iPhone X,XS，XSMax，XR的兼容问题

设备型号	devicePixelRatio	screen.width	screen.height	图片选择@3x/2X
X/XS	3	375	812	@3x
XSMax	3	414	896	@3x
XR	2	414	896	@2x

css兼容：（用媒体查询方式）

@media only screen and (device-width: 375px) and (device-height:812px) and (-webkit-device-pixel-ratio:3) {.list-choose  .list-choose-footer{bottom: pxTorem(22)!important;}
}
@media only screen and (device-width: 414px) and (device-height:896px) and (-webkit-device-pixel-ratio:3) {.list-choose  .list-choose-footer{bottom: pxTorem(22)!important;}
}
@media only screen and (device-width: 414px) and (device-height:896px) and (-webkit-device-pixel-ratio:2) {.list-choose  .list-choose-footer{bottom: pxTorem(22)!important;}
}2.IE11浏览器的兼容问题：
IE11浏览器不支持localStorage.setItem的写法，支持localStorage.test='xxxx'的格式；
支持getItem和removerItem
![在这里插入图片描述](.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM2OTM0Nzc1,size_16,color_FFFFFF,t_70#pic_center)