<section class="navigation">
  <div class="nav-container">
    <div class="brand">
      <a href="#!">Logo</a>
    </div>
    <nav>
      <div class="nav-mobile"><a id="nav-toggle" href="#!"><span></span></a></div>
      <ul class="nav-list">
        <li>
          <a href="#!">Home</a>
        </li>
        <li>
          <a href="#!">About</a>
        </li>
        <li>
          <a href="#!">Services</a>
          <ul class="nav-dropdown">
            <li>
              <a href="#!">Web Design</a>
            </li>
            <li>
              <a href="#!">Web Development</a>
            </li>
            <li>
              <a href="#!">Graphic Design</a>
            </li>
          </ul>
        </li>
        <li>
          <a href="#!">Pricing</a>
        </li>
        <li>
          <a href="#!">Portfolio</a>
          <ul class="nav-dropdown">
            <li>
              <a href="#!">Web Design</a>
            </li>
            <li>
              <a href="#!">Web Development</a>
            </li>
            <li>
              <a href="#!">Graphic Design</a>
            </li>
          </ul>
        </li>
        <li>
          <a href="#!">Contact</a>
        </li>
      </ul>
    </nav>
  </div>
</section>

<article>
  <h2>Navigation</h2>
  <p>Responsive Dropdown Navigation Bar.</p>
  <p>Want to see how it's made? <a href="http://www.taniarascia.com/responsive-dropdown-navigation-bar/">Read the tutorial!</a></p>
</article>
// Navigation Variables
$content-width: 1000px;
$breakpoint: 799px;
$nav-height: 70px;
$nav-background: #262626;
$nav-font-color: #ffffff;
$link-hover-color: #2581DC;

// Outer navigation wrapper
.navigation {
  height: $nav-height;
  background: $nav-background;
}

// Logo and branding
.brand {
  position: absolute;
  padding-left: 20px;
  float: left;
  line-height: $nav-height;
  text-transform: uppercase;
  font-size: 1.4em;
  a,
  a:visited {
    color: $nav-font-color;
    text-decoration: none;
  }
}

// Container with no padding for navbar
.nav-container {
  max-width: $content-width;
  margin: 0 auto;
}

// Navigation 
nav {
  float: right;
  ul {
    list-style: none;
    margin: 0;
    padding: 0;
    li {
      float: left;
      position: relative;
      a,
      a:visited {
        display: block;
        padding: 0 20px;
        line-height: $nav-height;
        background: $nav-background;
        color: $nav-font-color;
        text-decoration: none;
        &:hover {
          background: $link-hover-color;
          color: $nav-font-color;
        }
        &:not(:only-child):after {
          padding-left: 4px;
          content: ' ▾';
        }
      } // Dropdown list
      ul li {
        min-width: 190px;
        a {
          padding: 15px;
          line-height: 20px;
        }
      }
    }
  }
}

// Dropdown list binds to JS toggle event
.nav-dropdown {
  position: absolute;
  display: none;
  z-index: 1;
  box-shadow: 0 3px 12px rgba(0, 0, 0, 0.15);
}

/* Mobile navigation */

// Binds to JS Toggle
.nav-mobile {
  display: none;
  position: absolute;
  top: 0;
  right: 0;
  background: $nav-background;
  height: $nav-height;
  width: $nav-height;
}
@media only screen and (max-width: 798px) {
  // Hamburger nav visible on mobile only
  .nav-mobile {
    display: block;
  }
  nav {
   width: 100%;
    padding: $nav-height 0 15px;
    ul {
      display: none;
      li {
        float: none;
        a {
          padding: 15px;
          line-height: 20px;
        }
        ul li a {
          padding-left: 30px;
        }
      }
    }
  }
  .nav-dropdown {
    position: static;
  }
}
@media screen and (min-width: $breakpoint) {
  .nav-list {
    display: block !important;
  }
}
#nav-toggle {
  position: absolute;
  left: 18px;
  top: 22px;
  cursor: pointer;
  padding: 10px 35px 16px 0px;
  span,
  span:before,
  span:after {
    cursor: pointer;
    border-radius: 1px;
    height: 5px;
    width: 35px;
    background: $nav-font-color;
    position: absolute;
    display: block;
    content: '';
    transition: all 300ms ease-in-out;
  }
  span:before {
    top: -10px;
  }
  span:after {
    bottom: -10px;
  }
  &.active span {
    background-color: transparent;
    &:before,
    &:after {
      top: 0;
    }
    &:before {
      transform: rotate(45deg);
    }
    &:after {
      transform: rotate(-45deg);
    }
  }
}

// Page content 
article {
  max-width: $content-width;
  margin: 0 auto;
  padding: 10px;
}
View Compiled
(function($) { // Begin jQuery
  $(function() { // DOM ready
    // If a link has a dropdown, add sub menu toggle.
    $('nav ul li a:not(:only-child)').click(function(e) {
      $(this).siblings('.nav-dropdown').toggle();
      // Close one dropdown when selecting another
      $('.nav-dropdown').not($(this).siblings()).hide();
      e.stopPropagation();
    });
    // Clicking away from dropdown will remove the dropdown class
    $('html').click(function() {
      $('.nav-dropdown').hide();
    });
    // Toggle open and close nav styles on click
    $('#nav-toggle').click(function() {
      $('nav ul').slideToggle();
    });
    // Hamburger to X toggle
    $('#nav-toggle').on('click', function() {
      this.classList.toggle('active');
    });
  }); // end DOM ready
})(jQuery); // end jQuery

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

  1. https://cdnjs.cloudflare.com/ajax/libs/jquery/2.1.3/jquery.min.js