Ie 7 & Css

www.freshsunglasses.com



Site works fine in FireFox only.





When I open up the site in IE 6 the right menu is missing.



When the site is loaded in IE 7 the left menu shows up right under the right menu.



I know the problem is in this part of the code:



.left-column {

float:left;

width:180px;

padding-left: 0px; /* left margin /

margin-left:-100%;

background: #ffffff;



}

.right-column {

float:left;

width:180px;

margin-left:-180px; /
Col width + right margin*/

background-color: #ffffff;





}



Can anyone help me figure out how I can make it display the same as in FireFox for IE 6 and 7?