/* 兼容iphone4/4s */
@media (device-height:480px) and (-webkit-min-device-pixel-ratio:2){}
/* 兼容iphone5 */
@media (device-height:568px) and (-webkit-min-device-pixel-ratio:2){}
@media 适配兼容
原文：http://www.cnblogs.com/dtdxrk/p/4571258.html
