@media screen and (min-width: 0px) and (max-width: 240px) 
{
    div#contents { 
     width: 40%;
 }
   div#sidebar { display:none; }
   div#head { display:none; }
}
@media screen and (min-width: 241px) and (max-width: 320px) 
{
    div#contents { 
     width: 45%;
 }
   div#sidebar { display:none; }
   div#head { display:none; }
}
@media screen and (min-width: 321px) and (max-width: 480px) 
{
   div#contents { 
    width: 53%; 
 }
   div#sidebar { display:none; }
   div#head { display:none; }
}
@media screen and (min-width: 481px) and (max-width: 819px)
 {
    div#head { width: 80%; }
    div#contents { width: 80%; }
   div#sidebar { display:none; }
}

@media screen and (min-width: 820px) 
{ 
    div#head { width: 100%; }
    div#contents { width: 100%; }
   div#sidebar { width: 100%; }
}

img{
	max-width: 100%;
	height: auto;
	display:block;
}