:root{--bg:#ffffff;--surface:#f7f8fa;--surface-2:#eef0f4;--border:#dfe3ea;--text:#171a21;--text-dim:#5b6472;--accent:#2563eb;--accent-soft:#dbeafe;--ok:#15803d;--ok-soft:#dcfce7;--warn:#b45309;--err:#dc2626;--err-soft:#fee2e2;--radius:12px;--radius-sm:8px;--tap:44px;--mono:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,monospace;--header-h:52px;--safe-b:env(safe-area-inset-bottom,0px)}@media (prefers-color-scheme:dark){:root{--bg:#0f1115;--surface:#171a21;--surface-2:#1f232c;--border:#2a2f3a;--text:#e6e9ef;--text-dim:#9aa3b2;--accent:#5b9bff;--accent-soft:#16233d;--ok:#4ade80;--ok-soft:#122c1c;--warn:#fbbf24;--err:#f87171;--err-soft:#34161a}}*{box-sizing:border-box}html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--text);font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;font-size:16px;line-height:1.6;-webkit-font-smoothing:antialiased;overflow-wrap:break-word}a{color:var(--accent);text-decoration:none}a:active{opacity:.7}:focus-visible{outline:2px solid var(--accent);outline-offset:2px;border-radius:4px}.container{max-width:100%;padding:1rem 1rem 5rem}@media (min-width:700px){.container{max-width:780px;margin:0 auto;padding:2rem 1.5rem 4rem}}.site-header{position:-webkit-sticky;position:sticky;top:0;z-index:20;height:var(--header-h);background:color-mix(in srgb,var(--bg) 88%,transparent);-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border-bottom:1px solid var(--border)}.site-header .inner{height:100%;max-width:780px;margin:0 auto;padding:0 1rem;display:flex;align-items:center;gap:.6rem}.site-header .brand{font-weight:700;letter-spacing:-.02em;color:var(--text);font-size:1rem}.site-header .tag{display:none;color:var(--text-dim);font-size:.8rem}@media (min-width:700px){.site-header .tag{display:inline}}.top-nav{margin-left:auto;display:flex;gap:.25rem}.top-nav a{display:flex;align-items:center;min-height:36px;padding:0 .75rem;border-radius:var(--radius-sm);font-size:.9rem;font-weight:550}.top-nav a:hover{background:var(--surface-2)}.signout{margin:0;display:flex}.signout button{display:flex;align-items:center;min-height:36px;padding:0 .75rem;background:none;border:none;border-radius:var(--radius-sm);color:var(--text-dim);font:inherit;font-size:.9rem;font-weight:550;cursor:pointer}.signout button:hover{background:var(--surface-2);color:var(--text)}h1{font-size:1.4rem;line-height:1.25;letter-spacing:-.02em;margin:0 0 .5rem}h2{font-size:1.1rem;line-height:1.3;margin:2rem 0 .6rem}@media (min-width:700px){h1{font-size:1.85rem}h2{font-size:1.2rem}}p.lede{margin:0 0 1.5rem;font-size:.95rem}.muted,p.lede{color:var(--text-dim)}.muted{font-size:.875rem}.card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:1rem;margin-bottom:.6rem}.row-link{display:block;color:inherit}.row-link:active .card{background:var(--surface-2)}.card.row{display:flex;align-items:center;justify-content:space-between;gap:.75rem;min-height:var(--tap)}.row-title{font-weight:600;font-size:.975rem;line-height:1.35}.row-meta{font-size:.825rem;margin-top:.2rem}.chev,.row-meta{color:var(--text-dim)}.chev{flex:none;font-size:1.1rem}@media (hover:hover){.row-link:hover .card{border-color:var(--accent)}}.crumbs{align-items:center;gap:.25rem;font-size:.825rem;margin-bottom:.75rem}.crumbs span{opacity:.5}.pager{flex-direction:column;gap:.5rem;margin-top:2rem;padding-top:1rem;font-size:.9rem}.pager a{min-height:var(--tap);align-items:center;padding:0 .85rem;background:var(--surface);border-radius:var(--radius-sm)}@media (min-width:700px){.pager{flex-direction:row;justify-content:space-between}.pager a{flex:1 1}.pager a:last-child{justify-content:flex-end}}.outcome{border-left:3px solid var(--accent);border-radius:0 var(--radius-sm) var(--radius-sm) 0;padding:.75rem .9rem;margin-bottom:1.25rem}.hours{color:var(--text-dim);font-weight:400;font-size:.825rem}.module-summary{margin:-.25rem 0 .9rem;color:var(--text-dim);font-size:.9rem}.module-summary p{margin:0}.tabs{gap:.2rem;margin:0 -1rem 1.25rem;padding:0 1rem}.tab{display:flex;align-items:center;gap:.4rem;border-bottom:2px solid transparent;font-size:.925rem;padding:0 .75rem}.tab.active{border-bottom-color:var(--accent);font-weight:600}.badge{background:var(--surface-2);border:1px solid var(--border);border-radius:99px;font-size:.7rem;padding:.05rem .4rem}@media (min-width:700px){.tabs{margin:0 0 1.5rem;padding:0}}.md{line-height:1.7}.md>:first-child{margin-top:0}.md p{margin:0 0 1rem}.md h3{margin:1.75rem 0 .5rem}.md h4{font-size:.8rem;margin:1.4rem 0 .4rem;color:var(--text-dim);text-transform:uppercase;letter-spacing:.05em}.md ol,.md ul{padding-left:1.25rem;margin:0 0 1rem}.md li{margin-bottom:.35rem}.md table{margin:1rem 0;font-size:.875rem;-webkit-overflow-scrolling:touch}.md td,.md th{white-space:nowrap}.md th{font-weight:600}.md blockquote{border-left:3px solid