title: Bootstrap navbar collapse is not working
body: <p>Starting to learn Bootstrap and have a problem... My navbar toggle is not working for some reason...<br>
  Here's my code:</p>
  
  <pre><code>&lt;nav&gt;
          &lt;div class="container"&gt;
              &lt;div class="row"&gt;
  
                  &lt;div class="navbar-header"&gt;
                      &lt;a href="#" class="navbar-brand logo"&gt;
                          &lt;img src="img/logo.png" alt="Logo"&gt;
                      &lt;/a&gt;
  
                      &lt;button class="navbar-toggle collapsed menu_btn" data-toogle="collapse" data-target="#top_menu"&gt;
                          Menu
                      &lt;/button&gt;
                  &lt;/div&gt;
  
                  &lt;div class="collapse navbar-collapse navbar-right" id="top_menu"&gt;
                      &lt;ul class="menu"&gt;
                          &lt;li&gt;&lt;a href="#"&gt;Features&lt;/a&gt;&lt;/li&gt;
                          &lt;li&gt;&lt;a href="#"&gt;Works&lt;/a&gt;&lt;/li&gt;
                          &lt;li&gt;&lt;a href="#"&gt;our team&lt;/a&gt;&lt;/li&gt;
                          &lt;li&gt;&lt;a href="#"&gt;testimoials&lt;/a&gt;&lt;/li&gt;
                          &lt;li&gt;&lt;a href="#"&gt;download&lt;/a&gt;&lt;/li&gt;
                      &lt;/ul&gt;
                  &lt;/div&gt;
              &lt;/div&gt;
              &lt;div class="top_line"&gt;&lt;/div&gt;
          &lt;/div&gt;
      &lt;/nav&gt;
  </code></pre>
  
  <p>Libraries are correct.</p>
  
  <p>Thank you!</p>