body, html {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    background-color: black;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; /* 设置字体 */
    background-color: #f0f2f5;
}

video {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 100vw;
    height: 100vh;
    object-fit: cover;
    transform: translate(-50%, -50%);
}

@media (max-width: 768px) {
    video {
        width: 100%;
        height: auto;
    }
}

@media (min-width: 769px) {
    video {
        width: 100vw;
        height: 100vh;
    }
}