var(--border);margin:1rem 0;padding:.1rem 0 .1rem .9rem}.md hr{border:none;border-top:1px solid var(--border);margin:1.75rem 0}code,kbd{font-family:var(--mono);font-size:.875em;border:1px solid var(--border);border-radius:5px;padding:.1em .35em}code,kbd,pre{background:var(--surface-2)}pre{border:1px solid var(--border);border-radius:var(--radius-sm);padding:.85rem;overflow-x:auto;font-size:.85rem;-webkit-overflow-scrolling:touch}pre code{background:none;border:none;padding:0}.katex-display{overflow-x:auto;overflow-y:hidden;padding:.25rem 0}.example{margin-bottom:.6rem;background:var(--surface)}.example summary{min-height:var(--tap);display:flex;align-items:center;padding:.6rem 1rem;cursor:pointer;font-weight:600;font-size:.925rem;list-style:none}.example summary::-webkit-details-marker{display:none}.example summary:before{content:"▸";margin-right:.5rem;color:var(--text-dim)}.example[open] summary:before{content:"▾"}.chat{display:flex;flex-direction:column;gap:.85rem}.chat-hint{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:.9rem 1rem;font-size:.925rem}.chat-hint p{margin:0 0 .5rem}.chat-hint p:last-child{margin:0}.chat-log{display:flex;flex-direction:column;gap:.75rem}.bubble{padding:.7rem .9rem;border-radius:var(--radius);max-width:88%;font-size:.95rem}.bubble.user{background:var(--accent);color:#fff;align-self:flex-end;border-bottom-right-radius:4px}.bubble.assistant{background:var(--surface);border:1px solid var(--border);align-self:flex-start;border-bottom-left-radius:4px}.bubble.assistant .md p:last-child{margin-bottom:0}.chat-error{background:var(--err-soft);border:1px solid var(--err);color:var(--err);border-radius:var(--radius-sm);padding:.6rem .85rem;font-size:.9rem}.chat-input{position:-webkit-sticky;position:sticky;bottom:0;display:flex;gap:.5rem;padding:.6rem 0 calc(.6rem + var(--safe-b));background:linear-gradient(to top,var(--bg) 72%,transparent)}.chat-input input{flex:1 1;min-height:var(--tap);background:var(--surface);border:1px solid var(--border);border-radius:22px;color:var(--text);font:inherit;font-size:16px;padding:0 1rem}.chat-input input:focus{outline:none;border-color:var(--accent)}.btn,.chat-input button{min-height:var(--tap);background:var(--accent);border:none;border-radius:22px;color:#fff;font:inherit;font-weight:600;font-size:.95rem;padding:0 1.25rem;cursor:pointer;white-space:nowrap}.btn{border-radius:var(--radius-sm);width:100%}@media (min-width:700px){.btn{width:auto}}.btn:disabled,.chat-input button:disabled{opacity:.45;cursor:not-allowed}.practice-head{display:flex;justify-content:space-between;align-items:baseline;gap:.75rem;font-size:.85rem;margin-bottom:.6rem}.options{display:flex;flex-direction:column;gap:.5rem;margin:1rem 0}.option{display:flex;align-items:flex-start;gap:.6rem;min-height:var(--tap);padding:.7rem .85rem;border:1px solid var(--border);border-radius:var(--radius-sm);cursor:pointer;font-size:.95rem;line-height:1.45}.option input{margin-top:.25rem;flex:none;width:1.05rem;height:1.05rem;accent-color:var(--accent)}.option.chosen{border-color:var(--accent);background:var(--accent-soft)}.option.right{border-color:var(--ok);background:var(--ok-soft)}.option.wrong{border-color:var(--err);background:var(--err-soft)}.option .key{font-weight:700;color:var(--text-dim);flex:none}.answer-input{width:100%;min-height:var(--tap);background:var(--bg);border:1px solid var(--border);border-radius:var(--radius-sm);color:var(--text);font:inherit;font-size:16px;padding:0 .85rem;margin:1rem 0}.verdict{font-weight:700;margin:1rem 0 .5rem;font-size:.975rem}.verdict.ok{color:var(--ok)}.verdict.no{color:var(--err)}.expected{font-weight:400;color:var(--text-dim);font-size:.875rem;margin-top:.25rem}.explanation{background:var(--surface-2);border-radius:var(--radius-sm);padding:.8rem .95rem;margin-bottom:1rem;font-size:.9rem}.explanation p:last-child{margin-bottom:0}.model-answer{border-left:3px solid var(--accent);padding-left:.85rem;margin:.75rem 0 1rem;font-size:.9rem}.finished{margin-top:1rem}.checklist{list-style:none;padding:0;margin:0}.checklist li{display:flex;align-items:flex-start;gap:.7rem;padding:.7rem 0;border-bottom:1px solid var(--border)}.checklist li:last-child{border-bottom:none}.dot{flex:none;width:.6rem;height:.6rem;border-radius:50%;margin-top:.5rem}.dot.ok{background:var(--ok)}.dot.warn{background:var(--warn)}.dot.err{background:var(--err)}.checklist .label{font-weight:600;font-size:.925rem}.checklist .hint{color:var(--text-dim);font-size:.85rem}.modes{display:grid;grid-gap:.6rem;gap:.6rem;grid-template-columns:1fr}@media (min-width:560px){.modes{grid-template-columns:1fr 1fr}}.mode{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:.9rem 1rem}.mode .n{color:var(--accent);font-weight:700;font-size:.75rem}.mode .t{font-weight:600;margin:.15rem 0 .2rem}.mode .d{color:var(--text-dim);font-size:.85rem;line-height:1.45}.admin-nav{position:-webkit-sticky;position:sticky;top:var(--header-h);z-index:15;background:var(--surface);border-bottom:1px solid var(--border);overflow-x:auto;scrollbar-width:none}.admin-nav::-webkit-scrollbar{display:none}.admin-nav-inner{max-width:900px;margin:0 auto;padding:0 1rem;gap:.25rem}.admin-nav a,.admin-nav-inner{display:flex;align-items:center}.admin-nav a{min-height:42px;padding:0 .75rem;font-size:.9rem;font-weight:550;color:var(--text-dim);white-space:nowrap}.admin-nav a:hover{color:var(--text)}.admin-who{margin-left:auto;padding-left:1rem;color:var(--text-dim);font-size:.8rem;white-space:nowrap}.admin .container{max-width:900px}.stat-grid{display:grid;grid-gap:.6rem;gap:.6rem;margin-bottom:1.5rem;grid-template-columns:repeat(auto-fit,minmax(120px,1fr))}.stat{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:.9rem 1rem}.stat-n{font-size:1.6rem;font-weight:700;line-height:1}.stat-l{color:var(--text-dim);font-size:.8rem;margin-top:.3rem}.stat-published .stat-n{color:var(--ok)}.stat-ai_generated .stat-n{color:var(--warn)}.notice{border-left:3px solid var(--warn)}.pill{display:inline-block;border-radius:99px;padding:.1rem .55rem;font-size:.75rem;font-weight:600;white-space:nowrap;background:var(--surface-2);color:var(--text-dim);border:1px solid var(--border)}.pill-published{background:var(--ok-soft);color:var(--ok);border-color:var(--ok)}.pill-ai_generated{background:var(--surface-2);color:var(--warn);border-color:var(--warn)}.pill-human_reviewed{background:var(--accent-soft);color:var(--accent);border-color:var(--accent)}.table-wrap{overflow-x:auto;-webkit-overflow-scrolling:touch;margin-bottom:1.5rem}.admin-table{width:100%;border-collapse:collapse;font-size:.875rem}.admin-table td,.admin-table th{border-bottom:1px solid var(--border);padding:.6rem .7rem;text-align:left;vertical-align:top}.admin-table th{background:var(--surface-2);font-weight:600;white-space:nowrap}.mono-cell{font-family:var(--mono);font-size:.8rem}.nowrap{white-space:nowrap}.filters{display:flex;gap:.4rem;flex-wrap:wrap;margin-bottom:1.25rem}.chip{display:inline-flex;align-items:center;min-height:36px;padding:0 .8rem;border:1px solid var(--border);border-radius:99px;font-size:.85rem;color:var(--text-dim)}.chip.active{background:var(--accent);border-color:var(--accent);color:#fff}.group-head{display:flex;flex-wrap:wrap;align-items:center;gap:.75rem;margin:2rem 0 .75rem}.group-head h2{margin:0;font-size:1rem}.group-actions,.topic-actions{display:flex;flex-wrap:wrap;align-items:center;gap:.5rem;margin-left:auto}.topic-actions{margin:0 0 1.5rem}.btn-sm{min-height:38px;padding:0 .9rem;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-sm);color:var(--text);font:inherit;font-size:.85rem;font-weight:550;cursor:pointer}.btn-sm.primary,.btn-sm:hover{border-color:var(--accent)}.btn-sm.primary{background:var(--accent);color:#fff}.btn-sm.danger{color:var(--err);border-color:var(--err)}.btn-sm:disabled{opacity:.5;cursor:not-allowed}.btn-link{font-weight:600;font-size:.9rem}.flash{font-size:.85rem}.flash.ok{color:var(--ok)}.flash.no{color:var(--err)}.review-head,.review-q{margin-bottom:1rem}.review-options{list-style:none;padding:0;margin:.5rem 0 0}.review-options li{padding:.4rem .6rem;border-radius:6px;font-size:.9rem;border:1px solid transparent}.review-options li.correct{background:var(--ok-soft);border-color:var(--ok);font-weight:550}.tick{color:var(--ok)}.answer-block{margin-top:.75rem}.perm-list{display:flex;flex-wrap:wrap;gap:.35rem}.perm{font-size:.75rem}.matrix{font-size:.8rem}.matrix .sticky-col{position:-webkit-sticky;position:sticky;left:0;z-index:2;background:var(--bg);min-width:220px}.matrix thead .sticky-col{background:var(--surface-2)}.matrix .rot{text-align:center;min-width:92px;font-size:.75rem}.matrix .cell{text-align:center;font-size:1rem}.matrix .cat-row td{background:var(--surface-2);font-weight:700;text-transform:uppercase;letter-spacing:.06em;font-size:.7rem;color:var(--text-dim)}.tiny{font-size:.72rem}.form-row{margin-bottom:.75rem}.form-row label{display:block;font-size:.85rem;font-weight:600;color:var(--text-dim)}.form-row input,.form-row select,.form-row textarea{display:block;width:100%;margin-top:.3rem;min-height:var(--tap);background:var(--bg);border:1px solid var(--border);border-radius:var(--radius-sm);color:var(--text);font:inherit;font-size:16px;padding:0 .75rem}.form-row textarea{padding:.6rem .75rem;min-height:90px}.form-row input:focus,.form-row select:focus{outline:none;border-color:var(--accent)}.diagram-grid{display:grid;grid-gap:.75rem;gap:.75rem;grid-template-columns:repeat(auto-fill,minmax(220px,1fr))}.diagram-card{margin-bottom:0}.diagram-thumb{background:var(--bg);border:1px solid