我们先看一些官方提供的

使用link的话，可以用media属性做条件判断

在css中的话，可以@media screen用来做判断

也可以拿区间值做判断，如图所示400px - 700px

我也把我平时用的分享给大家，随便复制别跟我客气

@media screen and (orientation: portrait) {/*竖屏 css*/
} 
@media screen and (orientation: landscape) {/*横屏 css*/
}
@media screen and (min-width:1366px){/*pc端 css*/
}/*iphone 5/5s/5se */
@media screen and (max-width:569px){top: 7%;left: 18%;
}
/*iphone 6/7/8 */
@media screen and (min-width:569px) and (max-width:668px){top: 12%;left: 20%;
}
/*iphone 6p/7p/8p */
@media screen and (min-width:668px) and (max-width:737px){top: 14%;left: 20%;
}
/*iphone x */
@media screen and (min-width:737px) and (max-width:813px){top: 12%;left: 21%;
}
/*ipad*/
@media screen and (min-width:813px) and (max-width:1025px){top: 22%;left: 21%;
}
/*ipad pro*/
@media screen and (min-width:1024px){top: 25%;left: 21%;
}