CSS reset 标签初始化设置

body,h1,h2,h3,h4,h5,h6,p,dl,dd 默认有margin

ul,ol 默认有margin padding list-style

a 默认有underline

img 默认会有边框，上面会有缝隙

body,h1,h2,h3,h4,h5,h6,p,dl,dd{
    margin: 0px;
}
ul,ol{
    margin: 0px;
    padding: 0px;
    list-style: none;
}
a{
    text-decoration: none;
}
img{
    border:none;
    vertical-align: top;
}