menu bar problem in mobile devices

[karlcunanan]

Hi web designers! I just want to know what is the problem with my css since its perfectly working in desktop and laptop, while its having a problem in tablets and mobile devices. This is my code:

CSS:

#header{

    width: 935px;
    margin-left: auto;
    margin-right:auto;
    padding:20px;
    background-color:#FFF;
    margin-top:-9px;
}

ul#css3menu1,ul#css3menu1 ul{
    margin:0;list-style:none;padding:0;background-color:#dedede;border-width:1px;border-style:solid;border-color:#5f5f5f;-moz-border-radius:5px;-webkit-border-radius:5px;border-radius:5px;}
ul#css3menu1 ul{
    display:none;position:absolute;left:0;top:100%;-moz-box-shadow:3.5px 3.5px 5px #000000;-webkit-box-shadow:3.5px 3.5px 5px #000000;box-shadow:3.5px 3.5px 5px #000000;background-color:#424542;border-width:2px;border-radius:6px;-moz-border-radius:6px;-webkit-border-radius:6px;border-color:#FFF;padding:0 10px 10px;}
ul#css3menu1 li:hover>*{
    display:block;}
ul#css3menu1 li{
    position:relative;width:139px;display:block;white-space:nowrap;font-size:0;float:left;}
ul#css3menu1 li:hover{
    z-index:1;}
ul#css3menu1{
    font-size:0;z-index:999;position:relative;display:inline-block;zoom:1;padding:0;
    *display:inline;}
* html ul#css3menu1 li a{
    display:inline-block;}
ul#css3menu1>li{
    margin:0;}
ul#css3menu1 a:active, ul#css3menu1 a:focus{
    outline-style:none;}
ul#css3menu1 a{
    display:block;vertical-align:middle;text-align:left;text-decoration:none;font:bold 14px Trebuchet MS;color:#000000;text-shadow:#FFF 0 0 1px;cursor:pointer;padding:10px;background-color:#5289e5;background-image:url("mainbk.png");background-repeat:repeat;background-position:0 0;border-width:0 0 0 1px;border-style:solid;border-color:#C0C0C0;}
ul#css3menu1 ul li{
    float:none;margin:10px 0 0;}
ul#css3menu1 ul a{
    text-align:left;padding:4px;background-color:#424542;background-image:none;border-width:0;border-radius:0px;-moz-border-radius:0px;-webkit-border-radius:0px;font:14px Tahoma;color:#FFF;text-decoration:none;text-shadow:#FFF 0 0 0;}
ul#css3menu1 li:hover>a,ul#css3menu1 li a.pressed{
    background-color:#000000;border-color:#C0C0C0;border-style:solid;color:#ffffff;text-shadow:#FFF 0 0 1px;background-image:url("mainbk.png");background-position:0 100px;text-decoration:none;}
ul#css3menu1 span{
    display:block;overflow:visible;background-position:right center;background-repeat:no-repeat;padding-right:0px;}
ul#css3menu1 ul li:hover>a,ul#css3menu1 ul li a.pressed{
    background-color:#424542;background-image:none;color:#00aaff;text-decoration:none;text-shadow:#FFF 0 0 0;}
ul#css3menu1 li.topfirst>a{
    border-width:0;border-radius:4px 0 0 4px;-moz-border-radius:4px 0 0 4px;-webkit-border-radius:4px;-webkit-border-top-right-radius:0;-webkit-border-bottom-right-radius:0;}
ul#css3menu1 li.toplast>a{
    border-radius:0 4px 4px 0;-moz-border-radius:0 4px 4px 0;-webkit-border-radius:0;-webkit-border-top-right-radius:4px;-webkit-border-bottom-right-radius:4px;}

HTML:

<div id="header">
<center>
  <img style="margin-left:-100px; margin-top:-12px" src="images/header.gif" />
</center>
<a href="http://positiveqa.com:2095/horde/index.php"><img style="float:right; margin-top: -20px; margin-right:15px" src="images/email.png" border="0"/></a>
</div>
<center>
<ul id="css3menu1" class="topmenu">
    <li class="topfirst"><a href="index.php" style="height:18px;line-height:18px;"><center>Home</center></a></li>
    <li class="topmenu"><a href="findjobs.php" style="height:18px;line-height:18px;"><center>Find Jobs</center></a></li>
    <li class="topmenu"><a href="addcv.php" style="height:18px;line-height:18px;"><center>Post CV</center></a></li>
    <li class="topmenu"><a href="#" style="height:18px;line-height:18px;"><span><center>Employers</center></span></a>
    <ul>
        <li><a href="creatjobform.php">Post Job</a></li>
        <li><a href="applicants.php">Search CVs</a></li>
    </ul></li>
    <li class="topmenu"><a href="#" style="height:18px;line-height:18px;"><span><center>Domestic Workers</center></span></a>
    <ul>
<li><a href="domestichelpers/housemaids.php">Housemaid</a></li>
        <li><a href="domestichelpers/houseboy.php">House Boy</a></li>
        <li><a href="domestichelpers/driver.php">Driver</a></li>
        <li><a href="domestichelpers/chef.php">Chef</a></li>
        <li><a href="domestichelpers/others.php">Others</a></li>
    </ul></li>
    <li class="topmenu"><a href="contactusform.php" style="height:18px;line-height:18px;"><center>Contact Us</center></a></li>
    <li class="toplast"><a href="aboutus.php" style="height:18px;line-height:18px;"><center>About Us</center></a></li>
</ul>
</center>

[JorgeM]

What problem are you having with the mobile devices?

[karlcunanan]

The last item in my Menu bar is showing at the bottom of the first item

[JorgeM]

If you are setting a width on the list items and you run out of space, it will wrap to the next line, in this case, under the first item.

[karlcunanan]

Am just wondering why only in mobile device and tablets, in pc's its okay. Anyway I adjusted the width and it went okay :) Thanks JorgeM!