pak Oil menu

HTML

<div id='main_menu'>
    <ul style='
    list-style: none;'>                          
        <li><a href="/pakoil_index.php">Home</a></li>
                <li><a href="/pakoil_jobs_index.php">Jobs</a></li>
        <li><a href="/pakoil_internship_index.php">Internships</a></li>
                <li><a href="/pakoil_mt_index.php">Management Trainee Program</a></li>
            </ul>
</div>

CSS

#main_menu{
background-color: #F4F4F4;
color: #000000;
border-radius: 0;
border-bottom: solid 1px #ccc; position: relative;
height: 40px;
line-height:40px;
}
#main_menu ul {
     padding-left:5px;
    margin-left: -5px;
    list-style: none;
}

#main_menu ul > li {
    display: inline-block;
    padding-right: 5px;
    padding-left: 5px;
    list-style: none;
}

#main_menu ul > li >a {
    color:black;
    text-decoration:none;
}