Native JS는 Tab 탭의 다양한 효과를 구현합니다.

<p id="notice" class="notice">
  <p id="notice-title" class="notice-title">
    <ul>
      <li class="select"><a href="#">公告</a></li>
      <li><a href="#">规则</a></li>
      <li><a href="#">论坛</a></li>
      <li><a href="#">安全</a></li>
      <li><a href="#">公益</a></li>
    </ul>
  </p>
  <p id="notice-content" class="notice-content">
    <p class="mod" style="display: block">
      <ul>
        <li>
          <a href="#">张勇：要玩快乐足球</a>
        </li>
        <li>
          <a href="#">阿里2000万驰援灾区</a>
        </li>
        <li>
          <a href="#">旅游宝让你边玩边赚钱</a>
        </li>
        <li>
          <a href="#">多行跟进阿里信用贷款</a>
        </li>
      </ul>
    </p>
    <p class="mod" style="display: none">
      <ul>
        <li>
          <span>
            [
            <a href="">通知</a>
            ]
          </span>
          <a href="#">“滥发”即将换新</a>
        </li>
        <li>
          <span>
            [
            <a href="">通知</a>
            ]
          </span>
          <a href="#">比特币严管啦</a>
        </li>
        <li>
          <span>
            [
            <a href="">通知</a>
            ]
          </span>
          <a href="#">禁发商品名录</a>
        </li>
        <li>
          <span>
            [
            <a href="">通知</a>
            ]
          </span>
          <a href="#">商品熟悉限制</a>
        </li>
      </ul>
    </p>
    <p class="mod" style="display: none">
      <ul>
        <li>
          <span>
            [
            <a href="">聚焦</a>
            ]
          </span>
          <a href="#">金牌卖家再启航</a>
        </li>
        <li>
          <span>
            [
            <a href="">功能</a>
            ]
          </span>
          <a href="#">橱窗规则升级啦</a>
        </li>
        <li>
          <span>
            [
            <a href="">话题</a>
            ]
          </span>
          <a href="#">又爱又恨优惠券</a>
        </li>
        <li>
          <span>
            [
            <a href="">工具</a>
            ]
          </span>
          <a href="#">购后送店铺红包</a>
        </li>
      </ul>
    </p>
    <p class="mod" style="display: none">
      <ul>
        <li>
          <span>
            [
            <a href="">要闻</a>
            ]
          </span>
          <a href="#">年轻干部要摒弃盲目求快的人生哲学</a>
        </li>
        <li>
          <span>
            [
            <a href="">近来好</a>
            ]
          </span>
          <a href="#">都说实体店不行了，可便利店为啥越开越多？</a>
        </li>
        <li>
          <span>
            [
            <a href="">冬奥会</a>
            ]
          </span>
          <a href="#">永远有杯咖啡留给您</a>
        </li>
        <li>
          <span>
            [
            <a href="">总书记</a>
            ]
          </span>
          <a href="#">从高空视角看习总书记的春节足迹    奋进新时代</a>
        </li>
      </ul>
    </p>
    <p class="mod" style="display: none">
      <ul>
        <li>
          <a href="#">走近无声课堂</a>
        </li>
        <li>
          <a href="#">淘宝之行大众评审赢公益</a>
        </li>
        <li>
          <a href="#">爱心品牌联合征集</a>
        </li>
        <li>
          <a href="#">名公益机构淘宝开店攻略</a>
        </li>
      </ul>
    </p>
  </p>
</p>

*{
    margin: 0;
    padding: 0;
    list-style: none;
    font-size: 12px;
    box-sizing: border-box;
}
.notice{
    width: 302px;
    height: 100px;
    margin: 10px;
    border: 1px solid #eee;
    overflow: hidden;
}
.notice-title{
    height: 26px;
    background: #f7f7f7;
}

.notice-title li{
    float: left;
    width: 60px;
    line-height: 26px;
    text-align: center;
    overflow: hidden;
    background: #fff;
    border-bottom: 1px solid #eee;
    background: #f7f7f7;
}

.notice li a:link,
.notice li a:visited{
    text-decoration: none;
    color: #000;
}

.notice li a:hover{
    color: #f90;
}
.notice-title li.select{
    background: #fff;
    border-bottom-color: #fff;
    border-left: 1px solid #eee;
    border-right: 1px solid #eee;
    font-weight: bold;
}
.notice-title li:first-child.select{
    border-left: none;
}
.notice-title li:last-child.select{
    border-right: none;
}

.notice-content .mod{
    padding: 12px 5px;
}
.notice-content .mod ul{
    width: 300px;
    font-size: 0;
}
.notice-content .mod ul li{
    display: inline-block;
    width: 145px;
    height: 25px;
    line-height: 25px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

function $(id) {
    return typeof id==='string'? document.getElementById(id):id;
}

//获取鼠标滑过或点击的标签和要切换内容的元素
var titles = $('notice-title').getElementsByTagName('li'),
    ps = $('notice-content').getElementsByTagName('p');
if(titles.length != ps.length){
  return;
}
// 遍历titles下的所有li
for(var i = 0; i < titles.length; i++) {
  // 添加索引
  titles[i].id = i;
  titles[i].onmouseover = function () {
    //清除所有title上的class，将所有的p设置为隐藏
    for(var j=0; j<titles.length; j++) {
      titles[j].className = &#39;&#39;;
      ps[j].style.display = &#39;none&#39;;
    }
    //设置当前li为高亮显示
    this.className = &#39;select&#39;;
    ps[this.id].style.display = &#39;block&#39;;
  }
}

var timer = null;

var list = $('notice-title').getElementsByTagName('li'),
    ps = $('notice-content').getElementsByTagName('p');
if(list.length != ps.length){
  return;
}
for(var i = 0; i < list.length; i++) {
  list[i].id = i;
  list[i].onmouseover = function () {
    var self = this;
    //如果存在准备执行的定时器，立刻清除，只有当前停留时间大于500ms时才开始执行
    if(timer) {
      clearTimeout(timer);
      timer = null;
    }
    //延迟半秒执行
    timer = setTimeout(function () {
      for(var j = 0; j < list.length; j++) {
        list[j].className = &#39;&#39;;
        ps[j].style.display = &#39;none&#39;;
      }
      list[self.id].className = &#39;select&#39;;
      ps[self.id].style.display = &#39;block&#39;;
    }, 500)
  }
}