rem iphone6/7/8 375设计稿

    (function (doc, win) {
    var docEl = win.document.documentElement;
    var resizeEvt = 'orientationchange' in window ? 'orientationchange' : 'resize';
    
    var refreshRem = function () {
        var clientWidth = win.innerWidth
                        || doc.documentElement.clientWidth
                        || doc.body.clientWidth;

        console.log(clientWidth)
        if (!clientWidth) return;
        var fz;
        var width = clientWidth;
        fz = 16 * width / 375;
        docEl.style.fontSize = fz + 'px';//这样每一份也是16px,即1rem=16px
    };

    if (!doc.addEventListener) return;
    win.addEventListener(resizeEvt, refreshRem, false);
    doc.addEventListener('DOMContentLoaded', refreshRem, false);
    refreshRem();

    })(document, window);