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HTML 

              
                <h2>标签页眉选项卡</h2>
<p>单击选项卡菜单内的按钮:</p>
<div id="London" class="tabcontent">
  <h1>London</h1>
  <p>London is the capital city of England.</p>
</div>

<div id="Paris" class="tabcontent">
  <h1>Paris</h1>
  <p>Paris is the capital of France.</p>
</div>

<div id="Tokyo" class="tabcontent">
  <h1>Tokyo</h1>
  <p>Tokyo is the capital of Japan.</p>
</div>

<div id="Oslo" class="tabcontent">
  <h1>Oslo</h1>
  <p>Oslo is the capital of Norway.</p>
</div>

<button class="tablink" onclick="openCity('London', this, 'red')" id="defaultOpen">London</button>
<button class="tablink" onclick="openCity('Paris', this, 'green')">Paris</button>
<button class="tablink" onclick="openCity('Tokyo', this, 'blue')">Tokyo</button>
<button class="tablink" onclick="openCity('Oslo', this, 'orange')">Oslo</button>
!

CSS 

              
                /* 设置选项卡按钮的样式 */
.tablink {
  background-color: #555;
  color: white;
  float: left;
  border: none;
  outline: none;
  cursor: pointer;
  padding: 14px 16px;
  font-size: 17px;
  width: 25%;
}

/* 更改悬停按钮的背景色 */
.tablink:hover {
  background-color: #777;
}

/* 设置选项卡内容的默认样式 */
.tabcontent {
  color: white;
  display: none;
  padding: 50px;
  text-align: center;
}

/* 分别设置每个选项卡内容的样式 */
#London {background-color:red;}
#Paris {background-color:green;}
#Tokyo {background-color:blue;}
#Oslo {background-color:orange;}
!

JS 

              
                function openCity(cityName, elmnt, color) {
  // 默认情况下，使用class=“tabcontent”隐藏所有元素 */
  var i, tabcontent, tablinks;
  tabcontent = document.getElementsByClassName("tabcontent");
  for (i = 0; i < tabcontent.length; i++) {
    tabcontent[i].style.display = "none";
  }

  // 删除所有标签链接/按钮的背景色
  tablinks = document.getElementsByClassName("tablink");
  for (i = 0; i < tablinks.length; i++) {
    tablinks[i].style.backgroundColor = "";
  }

  // 显示特定选项卡内容
  document.getElementById(cityName).style.display = "block";

  // 将特定颜色添加到用于打开选项卡内容的按钮
  elmnt.style.backgroundColor = color;
}

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

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