body
{
	margin: 0px;	
	background:white;
	vertical-align:top;
}
@media all and (min-width:300px) and (max-width:450px) 
{
	body
	{
		background: white;
		vertical-align:top;
		/* visibility:hidden; ko dung, an phan body*/
	}
	.desktop
		{
			display:none;	
		}
	.tablet
		{
			display:none;	
		}
	.mobile
		{
			display:block;	
		}
}