安卓4.0下rem显示不正常的问题

在项目中使用了rem为单位，结果在Oppo和4.0下某些浏览器rem工作不正常，font-size计算出来的px总是大于预期的值，因此加了个Hack

var docEl = doc.documentElement,    resizeEvt = ‘orientationchange‘ in window ? ‘orientationchange‘ : ‘resize‘,    recalc = function() {        var clientWidth = docEl.clientWidth;        if (!clientWidth) return;        docEl.style.fontSize = 100 * (clientWidth / 320) + ‘px‘;       correctPx()    };     // 校正    function correctPx(){      var docEl = document.documentElement;      var clientWidth = docEl.clientWidth;      if (!clientWidth) return;      var div = document.createElement(‘div‘);      div.style.width = ‘1.4rem‘;      div.style.height = ‘0‘;      document.body.appendChild(div);      var ideal = 140 * clientWidth / 320;      var rmd = (div.clientWidth / ideal);      if(rmd >1.2)        docEl.style.fontSize = 100 * (clientWidth / 320)/ rmd + ‘px‘;      document.body.removeChild(div);    }// Abort if browser does not support addEventListenerif (!doc.addEventListener) return;win.addEventListener(resizeEvt, recalc, false);doc.addEventListener(‘DOMContentLoaded‘, recalc, false);