/* 第一层星星 - 固定闪烁 */
.star-layer-1 {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 10;
}

.star-1 {
    position: absolute;
    background-color: white;
    border-radius: 50%;
    animation: twinkle linear infinite;
}

/* 第二层星星 - 随页面滚动 */
.star-layer-2 {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 5;
}

.star-2 {
    position: absolute;
    background-color: white;
    border-radius: 50%;
    animation: moveAndFade linear infinite;
}

/* 第三层星星 - 星轨效果 */
.star-layer-3 {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 15;
}

.star-trail {
    position: absolute;
    width: 3px;
    height: 3px;
    border-radius: 50%;
    background-color: white;
    box-shadow: 0 0 3px 1px rgba(255, 255, 255, 0.8);
    animation: orbit linear infinite;
}

/* 动画定义 */
@keyframes twinkle {
    0%, 100% { opacity: 0; }
    50% { opacity: 1; }
}

@keyframes moveAndFade {
    0%, 100% {
        transform: translate(0, 0);
        opacity: 0.4;
    }
    25% {
        transform: translate(10px, -5px);
        opacity: 1;
    }
    50% {
        transform: translate(-8px, 7px);
        opacity: 0.6;
    }
    75% {
        transform: translate(5px, 10px);
        opacity: 0.8;
    }
}

@keyframes orbit {
    from {
        transform: rotate(0deg) translateX(150px) rotate(0deg);
    }
    to {
        transform: rotate(360deg) translateX(150px) rotate(-360deg);
    }
}