function framecheck()
{
if (window.screen.availWidth < 1024 || window.screen.availHeight < 740)
 {
 document.getElementById('leftframe').style.display = 'none'
 document.getElementById('rightframe').style.display = 'none'
 document.getElementById('mainframe').style.left = 0
 document.getElementById('mainframe').style.marginLeft = 0
 }
}