div顶部悬浮,不随滚动条滚动

.status{
    background: #4d4d4d none repeat scroll 0 0;
    color: #e6e6e6;
    height: 30px;
    line-height: 30px;
    width: 100%;
    border-bottom: 1px solid #ccc;
    position: fixed;
    top: 0px;
}