title: Change the font type and the background color of navbar menu
body: <p>I have a shiny app and I  would like to change the font typeand the background color of the navbar menu.
  <a href="https://i.stack.imgur.com/8qTjR.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/8qTjR.png" alt="enter image description here"></a></p>
  
  <p>I have used 'Inspect' on this after running the app and I found that this element is:</p>
  
  <pre><code>a href="#" class="dropdown-toggle" data-toggle="dropdown" data-value="More"&gt;
                    More
                    &lt;b class="caret"&gt;&lt;/b&gt;
                  &lt;/a&gt;
  </code></pre>
  
  <p>but im not familiar with css.</p>
  
  <pre><code>ui &lt;- function(){
  
  bootstrapPage('',
  
              navbarPage(title = 'Hello colour changed',
                         navbarMenu("More",
                                    tabPanel("Table"
  
                                    ),
                                    tabPanel("About"
  
                                    )
                         )),
  
              tags$style(type = 'text/css', '.navbar { background-color: #252525;
                         font-family: Arial;
                         font-size: 13px;
                         color: #FF0000; }',
  
                         '.navbar-dropdown { background-color: #252525;
                         font-family: Arial;
                         font-size: 13px;
                         color: #FF0000; }',
  
                         '.navbar-default .navbar-brand {
                         color: #cc3f3e;
              }'
  
              ))
  
              }
  
              server &lt;- function(input, output, session){
              }
  
  
              shinyApp(ui = ui, server = server)
  </code></pre>