style.css

body
{
	position: relative;
	margin:0;
	padding:0;
	font-family:arial;
	background-color:#222222;
	color:#FFD700;
	height: 100vh;
	display: flex;
	flex-direction: column;
	justify-content: center;
	align-items: center;
}
.header{
	text-align: center;
	margin-bottom: 1rem;
	padding: 1rem 0;
}
.container{
	margin-bottom: 1rem;
}
.insideCard
{
	height:310px;
	padding:5px;
	border-radius:15px;
	box-shadow:0px 0px 25px #000;
}
table
{
	border-collapse: collapse;
}
td
{
	height:100px;
	width:100px;
	text-align:center;
	font-size:80px;
	line-height:80px;
	
}
.border-right
{
	border-right:2px solid #FFD700;
}
.border-bottom
{
	border-bottom:2px solid #FFD700;
}
td:hover
{
	cursor:pointer;
	background:rgba(0,0,0,0.4);
}
.card
{
	width:313px;
}
#result
{
	text-align:center;
	font-weight:bold;
	font-size:30px;
	color:FFD700;
}
#resetBtn
{
	width:100%;
	height:35px;
	font-size:18px;
	background:#333333;
	color:#FFD700;
	border-radius:5px;
	border:1px solid #FFD700;
	outline:none;
	box-shadow:0px 0px 15px #000 inset, 0px 0px 0px 2px #222 inset;
	display:none;
}
#resetBtn:hover
{
	cursor:pointer;
	background-color:#1e1e1e;
}
#resetBtn:active
{
	background-color:#3e3e3e;
}
footer{
	width: 100vw;
	display: flex;
	align-items: center;
	justify-content: center;
	background-color: #333;
	padding: 1rem 0;
	position: absolute;
	bottom: 0;

}
footer a{
	text-decoration: none;
	color: #fff;
}
footer a:hover{
	color: inherit;
	text-shadow: 0px 2px 2px #8f7a00;
}