var(--border);border-radius:var(--radius-sm);padding:.5rem;margin-bottom:.6rem;height:120px;display:flex;align-items:center;justify-content:center;overflow:hidden}.diagram-thumb svg{max-width:100%;max-height:100%;height:auto}.kind-tag{display:inline-block;background:var(--surface-2);border:1px solid var(--border);border-radius:4px;font-size:.68rem;text-transform:uppercase;letter-spacing:.04em;padding:.05rem .35rem;margin-right:.4rem;color:var(--text-dim)}.notes-bar{display:flex;flex-wrap:wrap;align-items:center;gap:.6rem;margin:2rem 0 .75rem}.notes-bar h2{font-size:1.1rem}.notes-bar .btn-sm{margin-left:auto}.notes-bar .btn-sm+.btn-sm{margin-left:0}.editor{border:1px solid var(--border);border-radius:var(--radius);background:var(--bg);overflow:hidden}.editor-modes{display:flex;flex-wrap:wrap;align-items:center;gap:.4rem;padding:.6rem .75rem;background:var(--surface);border-bottom:1px solid var(--border)}.editor-modes .chip{min-height:32px;font-size:.8rem}.editor-hint{flex:1 1 100%;font-size:.78rem}@media (min-width:700px){.editor-hint{flex:1 1;text-align:right}}.toolbar{display:flex;flex-wrap:wrap;gap:.15rem;padding:.4rem .6rem;background:var(--surface);border-bottom:1px solid var(--border)}.tb,.toolbar{align-items:center}.tb{min-width:34px;min-height:34px;display:inline-flex;justify-content:center;background:none;border:1px solid transparent;border-radius:6px;color:var(--text-dim);font:inherit;font-size:.85rem;font-weight:600;cursor:pointer}.tb:hover{background:var(--surface-2);color:var(--text)}.tb.on{background:var(--accent-soft);color:var(--accent);border-color:var(--accent)}.tb-sep{width:1px;height:20px;background:var(--border);margin:0 .3rem}.editor-body{padding:1rem;min-height:320px;max-height:65vh;overflow-y:auto}.editor-body:focus-within{outline:none}.editor-body .ProseMirror{outline:none;min-height:280px}.editor-body .ProseMirror p.is-editor-empty:first-child:before{content:attr(data-placeholder);color:var(--text-dim);float:left;height:0;pointer-events:none}.editor-body table{display:table;width:100%}.editor-body td,.editor-body th{white-space:normal;min-width:4rem}.editor-source{width:100%;min-height:420px;max-height:65vh;border:none;background:var(--bg);color:var(--text);font-family:var(--mono);font-size:.85rem;line-height:1.65;padding:1rem;resize:vertical}.editor-source:focus{outline:none}.video{margin:1.25rem 0}.video-frame{position:relative;width:100%;aspect-ratio:16/9;background:#000;border-radius:var(--radius);overflow:hidden;border:1px solid var(--border)}.video-frame iframe{position:absolute;inset:0;width:100%;height:100%;border:0}.video figcaption{margin-top:.5rem;font-size:.875rem;color:var(--text-dim)}.canvas-wrap{border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;background:var(--bg)}.canvas-bar{display:flex;align-items:center;gap:.75rem;padding:.5rem .75rem;background:var(--surface);border-bottom:1px solid var(--border);font-size:.85rem}.canvas-bar .btn-sm{margin-left:auto}.canvas{height:62vh;min-height:380px}@media (max-width:699px){.canvas{height:70vh}}.canvas-loading{height:100%;color:var(--text-dim);font-size:.9rem}.canvas-loading,.canvas-placeholder{display:flex;align-items:center;justify-content:center}.canvas-placeholder{flex-direction:column;gap:.75rem;text-align:center;min-height:220px;padding:2rem 1rem}.canvas-placeholder p{margin:0;color:var(--text-dim);font-size:.9rem;max-width:34ch}.diagram-view{border:1px solid var(--border);border-radius:var(--radius);background:var(--bg);padding:.75rem;margin:1.25rem 0;overflow-x:auto}.diagram-view svg{max-width:100%;height:auto;display:block;margin:0 auto}.diagram-view figcaption{margin-top:.6rem;font-size:.875rem;color:var(--text-dim)}:root{--sidebar-w:264px;--topbar-h:56px;--tabbar-h:58px}.only-desktop{display:none}@media (min-width:900px){.only-desktop{display:revert}.only-mobile{display:none!important}}.shell{min-height:100dvh;display:flex;flex-direction:column}.topbar{position:-webkit-sticky;position:sticky;top:0;z-index:40;display:flex;align-items:center;gap:.5rem;height:var(--topbar-h);padding:0 .75rem;background:var(--bg);border-bottom:1px solid var(--border)}.topbar-brand{font-weight:700;letter-spacing:-.02em;font-size:.95rem;padding:0 .25rem;white-space:nowrap}.topbar-right{margin-left:auto;display:flex;align-items:center;gap:.5rem}.who{font-size:.85rem;color:var(--text-dim);max-width:18ch;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.icon-btn{display:inline-flex;align-items:center;justify-content:center;width:var(--tap);height:var(--tap);flex:none;background:none;border:none;border-radius:var(--radius-sm);color:var(--text);cursor:pointer}.icon-btn:hover{background:var(--surface-2)}.icon-btn svg{width:22px;height:22px}.search-trigger{display:flex;align-items:center;gap:.5rem;margin-left:.25rem;min-height:38px;padding:0 .7rem;background:var(--surface);border:1px solid var(--border);border-radius:999px;color:var(--text-dim);font:inherit;font-size:.85rem;cursor:pointer}.search-trigger:hover{border-color:var(--accent);color:var(--text)}.search-trigger svg{width:16px;height:16px;flex:none}.search-trigger span{display:none}@media (min-width:900px){.search-trigger{min-width:260px}.search-trigger span{display:inline}}.search-trigger kbd{margin-left:auto;font-family:var(--mono);font-size:.68rem;border:1px solid var(--border);border-radius:4px;padding:.1rem .3rem;background:var(--bg)}.shell-body{display:flex;flex:1 1;min-height:0}.sidebar{width:var(--sidebar-w);flex:none;border-right:1px solid var(--border);background:var(--bg);padding:.75rem .5rem 2rem;position:-webkit-sticky;position:sticky;top:var(--topbar-h);height:calc(100dvh - var(--topbar-h));overflow-y:auto;overscroll-behavior:contain}.shell-main{flex:1 1;min-width:0;padding-bottom:calc(var(--tabbar-h) + var(--safe-b))}@media (min-width:900px){.shell-main{padding-bottom:0}}.shell-main .container{max-width:1180px;padding:1.25rem 1rem 3rem}@media (min-width:900px){.shell-main .container{padding:2rem 2rem 4rem}}.shell-main .example-body,.shell-main .lede,.shell-main .md{max-width:74ch}.nav{display:flex;flex-direction:column;gap:1px}.nav-head{margin:1rem 0 .35rem;font-size:.68rem;font-weight:700;text-transform:uppercase;letter-spacing:.09em}.nav-empty,.nav-head{padding:0 .7rem;color:var(--text-dim)}.nav-empty{margin:0;font-size:.82rem}.nav-item{display:flex;align-items:center;gap:.6rem;min-height:var(--tap);padding:0 .7rem;border-radius:var(--radius-sm);font-size:.9rem;font-weight:550;color:var(--text)}.nav-item:hover{background:var(--surface-2)}.nav-item.on{background:var(--accent-soft);color:var(--accent)}.nav-item .ico{display:flex;flex:none}.nav-item .ico svg{width:18px;height:18px}.nav-item.has-toggle{padding-right:0;gap:0}.nav-item-main{display:flex;align-items:center;gap:.6rem;flex:1 1;min-width:0;min-height:var(--tap);color:inherit}.nav-label{display:flex;flex-direction:column;min-width:0}.nav-code{font-family:var(--mono);font-size:.68rem;opacity:.75}.nav-name{font-size:.875rem;line-height:1.25;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.nav-toggle{display:flex;align-items:center;justify-content:center;width:var(--tap);height:var(--tap);flex:none;background:none;border:none;color:inherit;cursor:pointer;border-radius:var(--radius-sm)}.nav-toggle svg{width:16px;height:16px;transition:transform .15s}.nav-toggle.open svg{transform:rotate(90deg)}.nav-toggle:hover{background:var(--surface-2)}.nav-sub{list-style:none;margin:.15rem 0 .3rem;padding:0 0 0 1.5rem}.nav-sub a{display:flex;align-items:center;gap:.5rem;min-height:38px;padding:0 .6rem;border-radius:var(--radius-sm);font-size:.82rem;color:var(--text-dim)}.nav-sub a:hover{background:var(--surface-2);color:var(--text)}.mod-n{font-family:var(--mono);font-size:.7rem;flex:none}.mod-t{flex:1 1;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.mod-c{flex:none;font-size:.7rem;opacity:.7}.scrim{position:fixed;inset:0;z-index:50;background:rgb(0 0 0/.45)}.drawer{position:fixed;top:0;left:0;bottom:0;z-index:51;width:min(86vw,320px);background:var(--bg);border-right:1px solid var(--border);padding:.5rem .5rem calc(1.5rem + var(--safe-b));overflow-y:auto;overscroll-behavior:contain;animation:slide-in .18s ease-out}@keyframes slide-in{0%{transform:translateX(-100%)}}.drawer-head{display:flex;align-items:center;justify-content:space-between;padding:0 .25rem .5rem}.drawer-title{font-weight:700;font-size:.95rem}.drawer-foot{margin-top:1.5rem;padding:.9rem .7rem 0;border-top:1px solid var(--border)}.drawer-user{margin:0;font-size:.875rem;font-weight:600}.drawer-email{margin:.1rem 0 0;font-size:.78rem;color:var(--text-dim);word-break:break-all}.tabbar{position:fixed;left:0;right:0;bottom:0;z-index:45;display:flex;height:calc(var(--tabbar-h) + var(--safe-b));padding-bottom:var(--safe-b);background:var(--bg);border-top:1px solid var(--border)}.tabbar a,.tabbar button{flex:1 1;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:.15rem;background:none;border:none;cursor:pointer;font:inherit;font-size:.65rem;font-weight:600;color:var(--text-dim)}.tabbar svg{width:21px;height:21px}.tabbar .on{color:var(--accent)}.palette-wrap{position:fixed;inset:0;z-index:60}.palette{position:relative;z-index:61;width:min(92vw,620px);margin:12vh auto 0;background:var(--bg);border:1px solid var(--border);border-radius:var(--radius);box-shadow:0 24px 60px rgb(0 0 0/.28);overflow:hidden}.palette-input{display:block;width:100%;min-height:54px;padding:0 1rem;background:none;border:none;border-bottom:1px solid var(--border);color:var(--text);font:inherit;font-size:16px}.palette-input:focus{outline:none}.palette-results{max-height:min(52vh,420px);overflow-y:auto;padding:.35rem}.palette-hint{margin:0;padding:1.25rem .75rem;font-size:.875rem;color:var(--text-dim)}.palette-hit{display:flex;flex-direction:column;gap:.1rem;width:100%;text-align:left;padding:.6rem .75rem;border:none;border-radius:var(--radius-sm);background:none;color:inherit;font:inherit;cursor:pointer;min-height:var(--tap)}.palette-hit.on{background:var(--accent-soft)}.hit-title{font-size:.9rem;font-weight:550}.hit-meta{font-size:.75rem;color:var(--text-dim);font-family:var(--mono)}.palette-foot{padding:.5rem .85rem;border-top:1px solid var(--border);background:var(--surface);font-size:.72rem;color:var(--text-dim)}.palette-foot kbd{font-family:var(--mono);border:1px solid var(--border);border-radius:4px;padding:.05rem .3rem;background:var(--bg);margin-right:.15rem}.landing{padding-bottom:env(safe-area-inset-bottom,0)}.hero{padding:3rem 1.25rem 2.5rem;border-bottom:1px solid var(--border);background:radial-gradient(ellipse 120% 80% at 50% -10%,var(--accent-soft),transparent 70%)}.hero-inner,.section-inner{max-width:760px;margin:0 auto}.eyebrow{margin:0 0 .9rem;font-size:.7rem;font-weight:700;text-transform:uppercase;letter-spacing:.12em;color:var(--accent)}.hero-title{margin:0 0 1rem;font-size:2rem;line-height:1.12;letter-spacing:-.035em;font-weight:700}.hero-title .hl{color:var(--accent)}.hero-sub{margin:0 0 1.75rem;font-size:1.05rem;line-height:1.6;color:var(--text-dim);max-width:46ch}.hero-cta{display:flex;flex-wrap:wrap;align-items:center;gap:.75rem}.hero-cta .btn{width:auto}.btn-ghost{display:inline-flex;align-items:center;min-height:var(--tap);padding:0 .25rem;font-weight:600;font-size:.95rem;color:var(--text-dim)}.btn-ghost:hover{color:var(--accent)}.stat-strip{display:grid;grid-template-columns:1fr 1fr;grid-gap:1rem 1.5rem;gap:1rem 1.5rem;margin:2.5rem 0 0;padding:1.25rem 0 0;border-top:1px solid var(--border)}.stat-strip div{margin:0}.stat-strip dt{font-size:.72rem;font-weight:600;text-transform:uppercase;letter-spacing:.07em;color:var(--text-dim)}.stat-strip dd{margin:.15rem 0 0;font-size:1.5rem;font-weight:700;letter-spacing:-.02em;font-feature-settings:"tnum";font-variant-numeric:tabular-nums}.section{padding:2.75rem 1.25rem}.section.alt{background:var(--surface);border-top:1px solid var(--border);border-bottom:1px solid var(--border)}.section-title{margin:0 0 .4rem;font-size:1.3rem;letter-spacing:-.02em;line-height:1.25}.section-lede{margin:0 0 1.5rem;color:var(--text-dim);font-size:.925rem}.demo{border:1px solid var(--border);border-radius:var(--radius);background:var(--bg);padding:1rem}.bubble{margin-bottom:1rem}.bubble:last-of-type{margin-bottom:0}.bubble-who{display:block;margin-bottom:.3rem;font-size:.68rem;font-weight:700;text-transform:uppercase;letter-spacing:.09em;color:var(--text-dim)}.bubble.tutor .bubble-who{color:var(--accent)}.bubble-text{white-space:pre-wrap;font-size:.95rem;line-height:1.6;border-radius:var(--radius-sm);padding:.7rem .85rem;background:var(--surface-2)}.bubble.tutor .bubble-text{background:var(--accent-soft);border:1px solid transparent}.demo-foot{margin:1.1rem 0 0;padding-top:.9rem;border-top:1px solid var(--border);font-size:.85rem;line-height:1.55;color:var(--text-dim)}.two-col p{margin:0 0 1rem;line-height:1.65;font-size:.975rem}.two-col p:last-child{margin-bottom:0}.course-grid{display:grid;grid-gap:.6rem;gap:.6rem;grid-template-columns:1fr}.course-card{display:flex;flex-direction:column;gap:.15rem;background:var(--bg);border:1px solid var(--border);border-radius:var(--radius);padding:.9rem 1rem;min-height:var(--tap);color:inherit}.course-card:hover{border-color:var(--accent)}.course-code{font-family:var(--mono);font-size:.72rem;color:var(--accent);font-weight:600}.course-name{font-weight:600;line-height:1.3}.course-meta{font-size:.8rem;color:var(--text-dim)}.closing p{margin:0 0 1.5rem;line-height:1.65;font-size:.975rem;max-width:54ch}.landing-foot{padding:1.75rem 1.25rem calc(2.5rem + var(--safe-b));border-top:1px solid var(--border);background:var(--surface)}.landing-foot p{max-width:760px;margin:0 auto;font-size:.78rem;line-height:1.55;color:var(--text-dim)}@media (min-width:700px){.hero{padding:5rem 2rem 4rem}.hero-title{font-size:3rem}.hero-sub{font-size:1.15rem}.stat-strip{grid-template-columns:repeat(4,1fr)}.section{padding:4rem 2rem}.section-title{font-size:1.65rem}.demo{padding:1.5rem}.two-col{display:grid;grid-template-columns:1fr 1fr;grid-gap:1.5rem;gap:1.5rem}.two-col p{margin-bottom:0}.course-grid{grid-template-columns:repeat(auto-fill,minmax(230px,1fr))}.landing-foot{padding:2rem}}.cat-head{margin-bottom:2rem}.cat-head h1{margin:.35rem 0 .4rem}.term{margin-bottom:2.5rem}.term-head{display:flex;align-items:baseline;gap:.75rem;flex-wrap:wrap;padding-bottom:.6rem;margin-bottom:1.25rem;border-bottom:2px solid var(--border)}.term-head