body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
}

body:before{
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    opacity: .3;
    z-index: -1;
    content: "";
    position: fixed;
    background: url(https://api.paugram.com/bing/) center/cover;
}

header {
    background-color: #007bff61;
    color: white;
    text-align: center;
    padding: 1em 0;
}

main {
    padding: 2em;
}

.tools-list {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    justify-content: center;
}

.tool-item {
    background-color: white;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    padding: 1.5em;
    width: 300px;
    text-align: center;
}

.tool-item h2 {
    margin-bottom: 0.5em;
}

.tool-item p {
    color: #555;
}

.tool-item a {
    display: inline-block;
    margin-top: 1em;
    background-color: #007BFF;
    color: white;
    padding: 0.5em 1em;
    text-decoration: none;
    border-radius: 4px;
    transition: background-color 0.3s ease;
}

.tool-item a:hover {
    background-color: #0056b3;
}

  footer {
    /* 文本居中对齐 */
    text-align: center;
    /* 内边距，上下10px，左右10px */
    padding: 10px;
    /* 背景颜色，浅灰色 */
    background-color: #f8f9fa;
    /* 顶部外边距，距离上方元素20px */
    margin-top: 10px;
    /* 底部外边距，距离下方元素20px */
    margin-bottom: 10px;   
}