.tete{
	text-align: center;
	font-size: 20px;
}

.item{
	background-color: rgba(66, 122, 119, 0.6); 
	border-radius: 20px;
	margin-right: 15px;
	margin-bottom: 10px;
	text-align: center;
	padding-bottom: 5px;
	padding-top: 3px;
	cursor: pointer;
	text-align: center;
	vertical-align: center;
}

table.exercice, table.exercice th, table.exercice td, table.exercice tr{
	border: solid black 2px;
} 

#button{
	margin-bottom: 20px;
}

#alert1{
	visibility: hidden;
}