body {
	font-family: Helvetica, Arial, sans-serif;
	font-size: 20px;
	font-weight: bold;
}
h1 {
	width: 600px;
	text-align: center;
	margin: 15px auto;
	z-index: 10;
	font-weight: bold;
	color: #6C9BD9;
	font-size: 50px;
}
ul {list-style: none; float: left; margin: 50px 30px; line-height: 20px; font-size: 16px}
ul li.validate {color: green; font-weight: bold;  text-decoration : line-through;}
ul li.validate:before {content: '\2713 '; color: green; font-weight: bold;}
.canvas-container {float: left; margin: 50px 30px;}
#playground {display: block; width: 600px; height:600px; margin: 0 auto;}