I'm looking to turn the Category Tab nemu into a dropdown menu. I tried adding this to the css

Code:
  /*START Navigation Category*/

#navCatTabs li {
  /*float the main list items*/
  margin: 0;
  background-color: #339900;
  float: left;
  display: block;
  padding-right: 15px;
}

#navCatTabs li.category-top ul, #navCatTabs li.category-NEXT ul {
  /*hide the subnavs*/
  display: none;
  background-color: #339900;
  position: absolute;
  top: 33px;
  height: 15px;
  left: 0;
  padding-top: 10px;

}

#navCatTabs li a {
  /*for all links in the list*/
  color: #f90;
  font-weight: bold;
  display: block;
  height: 15px;
  width: 100px;
  border: 0px;
  padding: 5px;
}


#navCatTabs li.category-top a {
  /*change border color for active topic area*/
  border: 1px solid #f90;
}

#navCatTabs li.category-top ul a, #nav li.category-NEXT ul a {
  /*  cancel inherit of border
      on subnav of active topic */
  border: 0;
}

#navCatTabs li.category-top ul {
  /*display active subnav list*/
  display: block;
}

#navCatTabs li.category-top ul a, #navCatTabs li.category-NEXT ul a {
  float: left;
  /*ie doesn't inherit the float*/
  border: 0;
  color: #f90;
  width: auto;
  margin-right: 15px;
}

#navCatTabs li.category-top ul {
  /*display the current topic*/
  display: block;
}

#navCatTabs li.category-NEXT:hover ul {
  /*  display the other topics when
      their parent is hovered */
  display: block;
  z-index: 6000;
}

#navCatTabs li.category-NEXT a:hover, #nav li.category-NEXT:hover a {
  background: #339900;
  color: #f90;
}


  /*END OF Navigation Category*/
Still no dropdown. Am I missing something? Do I have to go into the template file?