Converting a regular menu into a bootstrap dropdown menu?

Question

I am looking to change my navbar to have dropdown options, but I have been unable to do this without completely destroying my code and the responsiveness of bootstrap. Resizing doesn't work when I change my code and the css is completely ruined. Here is my code:

<header>
    <div class="container">
        <div class="logo">
            <a href="index.html"><img src="assets/img/resultheap-logo.png" alt="" /></a>
        </div>
        <div class="menu">
            <ul>
                <li><a href="about.html">About</a></li>
                <li><a href="services.html">Services</a></li>
                <li><a href="Blog/index.html">Blog</a></li>
                <li><a href="faq.html">FAQ</a></li>
                <li><a href="contact-form/index.html">Contact</a></li>
            </ul>
        </div>
        <div class="mobile-menu"><i class="fa fa-bars"></i></div>
    </div>
</header>

Answer 1

The Bootstrap documentation shows an example of a menu with a dropdown item:

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <a class="navbar-brand" href="#">Navbar</a>
  <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNavDropdown" aria-controls="navbarNavDropdown" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>
  <div class="collapse navbar-collapse" id="navbarNavDropdown">
    <ul class="navbar-nav">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Features</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Pricing</a>
      </li>
      <li class="nav-item dropdown">
        <a class="nav-link dropdown-toggle" href="#" id="navbarDropdownMenuLink" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
          Dropdown link
        </a>
        <div class="dropdown-menu" aria-labelledby="navbarDropdownMenuLink">
          <a class="dropdown-item" href="#">Action</a>
          <a class="dropdown-item" href="#">Another action</a>
          <a class="dropdown-item" href="#">Something else here</a>
        </div>
      </li>
    </ul>
  </div>
</nav>

Have you tried something similar?