* {
	margin: 0;
	padding: 0;
}
html, body {
	height: 100%;
	overflow: hidden;
}
#container {
	margin: 0 auto;
	text-align: center;
	width: 100%;
	height: 100%;
}
#bt {
	display: none;
	width: 100px;
	height: auto;
	position: absolute;
	background: #2365a7;
	font: 1.5em Arial;
	font-color: #ceceec;
	border-radius: 15px;
}
#bt:hover {
	background: #3c4e61;
}