Jquery实现顶部弹出框特效_jquery

body {
margin: 0;
padding: 0;
}
.tooltiptop {
width: 100%;
height: 50px;
margin-top:-50px;
display:none;
}
.tooltiptop .bg {
width: 100%;
background-color: #333;
height: 50px;
opacity: .7;
position: absolute;
margin: 0;
}
.tooltiptop .main {
width: 100%;
position: absolute;
margin: 0;
height: 50px;
line-height: 50px;
text-align: center;
color: #fff;
}
.tooltiptop .main span {
float: right;
color: #fff;
margin-right: 20px;
cursor: pointer;
}