* {
    box-sizing: border-box;
}
body {
margin: 0;
}
/* 样式化顶部导航栏 */
.navbar {
    overflow: hidden;
    background-color: #333;
    border-radius: 15px;
    font-size: 16px;
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 5;
}
/* 样式化导航栏链接 */
.navbar a {
    float: left;
    display: block;
    color: white;
    text-align: center;
    padding: 14px 16px;
    text-decoration: none;
}
/* 右对齐链接 */
.navbar a.right {
    float: right;
}
/* 悬停时改变颜色 */
.navbar a:hover {
    background-color: rgb(60,180,230);
    color: black;
}

/* 固定侧导航，全高 */
.sidenav {
height: 85%;
width: 200px;
position: fixed;
top: 0;
left: 30px;
background-color: #ffffff;
overflow-y: auto;
margin-top: 100px;
margin-bottom: 100px;
}
/* 设置 sidenav 链接和下拉按钮的样式 */
.sidenav a, .dropdown-btn {
padding: 6px 8px 6px 16px;
text-decoration: none;
font-size: 18px;
color: #707070;
display: block;
border: none;
background: none;
width:100%;
text-align: left;
cursor: pointer;
outline: none;
}

/* 鼠标悬停 */
.sidenav a:hover, .dropdown-btn:hover {
color: #000000;
background-color: #ddd;
}

/* 添加一个活动类到活动下拉按钮 */
.active {
background-color: rgb(114, 114, 114);
color: white;
}

/* 下拉容器（默认隐藏）。 可选:添加较浅的背景颜色和一些左侧填充以更改下拉内容的设计 */
.dropdown-container {
display: none;
background-color: #ffffff;
padding-left: 8px;
}

/* 可选:设置插入符号图标的样式 */
.fa-caret-down {
float: right;
padding-right: 8px;
}

.main {

    font-size: 17px;
    flex: 80%;
    margin-left: 20%;
    margin-right: 10%;
    margin-top: 80px;
    line-height: 25px;
    font-weight: 500;
}
.main p {margin:10px 0 0 0;}
.main h5 {
    font-size: 20px;
    margin: 10px 0;
}
.main h4{
    font-size: 20px;
    color: red;
    font-weight: 500;
    margin: 10px 0;
}
.main h3{
    font-size: 20px;
    color: #2c77da;
    font-weight: 500;
    margin: 10px 0;
}
.main a {
color:#219adb;
text-underline-offset: 0.35em;
}
.main img {
    max-width: 100%;
    max-height: 900px;
}
.main details{
    margin:12px 0 12px 0;
    color: rgb(40,44,52);
}
.main hr {margin-top: 40px;}

.br {/*没有实际意义了，纯兼容*/
    display: none;
}
.red{
    color: red;
    font-size: 20px;
}
.blue{
    color: #2c77da;
    font-size: 20px;
}

.code{
    font-size: 20px;
    /* 设置内容区域的字体大小 */
}
.code pre{
    font-size: 17px;
    position: relative;
    line-height: 22px;
}
pre .btn-pre-copy{
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    -khtml-user-select: none;
    user-select: none;
    position: absolute;
    top: 10px;
    right: 12px;
    font-size: 25px;
    line-height: 1;
    cursor: pointer;
    color: #fff;
    transition: color .1s;
    padding: 8px;
    border-radius: 8px;
    /* 设置复制按钮的样式 */
}
pre .btn-pre-copy:hover{
    background-color: #23a8f2;
}

.footer {
padding: 20px;
text-align: center;
background: #ddd;
}

@media screen and (max-width: 1000px) {
.main {   
    margin-left: 2%;
    margin-right: 2%;
    margin-top: 60px;
}
.main img {max-width: 100%;}
.sidenav {display: none;}
.br {display: none;}/*没有实际意义了，纯兼容*/
}