h2{margin:0;font-size:1.15rem;letter-spacing:-.02em}.term-meta{font-size:.8rem;color:var(--text-dim);margin-left:auto}.cat-group{margin-bottom:1.75rem}.cat-label{margin:0 0 .7rem;font-size:.7rem;font-weight:700;text-transform:uppercase;letter-spacing:.1em;color:var(--accent)}.cat-grid{display:grid;grid-gap:.75rem;gap:.75rem;grid-template-columns:1fr}@media (min-width:640px){.cat-grid{grid-template-columns:repeat(2,1fr)}}@media (min-width:1100px){.cat-grid{grid-template-columns:repeat(3,1fr)}}.cc{display:flex;flex-direction:column;gap:.4rem;padding:1rem;background:var(--bg);border:1px solid var(--border);border-radius:var(--radius);color:inherit;min-height:100%}.cc.live{border-left:3px solid var(--accent);transition:transform .14s ease,box-shadow .14s ease,border-color .14s ease}.cc.live:hover{transform:translateY(-2px);border-color:var(--accent);box-shadow:0 8px 24px rgb(0 0 0/.1)}.cc.live:active{transform:translateY(0)}.cc:not(.live){opacity:.62;background:var(--surface)}.cc-top{display:flex;align-items:center;gap:.5rem}.cc-code{font-family:var(--mono);font-size:.72rem;font-weight:600;color:var(--accent);letter-spacing:.02em}.cc-slot{margin-left:auto;font-size:.62rem;font-weight:600;text-transform:uppercase;letter-spacing:.06em;color:var(--text-dim);background:var(--surface-2);border-radius:999px;padding:.12rem .5rem}.cc-name{font-weight:600;font-size:.95rem;line-height:1.35}.cc-meta{display:flex;flex-wrap:wrap;gap:.35rem .7rem;font-size:.75rem;color:var(--text-dim)}.cc-meta .mono{font-family:var(--mono)}.cc-note{margin:.15rem 0 0;line-height:1.5;padding-left:.6rem;border-left:2px solid var(--border)}.cc-mods,.cc-note{font-size:.75rem;color:var(--text-dim)}.cc-mods{list-style:none;margin:.5rem 0 0;padding:0;display:flex;flex-direction:column;gap:.3rem;line-height:1.45}.cc-mods li{display:flex;gap:.45rem}.cc-mod-n{flex:none;font-family:var(--mono);font-size:.68rem;color:var(--accent);opacity:.8;padding-top:.05rem}.cc-foot{margin-top:auto;padding-top:.6rem}.cc-ready{font-size:.78rem;font-weight:600;color:var(--accent)}.cc-soon{font-size:.78rem;color:var(--text-dim)}.cat-foot{margin-top:2.5rem;max-width:62ch;line-height:1.6}@media (prefers-reduced-motion:reduce){.cc.live{transition:none}.cc.live:hover{transform:none}}.tabs{position:-webkit-sticky;position:sticky;top:var(--topbar-h);z-index:20;background:var(--bg);border-bottom:1px solid var(--border);margin-bottom:1.5rem;display:flex;gap:.25rem;overflow-x:auto;scrollbar-width:none;-webkit-overflow-scrolling:touch}.tabs::-webkit-scrollbar{display:none}.tab{position:relative;flex:none;min-height:var(--tap);padding:0 .9rem;background:none;border:none;color:var(--text-dim);font:inherit;font-size:.9rem;font-weight:600;cursor:pointer;white-space:nowrap}.tab:hover{color:var(--text)}.tab.active{color:var(--accent)}.tab.active:after{content:"";position:absolute;left:.6rem;right:.6rem;bottom:-1px;height:2px;background:var(--accent);border-radius:2px 2px 0 0}.tab .badge{display:inline-block;margin-left:.35rem;min-width:1.25rem;padding:0 .3rem;background:var(--surface-2);border-radius:999px;font-size:.7rem;font-weight:700;line-height:1.35;color:var(--text-dim)}.tab.active .badge{background:var(--accent-soft);color:var(--accent)}.md{font-size:1rem;line-height:1.72}.md>*+*{margin-top:1.1rem}.md h3{margin-top:2rem;font-size:1.05rem;letter-spacing:-.01em;padding-bottom:.3rem;border-bottom:1px solid var(--border)}.md h4{margin-top:1.5rem;font-size:.95rem}.md ol,.md ul{padding-left:1.4rem}.md li+li{margin-top:.4rem}.md strong{font-weight:650}.md code{font-family:var(--mono);font-size:.875em;border-radius:4px;padding:.1rem .32rem}.md code,.md pre{background:var(--surface-2)}.md pre{border:1px solid var(--border);border-radius:var(--radius-sm);padding:.9rem 1rem;overflow-x:auto;font-size:.85rem;line-height:1.6;-webkit-overflow-scrolling:touch}.md pre code{background:none;padding:0;font-size:inherit}.md blockquote{margin-left:0;padding-left:1rem;border-left:3px solid var(--accent);color:var(--text-dim)}.md table{width:100%;border-collapse:collapse;font-size:.9rem;display:block;overflow-x:auto}.md td,.md th{border:1px solid var(--border);padding:.5rem .7rem;text-align:left}.md th{background:var(--surface-2);font-weight:650}.example{border:1px solid var(--border);border-radius:var(--radius);margin-bottom:.75rem;overflow:hidden;background:var(--bg)}.example>summary{cursor:pointer;list-style:none;padding:.85rem 1rem;font-weight:600;font-size:.925rem;display:flex;align-items:center;gap:.5rem;min-height:var(--tap)}.example>summary::-webkit-details-marker{display:none}.example>summary:before{content:"›";display:inline-block;font-size:1.2rem;line-height:1;color:var(--accent);transition:transform .15s ease}.example[open]>summary:before{transform:rotate(90deg)}.example>summary:hover{background:var(--surface)}.example-body{padding:0 