<meta id="viewport" name="viewport" content="width=device-width; initial-scale=1.0; maximum-scale=1.0">

<script type="text/javascript" language="javascript">
function Dimension (Width,Height)
{
var Width = (window.screen.width)  
var Height = (window.screen.height)        
   
if(Width >= 800 && Width < 1024) and (Height >= 600 && Height < 768)
         document.location.href = main1.html';     
else     
if(Width >= 1024 && Width < 1280) and (Height >= 768 && Height < 800)
   
         document.location.href = 'main2.html';     
else     
if(Width >= 1280) and (Height >= 800 && Height < 1024)
         document.location.href = 'main3.html;     
else     
   
         document.location.href = 'main.html';     
};
</script>

var IE = (document.all);
   var NC = (document.layers);
   var Opera = (document.getElementById);
function  getHeight()
{ if (IE) return document.body.clientHeight;
   if (NC) return window.innerHeight;
   if (Opera) return document.body.offsetHeight;
   return 600;
}
function  getWidth()
{ if (IE) return document.body.clientWidth;
   if (NC) return window.innerWidth;
   if (Opera) return document.body.offsetWidth;
   return 800;
}