.portfolio_block {
	clear: both;
	width: 100%;
	display: block;
	position: relative;        
	margin-bottom: 30px;
}

.portfolio_block .foto_block { 
	width: 23%;
	float: left;
	padding: 10px;
	border: 1px solid #000;
	margin-right: 1%;
	margin-bottom: 20px;
}
.portfolio_block .foto_block img { 
	width: 100%;
	overflow: hidden;
	height: 200px;
}
.clear {
	clear: both;
	width: 100%;
	height: 1px;
}