styles.css

* {
	box-sizing: border-box;
  -webkit-touch-callout: none; /* iOS Safari */
    -webkit-user-select: none; /* Safari */
     -khtml-user-select: none; /* Konqueror HTML */
       -moz-user-select: none; /* Old versions of Firefox */
        -ms-user-select: none; /* Internet Explorer/Edge */
            user-select: none; /* Non-prefixed version, currently
                                  supported by Chrome, Opera and Firefox */                                  
}

body {
	background-color: #240b36;
    height: 700px;
    overflow: hidden;
}

#calculator-container {
	font-family: arial;
	font-size: 0px;
	width: 454px;
	position: relative;
	margin-top: 150px;
	left: 50%;
	margin-left: -227px;
}

#calculator-container::before {
	content: "";
	position: absolute;
	top: -600px;
	left: -600px;
	right: -600px;
	bottom: -600px;
	background: radial-gradient(rgb(65,87,232) -10%, rgb(0,0,0,0) 70%);
	z-index: -1;
}

#display {
	height: 50px;
	width: 430px;
	margin: 0px 5px 5px 5px;
	padding: 0px 18px 0px 18px;
	border-radius: 0px 0px 5px 5px;
	font-size: 28px;
	line-height: 50px;
	text-align: right;
	color: white;
	background-color: rgb(25,19,38,0.17);
	overflow: hidden;
	text-overflow: ellipsis;
}

#history {
	height: 31px;
	width: 430px;
	margin: 0px 5px 0px 5px;
	padding: 0px 18px 0px 18px;
	border-radius: 5px 5px 0px 0px;
	font-size: 16px;
	line-height: 50px;
	text-align: right;
	color: rgb(255,255,255,0.4);
	background-color: rgb(25,19,38,0.17);	
	overflow: hidden;
	text-overflow: ellipsis;
}

.button {
	display: inline-block;
	height: 50px;
	width: 100px;
	margin: 5px;
	border-radius: 5px;
	font-size: 20px;
	line-height: 50px;
	text-align: center;
	color: white;
	background-color: rgb(25,19,38,0.17);
	cursor: pointer;
}

#ac-button {
	background-color: rgb(255,255,255,0.9);
	color: black;
	mix-blend-mode: overlay;
}

#multiply-button, #divide-button, #minus-button, #plus-button {
	background-color: rgb(125, 47, 117);
	color: black;
	opacity: 0.6;
}

#equals-button {
	background-color: #4364f7;
}



@media (min-width: 600px) {
	.button:hover {
		mix-blend-mode: screen;
		background-color: rgb(255,255,255, 0.1);
	}

	#ac-button:hover {
		filter: invert(1);
		mix-blend-mode: screen;
	}

	#equals-button:hover {
		filter: none;
		mix-blend-mode: overlay;
	}

	#multiply-button:hover, #divide-button:hover, #minus-button:hover, #plus-button:hover {
		filter: invert(1);
		mix-blend-mode: overlay;
		opacity: 1;
	}

	.button:active {
		transform: translateY(1px);
	}
}



@media (max-width: 600px) {
	* {
		-webkit-tap-highlight-color: transparent;
	}

	body {
		padding: 0px;
		margin: 0px;
		top: 0px;
		overflow: hidden;
	}

	#calculator-container {
		position: fixed;
		top: 0px;
		left: 0px;
		bottom: 0px;
		right: 0px;
		width: 100%;
		padding: 0%;
		margin: 0px;
		display: flex;
		justify-content: space-between;
		align-content: space-around;
		flex-wrap: wrap;
		border-radius: 0px;
		background-image: linear-gradient(rgb(69,87,232) 10%, rgb(195,20,50,0) 120%);
	}

	#calculator-container::before {
		background: none;
	}

	#display-container {
		display: inline-block;
		width: 100%;
		height: 100vw;
		background: linear-gradient(rgb(255,255,255,0.2) 0%, rgb(0,0,0,0));
	}

	#blank-space {
		height: 50vw;
	}

	#display {
		height: 25vw;
		width: 100%;
		padding: 0px 19px 0px 19px;
		margin: 0% 0% 0% 0%;
		font-size: 13vw;
		line-height: 25vw;
		background-color: rgb(0,0,0,0);
	}

	#history {
		height: 25vw;
		width: 100%;
		padding: 0px 19px 0px 19px;
		margin: 0% 0% 0% 0%;
		font-size: 28px;
		line-height: 40vw;
		background-color: rgb(0,0,0,0);
	}

	.row {
		width: 100%;
		padding: 0%;
		display: flex;
		justify-content: space-evenly;
	}

	#calculator {
		position: absolute;
		height: 225vw;
		width: 100%;
		bottom: 0px;
		display: flex;
		flex-wrap: wrap;		
	}

	.button {
		position: relative;
		height: 25vw;
		width: 25vw;
		margin: 0%;
		padding: 0%;
		font-size: 8vw;
		line-height: 25vw;
		border-radius: 0%;
		background-image: linear-gradient(rgb(0,0,0,0.1), rgb(0,0,0,0) 100%);
		background-color: rgb(0,0,0,0);
	}

	.final-column {
		margin: 0% 0% 0% 0%;
	}

	.button:active {
		mix-blend-mode: screen;
		background-color: rgb(255,255,255, 0.1);
	}

	#ac-button:active {
		filter: invert(1);
		mix-blend-mode: screen;
	}

	#equals-button:active {
		filter: none;
		mix-blend-mode: overlay;
	}

	#multiply-button:active, #divide-button:active, #minus-button:active, #plus-button:active {
		filter: invert(1);
		mix-blend-mode: overlay;
		opacity: 1;
	}
}