extension.css

.updateContent {
	top: 20%;
	left: 20%;
	width: 60%;
	height: 60%;
	background-color: rgba(0, 0, 0, 0.6);
	z-index: 100;
	overflow-y: scroll;
}

.updateContentClose {
	position: absolute;
	right: 0px;
	width: 50px;
	height: 50px;
	background: silver;
	border-radius: 25px;
	box-shadow: 2px 2px 5px 0px black;
	cursor: pointer;
	z-index: 100;
}

.updateContentClose:hover {
	background: red;
}

.updateContentClose:before {
	position: absolute;
	content: '';
	width: 30px;
	height: 10px;
	background: white;
	transform: rotate(45deg);
	top: 20px;
	left: 10px;
}

.updateContentClose:after {
	content: '';
	position: absolute;
	width: 30px;
	height: 10px;
	background: white;
	transform: rotate(-45deg);
	top: 20px;
	left: 10px;
}

.updateContentButton {
	z-index: 100;
	position: absolute;
	bottom: 15px;
	width: 30%;
	left: 35%;
}