:root{--bg:#f6f8fb;--card:#fff;--text:#111827;--muted:#6b7280;--border:#e5e7eb;--brand:#1d4ed8;--brand-2:#2563eb;--danger:#b91c1c;--shadow:0 10px 30px rgba(0,0,0,.06);--radius:16px}*{box-sizing:border-box}body,html{height:100%}body{margin:0;font-family:ui-sans-serif,system-ui,-apple-system,Segoe UI,Roboto,Helvetica,Arial,Apple Color Emoji,Segoe UI Emoji;color:var(--text);background:linear-gradient(180deg,#eef4ff,var(--bg))}.container{max-width:1200px;margin:0 auto;padding:18px}.hr{height:1px;background:var(--border);margin:16px 0}.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));grid-gap:14px;gap:14px}.h1{font-size:28px;margin:0 0 8px;letter-spacing:-.02em}.h2{font-size:18px;margin:0;font-weight:650}.h3{font-size:14px;margin:16px 0 6px;text-transform:uppercase;letter-spacing:.06em}.h3,.muted{color:var(--muted)}.card{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);padding:16px}a.card{display:block;text-decoration:none;color:inherit;transition:transform .12s ease,box-shadow .12s ease}a.card:hover{transform:translateY(-1px);box-shadow:0 14px 40px rgba(0,0,0,.09)}.badge{display:inline-block;font-size:12px;padding:4px 10px;border-radius:999px;background:#eff6ff;border:1px solid #dbeafe;color:#1e40af;margin-right:8px}.topbar{background:hsla(0,0%,100%,.85);-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);border-bottom:1px solid var(--border)}.topbarInner{max-width:1200px;margin:0 auto;padding:14px 18px}.brandTitle{font-weight:800;font-size:18px;margin:0}.brandSub{margin:4px 0 0;color:var(--muted);font-size:13px}.navlinks a{margin-right:12px;color:var(--brand);font-weight:650}.navlinks a:hover{text-decoration:underline}.split{display:grid;grid-template-columns:1fr 1fr;grid-gap:14px;gap:14px;align-items:start}.pane{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);overflow:hidden}.paneHeader{padding:12px 14px;border-bottom:1px solid var(--border);background:linear-gradient(180deg,#fff,#f9fbff);font-weight:750}.paneBody{padding:14px}@media (max-width:900px){.split{grid-template-columns:1fr}}.banner{border:1px solid #fecaca;background:#fff1f2;color:#7f1d1d;border-radius:12px;padding:10px 12px;margin-bottom:12px}.banner strong{font-weight:800}.block{margin:12px 0}.label{font-weight:700;margin-bottom:6px}.textarea{width:100%;border:1px solid var(--border);border-radius:12px;padding:10px 12px;font-size:14px;line-height:1.4;outline:none}.textarea:focus{border-color:#bfdbfe;box-shadow:0 0 0 4px rgba(37,99,235,.12)}.card ul{margin:8px 0 0 18px}.card li{margin:6px 0}.brandRow{align-items:flex-end;justify-content:space-between;gap:14px}.brandRow,.navlinks{display:flex;flex-wrap:wrap}.navlinks{gap:12px}.navlinks a{padding:8px 10px;border-radius:999px;border:1px solid #dbeafe;background:#eff6ff;color:#1e40af;font-weight:700;text-decoration:none}.navlinks a:hover{background:#dbeafe}.btn{-webkit-appearance:none;-moz-appearance:none;appearance:none;border:1px solid #1d4ed8;background:#1d4ed8;color:#fff;font-weight:750;padding:10px 14px;border-radius:12px;cursor:pointer}.btn:disabled{opacity:.6;cursor:not-allowed}.error{color:#b91c1c;font-weight:650}.aiBox{border:1px solid var(--border);border-radius:12px;padding:12px;background:#fff}.aiLabel{font-size:12px;color:var(--muted);text-transform:uppercase;letter-spacing:.06em;margin-bottom:8px;font-weight:750}.aiText{white-space:pre-wrap;line-height:1.5}.workbookRow{display:flex;align-items:flex-start;justify-content:space-between;gap:10px;margin-bottom:6px}.workbookTools{display:flex;gap:8px;flex-wrap:wrap;align-items:center}.btnGhost{border:1px solid var(--border);padding:8px 10px;border-radius:12px;font-weight:750}.btnGhost:hover{background:#f9fbff}.btnDanger{border:1px solid #fecaca;background:#fff1f2;color:#7f1d1d;padding:8px 10px;border-radius:12px;font-weight:800;cursor:pointer}.toolbarRow{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap}.toolbarButtons{display:flex;gap:8px;flex-wrap:wrap}.btnGhost{border:1px solid #d1d5db;background:#fff;color:#111827;padding:8px 12px;border-radius:10px;font-weight:600;cursor:pointer}.btnGhost:hover{background:#f9fafb}.resourceGrid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));grid-gap:10px;gap:10px;margin:10px 0 18px}.resourceCard{display:block;border:1px solid #e5e7eb;border-radius:12px;padding:12px;background:#fff;text-decoration:none;color:inherit}.resourceCard:hover{border-color:#94a3b8;box-shadow:0 6px 18px rgba(15,23,42,.08)}.resourceCard p{margin:6px 0 0;line-height:1.35}.videoAssistant{border-left:5px solid #6366f1}