:root{--bg:#0f1419;--surface:#1a212b;--surface-2:#222b38;--border:#2c3744;--text:#e6edf3;--text-dim:#9aa7b4;--accent:#4f9cf9;--accent-soft:#1e3a5f;--good:#3fb950;--good-soft:#16341f;--bad:#f85149;--bad-soft:#3d1d1c;--warn:#d29922;--radius:14px;--shadow:0 6px 24px #00000059;--maxw:720px}*{box-sizing:border-box;margin:0;padding:0}html,body{background:var(--bg);height:100%;color:var(--text);-webkit-font-smoothing:antialiased;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif;line-height:1.55}#app{min-height:100%;max-width:var(--maxw);flex-direction:column;margin:0 auto;padding:0 16px;display:flex}#topbar{background:linear-gradient(var(--bg) 80%, transparent);z-index:10;justify-content:space-between;align-items:center;padding:18px 4px 14px;display:flex;position:sticky;top:0}.brand{cursor:pointer;-webkit-user-select:none;user-select:none;align-items:center;gap:10px;display:flex}.brand-mark{background:var(--accent);color:#06121f;letter-spacing:.5px;border-radius:8px;padding:4px 8px;font-size:13px;font-weight:800}.brand-mark.lg{border-radius:10px;padding:8px 12px;font-size:18px}.brand-name{color:var(--text);font-size:15px;font-weight:650}.topbar-right{align-items:center;gap:18px;display:flex}.topbar-stats{gap:18px;display:flex}.stat{text-align:center;line-height:1.1}.stat-num{font-size:20px;font-weight:700;display:block}.stat-label{color:var(--text-dim);text-transform:uppercase;letter-spacing:.6px;font-size:11px}.user-menu{align-items:center;gap:8px;display:flex}.user-avatar{border:1px solid var(--border);object-fit:cover;border-radius:50%;width:28px;height:28px}.signout-btn{font:inherit;color:var(--text-dim);border:1px solid var(--border);cursor:pointer;background:0 0;border-radius:8px;padding:5px 10px;font-size:12px}.signout-btn:hover{color:var(--text);border-color:var(--accent)}#view{flex:1;padding:8px 0 40px}#footer{color:var(--text-dim);text-align:center;border-top:1px solid var(--border);padding:16px 4px 24px;font-size:12px}.card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);margin-bottom:16px;padding:22px}h1{margin-bottom:10px;font-size:26px;line-height:1.25}h2{margin-bottom:12px;font-size:19px}h3{color:var(--text-dim);text-transform:uppercase;letter-spacing:.6px;margin-bottom:12px;font-size:15px}p{color:var(--text-dim);margin-bottom:12px}p.lead{color:var(--text);font-size:16px}.muted{color:var(--text-dim)}.small{font-size:13px}.btn{font:inherit;color:#06121f;background:var(--accent);cursor:pointer;border:none;border-radius:10px;justify-content:center;align-items:center;gap:8px;padding:13px 20px;font-size:15px;font-weight:650;text-decoration:none;transition:transform 50ms,filter .15s;display:inline-flex}.btn:hover{filter:brightness(1.08)}.btn:active{transform:translateY(1px)}.btn.secondary{background:var(--surface-2);color:var(--text);border:1px solid var(--border)}.btn.ghost{color:var(--text-dim);border:1px solid var(--border);background:0 0;font-weight:550}.btn.block{width:100%;display:flex}.btn.lg{padding:16px 22px;font-size:16px}.btn-row{flex-wrap:wrap;gap:10px;display:flex}.btn:disabled{opacity:.5;cursor:default}.hero{text-align:left}.hero .pill{color:var(--accent);background:var(--accent-soft);border-radius:999px;margin-bottom:14px;padding:4px 10px;font-size:12px;font-weight:650;display:inline-block}.action-grid{grid-template-columns:1fr 1fr;gap:12px;margin-top:6px;display:grid}@media (max-width:520px){.action-grid{grid-template-columns:1fr}}.action-tile{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);cursor:pointer;flex-direction:column;gap:4px;padding:18px;transition:border-color .15s,transform 50ms;display:flex}.action-tile:hover{border-color:var(--accent)}.action-tile:active{transform:translateY(1px)}.action-tile .t-title{align-items:center;gap:8px;font-size:16px;font-weight:700;display:flex}.action-tile .t-sub{color:var(--text-dim);font-size:13px}.action-tile.disabled{opacity:.45;cursor:default}.action-tile.disabled:hover{border-color:var(--border)}.badge-count{background:var(--accent);color:#06121f;border-radius:999px;margin-left:auto;padding:1px 8px;font-size:12px;font-weight:800}.mastery-list{flex-direction:column;gap:11px;display:flex}.mastery-row{grid-template-columns:1fr auto;align-items:center;gap:8px 12px;display:grid}.mastery-name{font-size:14px}.mastery-pct{color:var(--text-dim);font-variant-numeric:tabular-nums;font-size:13px}.mastery-track{background:var(--surface-2);border-radius:999px;grid-column:1/-1;height:8px;overflow:hidden}.mastery-fill{border-radius:999px;height:100%;transition:width .4s}.mastery-fill.weak{background:var(--bad)}.mastery-fill.mid{background:var(--warn)}.mastery-fill.strong{background:var(--good)}.mastery-fill.none{background:var(--border)}.tag-weak{color:var(--bad);text-transform:uppercase;letter-spacing:.5px;margin-left:8px;font-size:11px;font-weight:700}.cat-drill{cursor:pointer}.session-head{align-items:center;gap:12px;margin-bottom:18px;display:flex}.progress-track{background:var(--surface-2);border-radius:999px;flex:1;height:6px;overflow:hidden}.progress-fill{background:var(--accent);border-radius:999px;height:100%;transition:width .3s}.session-count{color:var(--text-dim);font-variant-numeric:tabular-nums;white-space:nowrap;font-size:13px}.cat-label{color:var(--accent);text-transform:uppercase;letter-spacing:.6px;margin-bottom:10px;font-size:12px;font-weight:650}.qtype-hint{color:var(--text-dim);margin-bottom:6px;font-size:13px}.stem{color:var(--text);margin:6px 0 22px;font-size:20px;line-height:1.6}.blank{border-bottom:2px solid var(--accent);text-align:center;color:#0000;min-width:64px;margin:0 2px;display:inline-block}.blank.filled{color:var(--accent);border-bottom-color:var(--text-dim);font-weight:650}.uline{border-bottom:2px solid var(--text-dim);cursor:pointer;padding:1px 2px;position:relative}.choices{flex-direction:column;gap:10px;display:flex}.choice{text-align:left;background:var(--surface-2);border:1.5px solid var(--border);font:inherit;color:var(--text);cursor:pointer;border-radius:11px;align-items:center;gap:12px;padding:14px 16px;font-size:16px;transition:border-color .12s,background .12s;display:flex}.choice:hover:not(.locked){border-color:var(--accent)}.choice .key{background:var(--bg);border:1px solid var(--border);width:26px;height:26px;color:var(--text-dim);border-radius:7px;flex:none;place-items:center;font-size:13px;font-weight:700;display:grid}.choice.correct{border-color:var(--good);background:var(--good-soft)}.choice.correct 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6px;font-family:inherit;font-size:12px}.link{color:var(--accent);cursor:pointer;text-decoration:none}.link:hover{text-decoration:underline}.center{text-align:center}.mt{margin-top:16px}.signin-wrap{flex-direction:column;justify-content:center;gap:14px;max-width:460px;min-height:100vh;margin:0 auto;padding:0 16px;display:flex}.signin-card{text-align:center;flex-direction:column;align-items:center;gap:6px;display:flex}.signin-card .brand-mark.lg{margin-bottom:8px}.signin-card form{width:100%;margin-top:12px}.google-btn{color:#1f1f1f;background:#fff;width:100%}.g-mark{color:#4285f4;font-weight:800}