点击，弹出登录框

 * {
	margin:0;
	padding:0;
	box-sizing:border-box;
}
h1 {
	display:flex;
	justify-content:center;
}
a {
	color:#000;
	text-decoration:none;
}
.pop {
	font-size:60px;
}
.main {
	display:none;
}
.mask {
	position:fixed;
	top:0;
	width:100%;
	height:100%;
	background-color:rgba(0,0,0,.3);
}
.login-box {
	width:500px;
	height:250px;
	background-color:#fff;
	position:relative;
	top:50%;
	left:50%;
	transform:translate(-50%,-50%);
	box-shadow:1px 1px 15px #fff;
}
.title {
	position:relative;
	text-align:center;
	height:60px;
	line-height:60px;
	cursor:move;
	background-color:aqua;
}
.title .sut {
	position:absolute;
	right:-10px;
	top:-20px;
	content:'关闭';
	width:50px;
	height:50px;
	line-height:50px;
	border-radius:50%;
	background-color:#fff;
	box-shadow:1px 1px 15px #ddd;
}
.input-box {
	position:relative;
	display:flex;
	flex-flow:column;
	justify-content:center;
	margin-top:20px;
}
p {
	width:100%;
	text-align:center;
	margin-bottom:20px;
}
.inp {
	outline:none;
	width:250px;
	height:30px;
	border:1px solid #ccc;
	padding-left:5px;
}
.sub {
	background-color:transparent;
	border:1px solid #ccc;
	width:200px;
	margin:auto;
	font-size:16px;
	padding:10px 0;
	cursor:pointer;
}