.rainbow {
	position: relative;
	padding: 2rem;
	width: 350px;
	height: 250px;
	display: flex;
	align-items: center;
	justify-content: center;
	border-radius: 10px;
	color: #454545;
	font-family: 'OpS', sans-serif;
	font-weight: 700;
	overflow: hidden;
	z-index: 0;
	
	&::before {
		content: '';
		position: absolute;
		left: -50%;
		top: -50%;
		width: 200%;
		height: 200%;
		background-repeat: no-repeat;
		background-size: 50% 50%, 50% 50%;
		background-position: 0 0, 100% 0, 100% 100%, 0 100%;
		background-image: linear-gradient(#399953, #399953), linear-gradient(#fbb300, #fbb300), linear-gradient(#d53e33, #d53e33), linear-gradient(#377af5, #377af5);
		animation: rotate 4s linear infinite;
		z-index: -2;
	}
	
	&::after {
		content: '';
		position: absolute;
		left: 6px;
		top: 6px;
		width: calc(100% - 12px);
		height: calc(100% - 12px);
		border-radius: 5px;
		background: #fff;
		z-index: -1;
	}
}

@keyframes rotate {
	100% { transform: rotate(1turn); }
}