1 div{ 2         position: relative; 3     } 4     em ,span{ 5         border-style:solid dashed dashed dashed; 6         border-color:transparent; 7         border-width:3px; 8         position: absolute; 9         top:0;10         left: 0;11     }12     em{border-top-color: #3c3c3c;top:1px;}13     span{border-top-color: white;}14 15 
     
      16         
      17         
      18 
     

 效果如图:--->