解决图片为适应不同机型，放大缩小时模糊失真的问题

img{

      width: 100%;

      height: 100%;

      image-rendering:-moz-crisp-edges;

      image-rendering:-o-crisp-edges;

      image-rendering:-webkit-optimize-contrast;

      image-rendering: crisp-edges;

      -ms-interpolation-mode:nearest-neighbor;

}