32px);margin-inline:auto}.site-header{z-index:40;height:var(--header-h);border-bottom:1px solid var(--line);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);background:#c5d0daeb;position:sticky;top:0}.site-header__inner{height:var(--header-h);gap:20px}.brand,.site-header__inner{align-items:center;display:flex}.brand{flex-shrink:0;gap:10px}.brand__mark{background:var(--plaque);width:36px;height:36px;color:var(--enamel);border:2px solid var(--enamel);box-shadow:0 0 0 2px var(--plaque);place-items:center;font-size:11px;font-weight:800;display:grid}.brand__mark,.brand__name{font-family:var(--font-display)}.brand__name{letter-spacing:.02em;font-size:15px;font-weight:700}.brand__tag{color:var(--muted);letter-spacing:0;font-size:12px;font-weight:500;font-family:var(--font-body);margin-top:1px;display:block}.grade-strip{scrollbar-width:none;gap:6px;margin-left:auto;padding:6px 0;display:flex;overflow-x:auto}.grade-strip::-webkit-scrollbar{display:none}.grade-pill{min-width:40px;height:40px;color:var(--ink);font-family:var(--font-display);background:0 0;border:1.5px solid #0000;flex:none;place-items:center;font-size:16px;font-weight:700;display:grid}.grade-pill.is-active{background:var(--plaque);color:var(--enamel);border-color:var(--enamel);box-shadow:0 0 0 2px var(--plaque)}.grade-pill:hover:not(.is-active){border-color:var(--plaque)}.site-footer{background:var(--ink);color:var(--chalk);margin-top:72px;padding:36px 0 28px}.site-footer a:hover{color:#fff}.footer-grid{grid-template-columns:1.3fr repeat(3,minmax(0,1fr));gap:28px;display:grid}.footer-title{font-family:var(--font-display);letter-spacing:.08em;text-transform:uppercase;color:#e6e2d0b3;margin:0 0 12px;font-size:13px}.footer-links{gap:8px 14px;margin:0;padding:0;list-style:none}.crumbs,.footer-links{flex-wrap:wrap;display:flex}.crumbs{color:var(--muted);align-items:center;gap:8px;margin:22px 0 8px;font-size:14px}.crumbs a:hover{color:var(--plaque)}.crumbs__sep{opacity:.5}.page-hero{grid-template-columns:auto 1fr;align-items:end;gap:24px;margin:18px 0 32px;display:grid}.page-kicker{color:var(--muted);font-family:var(--font-mono);letter-spacing:.04em;margin:0 0 8px;font-size:13px}.page-title{font-family:var(--font-display);letter-spacing:-.03em;margin:0;font-size:clamp(32px,5vw,56px);line-height:1.05}.page-lead{max-width:46ch;color:var(--muted);margin:12px 0 0}.plaque{background:linear-gradient(180deg,#244a82,var(--plaque) 42%,var(--plaque-deep));width:112px;height:128px;color:var(--enamel);border:3px solid var(--enamel);box-shadow:0 0 0 3px var(--plaque),0 10px 0 var(--plaque-deep),var(--shadow);text-align:center;place-items:center;display:grid}.plaque__label{font-family:var(--font-mono);letter-spacing:.18em;text-transform:uppercase;opacity:.8;font-size:10px}.plaque__num{font-family:var(--font-display);font-size:52px;font-weight:800;line-height:.9}.plaque__num.is-wide{font-size:40px}.corridor{gap:48px;display:grid}.wing{gap:16px;display:grid}.wing__head{border-bottom:1px solid var(--line);justify-content:space-between;align-items:baseline;gap:12px;padding-bottom:8px;display:flex}.wing__title{font-family:var(--font-display);margin:0;font-size:18px}.wing__caption{color:var(--muted);font-size:14px}.door-grid{grid-template-columns:repeat(4,1fr);gap:16px;display:grid}.door{background:linear-gradient(180deg,#7a563b,var(--wood));box-shadow:var(--shadow);color:var(--enamel);min-height:220px;padding:18px 16px 16px;display:block}.door:focus-visible .plaque,.door:hover .plaque{transform:translateY(-3px)}.door__frame{justify-items:center;gap:16px;display:grid}.door__meta{border-top:1px solid #f4f0e440;justify-content:space-between;align-items:end;gap:8px;width:100%;padding-top:8px;font-size:13px;display:flex}.door__count{font-family:var(--font-mono);opacity:.8}.subject-nav{top:var(--header-h);z-index:20;background:color-mix(in srgb,var(--wall) 88%,#fff);scrollbar-width:none;gap:8px;margin:0 0 28px;padding:10px 0;display:flex;position:sticky;overflow-x:auto}.subject-nav::-webkit-scrollbar{display:none}.subject-chip{background:var(--paper);border:1px solid var(--line);flex:none;align-items:center;gap:8px;padding:8px 12px;font-size:14px;font-weight:500;display:inline-flex}.enamel-pin{background:radial-gradient(circle at 32% 28%,#ffffffc7,transparent 38%),var(--pin,var(--plaque));border-radius:50%;flex:none;width:18px;height:18px;box-shadow:inset 0 -2px 3px #14203347,0 1px #ffffff8c}.subject-list{gap:16px;padding-bottom:8px;display:grid}.subject-row{background:var(--enamel);box-shadow:0 0 0 3px color-mix(in srgb,var(--pin,var(--plaque)) 22%,transparent),0 8px 0 color-mix(in srgb,var(--pin,var(--plaque)) 28%,var(--plaque-deep));grid-template-columns:22px minmax(0,1fr) auto;align-items:center;gap:16px;padding:18px 20px;display:grid}.subject-row .enamel-pin{width:22px;height:22px}.lesson-card,.subject-row{transition:transform .16s}.subject-row strong{font-family:var(--font-display);letter-spacing:-.03em;font-size:clamp(18px,2.4vw,24px);font-weight:700}.subject-row__count{color:var(--muted);font-family:var(--font-mono);font-size:13px}.lesson-list{grid-template-columns:1fr 1fr;gap:12px;padding-bottom:8px;display:grid}.lesson-card{background:var(--enamel);box-shadow:0 6px 0 color-mix(in srgb,var(--pin,var(--plaque)) 18%,var(--wall));grid-template-columns:16px 4.2em minmax(0,1fr);align-items:baseline;gap:10px 12px;padding:14px 16px;display:grid}.lesson-card 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var(--line);padding:16px}.side-card h2{font-size:14px;font-family:var(--font-display);margin:0 0 4px}.side-card__meta{color:var(--muted);font-family:var(--font-mono);margin:0 0 12px;font-size:13px}.side-list{gap:6px;max-height:min(70vh,640px);margin:0;padding:0;list-style:none;display:grid;overflow:auto}.side-list a{align-items:baseline;gap:10px;padding:8px;font-size:14px;display:flex}.side-list .lesson-num{flex:none;min-width:2.6em;font-size:15px}.side-list a.is-active,.side-list a:hover{background:color-mix(in srgb,var(--plaque) 8%,#fff)}.search{border:1px solid var(--line);background:var(--paper);width:100%;margin:0 0 24px;padding:12px 14px}.grade-switch{gap:8px;margin-top:8px;display:flex}.ghost-link{color:var(--plaque);font-weight:600}.home-hero{padding:36px 0 28px}.home-hero h1{max-width:14ch;font-family:var(--font-display);letter-spacing:-.04em;margin:0;font-size:clamp(40px,8vw,76px);line-height:.95}.home-hero p{max-width:46ch;color:var(--ink);margin:16px 0 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