var wdth=1000,sz="M",szo,iw=211,iw2=143,ih=100;
   function select_img() {
    szo=sz;
    if (document.body && document.body.offsetWidth) wdth=document.body.offsetWidth;
    else if (window.innerWidth) wdth=window.innerWidth;
    if (wdth>1200)     { sz="1";w_links=283,h_links=108,w_mitte=500,h_mitte=120,w_rechts=249,h_rechts=266; }
    else if (wdth<900) { sz="3";w_links=173,h_links=66,w_mitte=440,h_mitte=110,w_rechts=152,h_rechts=164; }
    else               { sz="3";w_links=173,h_links=66,w_mitte=440,h_mitte=110,w_rechts=152,h_rechts=164; }
   }
   function chng_img() {
    select_img() ;
    if (szo!=sz) {
     document.logo_links.width=w_links;
     document.logo_links.height=h_links;
     document.logo_links.src="images/logo_links_"+sz+".gif";
     document.logo_mitte.width=w_mitte;
     document.logo_mitte.height=h_mitte;
     document.logo_mitte.src="images/logo_mitte_"+sz+".gif";
     document.logo_rechts.width=w_rechts;
     document.logo_rechts.height=h_rechts;
     document.logo_rechts.src="images/logo_rechts_"+sz+".gif";
    }
   }
   function init() {
    window.onresize = chng_img;
   }