function setrem() {
var html = document.documentelement
var ww = html.clientwidth
if (ww <= 1024 && ww > 750) {
var whdef = 100 / 750
var rem = 750 * whdef
} else if (ww <= 750) {
var whdef = 100 / 750
var rem = ww * whdef
} else {
ww = math.min(ww, 1440)
var whdef = 100 / 1440
var rem = ww * whdef
}
document.documentelement.style.fontsize = rem + 'px'
}
setrem();
window.onresize = function(){
setrem()
}