1rem 1rem;border-top:1px solid var(--border)}.example-body h4:first-child{margin-top:1rem}.topic-head{margin-bottom:1.25rem}.crumbs{display:flex;flex-wrap:wrap;gap:.3rem;font-size:.78rem;margin-bottom:.6rem}.crumbs,.crumbs a{color:var(--text-dim)}.crumbs a:hover{color:var(--accent)}.outcome{background:var(--accent-soft);border-radius:var(--radius-sm);padding:.8rem 1rem;font-size:.9rem;line-height:1.6;margin-bottom:1.5rem}.pager{display:flex;gap:.6rem;flex-wrap:wrap;margin-top:3rem;padding-top:1.5rem;border-top:1px solid var(--border)}.pager a{flex:1 1 240px;display:flex;flex-direction:column;gap:.15rem;padding:.8rem 1rem;border:1px solid var(--border);border-radius:var(--radius);color:inherit;transition:border-color .14s ease,transform .14s ease}.pager a:hover{border-color:var(--accent);transform:translateY(-1px)}.pager .dir{font-size:.7rem;text-transform:uppercase;letter-spacing:.08em;color:var(--text-dim);font-weight:700}.pager .ttl{font-size:.9rem;font-weight:600;line-height:1.35}@media (prefers-reduced-motion:reduce){.pager a:hover{transform:none}.example>summary:before{transition:none}}.auth-shell{min-height:calc(100dvh - var(--header-h));display:flex;align-items:center;justify-content:center;padding:1.25rem;padding-bottom:calc(1.25rem + var(--safe-b));background:var(--surface)}.auth-card{width:100%;max-width:400px;background:var(--bg);border:1px solid var(--border);border-radius:var(--radius);padding:1.75rem 1.5rem}.auth-card h1{margin:0 0 .5rem;font-size:1.4rem;letter-spacing:-.02em}.auth-card>.muted{margin:0 0 1.25rem}.auth-brand{margin:0 0 .35rem;font-size:.75rem;font-weight:700;text-transform:uppercase;letter-spacing:.1em;color:var(--accent)}.auth-form{margin:1.25rem 0 0}.auth-form label{display:block;font-size:.85rem;font-weight:600;color:var(--text-dim);margin-bottom:.3rem}.auth-form input{display:block;width:100%;min-height:var(--tap);background:var(--bg);border:1px solid var(--border);border-radius:var(--radius-sm);color:var(--text);font:inherit;font-size:16px;padding:0 .75rem;margin-bottom:.85rem}.auth-form input:focus{outline:none;border-color:var(--accent)}.btn-block{width:100%}@media (min-width:700px){.btn-block{width:100%}}.btn-primary{background:var(--accent);color:#fff}.auth-notice{background:var(--accent-soft);color:var(--text);padding:.7rem .85rem;font-size:.875rem;margin:0 0 .25rem}.auth-notice,.auth-result{border-radius:var(--radius-sm)}.auth-result{margin-top:1rem;padding:.75rem .85rem;font-size:.9rem}.auth-result p{margin:0}.auth-result.ok{background:var(--ok-soft);color:var(--ok)}.auth-result.err{background:var(--err-soft);color:var(--err)}.auth-foot{margin:1.25rem 0 0;font-size:.8rem;line-height:1.5;color:var(--text-dim)}.dev-link{display:block;margin-top:.5rem;font-family:var(--mono);font-size:.7rem;word-break:break-all;color:inherit}.notice{border-radius:var(--radius-sm);padding:.8rem .95rem;font-size:.875rem;line-height:1.55;margin-bottom:1.25rem}.notice-warn{background:var(--surface-2);border:1px solid var(--warn)}.btn-row{gap:.5rem}.btn-row,.row-actions{display:flex;flex-wrap:wrap;align-items:center}.row-actions{gap:.4rem}.row-msg{font-size:.78rem;color:var(--text-dim)}@media (prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important;scroll-behavior:auto!important}}@media print{.btn,.chat-input,.pager,.site-header,.tabs{display:none}.container{max-width:100%;padding:0}.card,.example{border:none;background:none}}.small{font-size:.8rem}.mono{font-family:var(--mono)}.imp-list{display:flex;flex-direction:column;gap:.5rem;margin-top:1rem}.imp-row{display:grid;grid-template-columns:auto 7.5rem 1fr auto;align-items:center;grid-gap:.75rem;gap:.75rem;padding:.7rem .9rem;border:1px solid var(--border);border-radius:var(--radius-sm);background:var(--surface);cursor:pointer}.imp-row:hover{border-color:var(--accent)}.imp-row.is-new{border-left:3px solid var(--warn)}.imp-code{font-family:var(--mono);font-weight:600;font-size:.85rem}.imp-name{font-size:.9rem}.imp-nums{display:flex;flex-direction:column;align-items:flex-end;gap:.15rem;font-size:.78rem;color:var(--text-dim);text-align:right}.imp-behind{color:var(--warn)}.imp-same{color:var(--ok)}.imp-err{margin:.5rem 0 0;padding:.7rem;background:var(--surface-2);border-radius:var(--radius-sm);font-family:var(--mono);font-size:.78rem;white-space:pre-wrap;overflow-x:auto}.imp-report{margin-top:.9rem}.imp-report-head{font-family:var(--mono);font-size:.85rem;margin:0 0 .3rem}.imp-report ul{margin:0;padding-left:1.1rem;font-size:.82rem;color:var(--text-dim)}.imp-republished{font-size:.82rem;color:var(--warn);margin:.4rem 0 0}@media (max-width:640px){.imp-row{grid-template-columns:auto 1fr;row-gap:.35rem}.imp-name,.imp-nums{grid-column:2}.imp-nums{align-items:flex-start;text-align:left}}