style.css

body {
    padding: 0px;
    margin: 0px;
    background-color: #182230;
	box-sizing: border-box;

}

a {
	text-decoration: none;
	color: inherit;
	outline: none;
}

a:hover,
a:focus {
	color: #333;
}

.content.main {
	/* min-height: 0vh; */
    max-height: 0px;
	padding: 0;
    margin: 0;
}

.canvas-wrapper {
	position: relative;
	min-height: 100vh;
	overflow: hidden;
    /* padding: 20px; */
    /* border: 2px solid rgb(255, 0, 0); */

}

canvas {
    margin: 0%;
	padding: 0%;
	position: absolute;
	left: 50%;
	top: 50%;
	-webkit-transform: translate(-50%, -50%);
	transform: translate(-50%, -50%);
	width: 100%;
	height: 100vh;
    /* border: 2px solid red; */
}

.upload-btn::before,
.toggle-btn {
	padding: 10px;
	text-align: center;
	text-transform: uppercase;
	letter-spacing: 0.1em;
	color: currentColor;
	position: absolute;
	bottom: 2vmax;
	border: 1px solid;
	width: 255px;
    /* border: 2px solid red; */
}

.upload-btn::-webkit-file-upload-button {
    display: none;
}

.upload-btn::before {
	content: 'Upload your track';
	display: inline-block;
    color: white;
	left: 2vmax;
	outline: none;
	white-space: nowrap;
	-webkit-user-select: none;
	cursor: pointer;
	border-radius: 2px;
}

.upload-btn:hover::before {
	color: #FF21AB;
}

.toggle-btn {
    /* border: 2px solid gold; */
    color: white;
	background: transparent;
	/* color: currentColor; */
	right: 2vmax;
	border-radius: 2px;
	cursor: pointer;
}

.toggle-btn:focus {
	outline: none;
}

.toggle-btn:hover {
	color: #FF21AB;
}


@media screen and (max-width: 55em) {
	.toggle-btn {
		right: 10px;
		bottom: 5.5em;
		width: calc(100% - 20px);
	}
	.upload-btn::before {
		position: absolute;
		bottom: 9em;
		left: 10px;
		width: calc(100% - 40px);
	}
}