*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}


body{
    background-image: linear-gradient(120deg, #ffda62 0%, #72b8fd 100%) ;
    min-height: 100vh;
}
header  {
    background-color: #061b1d;
    width: 100%;
    height: 80px;
    position: fixed;
    z-index: 10;
}
header h1 {
    color:rgb(255, 255, 255);
    /* position: absolute; */
    left: 5px;
    top: 0;
    line-height: 80px;
}
header ul {
    position: absolute;
    right:5vw;
    top: 0;
    line-height: 80px;
}
header li {
    display: inline;
    margin-left: 4vw;
    font-size: 17px;
}
header a {
    color: rgb(255, 255, 255);
    text-decoration: none;
}
header a:hover {
    text-decoration: underline;
}
#mobile-arrow {
    position: absolute;
    left: 20px; /* 将箭头移到左边 */
    top: 50%;
    transform: translateY(-50%);
    color: white;
    font-size: 36px; /* 放大字体，可按需调整 */
    text-decoration: none;
}

#mobile-arrow:hover {
    color: #ccc;
}
footer{
    /* background-color: rgb(32, 32, 32); */
    color: rgb(133, 133, 133);
    height: 30px;
    /* display: flex;
    justify-content: center;
    align-items: center;
    line-height: 1.8em; */
    font-size: 10px;
    position: fixed;
    left:40%;
    bottom: 0px;

}


.square-container {
    display: flex;
    justify-content: center; /* 水平居中 */
    flex-wrap: wrap; /* 当空间不足时换行 */
    gap: 10px; /* 框框之间的间距 */
}
.rounded-square {
    width: 160px; /* 正方形的宽度 */
    height: 160px; /* 正方形的高度 */
    border-radius: 10px; /* 圆角半径，值越大圆角越明显 */
    background-color: #e4e4e4; /* 框框的背景颜色，可按需修改 */
    margin: 10px; /* 框框之间的外边距 */
    display: inline-block; /* 让框框水平排列 */
    vertical-align: top; 
    padding: 15px; 
    box-sizing: border-box; 
    text-align: center; /* 文本水平居中 */
}

.jieshao {
    display: flex;
    flex-direction: column; 
    align-items: center;
    justify-content: center; /* 垂直方向居中 */
    text-align: center; /* 文本水平居中 */
}


/* 时间线容器 */
.timeline {
    position: relative;
    max-width: 1200px;
    margin: 0 auto;
}

/* 时间线垂直线 */
.timeline::after {
    content: '';
    position: absolute;
    width: 6px;
    background-color: #ccc;
    top: 0;
    bottom: 0;
    left: 50%;
    margin-left: -3px;
}

/* 时间线项目 */
.timeline-item {
    padding: 10px 40px;
    position: relative;
    background-color: inherit;
    width: 50%;
}

/* 时间线项目的圆形标记 */
.timeline-item::after {
    content: '';
    position: absolute;
    width: 25px;
    height: 25px;
    right: -13px;
    background-color: white;
    border: 4px solid #FF9F55;
    top: 15px;
    border-radius: 50%;
    z-index: 1;
}

/* 左半部分的时间线项目 */
.timeline-item.left {
    left: 0;
}

/* 右半部分的时间线项目 */
.timeline-item.right {
    left: 50%;
}

/* 右半部分时间线项目的圆形标记位置调整 */
.timeline-item.right::after {
    left: -13px;
}

/* 时间日期样式 */
.timeline-date {
    padding: 10px;
    background-color: #FF9F55;
    color: white;
    border-radius: 6px;
    margin-bottom: 10px;
    display: inline-block;
}

/* 时间内容样式 */
.timeline-content {
    padding: 20px 30px;
    background-color: white;
    position: relative;
    border-radius: 6px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

@media (max-width: 600px) {
    .item-name {
        margin-left: 10px;
    }
    .item-type {
        margin-left: 10px;
    }
    .download-button {
        margin-right: 30px; 
    
    }
    footer {
        left:20%;
    }
}