手机端js配置rem

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var a=document.querySelector(“meta[name=viewport]”);
var b=“orientationchange” in window?“orientationchange”:“resize”;
var d=function(){var f=document.body||document.documentElement;
var e=f.clientWidth;return e/75};
var c=function(){document.getElementsByTagName(“html”)[0].setAttribute(“style”,“font-size:”+d()+“px !important”)};
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