* {

	margin: 0;
	padding: 0;
	box-sizing: border-box;
	font-family: sans-serif;

}

.app {

	display: flex;
	justify-content: center;
	align-items: center;
	height: 100vh;

}

.calculator {

	background-color: rgb(22, 22, 22);
	width: 100%;
	max-width: 375px;
	min-height: 640px;
	display: flex;
	flex-direction: column;
	border-radius: 1.5rem;
	overflow: hidden;

}

.display {

	min-height: 200px;
	padding: 1.5rem;
	display: flex;
	justify-content: flex-end;
	align-items: flex-end;
	color: rgb(255, 255, 255);
	text-align: right;
	flex: 1 1 0%;

}

.display .content {

	display: flex;
	flex-direction: column;
	justify-content: flex-end;
	width: 100%;
	max-width: 100%;
	overflow: auto;

}

.display .input {
	width: 100%;
	font-size: 1.25rem;
	margin-bottom: 0.5rem;
}

.display .output {

	font-size: 3rem;
	font-weight: 700;
	width: 100%;
	white-space: nowrap;

}

.display .operator {

	color: rgb(255, 21, 0);

}

.display .brackets,
.display .percent {

	color: rgb(140, 134, 255);

}

.keys {

	background-color: black;
	padding: 1.5rem;
	border-radius: 1.5rem 1.5rem 0 0;
	display: grid;
	grid-template-columns: repeat(4, 1fr);
	grid-template-rows: repeat(5, 1fr);
	grid-gap: 1rem;
	box-shadow: 0px -2px 16px rgba(0, 0, 0, 0.2);

}

.keys .key {

	position: relative;
	cursor: pointer;

	display: block;
	height: 0;
	padding-top: 100%;
	background-color: rgb(35, 35, 35);
	border-radius: 1rem;
	transition: 0.2s;
	user-select: none;

}

.keys .key span {

	position: absolute;
	top: 50%;
	left: 50%;
	transform: translate(-50%, -50%);

	font-size: 2rem;
	font-weight: 700;
	color: white;

}

.keys .key:hover {

	box-shadow: inset 0px 0px 8px rgba(0, 0, 0, 0.2);

}

.keys .key.operator span {

	color: rgb(255, 21, 0);

}

.keys .key.action span {

	color: rgb(140, 134, 255);
    
}