Dropdown menu with css

dropdown.css

.menu {
        list-style: none;
        float: left;
        position: relative;
}

.menu li {
        float: left;
        margin-right: 10px;
        position: relative;
}

.menu ul {
        list-style: none;
        position: absolute;
        left: -9999px;
        background: #fff;
        background: rgba(255,255,255,0);
}

.menu a {
        display: block;
        text-decoration: none;
}

.menu li:hover ul {
        left: 0;
}

.menu ul li {
        padding-top: 1px;
        float: none;
}

.menu ul a {
        white-space: nowrap;
}