:root{--bg:#0f1117;--surface:#1a1d27;--surface2:#22263a;--border:#2e3248;--text:#e2e8f0;--text-muted:#8892a4;--accent:#3b82f6;--accent-hover:#2563eb;--correct:#22c55e;--correct-bg:#22c55e1f;--incorrect:#ef4444;--incorrect-bg:#ef44441f;--missed:#fbbf2426;--flag:#f59e0b;--flag-bg:#f59e0b26;--radius:10px;--shadow:0 4px 24px #0006;--mobile-nav-h:60px}html,body{background:var(--bg);height:100%;color:var(--text);-webkit-text-size-adjust:100%;font-family:Segoe UI,system-ui,-apple-system,sans-serif;font-size:16px;line-height:1.6}.pin-screen{background:radial-gradient(ellipse at 50% 0%, #1a1e3a 0%, var(--bg) 70%);justify-content:center;align-items:center;min-height:100vh;padding:16px;display:flex}.pin-card{background:var(--surface);border:1px solid var(--border);text-align:center;box-shadow:var(--shadow);border-radius:20px;width:100%;max-width:420px;padding:44px 48px}.pin-logo{margin-bottom:12px;font-size:48px}.pin-card h1{margin-bottom:6px;font-size:1.8rem;font-weight:700}.pin-subtitle{color:var(--text-muted);margin-bottom:28px;font-size:.92rem}.pin-form{flex-direction:column;gap:16px;display:flex}.pin-input-wrap{position:relative}.pin-input{background:var(--surface2);border:2px solid var(--border);border-radius:var(--radius);width:100%;color:var(--text);letter-spacing:.05em;text-align:center;outline:none;padding:14px 18px;font-size:1.05rem;transition:border-color .2s}.pin-input:focus{border-color:var(--accent)}.pin-input-wrap.error .pin-input{border-color:var(--incorrect)}.pin-error{color:var(--incorrect);font-size:.88rem}@keyframes shake{0%,to{transform:translate(0)}20%,60%{transform:translate(-8px)}40%,80%{transform:translate(8px)}}.pin-input-wrap.shake{animation:.4s shake}.start-screen{background:radial-gradient(ellipse at 50% 0%, #1e2a50 0%, var(--bg) 70%);justify-content:center;align-items:center;min-height:100vh;padding:16px;display:flex}.start-card 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