vue中rem的转换

function rems(doc: any, win: any): void {
    let docEl = doc.documentElement,
    resizeEvt = 'orientationchange' in window ? 'orientationchange' : 'resize',
    recalc = function () {
    let clientWidth = docEl.clientWidth;
    if (!clientWidth) return;
    docEl.style.fontSize = 20 * (clientWidth / 750) + 'px';
    };
    if (!doc.addEventListener) return;
    win.addEventListener(resizeEvt, recalc, false);
    doc.addEventListener('DOMContentLoaded', recalc, false);
}
export default {
    return : rems(document,window)
}