body {
    font-family: 'PingFang SC', '思源黑体', sans-serif;
    margin: 0;
    padding: 0;
    color: #FFF;
    background-color: #000020;
    display: flex;
    flex-direction: column;
    align-items: center;
    height: 100vh;
    overflow: hidden;
    position: relative;
}
/*
.background {
    position: absolute;
    top: -20%;
    left: 50%;
    width: 150%;
    height: 150%;
    background-image: url('static/img/background.webp');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    transform: translateX(-50%);
    z-index: -1;
}
*/
header {
    width: 100%;
    padding: 20px;
    text-align: center;
    position: absolute;
    top: 2%; /* 调整顶部距离 */
    z-index: 10;
}
header h1 {
    margin: 0;
    font-size: 2.5em;
    color: #FFF;
}
nav {
    margin-top: 6px;
    display: flex;
    justify-content: center;
    align-items: center;
}
nav a {
    text-decoration: none;
    color: #99AABB;
    font-weight: 600;
    font-size: 1.2em;
    position: relative;
    padding: 0 15px;
    z-index: 11;
    transition: color 0.3s;
}
nav a:hover {
    color: #FFF;
}
nav a:not(:last-child)::after {
    content: "";
    height: 0.6em;
    width: 1px;
    background-color: #EEE;
    position: absolute;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
}
.center-wrapper {
    display: flex;
    justify-content: center;
    width: 100%;
}
.center-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    text-align: center;
    position: relative;
    padding-top: 10px;
    z-index: 1;
}
.center-content img {
    width: auto;
    height: 1200px;
    position: absolute;
    top: 115px; /* 固定位置 */
    left: 50%;
    transform: translateX(-50%);
    filter: drop-shadow(0 4px 32px rgba(40, 50, 80, 0.2));
    z-index: 2;
}