html {
    height: 100%;
    overflow-x: hidden;
}

body {
    /* 确保有足够的滚动空间 */
    position: relative;
}

/* 视差背景层 - 关键样式 */
.parallax-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    z-index: -1;
}

.parallax-bg img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: auto;
    min-height: 100%;
    object-fit: cover;
    transform: translateY(0);
    will-change: transform;
    transition: filter 0.3s ease;
}

/* 深蓝色覆盖层 */
.parallax-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
    pointer-events: none;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.parallax-overlay.dark-mode {
    opacity: 1;
    background-color: rgba(25, 40, 70, 0.6);
    /* 深蓝色，60%透明度 */
}