body,
div {
    margin: 0;
    padding: 0;
}

.coverbody {
    /* background: url("../images/bg3.jpg") repeat-x scroll 0 0 #67ACE4; */
    /* background: url("../images/bg2.jpg") repeat-x scroll 0 0; */
    background: url("../images/bg2.jpg");
}

#container {
    margin: 0 auto;
    padding-top: 50px;
    /* text-align: center; */
    width: 1000px;
}

#container img {
    border: medium none;
    margin-bottom: 50px;
}

#container .error {
    height: 200px;
    position: relative;
}

#container .error img {
    bottom: -50px;
    position: absolute;
    right: -50px;
}

#container .msg {
    margin-bottom: 65px;
}

.convernote {
    font-family: "microsoft yahei";
    font-size: 25px;
    color: greenyellow;
}

.covercontent {
    font-family: "microsoft yahei";
    font-size: 20px;
    color: white;
}

/*文字显示在右边*/
.right {
    position: relative;
    /* 相对于原始位置进行定位 */
    left: 100%;
    /* 左移100%，使得元素超出视口 */
    transform: translateX(-30%);
    /* 水平居中 */
}

/*图片居中*/
.imgcenter {
    display: block;
    /* 转换成块级元素 */
    margin: auto;
    /* 自动计算左右边距，达到居中效果 */
}

.imageright {
    float: right;
    /* 或者 text-align: right; */
}

/*树形菜单*/
#lefttreemenu {
    position: fixed;
    /* background: #007AFF; */
    width: 450px;
    height: 500px;
}

details {
    padding-left: 20px
}

summary {
    list-style: none;
}

summary:before {
    content: "";
    color: #696f7c;
    margin-right: 5px;
    padding: 10px;
}

summary:not(:only-child) {
    background: url("../images/rightarrow1.png") 4px center no-repeat;
}

summary:only-child {
    background: url("../images/point1.png") 4px center no-repeat;
}

details[open]>summary:not(:only-child) {
    background-image: url("../images/downarrow1.png");
}

.tree-item:hover {
    background: #8CC38250;
    padding-left: 400px;
    margin-left: -400px;
}

.tree {
    overflow: auto;
}

a {
    text-decoration: none;
    /* 移除链接默认的下划线 */
    color: #389538;
}

a:hover {
    text-decoration: underline;
    /* 鼠标悬浮时显示下划线 */
}

.hoverable {
    position: fixed;
    left: 80%;
}

.hoverable img {
    transition: all 0.3s ease;
    /* 添加动画效果 */
}

.hoverable img:hover {
    transform: scale(1.1);
    /* 鼠标悬停时放大图片 */
    border: 5px solid red;
    /* 添加红色边框 */
    background-color: yellow;
    /* 修改背景色为黄色 */
}

.note {
    font-family: "microsoft yahei";
    font-size: 20px;
    color: red;
}