CSS: complex menu

by gabrieleromanato

HTML

<div id="navigation">
    <ul>
        <li id="home">
            <a href="#">Home</a>
        </li>
        <li id="about">
            <a href="#">About</a>
        </li>
        <li id="contact">
            <a href="#">Contacts</a>
        </li>
    </ul>
</div>

CSS

#navigation {
    margin: 2em auto;
    width: 425px;
    height: 282px;
    background: url(https://lh4.googleusercontent.com/-kRgsZo7nuB0/T1MrbGVcPdI/AAAAAAAAA3o/dwthcyWMr0s/s425/doubt-confusion.jpg) no-repeat;
}

#navigation ul {
    margin: 0;
    padding: 0;
    list-style: none;
    width: 100%;
    height: 100%;
    position: relative;
}

#navigation li {
    width: 141px;
    height: 95px;
    position: absolute;
}

#navigation a {
    display: block;
    width: 100%;
    height: 100%;
    text-align: center;
    background: rgba(0, 0, 0, 0.8);
    color: #fff;
    text-decoration: none;
    -moz-transition: all 500ms ease-in;
    -webkit-transition: all 500ms ease-in;
    -o-transition: all 500ms ease-in;
    -ms-transition: all 500ms ease-in;
    transition: all 500ms ease-in;
    text-transform: uppercase;
    font: 76%/94px Arial, sans-serif;
    letter-spacing: 2px;
}

#navigation a:hover {
    background: rgba(0, 0, 0, 1);
}

#navigation #home {
    top: 0;
    left: 0;
    width: 143px;
}

#navigation #contact {
    bottom: 0;
    right: 0;
}

#navigation #about {
    top: 50%;
    left: 50%;
    margin: -47px 0 0 -70px;
}