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CSS

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JavaScript

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HTML 

              
                <h2>选项卡</h2>
<p>单击右上角的x按钮关闭当前选项卡：</p>

<div class="tab">
  <button
          class="tablinks"
          onclick="openCity(event, 'London')"
          id="defaultOpen"
          >
    London
  </button>
  <button class="tablinks" onclick="openCity(event, 'Paris')">Paris</button>
  <button class="tablinks" onclick="openCity(event, 'Tokyo')">Tokyo</button>
</div>

<div id="London" class="tabcontent">
  <span onclick="this.parentElement.style.display='none'" class="topright"
        >&times</span
    >
  <h3>London</h3>
  <p>London is the capital city of England.</p>
</div>

<div id="Paris" class="tabcontent">
  <span onclick="this.parentElement.style.display='none'" class="topright"
        >&times</span
    >
  <h3>Paris</h3>
  <p>Paris is the capital of France.</p>
</div>

<div id="Tokyo" class="tabcontent">
  <span onclick="this.parentElement.style.display='none'" class="topright"
        >&times</span
    >
  <h3>Tokyo</h3>
  <p>Tokyo is the capital of Japan.</p>
</div>
!

CSS 

              
                body {
  font-family: Arial;
}

/* 设置选项卡样式 */
.tab {
  overflow: hidden;
  border: 1px solid #ccc;
  background-color: #f1f1f1;
}

/* 设置选项卡内按钮的样式 */
.tab button {
  background-color: inherit;
  float: left;
  border: none;
  outline: none;
  cursor: pointer;
  padding: 14px 16px;
  transition: 0.3s;
  font-size: 17px;
}

/* 更改悬停按钮的背景色 */
.tab button:hover {
  background-color: #ddd;
}

/* 创建 active/current tablink类 */
.tab button.active {
  background-color: #ccc;
}

/* 设置选项卡内容的样式 */
.tabcontent {
  display: none;
  padding: 6px 12px;
  border: 1px solid #ccc;
  border-top: none;
}

/* 设置关闭按钮的样式 */
.topright {
  float: right;
  cursor: pointer;
  font-size: 28px;
}

.topright:hover {
  color: red;
}
!

JS 

              
                function openCity(evt, cityName) {
  var i, tabcontent, tablinks;
  tabcontent = document.getElementsByClassName("tabcontent");
  for (i = 0; i < tabcontent.length; i++) {
    tabcontent[i].style.display = "none";
  }
  tablinks = document.getElementsByClassName("tablinks");
  for (i = 0; i < tablinks.length; i++) {
    tablinks[i].className = tablinks[i].className.replace(" active", "");
  }
  document.getElementById(cityName).style.display = "block";
  evt.currentTarget.className += " active";
}

// 获取id为=“defaultOpen”的元素并单击它
document.getElementById("defaultOpen").click();
!
999px

Console