CSS同一行div的间隔为零

<style>
  .parent { font-size: 0; }  /* 消除行内块间隙 */
  .child { 
    display: inline-block; 
    width: 100px;
    height: 100px;
    font-size: 16px; 
  }
</style>
<div class="parent">
  <div class="child" style="background-color:red;">div1</div>
  <div class="child" style="background-color:green;">div2</div>   
</div>