Here are the contents of the default DropdownNavigation.css file of Runway module

* Basic code - don't modify */
 #dropdownNavigation { display: block; margin: 0; padding: 0; position: relative; }
  #dropdownNavigation li { display: block; list-style: none; margin: 0 !Important; padding: 0 !Important; float: left; position: relative; }
  #dropdownNavigation a { display: block; }
  #dropdownNavigation ul { display: none; position: absolute; left: 0; margin: 0 !Important; padding: 0 !Important; }
  * html #dropdownNavigation ul { line-height: 0; } /* IE6 "fix" */
      #dropdownNavigation ul a { zoom: 1; } /* IE6/7 fix */
    #dropdownNavigation ul li { float: none; }
    #dropdownNavigation ul ul { top: 20; }
   
/* Essentials - configure this */
#dropdownNavigation ul { width: 160px; }
#dropdownNavigation ul ul { left: 80px; }

/* Everything else is theming */
#dropdownNavigation {height: 24px; }


#dropdownNavigation *:hover { background-color: none; }

#dropdownNavigation a {font-size: 14px; padding: 6px; line-height: 1; }

  #dropdownNavigation li.hover a { background-color: #CED7DE;}

  #dropdownNavigation ul { top: 32px; }
    #dropdownNavigation ul li a { background-color: #CED7DE; }

      #dropdownNavigation ul a.hover { background-color: #426FC8; }
   
   #dropdownNavigation ul a { border-bottom: 1px solid white; border-right: none; opacity: 0.9; filter: alpha(opacity=90); }

/* #dropdownNavigation ul a { border-bottom: none; } - I also needed this for IE6/7 */



I  want to add a a:visited{text-decoration:none;} rule,  that make all the visited menu items go without their underline. Could you bear me a hand? Thanks!