/*#a{ border:3px solid #0F9; height:100px; 100px; margin:10px; background-color:#C39; right:0px; bottom:0px; position:fixed; }*/ /*.b{ border:3px solid blue; height:100px; 100px; margin:10px; background-color:#0C3; left:50px; bottom:20px; position:absolute; } .c{ border:2px solid red; 400px; height:200px;} .d{ border:2px solid red; 400px; height:200px; position:relative;}*/ .a{ border:5px solid blue; height:100px; 100px; margin:10px; background-color:#096; position:fixed;} .aa{ border:5px solid blue; height:100px; 100px; margin:10px; left:20px; top:70px; background-color:#096; position:relative} .c{ border:3px solid #0F9; height:100px; 100px; margin:10px; background-color:#C39; right:0px; top:0px; position:fixed;} .cc{ border:3px solid #0F9; height:100px; 100px; margin:10px; background-color:#C39; left:0px; top:0px; position:fixed;} </style> </head> <body> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <div class="a">a</div><br /> <br /> <br /> <br /> <br /> <br /> <br /> <div class="aa">aa</div> <div class="c">c</div> <div class="cc">cc</div> </body> </html>
fixed 悬浮跟随浏览器边框的绝对定位
absolute 相对于浏览器边框或包含他的position 的绝对定位
relative 相对定位