Add css or html in footer through Wordpress function

Add css or html in footer through Wordpress function
                     OR
Add javascript and CSS to footer with wordpress function

paste this line into funciton.php of your theme

add_action('wp_footer', 'add_css');
function add_css() {
your css here //dont forget to close php tag before <style> tag and start after </style> tag
}
Solution 2 --
------------------------------------------------------
// Load the theme stylesheets
function theme_styles() 
{

    // Example of loading a jQuery slideshow plugin just on the homepage
    wp_register_style( 'flexslider', get_template_directory_uri() . '/css/flexslider.css' );

    // Load all of the styles that need to appear on all pages
    wp_enqueue_style( 'main', get_template_directory_uri() . '/style.css' );
    wp_enqueue_style( 'custom', get_template_directory_uri() . '/css/custom.css' );

    // Conditionally load the FlexSlider CSS on the homepage
    if(is_page('home')) {
        wp_enqueue_style('flexslider');
    }

}
add_action('wp_enqueue_scripts', 'theme_styles');