/* 下雪效果样式 - 圆球模糊晕染效果 */
#snow-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 9999;
    overflow: hidden;
}

.snowflake {
    position: absolute;
    top: -20px;
    width: 10px;
    height: 10px;
    background: radial-gradient(circle, rgba(255, 255, 255, 1) 0%, rgba(255, 255, 255, 0.9) 30%, rgba(255, 255, 255, 0.6) 60%, rgba(255, 255, 255, 0) 100%);
    border-radius: 50%;
    pointer-events: none;
    user-select: none;
    box-shadow: 
        0 0 10px rgba(255, 255, 255, 0.8),
        0 0 20px rgba(255, 255, 255, 0.6),
        0 0 30px rgba(255, 255, 255, 0.4),
        inset 0 0 10px rgba(255, 255, 255, 0.5);
    filter: blur(1px);
    will-change: transform;
}

/* 下落动画 */
@keyframes falling {
    0% {
        transform: translateY(0) translateX(0) rotate(0deg);
    }
    100% {
        transform: translateY(calc(100vh + 40px)) translateX(50px) rotate(360deg);
    }
}

/* 雪花摆动效果 - 更自然的左右晃动 */
.snowflake:nth-child(3n) {
    animation: falling linear infinite, swaying 3s ease-in-out infinite;
}

.snowflake:nth-child(3n+1) {
    animation: falling linear infinite, swaying-reverse 4s ease-in-out infinite;
}

.snowflake:nth-child(3n+2) {
    animation: falling linear infinite, swaying-medium 3.5s ease-in-out infinite;
}

@keyframes swaying {
    0%, 100% {
        margin-left: 0;
    }
    25% {
        margin-left: 15px;
    }
    75% {
        margin-left: -15px;
    }
}

@keyframes swaying-reverse {
    0%, 100% {
        margin-left: 0;
    }
    25% {
        margin-left: -20px;
    }
    75% {
        margin-left: 20px;
    }
}

@keyframes swaying-medium {
    0%, 100% {
        margin-left: 0;
    }
    50% {
        margin-left: 25px;
    }
}

/* 不同大小的雪花 */
.snowflake.small {
    width: 6px;
    height: 6px;
    filter: blur(0.5px);
}

.snowflake.medium {
    width: 10px;
    height: 10px;
    filter: blur(1px);
}

.snowflake.large {
    width: 14px;
    height: 14px;
    filter: blur(1.5px);
    box-shadow: 
        0 0 15px rgba(255, 255, 255, 0.9),
        0 0 25px rgba(255, 255, 255, 0.7),
        0 0 35px rgba(255, 255, 255, 0.5),
        inset 0 0 15px rgba(255, 255, 255, 0.6);
}