.matrix{
	 border-collapse: collapse;
}
.matrix td{
	border:1px solid black;
	cursor:pointer;
}

.frac input{
	height:17px;
	text-align:center;
	font-size:10px;
	border: 1px solid #CCC;
}
.frac .sz{
	border-bottom:1px solid black;
/*	padding:0px 1px 1px 1px;*/
}
.frac .n{
/*	padding:1px 1px 0px 1px;*/
}