网页如何实现适合各种显示器

function getPageSize() {
    var winW, winH;
    if(window.innerHeight) {// all except IE
        winW = window.innerWidth;
        winH = window.innerHeight;
    } else if(document.documentElement && document.documentElement.clientHeight) {// IE 6 Strict Mode
        winW = document.documentElement.clientWidth;
        winH = document.documentElement.clientHeight;
    } else if(document.body) {// other
        winW = document.body.clientWidth;
        winH = document.body.clientHeight;
    }
    return {
        WinW : winW,
        WinH : winH
    };
}