body {
    margin: 0;
    padding: 0;
    background-image: linear-gradient(to right, #fbc2eb, #a6c1ee);
    font-family: Arial, sans-serif;
}
a{
    text-decoration: none;
}
header {
    text-align: center;
    margin-bottom: 20px;
}
.header-image {
    width: 100%;
    max-width: 150px;
    height: auto;
    border-radius: 8px;
}
.preface {
    height: 200px;
    display: block;
    text-align: center; /* 使标题居中 */
}
.preface h1 {
    margin: 0; /* 移除标题的默认外边距 */
    padding: 20px 0; /* 可以根据需要调整上下内边距 */
    text-align: center; /* 使标题在盒子内居中 */
}
.preface p {
    text-indent: 2em; /* 首行缩进 2 个字符 */
    padding: 0 20px; /* 可以根据需要调整左右内边距 */
    text-align: center; /* 使标题居中 */
}
.big-box {
    height: 360px;
    display: inline-block;
    width: calc(50% - 9%); /* 调整宽度以适应两个盒子 */
    margin: 0 2.5% 20px; /* 保持左右边距 */
    padding: 20px;
    background-color: #f5f5f5;
    border-radius: 16px;
    vertical-align: top;
}
.title-box {
    background-color: #333;
    color: white;
    padding: 10px 20px;
    border-radius: 8px;
    text-align: center;
    margin-bottom: 20px;
}
.small-box {
    padding: 20px;
    background-color: #ffffff;
    border-radius: 12px;
}
ul {
    list-style-type: none;
    padding: 0;
}
li {
    border: 1px solid #ddd; /* Add a border to each list item */
    padding: 10px; /* Add some padding inside the list item */
    border-radius: 6px; /* Optional: rounded corners for the list items */
    margin-bottom: 10px;
    box-sizing: border-box; /* This ensures that the padding and border are included in the width and height */
    transition: background-color 0.3s ease;
}
li:hover {
    background-color: #f0f0f0; /* Change to a darker color when hovered */
}