/* 主题CSS变量 */
:root {
    --color-primary: #3b82f6;
    --color-secondary: #8b5cf6;
    --color-success: #10b981;
    --color-warning: #f59e0b;
    --color-danger: #ef4444;
    --color-accent: #ec4899;
}

/* 答题游戏样式 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    border-radius: 0.75rem;
    font-weight: 500;
    transition: all 0.2s;
    cursor: pointer;
}

.btn-primary {
    background: var(--color-primary);
    color: white;
    box-shadow: 0 4px 6px -1px rgba(59, 130, 246, 0.25);
}

.btn-primary:hover {
    filter: brightness(0.9);
}

.btn-secondary {
    background: #f3f4f6;
    color: #374151;
}

.btn-secondary:hover {
    background: #e5e7eb;
}

.card-hover {
    transition: all 0.3s ease;
}

.card-hover:hover {
    transform: translateY(-4px);
}

/* 动画 */
@keyframes bounce-in {
    0% { transform: scale(0); opacity: 0; }
    50% { transform: scale(1.2); }
    100% { transform: scale(1); opacity: 1; }
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-5px); }
    75% { transform: translateX(5px); }
}

@keyframes pulse-glow {
    0%, 100% { box-shadow: 0 0 0 0 rgba(59, 130, 246, 0.4); }
    50% { box-shadow: 0 0 0 10px rgba(59, 130, 246, 0); }
}

.animate-bounce-in {
    animation: bounce-in 0.5s ease-out;
}

.animate-shake {
    animation: shake 0.5s ease-in-out;
}

.animate-pulse-glow {
    animation: pulse-glow 2s infinite;
}

/* 答题选项动画 */
.answer-option {
    transition: all 0.2s ease;
}

.answer-option:active {
    transform: scale(0.98);
}

/* 进度条 */
.progress-bar {
    transition: width 0.3s ease;
}

/* 主题渐变 */
.theme-gradient-default {
    background: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);
}

.theme-gradient-tech {
    background: linear-gradient(135deg, #06b6d4 0%, #3b82f6 100%);
}

.theme-gradient-retro {
    background: linear-gradient(135deg, #f97316 0%, #ef4444 100%);
}

.theme-gradient-cute {
    background: linear-gradient(135deg, #ec4899 0%, #a855f7 100%);
}

/* 毛玻璃效果 */
.glass {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
}

/* 连击特效 */
.streak-3 {
    background: linear-gradient(135deg, #f97316 0%, #ea580c 100%);
}

.streak-5 {
    background: linear-gradient(135deg, #ef4444 0%, #dc2626 100%);
}

.streak-10 {
    background: linear-gradient(135deg, #a855f7 0%, #7c3aed 100%);
}

/* 响应式优化 */
@media (max-width: 640px) {
    .btn {
        padding: 0.5rem 1rem;
        font-size: 0.875rem;
    }
}