/* 通用设置 */
body {
    font-family: 'Arial', sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f4f4f4;
}

header {
    background-color: #4CAF50;
    color: white;
    padding: 20px;
    text-align: center;
    font-size: 2em;
}

main {
    padding: 20px;
    max-width: 900px;
    margin: 0 auto;
    background-color: #fff;
    border-radius: 10px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

h2, h3 {
    color: #333;
    font-size: 1.5em;
    margin-top: 20px;
}

p {
    color: #555;
    line-height: 1.6;
    font-size: 1em;
    margin: 10px 0;
}

ul {
    list-style-type: disc;
    margin-left: 20px;
}

a {
    color: #4CAF50;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

.video-container {
    position: relative;
    padding-top: 56.25%; /* 16:9 aspect ratio */
    height: 0;
    overflow: hidden;
    max-width: 100%;
    background: #000;
    border-radius: 10px;
    margin-bottom: 20px;
}

video {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border-radius: 10px;
}

.download-info {
    background-color: #f9f9f9;
    border: 1px solid #ddd;
    padding: 15px;
    border-radius: 8px;
    margin-top: 20px;
}

footer {
    text-align: center;
    padding: 10px;
    background-color: #333;
    color: white;
    margin-top: 40px;
}

footer p {
    margin: 0;
}

/* 响应式设计 */
@media (max-width: 768px) {
    header {
        font-size: 1.5em;
    }

    main {
        padding: 15px;
    }

    .video-container {
        padding-top: 75%; /* 4:3 aspect ratio for smaller screens */
    }
}