css margin 负值 合并盒子边框线
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style type="text/css">
div {
/*相对定位可以显示相邻的边框线 突出显示 某个盒子*/
position: relative;
float: left;
width: 200px;
height: 300px;
border:1px solid #ccc;
margin-left: -1px;
margin-top: -1px;
}
div:hover{
border: 1px solid #f40;
z-index: 1;
}
</style>
</head>
<body>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
</body>
</html>
