plugin css is not being applied to the page?

Question

I have enqueue the styles in script using the following code.

function libload()
{
    wp_enqueue_style('style_file' , plugin_dir_url(__FILE__).'lib/plugin_styles.css' , array(), '', true);
    wp_enqueue_script('js_file',  plugin_dir_url(__FILE__).'lib/plugin_js.js', array(), null, true);
}

add_action('wp_enqueue_scripts','libload');

The css file is loading correct style files as well. But the styles are not appearing in the firebug inspect elements nor being applied to the page.

The css is the basic one simply a test css.

.addtogunbtn
{
    color:red;
}

but not being applied,.

Answer 1

In wp_enqueue_style()'s 5th parameter is not boolean. Use following code:

function libload()
{
    wp_enqueue_style('style_file' , plugin_dir_url(__FILE__).'lib/plugin_styles.css');
    wp_enqueue_script('js_file',  plugin_dir_url(__FILE__).'lib/plugin_js.js', array(), null, true);
}

add_action('wp_enqueue_scripts','libload');