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<?php

/**
 * Twenty Fifteen functions and definitions
 *
 * Set up the theme and provides some helper functions, which are used in the
 * theme as custom template tags. Others are attached to action and filter
 * hooks in WordPress to change core functionality.
 *
 * When using a child theme you can override certain functions (those wrapped
 * in a function_exists() call) by defining them first in your child theme's
 * functions.php file. The child theme's functions.php file is included before
 * the parent theme's file, so the child theme functions would be used.
 *
 * @link https://codex.wordpress.org/Theme_Development
 * @link https://developer.wordpress.org/themes/advanced-topics/child-themes/
 *
 * Functions that are not pluggable (not wrapped in function_exists()) are
 * instead attached to a filter or action hook.
 *
 * For more information on hooks, actions, and filters,
 * {@link https://codex.wordpress.org/Plugin_API}
 *
 * @package WordPress
 * @subpackage Twenty_Fifteen
 * @since Twenty Fifteen 1.0
 */


/**
 * Set the content width based on the theme's design and stylesheet.
 *
 * @since Twenty Fifteen 1.0
 */
if ( ! isset( $content_width ) ) {
  $content_width = 660;
}


/**
 * Twenty Fifteen only works in WordPress 4.1 or later.
 */
if ( version_compare( $GLOBALS['wp_version'], '4.1-alpha', '<' ) ) {
  require get_template_directory() . '/inc/back-compat.php';
}

if ( ! function_exists( 'twentyfifteen_setup' ) ) :
/* function twentyfifteen_setup() – Sets up theme defaults and registers support for various WordPress features. */
endif; // twentyfifteen_setup
add_action( 'after_setup_theme', 'twentyfifteen_setup' );

/* function twentyfifteen_widgets_init() – Register widget area. */
add_action( 'widgets_init', 'twentyfifteen_widgets_init' );

if ( ! function_exists( 'twentyfifteen_fonts_url' ) ) :
/* function twentyfifteen_fonts_url() – Register Google fonts for Twenty Fifteen. */
endif;

/* function twentyfifteen_javascript_detection() – JavaScript Detection. */
add_action( 'wp_head', 'twentyfifteen_javascript_detection', 0 );

/* function twentyfifteen_scripts() – Enqueue scripts and styles. */
add_action( 'wp_enqueue_scripts', 'twentyfifteen_scripts' );

/* function twentyfifteen_block_editor_styles() – Enqueue styles for the block-based editor. */
add_action( 'enqueue_block_editor_assets', 'twentyfifteen_block_editor_styles' );


/* function twentyfifteen_resource_hints() – Add preconnect for Google Fonts. */
add_filter( 'wp_resource_hints', 'twentyfifteen_resource_hints', 10, 2 );

/* function twentyfifteen_post_nav_background() – Add featured image as background image to post navigation elements. */
add_action( 'wp_enqueue_scripts', 'twentyfifteen_post_nav_background' );

/* function twentyfifteen_nav_description() – Display descriptions in main navigation. */
add_filter( 'walker_nav_menu_start_el', 'twentyfifteen_nav_description', 10, 4 );

/* function twentyfifteen_search_form_modify() – Add a `screen-reader-text` class to the search form’s submit button. */
add_filter( 'get_search_form', 'twentyfifteen_search_form_modify' );

/* function twentyfifteen_widget_tag_cloud_args() – Modifies tag cloud widget arguments to display all tags in the same font size
and use list format for better accessibility. */
add_filter( 'widget_tag_cloud_args', 'twentyfifteen_widget_tag_cloud_args' );



/**
 * Implement the Custom Header feature.
 *
 * @since Twenty Fifteen 1.0
 */
require get_template_directory() . '/inc/custom-header.php';


/**
 * Custom template tags for this theme.
 *
 * @since Twenty Fifteen 1.0
 */
require get_template_directory() . '/inc/template-tags.php';

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