:root{--bg: #0b0b0b;--card: #0f1113;--muted: #9aa4b2;--text: #e6eef6;--border: #202428;--accent: #58a6ff;--success: #2ea043;--danger: #f85149;--glass: rgba(255,255,255,.03)}body.light{--bg: #f6f8fa;--card: #ffffff;--text: #0b0b0b;--muted: #606770;--border: #d7dde6;--accent: #0969da}*{box-sizing:border-box}body{background:var(--bg);color:var(--text);font-family:Inter,system-ui,-apple-system,Segoe UI,Roboto,Helvetica Neue,Arial;margin:0;min-height:100vh;-webkit-font-smoothing:antialiased;display:flex;flex-direction:column;align-items:center}.loading-overlay{position:fixed;inset:0;display:flex;align-items:center;justify-content:center;background:linear-gradient(0deg,#0009,#0009);z-index:1200;transition:opacity .36s ease}.loading-overlay.hidden{pointer-events:none;opacity:0;visibility:hidden}.loading-inner{text-align:center;color:var(--text)}.blob{width:120px;height:120px;border-radius:48% 52% 65% 35%/45% 35% 65% 55%;background:radial-gradient(circle at 30% 20%,rgba(88,166,255,.12),transparent),linear-gradient(135deg,#58a6ff1f,#2ea04314);filter:blur(12px);margin:0 auto 14px;animation:blob-morph 4.2s infinite ease-in-out;box-shadow:0 12px 40px #0009,0 2px 10px #2ea0430f}.loading-text{font-weight:600;font-size:1rem;margin-top:6px;color:var(--text)}.loading-sub{font-size:.85rem;color:var(--muted);margin-top:6px}@keyframes blob-morph{0%{transform:translateY(0) scale(1);border-radius:42% 58% 61% 39%/41% 34% 66% 59%}33%{transform:translateY(-8px) scale(1.03);border-radius:50% 40% 60%/60% 30% 70% 40%}66%{transform:translateY(4px) scale(.98);border-radius:60% 40% 40% 60%/30% 60% 40% 70%}to{transform:translateY(0) scale(1);border-radius:42% 58% 61% 39%/41% 34% 66% 59%}}.app-root{width:100%;max-width:1200px;padding:24px}.app-root.hidden{display:none}.app-header{display:flex;justify-content:space-between;align-items:center;width:100%;margin-bottom:18px}.brand h1{margin:0;font-size:1.1rem;color:var(--accent)}.brand .tag{margin:0;color:var(--muted);font-size:.85rem}.header-controls{display:flex;gap:10px;align-items:center}.xp{padding:8px 12px;background:var(--card);border:1px solid var(--border);border-radius:10px;color:var(--text);font-weight:600}.icon-btn{background:transparent;border:1px solid var(--border);color:var(--text);padding:8px;border-radius:10px;cursor:pointer}.progress-zone{width:100%;display:flex;justify-content:center;margin-bottom:18px}.progress-card{width:100%;max-width:1100px;background:transparent;padding:2px 8px;border-radius:10px}.progress-meta{display:flex;justify-content:space-between;align-items:center;margin-bottom:8px;color:var(--muted);font-size:.9rem}.progress-track{height:8px;background:var(--border);border-radius:999px;overflow:hidden}.progress-bar{height:100%;width:0%;background:linear-gradient(90deg,var(--accent),var(--success));transition:width .42s ease;border-radius:999px}.main-grid{width:100%;display:grid;grid-template-columns:1fr 320px;gap:18px;align-items:start}.challenge-panel{background:linear-gradient(180deg,#ffffff05,#ffffff03);border:1px solid var(--border);padding:16px;border-radius:12px;box-shadow:0 6px 30px #00000073}.challenge-header{display:flex;justify-content:space-between;align-items:center;gap:12px;margin-bottom:8px}.challenge-title{font-size:1.05rem;font-weight:700;color:var(--accent)}.challenge-category{color:var(--muted);font-size:.9rem}.challenge-description{color:var(--muted);margin:8px 0 12px}.level-controls{display:flex;gap:8px;margin-bottom:12px}.level-btn{flex:1;padding:8px 10px;border-radius:8px;border:1px solid var(--border);background:linear-gradient(180deg,#ffffff03,#00000008);color:var(--text);cursor:pointer;font-weight:600;transition:transform .16s ease,box-shadow .16s ease}.level-btn:hover{transform:translateY(-3px)}.level-btn.locked{opacity:.45;cursor:not-allowed;transform:none;filter:grayscale(.2)}.level-btn.passed{box-shadow:0 8px 30px 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rgba(255,255,255,.03)}.feedback{margin-top:10px;font-weight:700;min-height:20px}.console{margin-top:10px;max-height:130px;overflow:auto;border-radius:8px;border:1px solid rgba(255,255,255,.02);padding:8px;background:linear-gradient(180deg,rgba(255,255,255,.01),transparent);color:var(--muted);font-size:.9rem}.console-line{padding:6px 4px;border-bottom:1px dashed rgba(255,255,255,.02)}.console-line.success{color:var(--success)}.console-line.error{color:var(--danger)}.console-line.meta{color:var(--muted)}.insight{margin-top:12px;color:var(--accent);font-size:.92rem}.bp-block{background:#ffffff05;padding:10px;border-radius:8px;color:var(--text);max-height:220px;overflow:auto}.sidebar{display:flex;flex-direction:column;gap:12px}.sidecard{background:var(--card);border:1px solid var(--border);padding:12px;border-radius:10px;color:var(--muted)}.sidecard h3{margin:0 0 6px;color:var(--accent);font-size:.95rem}.small-muted{color:var(--muted);font-size:.88rem}.app-footer{margin-top:18px;width:100%;max-width:1200px;display:flex;justify-content:space-between;color:var(--muted);font-size:.9rem}.done{padding:18px;text-align:center;color:var(--accent);font-weight:700}.error{color:var(--danger);background:#f8514905;padding:8px;border-radius:8px;border:1px solid rgba(248,81,73,.06)}@media (max-width: 980px){.main-grid{grid-template-columns:1fr;padding:8px}.sidebar{order:2}}pre{font-family:JetBrains Mono,monospace;font-size:.9rem;white-space:pre-wrap;word-break:break-word}