#mainnav {
	float: left;
	margin-left: 400px;
	margin-top: 50px;
}

/* art */
#art img {
	margin-left: 30px;
	border: 0; 
	width:53px; 
	height: 48px; 
	background: url(../images/art.png) no-repeat;
}

#art a:hover img{
	background: url(../images/art_hg.png) no-repeat;
}

/* tech */
#tech img {
	margin-left: 30px;
	border: 0; 
	width:71px; 
	height: 48px; 
	background: url(../images/tech.png) no-repeat;
}

#tech a:hover img{
	background: url(../images/tech_hg.png) no-repeat;
}

/* tech */
#media img {
	margin-left: 30px;
	border: 0; 
	width:78px; 
	height: 48px; 
	background: url(../images/media.png) no-repeat;
}

#media a:hover img{
	background: url(../images/media_hg.png) no-repeat;
}

/* --------------------------------------- */

/* tech */
#art_btn img {
	border: 0; 
	width: 59px; 
	height: 73px; 
	background: url(../images/art_btn.png) no-repeat;
}

#art_btn a:hover img{
	background: url(../images/art_btn_chg.png) no-repeat;
}

/* tech */
#tech_btn img {
	border: 0; 
	width: 59px; 
	height: 73px; 
	background: url(../images/tech_btn.png) no-repeat;
}

#tech_btn a:hover img{
	background: url(../images/tech_btn_chg.png) no-repeat;
}

/* tech */
#media_btn img {
	border: 0; 
	width: 59px; 
	height: 73px; 
	background: url(../images/media_btn.png) no-repeat;
	
}

#media_btn a:hover img{
	background: url(../images/media_btn_chg.png) no-repeat;
}