使用CSS3媒体查询控制响应式图片

HTML

<div class="changeImg"></div>
    					

CSS

/*当屏幕宽度大于641像素时*/
@media screen and (min-width: 641px) {
    .changeImg {
        background-image: url(big.jpg);
        background-repeat: no-repeat;
        height: 440px;
    }
    }
    
    /*当屏幕宽度小于641像素时*/
    @media screen and (max-width: 640px) {
    .changeImg {
        background-image: url(small.png);
        background-repeat: no-repeat;
        height: 440px;
    }
}