1、边界
margin表外间距
<body> <div style="100px; height:100px; background-color:#F00; margin:10px"> </div> <div style="100px; height:100px; background-color:#F00;margin:10px"> </div> </body>
padding内容与单元格之间的间距（当用padding时，宽高要减去设置的padding值；不然表格就是比原来的大，大出的数值就是设置的padding值）
<body> <div style="50px; height:50px; background-color:#F00; padding:25px 25px 25px 25px "> <div style="50px; height:50px; background-color:#00F"></div> </div> </body>
用div布置网页是首先要给网页的margin和padding清零并居中（写在head里面）auto是居中
<head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>无标题文档</title> <style type="text/css"> *{ margin:0 auto; padding:o} </style> </head> <body> <div style="100px; height:75px; background-color:#F00; padding-top:25px "> <div style="50px; height:50px; background-color:#00F;"></div> </div> </body>
margin：10px 5px 10px 5px ； padding：10px 5px 10px 5px 意思是上右下左（顺时针）为10、5、10、5
2、边框border，属性有border-width border-style border-color border-top /bottom /left /right
<head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>无标题文档</title> <style type="text/css"> *{ margin:0 auto; padding:o} </style> </head> <body> <div style="100px; height:75px; background-color:#F00; padding-top:25px; border-5px; border-color:#0F0; border-style:solid "> <div style="50px; height:50px; background-color:#00F;"></div> </div> </body>
bord：像素 边框样式 颜色
<head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>无标题文档</title> <style type="text/css"> *{ margin:0 auto; padding:o} </style> </head> <body> <div style="100px; height:75px; background-color:#F00; padding-top:25px; border:10px outset #000"> <div style="50px; height:50px; background-color:#00F;"></div> </div> </body>
当有边框的时候，设置margin值要减掉边框的宽
<head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>无标题文档</title> <style type="text/css"> *{ margin:0 auto; padding:o} </style> </head> <body> <div style="200px; height:200px; background-color:#F00;border:10px outset #000; margin-top:50px"> <div style="100px; height:100px; background-color:#00F; margin:30px; border:20px solid #000000"></div> </div> </body>
当div中宽高都是0边框不等于0时
<head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>无标题文档</title> <style type="text/css"> *{ margin:0 auto; padding:o} </style> </head> <body> <div style="0px; height:0px;margin-top:100px; border-bottom:100px solid #0F0; border-top:100px solid #F00; border-left:100px solid #00C; border-right:100px solid #FF0"> </div> </body>
