本文讲的等宽布局是在不手动设置元素宽度的情况下，使用纯css实现各个元素宽度都相当的效果。
1、使用table-cell实现(兼容ie8)
<style>
body,div{
margin: 0;
padding: 0;
}
.table-layout{
display: table;/*父元素必须设置为table*/
table-layout: fixed;/*这个属性一定要有，否则达不到效果*/
width: 50%;
margin: 20px auto;
}
.table-cell-layout{
display: table-cell;/*子元素必须设置为table-cell*/
height: 40px;
border: 1px solid #666;
border-left: none;
}
.table-cell-layout:first-child{
border-left: 1px solid #666;
}
</style>
<body>
<ul class="table-layout">
<li class="table-cell-layout">li1</li>
<li class="table-cell-layout">li2</li>
<li class="table-cell-layout">li3</li>
<li class="table-cell-layout">li4</li>
<li class="table-cell-layout">li5</li>
</ul>
</body>
2、使用flex布局来实现
<style>
body,div{
margin: 0;
padding: 0;
}
.flex-layout{
display: flex;
width: 50%;
margin: 20px auto;
}
.flex-item{
flex: 1;
height: 40px;
border: 1px solid #666;
border-left: none;
}
.flex-item:first-child{
border-left: 1px solid #666;
}
</style>
<body>
<ul class="flex-layout">
<li class="flex-item">li1</li>
<li class="flex-item">li2</li>
<li class="flex-item">li3</li>
<li class="flex-item">li4</li>
<li class="flex-item">li5</li>
</ul>
</body>
来源：https://segmentfault.com/a/1190000017764682