(function (doc, win) { var docEl = doc.documentElement, resizeEvt = "orientationchange" in window ? "orientationchange" : "resize", recalc = function () { var clientWidth = docEl.clientWidth; //var foot = document.getElementById("foot"); if (!clientWidth) return; if (clientWidth<750){ docEl.style.fontSize = 100 * (clientWidth / 750) + "px"; console.log(100 * (clientWidth / 750) + "px"); }else{ docEl.style.fontSize = "100px"; } }; if (!doc.addEventListener) return; win.addEventListener(resizeEvt, recalc, false); doc.addEventListener('DOMContentLoaded', recalc, false); })(document, window);