媒体查询

css2

<link rel="stylesheet" type="text/css" media="screen" href="style.css">
media = "screen and (max-width:300px)"

媒体类型：all、screen、print、speech

css3

@media screen and (max-width:960px){
    // ......
}
@media screen and (max-device-width:960px){
    // ......
}
@media screen and (min-width:320px) and (max-width:960px){
    // ......
}

媒体类型：screen、only、not、all