style.css

* {
	margin: 0; padding: 0;
}

html, body {
	width: 100%;
}

.credits {
	border: 1px solid black;
	width: 260px;
	box-shadow: 2px 2px grey;
	margin: 5% auto 0 auto;
}

#container {
	width: 500px; height: 500px;
	border: 1px solid black;
	display: table;
	border-spacing: 10px;
	border-collapse: separate;
	background-color: #99ccea;
	position: fixed;
	margin-left:-250px; margin-top:-250px;
    top: 50%; left: 50%;
    table-layout: fixed;
}

#trdisplay {
	display: table-row;
	text-align: right;
}

#tcdisplay {
	display: table-cell;
	border: 5px solid #8eb1c8;
	text-align: center;
	background-color: white;
	height: 100px;
	font-family: helvetica;
}

.trow {
	display: table-row;
}

.tcbutton {
	display: table-cell;
	border: 5px solid #8eb1c8;
	text-align: center;
	background-color: white;
	font-family: helvetica;
	font-size: 20px;
}

.tcbutton:active:hover {
	background-color: grey;
}