@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@400;500;700;900&display=swap');
:root { color-scheme: light; }
body { font-family: 'Noto Sans SC', 'Noto Sans SC', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif; }
button { -webkit-tap-highlight-color: transparent; }
.option-btn { transition: all 0.15s ease-out; }
.option-btn:not(:disabled):hover { transform: translateY(-1px); border-color: #6366f1; }
.correct { background-color: #f0fdf4 !important; border-color: #22c55e !important; color: #15803d !important; }
.wrong { background-color: #fef2f2 !important; border-color: #ef4444 !important; color: #b91c1c !important; }
.multi-selected { border-color: #6366f1 !important; background-color: #eef2ff !important; box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.2); }
.animate-fade { animation: fadeIn 0.3s ease-out; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(4px); } to { opacity: 1; transform: translateY(0); } }
.prose-content h1, .prose-content h2, .prose-content h3 { font-weight: 800; margin: 0.5rem 0; color: #1e293b; }
.prose-content p { margin-bottom: 0.5rem; line-height: 1.7; }
.prose-content ul, .prose-content ol { margin-left: 1.5rem; margin-bottom: 0.5rem; }
.prose-content ul { list-style: disc; }
.prose-content ol { list-style: decimal; }
.prose-content strong { color: #4338ca; }
.prose-content code { padding: 0.1rem 0.3rem; border-radius: 0.375rem; background: #e2e8f0; }