html,
body {
	height: 100%;
	margin: 0;
}

body {
	font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
	cursor: pointer;
}

* {
	-webkit-touch-callout: none;
	/*系统默认菜单被禁用*/
	-webkit-user-select: none;
	/*webkit浏览器*/
	-khtml-user-select: none;
	/*早期浏览器*/
	-moz-user-select: none;
	/*火狐*/
	-ms-user-select: none;
	/*IE10*/
	user-select: none;
}

* {
	-webkit-tap-highlight-color: rgba(0, 0, 0, 0);
	-webkit-tap-highlight-color: transparent;
	/* For some Androids */
}

.container {
	display: flex;
	justify-content: center;
	align-items: center;
	height: 100%;
}

#score {
	position: absolute;
	top: 30px;
	right: 30px;
	font-size: 2em;
	font-weight: 900;
}

#introduction {
	width: 200px;
	height: 150px;
	position: absolute;
	font-weight: 600;
	font-size: 0.8em;
	font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
	text-align: center;
	transition: opacity 2s;
}

#restart {
	width: 120px;
	height: 120px;
	position: absolute;
	border-radius: 50%;
	color: white;
	background-color: red;
	border: none;
	font-weight: 700;
	font-size: 1.2em;
	font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
	display: none;
	cursor: pointer;
}

#perfect {
	position: absolute;
	opacity: 0;
	transition: opacity 2s;
}