使用bootstrap书写轮播图效果

1、案例分析

     Bootstrap已经提供了轮播图的完整案列，参考文档：https://v3.bootcss.com/javascript/#carousel

2、实例

<div id="carousel-example-generic" class="carousel slide" data-ride="carousel">
  <!-- Indicators -->
  <ol class="carousel-indicators">
    <li data-target="#carousel-example-generic" data-slide-to="0" class="active"></li>
    <li data-target="#carousel-example-generic" data-slide-to="1"></li>
    <li data-target="#carousel-example-generic" data-slide-to="2"></li>
  </ol>

  <!-- Wrapper for slides -->
  <div class="carousel-inner" role="listbox">
    <div class="item active">
      <img src="..." alt="...">
      <div class="carousel-caption">
        ...
      </div>
    </div>
    <div class="item">
      <img src="..." alt="...">
      <div