.done {
	color: gray;
	text-decoration: line-through;
}

.hidden {
	display: none;
}

* { 
	margin:0;  
	padding:0;  
}
body {
	font-family:"Microsoft Yahei", sans-serif;
	font-size:100%;
	background:#555;
	height: 100%;
	width: 100%;
	position: fixed;
	top: 0;
	left: 0;
	z-index: -999;
}

header {
	z-index: 1001;
	position: absolute;
	left: 5%;
	transform: translate(-25px, -50%);
	top: 8%;
	width: 50px;
	height: 50px;
	overflow:hidden;
	border-radius: 25px;
	transition: 0.3s;
	background: rgba(50, 50, 50, 0);
}

header:hover {
	width: 190px;
	background: rgba(50, 50, 50, 0.95);
}

header:hover div {
	display: inline-block;
}

header div {
	display: none;
	float: left;
	width: 40px;
	height: 40px;
	margin-right: 15px;
	margin-top: 5px;
}

#id-menu {
	display: inline-block;
	margin-top: 0;
	width: 50px;
	height: 50px;
	border-radius: 50%;
	background: url('../img/menu.png');
	background-size: 100% 100%;
	opacity: 0.4;
}

#id-menu:hover {
	opacity: 0.85;
}

#id-wall {
	background: url('../img/wall.png');
	background-size: 100% 100%;
	opacity: 0.4;
}

#id-wall:hover {
	opacity: 0.85;
}

#id-list {
	background: url('../img/list.png');
	background-size: 100% 100%;
	opacity: 0.4;
}

#id-list:hover {
	opacity: 0.7;
}