Change css for li with class active Bootstrap
<p>I use Bootstrap on my page:</p>

<pre><code>&lt;?php echo '&lt;div class="navbar navbar-default" role="navigation"&gt;
&lt;div class="container-fluid"&gt;
    &lt;div class="navbar-header"&gt;
        &lt;button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-collapse"&gt;
            &lt;span class="sr-only"&gt;Toggle navigation&lt;/span&gt;
            &lt;span class="icon-bar"&gt;&lt;/span&gt;
            &lt;span class="icon-bar"&gt;&lt;/span&gt;
            &lt;span class="icon-bar"&gt;&lt;/span&gt;
        &lt;/button&gt;
        &lt;a class="navbar-brand" href="index.php"&gt;Project name&lt;/a&gt;
    &lt;/div&gt;
    &lt;div class="navbar-collapse collapse"&gt;
        &lt;ul class="nav navbar-nav"&gt;
            &lt;li class="active" id="one"&gt;&lt;a href="index.php"&gt;Home&lt;/a&gt;&lt;/li&gt;';?   &gt;
 &lt;?php
 if (isset($_COOKIE['id']) and isset($_COOKIE['hash'])) {
 echo '&lt;li&gt;&lt;a href="logout.php"&gt;Logout&lt;/a&gt;&lt;/li&gt;';
 }
 ?&gt;
 &lt;?php echo '&lt;/ul&gt;
    &lt;/div&gt;
 &lt;/div&gt;
 &lt;/div&gt;';
</code></pre>

<p>I want to change background for li with class active:</p>

<pre><code> li .active{
    background-color: red;
}
</code></pre>

<p>But my code doesn't work</p>