var winW = 630, winH = 460;
 
if (parseInt(navigator.appVersion)>3) {
 if (navigator.appName=="Netscape" || navigator.appName=="Opera") {
  winW = window.innerWidth;
  winH = window.innerHeight;
 }
 if (navigator.appName.indexOf("Microsoft")!=-1) {
  winW = document.body.offsetWidth;
  winH = document.body.offsetHeight;
 }
}

if (winW<=1024)
  {document.write("<div class=\"primary\">"); }
   else
   {  if (winW==1152)
      {document.write("<div class=\"primary_1\">");}
       else
        { if (winW==1280) {document.write("<div class=\"primary_2\">");}
         else
          {if (winW==1366) {document.write("<div class=\"primary_3\">");}
            else {if (winW==1440) {document.write("<div class=\"primary_4\">");}
                   else{document.write("<div class=\"primary_o\">");}
                 }
          }
        }
    }