.nb-button {
	margin-bottom: 30px;
	text-align: center; 
	border: 2px solid rgb(200,200,200); 
	border-radius: 10px; 
	font-size: 12em; 
	line-height: 1em; 
	color:white; 
	font-family: digital7;
}

.nb-button.ok {
	color: green;
}

.nb-button.nok {
	color: red;
}