/* 背景样式文件 */
body {
    background: linear-gradient(135deg, #E8F5E8 0%, #F1F8E9 25%, #E0F2F1 50%, #E8F5E8 75%, #F3E5F5 100%);
    background-size: 400% 400%;
    animation: gradientShift 15s ease infinite;
    position: relative;
}

/* 背景渐变动画 */
@keyframes gradientShift {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

/* 背景装饰元素 */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(circle at 20% 80%, rgba(76, 175, 80, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(129, 199, 132, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 40% 40%, rgba(165, 214, 167, 0.08) 0%, transparent 50%);
    pointer-events: none;
    z-index: -2;
}

/* 背景粒子效果 */
body::after {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(2px 2px at 20px 30px, rgba(76, 175, 80, 0.3), transparent),
        radial-gradient(2px 2px at 40px 70px, rgba(129, 199, 132, 0.2), transparent),
        radial-gradient(1px 1px at 90px 40px, rgba(165, 214, 167, 0.3), transparent),
        radial-gradient(1px 1px at 130px 80px, rgba(76, 175, 80, 0.2), transparent),
        radial-gradient(2px 2px at 160px 30px, rgba(129, 199, 132, 0.3), transparent);
    background-repeat: repeat;
    background-size: 200px 100px;
    animation: particleFloat 20s linear infinite;
    pointer-events: none;
    z-index: -1;
    opacity: 0.6;
}

@keyframes particleFloat {
    0% {
        transform: translateY(0px);
    }
    100% {
        transform: translateY(-100px);
    }
}

/* 响应式背景调整 */
@media (max-width: 768px) {
    body::after {
        background-size: 150px 75px;
        animation-duration: 25s;
    }
}

@media (max-width: 480px) {
    body::after {
        background-size: 100px 50px;
        animation-duration: 30s;
        opacity: 0.4;
    }
}

/* 高性能模式 - 减少动画 */
@media (prefers-reduced-motion: reduce) {
    body {
        animation: none;
        background: linear-gradient(135deg, #E8F5E8 0%, #F1F8E9 50%, #E0F2F1 100%);
    }
    
    body::after {
        animation: none;
    }
    
    .title {
        animation: none;
    }
}

/* 深色模式支持 */
@media (prefers-color-scheme: dark) {
    body {
        background: linear-gradient(135deg, #1B5E20 0%, #2E7D32 25%, #388E3C 50%, #43A047 75%, #4CAF50 100%);
    }
    
    body::before {
        background-image: 
            radial-gradient(circle at 20% 80%, rgba(255, 255, 255, 0.05) 0%, transparent 50%),
            radial-gradient(circle at 80% 20%, rgba(255, 255, 255, 0.03) 0%, transparent 50%),
            radial-gradient(circle at 40% 40%, rgba(255, 255, 255, 0.02) 0%, transparent 50%);
    }
    
    body::after {
        background-image: 
            radial-gradient(1px 1px at 20px 30px, rgba(255, 255, 255, 0.1), transparent),
            radial-gradient(1px 1px at 40px 70px, rgba(255, 255, 255, 0.08), transparent),
            radial-gradient(1px 1px at 90px 40px, rgba(255, 255, 255, 0.06), transparent),
            radial-gradient(1px 1px at 130px 80px, rgba(255, 255, 255, 0.04), transparent),
            radial-gradient(1px 1px at 160px 30px, rgba(255, 255, 255, 0.05), transparent);
        opacity: 0.3;
    }
}