:root{--bg-primary:#fff;--bg-secondary:#f4f4f5;--bg-card:#fafafa;--text-primary:#18181b;--text-secondary:#71717a;--text-muted:#a1a1aa;--border:#e4e4e7;--accent:#2563eb;--accent-hover:#1d4ed8;--correct:#16a34a;--incorrect:#dc2626;--correct-bg:#dcfce7;--incorrect-bg:#fee2e2;--pending:#18181b;--timer-normal:#2563eb;--timer-warning:#dc2626;--shadow:0 1px 3px rgba(0,0,0,.08)}[data-theme=dark]{--bg-primary:#09090b;--bg-secondary:#18181b;--bg-card:#27272a;--text-primary:#fafafa;--text-secondary:#a1a1aa;--text-muted:#71717a;--border:#3f3f46;--accent:#3b82f6;--accent-hover:#2563eb;--correct:#22c55e;--incorrect:#ef4444;--correct-bg:#14532d;--incorrect-bg:#7f1d1d;--pending:#fafafa;--timer-normal:#3b82f6;--timer-warning:#ef4444;--shadow:0 1px 3px rgba(0,0,0,.4)}*{margin:0;padding:0;box-sizing:border-box;transition:background-color .2s ease,color .2s ease,border-color .2s ease}body{background-color:var(--bg-primary);color:var(--text-primary);font-family:system-ui,-apple-system,sans-serif;font-size:16px;line-height:1.6}.container{max-width:820px;margin:0 auto;padding:0 16px}@media (min-width:640px){.container{padding:0 24px}}.card{background:var(--bg-card);border:1px solid var(--border);border-radius:8px;padding:20px;box-shadow:var(--shadow)}@media (max-width:640px){.card{padding:14px}.passage-box{max-height:200px;overflow-y:auto;font-size:16px!important;line-height:1.6!important}.typing-textarea{height:80px!important;font-size:16px!important}.passage-input-gap{gap:12px!important}}.btn-primary{background:var(--accent);color:#fff;border:none;border-radius:6px;padding:12px 24px;font-size:16px;cursor:pointer;font-weight:500;font-family:system-ui,-apple-system,sans-serif}.btn-primary:hover{background:var(--accent-hover)}.btn-primary:disabled{background:var(--text-muted);cursor:not-allowed}