add_action( 'after_setup_theme', 'child_theme_setup', 20 );

function child_theme_setup() {
    remove_shortcode( 'fullscreen_slider' );
    add_shortcode( 'fullscreen_slider', 'my_fullscreen_slider' );
}

function my_fullscreen_slider($attributes, $content = null)
    {
        $attributes = shortcode_atts(
            array(
                'interval' => 5000,
                'transition' => 2,
                'speed' => 400,
            ), $attributes);

        global $first_slide;
        $first_slide = TRUE;

        $interval = (is_numeric($attributes['interval']))?round($attributes['interval']):5000;
        $speed = (is_numeric($attributes['speed']))?round($attributes['speed']):400;
        $transition = (in_array($attributes['transition'], array(0, 1, 2, 3, 4, 5, 6, 7)))?$attributes['transition']:2;

        $output = '<div class="us_supersized">
                        <a id="prevslide" class="load-item"><i class="fa fa-chevron-left"></i></a>
                        <a id="nextslide" class="load-item"><i class="fa fa-chevron-right"></i></a>
                        <div class="slidecaption">
                            <div id="slidecaption"></div>
                        </div>
                        <ul id="slide-list"></ul>
                    </div>
                    <script type="text/javascript">
                        jQuery(document).ready(function() {
                            jQuery.supersized({
                                // Functionality
                                slide_interval : '.$interval.', // Length between transitions
                                transition : '.$transition.', // 0-None, 1-Fade, 2-Slide Top, 3-Slide Right, 4-Slide Bottom, 5-Slide Left, 6-Carousel Right, 7-Carousel Left
                                transition_speed : '.$speed.', // Speed of transition
                                slide_links :   "blank",
                                // Components
                                slides  : [ // Slideshow Images
                                    '.do_shortcode($content).'
                                ]
                            });
                        });
                    </script>
                    <style>
                        ul#slide-list {
                            padding: 15px 0;
                            float: left;
                            position: absolute;
                            left: 50%;
                            bottom: 0;
                        }

                        ul#slide-list li {
                            list-style: none;
                            width: 12px;
                            height: 12px;
                            float: left;
                            margin: 0 5px 0 0;
                        }

                        ul#slide-list li.current-slide a, ul#slide-list li.current-slide a:hover {
                            background-color: grey;
                        }

                        ul#slide-list li a {
                            display: block;
                            width: 12px;
                            height: 12px;
                            background-color: white;
                            border-radius: 50%;
                        }

                        ul#slide-list li a:hover {
                            background-color: grey;
                            cursor: pointer;
                        }
                    </style>';


        return $output;
    }