#tabla{
    width: 500px;
    height: 400px;
    background: white;
    text-align: center;
}
.btn_si{
	line-height:30px; 
	color:#fff; 
	font-family: Verdana; 
	text-decoration: none; 
	font-size: 14px;
	cursor: pointer; 
	height: 30px; 
	left: 112px; 
	position: absolute; 
	top: 247px; 
	width: 131px;
}
.btn_no{
line-height:30px; 
	color:#fff; 
	font-family: Verdana; 
	text-decoration: none;
	font-size: 14px; 
	cursor: pointer; 
	height: 30px; 
	left: 268px; 
	position: absolute; 
	top: 247px; 
	width: 131px;	
}