JSFiddle - React, Tailwind, and code Playground

HTML

<!-- end .header-row clearfix -->   

   <div id="main">
      <div class="main-navigation">
<div id="wizemenu" class="menu-top-menu-container"><ul id="menu-top-menu" class="menu"><li id="menu-item-744" class="menu-item menu-item-type-post_type menu-item-object-page current-menu-item page_item page-item-420 current_page_item active"><a href="http://www.radiolimadejuerga.com/">Portada</a></li>
<li id="menu-item-748" class="menu-item menu-item-type-custom menu-item-object-custom"><a href="#">Eventos</a></li>
<li id="menu-item-749" class="rock menu-item menu-item-type-custom menu-item-object-custom"><a href="#">Zona Rock</a></li>
<li id="menu-item-750" class="discos menu-item menu-item-type-custom menu-item-object-custom"><a href="#">Discotecas</a></li>
<li id="menu-item-751" class="bares menu-item menu-item-type-custom menu-item-object-custom"><a href="#">Bares</a></li>
<li id="menu-item-752" class="contacto menu-item menu-item-type-custom menu-item-object-custom"><a href="#">Contacto</a></li>
</ul></div>	

      </div><!-- end .main-navigation -->	

   </div><!-- end #main -->

CSS

#menu-item-748 {
background-color: red;
}

#menu-item-749 {
background-color: green;
}

#menu-item-750 {
background-color: purple;
}

#menu-item-751 {
background-color: blue;
}

#menu-item-752 {
background-color: brown;
}