/* 背景样式文件 - 独立分离便于迁移 */

/* 主背景渐变 */
body {
    background: linear-gradient(135deg, 
        #e8f5e8 0%, 
        #f1f8e9 25%, 
        #e8f5e8 50%, 
        #c8e6c9 75%, 
        #e8f5e8 100%);
    background-size: 400% 400%;
    animation: backgroundShift 15s ease-in-out infinite;
    position: relative;
}

/* 背景动画 */
@keyframes backgroundShift {
    0%, 100% {
        background-position: 0% 50%;
    }
    25% {
        background-position: 100% 50%;
    }
    50% {
        background-position: 50% 100%;
    }
    75% {
        background-position: 50% 0%;
    }
}

/* 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% 20%, rgba(76, 175, 80, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(129, 199, 132, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 40% 60%, rgba(165, 214, 167, 0.08) 0%, transparent 50%);
    pointer-events: none;
    z-index: -1;
    animation: floatingBubbles 20s ease-in-out infinite;
}

@keyframes floatingBubbles {
    0%, 100% {
        transform: translateY(0px) rotate(0deg);
        opacity: 1;
    }
    33% {
        transform: translateY(-20px) rotate(120deg);
        opacity: 0.8;
    }
    66% {
        transform: translateY(10px) rotate(240deg);
        opacity: 0.9;
    }
}

/* 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;
    pointer-events: none;
    z-index: -1;
    animation: particleFloat 25s linear infinite;
}

@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: 20s;
    }
    
    body::before {
        animation-duration: 15s;
    }
}

@media (max-width: 480px) {
    body::after {
        background-size: 100px 50px;
        animation-duration: 15s;
    }
    
    body::before {
        animation-duration: 12s;
    }
    
    body {
        animation-duration: 12s;
    }
}

/* 高性能模式 - 减少动画 */
@media (prefers-reduced-motion: reduce) {
    body,
    body::before,
    body::after {
        animation: none;
    }
    
    body {
        background: linear-gradient(135deg, #e8f5e8 0%, #f1f8e9 50%, #c8e6c9 100%);
    }
}