Basic Responsive Header Dropdown Menu With jQuery And CSS3

A responsive dropdown menu for header navigation that utilizes CSS3 media queries to detect the screen size and collapses horizontal menu items into a fullscreen sliding toggle menu when the maximum screen width is reached.

How to use it:

1. Create a multi-level header navigation from a nested nav list as follows:

<header>
  <div class="logo">YOUR LOGO HERE</div>
  <nav>
    <ul>
      <li><a href="#">Home</a></li>
      <li><a href="#">About</a></li>
      <li class="sub-menu"><a href="#">Services</a>
        <ul>
          <li><a href="#">Link 1</a></li>
          <li><a href="#">Link 2</a></li>
          <li><a href="#">Link 3</a></li>
          <li><a href="#">Link 4</a></li>
        </ul>
      </li>
      <li><a href="#">Team</a></li>
      <li class="sub-menu"><a href="#">Portfolio</a>
        <ul>
          <li><a href="#">Link 1</a></li>
          <li><a href="#">Link 2</a></li>
          <li><a href="#">Link 3</a></li>
          <li><a href="#">Link 4</a></li>
        </ul>
      </li>
      <li><a href="#">Contact</a></li>
    </ul>
  </nav>
  <div class="menu-toggle">
    Menu Toggler Here
  </div>
</header>

2. The CSS styles for the regular dropdown menu.

/* Header */
header {
  position: absolute;
  top: 0;
  left: 0;
  padding: 0 100px;
  background: #262626;
  width: 100%;
  box-sizing: border-box;
}

/* LOGO */
header .logo {
  color: #FFF;
  height: 50px;
  line-height: 50px;
  font-size: 24px;
  float: left;
  font-weight: bold;
}

/* Dropdown Nav */
header nav {
  float: right;
}

/* UL */
header nav ul {
  margin: 0;
  padding: 0;
  display: flex;
}

/* Nav Items */
header nav ul li {
  list-style: none;
  position: relative;
}

/* Sub-menu */
header nav ul li.sub-menu:before {
  content: '\f0d7';
  font-family: fontAwesome;
  position: absolute;
  line-height: 50px;
  color: #FFF;
  right: 5px;
  cursor: pointer;
}

header nav ul li.active.sub-menu:before {
  content: '\f0d8';
}

header nav ul li ul {
  position: absolute;
  left: 0;
  background: #333;
  display: none;
}

header nav ul li.active ul {
  display: block;
}

header nav ul li ul li {
  display: block;
  width: 200px;
}

header nav ul li a {
  height: 50px;
  line-height: 50px;
  padding: 0 20px;
  color: #FFF;
  text-decoration: none;
  display: block;
}

header nav ul li a:hover, header nav ul li a.active {
  color: #FFF;
  background: #2196f3;
}

3. The CSS styles for the toggle menu.

/* Toggle Button */
.menu-toggle {
  color: #FFF;
  float: right;
  line-height: 50px;
  font-size: 24px;
  cursor: pointer;
  display: none;
}

/* Media Queries */
@media (max-width: 991px) {
  header {
    padding: 0 20px;
  }

  .menu-toggle {
    display: block;
  }

  header nav {
    position: absolute;
    width: 100%;
    height: calc(100vh - 50px);
    background: #333;
    top: 50px;
    left: -100%;
    transition: 0.5s;
  }

  header nav.active {
    left: 0;
  }

  header nav ul {
    display: block;
    text-align: center;
  }

  header nav ul li a {
    border-bottom: 1px solid rgba(0,0,0,.2);
  }

  header nav ul li.active ul {
    position: relative;
    background: #003e6f;
  }

  header nav ul li ul li {
    width: 100%;
  }
}

4. The core JavaScript to enable the toggle button to open/close the menu when running on small screens.

$(document).ready(function(){
  $('.menu-toggle').click(function(){
    $('nav').toggleClass('active');
  });

  $('ul li').click(function(){
    $(this).siblings().removeClass('active');
    $(this).toggleClass('active');
  })
})

---

This awesome jQuery plugin is developed by leosantosp. For more Advanced Usages, please check the demo page or visit the official website.