CSS - Get last child with a specefic class

Question

I'm working on a TAB and wanted to set some CSS on the last

which having 'enable' class.

HTML:

<ul class="tab-navigations__menu" role="tablist">
    <li role="tab" id="savedItemTitle" class="ring-navigations__menu___item enable tSelected" aria-controls="tab1" aria-selected="true" tabindex="0">
        Tab 1
    </li>
    <li role="tab" id="savedEngTitle" class="ring-navigations__menu___item" aria-controls="tab2" aria-selected="false" tabindex="0">
        Tab 2
    </li>
    <li role="tab" id="cartItemTitle" class="ring-navigations__menu___item enable" aria-controls="tab3" aria-selected="false" tabindex="0">
        Tab 3
    </li>
    <li role="tab" id="rrTitle" class="ring-navigations__menu___item" aria-controls="tab4" aria-selected="false" tabindex="0">
        Tab 4
    </li>
</ul>

CSS:

.tab-navigations__menu{
  border-bottom: 1px solid #757575;
  margin: -1px 0 20px;
}
.ring-navigations__menu___item{
  display: none;
  position: relative;
  float: left;
  padding: 20px 0;
  margin-right: 25px;
  color: #000;
  cursor: pointer;
  border-bottom: 2px solid transparent;
}
.ring-navigations__menu___item.enable {
    display:block;
}
.ring-navigations__menu___item.tSelected {
  font-size: 1.2rem;
  line-height: 16px;
  font-weight: 700;
  border-bottom-color: #000;
}

What I tried -

.ring-navigations__menu___item.enable:last-child{
   margin-right: 0;
}

Which is not working!!