1 <!DOCTYPE html> 2 <html> 3 <head> 4 <meta charset="UTF-8"> 5 <title></title> 6 <style type="text/css"> 7 /*层叠选择器*/ 8 .ka{ 9 width: 500px; 10 height: 500px; 11 border: 2px solid gray; 12 background-color: green; 13 } 14 .ka #kb{ 15 width: 200px; 16 height: 200px; 17 border: 2px solid gray; 18 background-color: greenyellow; 19 } 20 .ka #kc{ 21 width: 300px; 22 height: 300px; 23 border: 2px solid gray; 24 background-color: orange; 25 } 26 </style> 27 </head> 28 <body> 29 <div class="ka"> 30 <div id="kb"></div> 31 <div id="kc"> 32 <div id="kb"></div> 33 </div> 34 </div> 35 36 </body> 37 </html>