<button class="noselect"></button>

* {
	margin: 0;
	padding: 0;
	box-sizing: border-box;
}

body {
	height: 100vh;
	overflow: hidden;
	display: flex;
	align-items: center;
	justify-content: center;
	background-color: #1b2845;
	background-image: linear-gradient(315deg, #1b2845 0%, #274060 74%);

}

.noselect {
  -webkit-touch-callout: none;
    -webkit-user-select: none;
     -khtml-user-select: none;
       -moz-user-select: none;
        -ms-user-select: none;
            user-select: none;
		-webkit-tap-highlight-color: transparent;
}

button {
	width: 150px;
	height: 50px;
	cursor: pointer;
	border: none;
	display: flex;
	align-items: center;
	justify-content: center;
	background-color: #7f5a83;
	background-image: linear-gradient(315deg, #7f5a83 0%, #0d324d 74%);
	background-size: 200% 100%;
	background-position: left;
	background-repeat: no-repeat;
	transition: 500ms;
}

button:before {
	content: 'Brighten';
	color: rgba(255,255,255,0.5);
	font-size: 16px;
	position: absolute;
	display: flex;
	align-items: center;
	justify-content: center;
	width: 140px;
	height: 40px;
	background-color: #1b2845;
	background-image: linear-gradient(315deg, #1b2845 0%, #274060 74%);
	transition: 500ms;
}

button:hover {
	background-position: right;
}

button:hover:before {
	color: rgba(255,255,255,0.8);
}

button:focus {
	outline: none;
}