function getScreenWidth() {
    isNetscape = (navigator.appName == "Netscape");
    available = (isNetscape) ? window.innerWidth : document.body.clientWidth;
    return available;
  }
  
  function centerPage() {
    w = getScreenWidth();
    lef = Math.round(w - 998) / 2;
    document.getElementById('content').style.left = lef;
    foo  = document.getElementById('footer');
    kad = document.getElementById('kader_midden');
    con = document.getElementById('page_content');
    sha = document.getElementById('shape');
    hi = con.offsetHeight;
    //alert(hi);
    if (hi < 440) hi = 440;
    foo.style.top = (hi + 200) + 'px';
    kad.style.height = hi + 181 + 'px';
    sha.style.top = (hi - 194) + 'px';
    
  }