window.onload = function(){
getRem(750,100)
};
window.onresize = function(){
getRem(750,100)
};
function getRem(pwidth,prem){
var html = document.getElementsByTagName("html")[0];
var oWidth = document.body.clientWidth || document.documentElement.clientWidth;
html.style.fontSize = oWidth/pwidth*prem + "px";
}
来源:https://www.cnblogs.com/wangshengli520/p/12652267.html