媒体查询rem如何换算

Question

@media only screen and (max-width: 310px) and (min-width: 300px) {html {font-size: 9px}}
@media only screen and (max-width: 320px) and (min-width: 310px) {html {font-size: 9px} }
@media only screen and (max-width: 360px) and (min-width: 320px) {html {font-size: 9px}.filter-menu-list ul li i{margin-top:-.1rem;} .filter-menu-list ul li em{margin-top:-.4rem;}}
@media only screen and (max-width: 360px) and (min-width: 350px) {html {font-size: 10px} }
@media only screen and (max-width: 480px) and (min-width: 360px) {html {font-size: 10px}.filter-menu-list ul li i{margin-top:-.1rem;} .filter-menu-list ul li em{margin-top:0rem;}}
@media only screen and (max-width: 480px) and (min-width: 470px) {html {font-size: 13.33333px}}
@media only screen and (max-width: 560px) and (min-width: 480px) {html {font-size: 13.33333px}}
@media only screen and (max-width: 570px) and (min-width: 560px) {html {font-size: 15.83333px}}
@media only screen and (max-width: 640px) and (min-width: 570px) {html {font-size: 15.83333px}}
@media only screen and (max-width: 640px) and (min-width: 630px) {html {font-size: 17.77778px}}
@media only screen and (max-width: 710px) and (min-width: 640px) {html {font-size: 17.77778px} }

上面那段媒体查询是之前项目里使用的，所以现在只能继续用这种方法适配，设计图是750px的，假设有一个宽度为600px的元素，如何换算成rem呢，嗯~~, 600/10px或者600/xxx什么的，好像和设计图看起来都不太对。

Answer 1

在设计图上宽度为600px的元素要先除以2，也就是600/2/10。750px的设计图是iPhone6/7，dpr为2，要除以2。

Answer 2

你这个多媒体查询里没有覆盖到你分辨率为750px的大小