Bootstrap Nested Dropdown

By adding a few lines of additional CSS you can add extra levels of submenu to your dropdown. You can apply this to the dropdown in a simple button or within the navbar.

To learn more about dropdowns read Dropdown Docs.

Button dropdown

An example of a nested dropdown with a simple button.

HTML

<div class="dropdown">
  <button
    class="btn btn-primary dropdown-toggle"
    type="button"
    id="dropdownMenuButton"
    data-mdb-toggle="dropdown"
    aria-expanded="false"
  >
    Dropdown button
  </button>
  <ul class="dropdown-menu" aria-labelledby="dropdownMenuButton">
    <li><a class="dropdown-item" href="#">Action</a></li>
    <li>
      <a class="dropdown-item" href="#">Another action</a>
    </li>
    <li>
      <a class="dropdown-item" href="#">
        Submenu &raquo;
      </a>
      <ul class="dropdown-menu dropdown-submenu">
        <li>
          <a class="dropdown-item" href="#">Submenu item 1</a>
        </li>
        <li>
          <a class="dropdown-item" href="#">Submenu item 2</a>
        </li>
        <li>
          <a class="dropdown-item" href="#">Submenu item 3 &raquo; </a>
          <ul class="dropdown-menu dropdown-submenu">
            <li>
              <a class="dropdown-item" href="#">Multi level 1</a>
            </li>
            <li>
              <a class="dropdown-item" href="#">Multi level 2</a>
            </li>
          </ul>
        </li>
        <li>
          <a class="dropdown-item" href="#">Submenu item 4</a>
        </li>
        <li>
          <a class="dropdown-item" href="#">Submenu item 5</a>
        </li>
      </ul>
    </li>
  </ul>
</div>

CSS

.dropdown-menu li {
  position: relative;
}
.dropdown-menu .dropdown-submenu {
  display: none;
  position: absolute;
  left: 100%;
  top: -7px;
}
.dropdown-menu .dropdown-submenu-left {
  right: 100%;
  left: auto;
}
.dropdown-menu > li:hover > .dropdown-submenu {
  display: block;
}

Much more examples and a detailed description can be found at 📄 Nested Dropdown documentation page