1 function rems(doc: any, win: any): void {

 2     let docEl = doc.documentElement,

 3     resizeEvt = 'orientationchange' in window ? 'orientationchange' : 'resize',

 4     recalc = function () {

 5     let clientWidth = docEl.clientWidth;

 6     if (!clientWidth) return;

 7     docEl.style.fontSize = 20 * (clientWidth / 750) + 'px';

 8     };

 9     if (!doc.addEventListener) return;

10     win.addEventListener(resizeEvt, recalc, false);

11     doc.addEventListener('DOMContentLoaded', recalc, false);

12 }

13 export default {

14     return : rems(document,window)

15 }