nespaint/sass/tabs.scss

.tabnav { 
  color: $tabnav-text;
  padding: 0;
  
  ul {
    margin: 0;
    padding: 0;
  }

  li {
    background-color: $tabnav-bg; 
    display: inline;
    border-top-left-radius: 10px;
    border-top-right-radius: 10px;

    &.tab-selected {
      background-color: $tabnav-content-bg;
      color: $tabnav-content-text;
    }
  }

  a {  
    color: inherit;
    padding: 0 10px;
    text-decoration: none; 
  }

  div.tab-content {
    background-color: $tabnav-content-bg;
    color: $tabnav-content-text;
    padding: 1.25em 0.75em 0.5em 0.75em
  }
}