function openMainPage() {
  wwd = screen.width;       // 1024 // 1280 // screen.width
  hht = screen.height;        // 768  // 800  // screen.height
  mainPage = window.open("main.php", "main"+parseInt(Math.random()*10000), 
      "toolbar=no,menubar=no,location=no,scrollbars=no,"+
        "resizable=1,width=1024,height=768,left=0,top=0"); 
  setTimeout("mainPage.focus();", 500);
  setTimeout("mainPage.moveTo("+(screen.width/2-wwd/2)+", "+(screen.height/2-hht/2)+");", 900);
  setTimeout("mainPage.resizeTo("+wwd+","+hht+");", 1000);
} 
//