html, body {
	height: 100%;
	display: flex;
	align-items: center;
	justify-content: center;
	background: linear-gradient(antiquewhite, navajowhite);
}

.sea {
	width: 300px;
	height: 300px;
	background-color: whitesmoke;
	background-image: linear-gradient(
		darkblue,
		rgba(255, 255, 255, 0) 80%,
		rgba(255, 255, 255, 0.5));
	border-radius: 5px;
	box-shadow: 0 2px 30px rgba(0, 0, 0, 0.2);
	position: relative;
	overflow: hidden;
}

.sea .title {
	color: white;
	font-size: 24px;
	font-family: serif;
	text-align: center;
	line-height: 250px;
	text-transform: uppercase;
	letter-spacing: 0.4em;
	position: absolute;
	z-index: 1;
	width: 100%;
}

.sea .wave {
	position: absolute;
	width: 500px;
	height: 500px;
	border-radius: 43%;
	top: -250px;
	left: calc((300px - 500px) / 2);
	animation: drift linear infinite;
	transform-origin: 50% 48%;
}

.sea .wave:nth-of-type(1) {
	background: deepskyblue;
	filter: opacity(0.4);
	animation-duration: 5s;
}

.sea .wave:nth-of-type(2) {
	background: deepskyblue;
	filter: opacity(0.4);
	animation-duration: 7s;
}

.sea .wave:nth-of-type(3) {
	background-color: orangered;
	filter: opacity(0.1);
	animation-duration: 9s;
}

@keyframes drift {
	from {
		transform: rotate(1turn);
	}
}