Triangles for bootstrap dropdown menus

bootstrap-menu-triangles.css

  .dropdown-menu::before {
    border-bottom: 9px solid rgba(0, 0, 0, 0.2);
    border-left: 9px solid rgba(0, 0, 0, 0);
    border-right: 9px solid rgba(0, 0, 0, 0);
    content: "";
    display: inline-block;
    left: 86px;
    position: absolute;
    top: -8px;
}
  .dropdown-menu::after {
    border-bottom: 8px solid #FFFFFF;
    border-left: 9px solid rgba(0, 0, 0, 0);
    border-right: 9px solid rgba(0, 0, 0, 0);
    content: "";
    display: inline-block;
    left: 86px;
    position: absolute;
    top: -7px;
  }