What is wrong with this menu?

Has me stumped but since I added to my page everything below it gets sucked upwards and top margin or padding does not help it.
Maybe there is something wrong, it has me stumped.

I have various images i the "a" link as a background image, simple tab menu with images.

Code:

---

ul#mainnav{float:right;
                margin:0px;
                padding:0px;
                list-style-type:none;
                text-transform:uppercase;
                background:#000033;
                font-family:Helvetica,Arial,Verdana,sans-serif;
                }

ul#mainnav li {
    float:left;
    display: inline;
    }

ul#mainnav li a {
    width:192px;
    height: 30px;
    display: block;
    background-position:center;
    color: #ffffff;
    text-decoration: none;
    font-size: 11px;
    padding-top: 10px;
    text-align: center;
    font-weight: bold;
  }

#current1 a {background-image: url('tab1.png');color: #ffffff;}
#current2 a {background-image: url('tab2.png');color: #ffffff;}
#current3 a {background-image: url('tabhome.png');color: #ffffff;}               
#current4 a {background-image: url('tabhome.png');color: #ffffff;}
#current5 a {background-image: url('tabhome.png');color: #ffffff;}

---

The "float" attribute of an element causes this. I don't exactly know why, but it's caused me to cease using "float" altogether. There was a site I found ages back that offered a fix for the issue, but I can't seem to find it now.

All I can suggest for now would be to use the "clear" attribute.

Example:

Code:

---

ul#mainnav li
{
float:left;
display: inline;
clear: both;               
}

---

yes must clear

mjwebsolutionshttp://www.themjwebsolutions.com

Learn how to use clear and float effectively. They're vital to a good developer.

Floats are tricky.

CSS FLOAT property (similar to position: absolute) partially takes element out of normal HTML flow of elements.

See, for instance,
http://coding.smashingmagazine.com/2...loat-property/

Quote:

---

Non-positioned, non-floated, block-level elements act as if the floated element is not there, since the floated element is out of flow in relation to other block elements

---

http://css-tricks.com/all-about-floats/
http://coding.smashingmagazine.com/2...u-should-know/
http://www.w3schools.com/css/css_float.asp

Thanks