vikunja-frontend/src/styles/labels.scss

.labels-list {
  a, a:hover{
    text-decoration: none;
  }

  .tag{
    margin: 0.5em;
    background: darken($background, 5);

    &.disabled{
      opacity: 0.7;

      &, a {
        cursor: default;
      }
    }
  }
}