.math-board { text-align: center; max-width: 360px; }
.question { font-family: var(--font-display, Fredoka, sans-serif); font-size: clamp(2rem, 10vw, 3rem); font-weight: 700; color: #C2410C; margin-bottom: 1.5rem; }
.choices { display: grid; grid-template-columns: repeat(2, 1fr); gap: 0.75rem; }
.choice-btn { min-height: 64px; border: none; border-radius: 16px; background: linear-gradient(135deg, #FB923C, #EA580C); color: #fff; font-size: 1.5rem; font-weight: 800; cursor: pointer; box-shadow: 0 4px 14px rgba(234, 88, 12, 0.35); transition: transform 0.15s; }
.choice-btn:hover { transform: scale(1.04); }
.choice-btn.wrong { background: #EF4444; animation: shake 0.4s; }
@keyframes shake { 0%,100%{transform:translateX(0)} 25%{transform:translateX(-6px)} 75%{transform:translateX(6px)} }