Change css for li with class active Bootstrap

Question

I use Bootstrap on my page:

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

I want to change background for li with class active:

 li .active{
    background-color: red;
}

But my code doesn't work

Answer 1

Try

.navbar-default .navbar-nav > .active{
  color: #000; background: red;
}
.navbar-default .navbar-nav > .active > a, 
.navbar-default .navbar-nav > .active > a:hover, 
.navbar-default .navbar-nav > .active > a:focus {
  color: #000;
  background: red;
}

Answer 2

remove space between li . active changed li.active elements

css

 li.active{
    background-color: red;
}

Demo

Answer 3

You can use this code.

li.active{
    background-color: red;
}

Answer 4

Please try it :

li.active{
    background-color: red !important;
}