diff --git a/README.md b/README.md
index eb7885d..504f598 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,8 @@
 
 [![Maintainability](https://api.codeclimate.com/v1/badges/767420930abd5ede9110/maintainability)](https://codeclimate.com/github/chemiker/e.nigma-2015/maintainability) [![Build Status](https://travis-ci.com/chemiker/e.nigma-2015.svg?branch=master)](https://travis-ci.com/chemiker/e.nigma-2015)
 
+![e.nigma 2015](https://github.com/chemiker/e.nigma-2015/raw/master/src/theme/screenshot.png)
+
 ## Installation
 
 1. Download or clone the repository
@@ -21,6 +23,9 @@
 
 ## Changelog
 
+### 1.2.5
+* Further improvements in the codebase (replaced custom functions with WordPress build-in alternatives)
+
 ### 1.2.4
 * Improved support for WordPress/Gutenberg blocks
 * Improved sanitizing outputs
diff --git a/src/sass/form.scss b/src/sass/form.scss
index ad11275..75af106 100644
--- a/src/sass/form.scss
+++ b/src/sass/form.scss
@@ -1,7 +1,8 @@
 /* -------------------------------- Search & Form Elements */
 
 input,
-textarea {
+textarea,
+button {
 	font: 20px/1.5 $sans;
 	color: $darkbeige;
 	padding: 5px 10px 5px 10px;
@@ -31,7 +32,8 @@ input[type=search] {
 	-webkit-appearance: none;
 }
 
-input[type=submit] {
+input[type=submit],
+button {
 	cursor: pointer;
 	color: #7a7a7a;
 	
diff --git a/src/sass/navigation.scss b/src/sass/navigation.scss
index b172518..3a7d1c2 100644
--- a/src/sass/navigation.scss
+++ b/src/sass/navigation.scss
@@ -90,14 +90,18 @@ header {
 	}
 }
 
-div.pagebar {
+div.nav-links {
+	margin-top: -66px;
+}
+
+div.pagebar,
+div.nav-links {
 	color: $darkbeige;
 	text-align: center;
 	padding: 80px 0 100px 0;
 	font-size: 0.8em;
 	border-top: 7px solid $darkbeige;
 	background-color: $beige;
-	margin-top: -66px;
 
 	&.sitepages {
 		margin-top: 0px;
@@ -119,16 +123,14 @@ div.pagebar {
 		display: inline-block;
 	}
 
-	span.page-numbers,
-	a.page-numbers {
-		font-size: 1.3em;
-		margin-right: 5px;
-	}
-
 	span.page-numbers {
 		color: $navigationbackground;
-		background-color: $darkbeige;
+		background-color: $beige;
 		border: 3px solid $navigationbackground;
+
+		&.dots {
+			border-width: 0px;
+		}
 	}
 
 	&.comment {
@@ -154,11 +156,17 @@ div.pagebar {
 			color: $beige;
 			background-color: $navigationbackground;
 			border: 3px solid $beige;
+
+			&:hover {
+				color: $navigationbackground;
+				border-color: $navigationbackground;
+				background-color: $beige;
+			}
 		}
 
 		&:hover,
-		&.active,
-		&.active:visited,
+		.active,
+		.active:visited,
 		&.page:hover,
 		&.page:focus,
 		&.next.page-numbers,
@@ -168,26 +176,19 @@ div.pagebar {
 			background-color: $beige;
 		}
 
-		&.page-numbers,
-		&.page-numbers:visited {
-			margin-right: 5px;
-			background-color: $darkbeige;
-		}
-
 		&.next.page-numbers,
 		&.prev.page-numbers {
-			font-size: 1.3em;
 			border: none;
 			display: inline;
 			font-weight: normal;
-			color: $beige;
-			background-color: $darkbeige;
+			color: $darkbeige;
+			background-color: none;
 		}
 	}
 }
 
 span.pagebar-category {
-	top: -30px !important;
+	top: 5px !important;
 }
 
 span.pagebar-category,
diff --git a/src/theme/comments.php b/src/theme/comments.php
index 05cfa2f..dca111a 100644
--- a/src/theme/comments.php
+++ b/src/theme/comments.php
@@ -28,4 +28,5 @@
 			</ol>
 		</div>
 	</aside>
-<?php endif;
+	<?php
+endif;
diff --git a/src/theme/functions.php b/src/theme/functions.php
index d714ed5..63d5568 100755
--- a/src/theme/functions.php
+++ b/src/theme/functions.php
@@ -10,7 +10,6 @@
  */
 
 require 'functions/class-content.php';
-require 'functions/class-helper.php';
 require 'functions/class-widgets.php';
 require 'functions/class-customizer.php';
 
@@ -130,23 +129,20 @@ function ( $return, $data, $url ) {
 	3
 );
 
-// Add next and number option to wp_link_pages().
-add_filter( 'wp_link_pages_args', '\enigma\Helper::add_next_and_number' );
-
 add_action(
 	'wp_enqueue_scripts',
 	function () {
-		wp_enqueue_script( 'bootstrap', get_template_directory_uri() . '/js/bootstrap.min.js', array( 'jquery' ), '1.2.4', true );
-		wp_enqueue_script( 'jquery-scrollupformenu', get_template_directory_uri() . '/js/jquery.scrollupformenu.min.js', array( 'jquery' ), '1.2.4', true );
-		wp_enqueue_script( 'jquery-enigma', get_template_directory_uri() . '/js/jquery.enigma.min.js', array( 'jquery' ), '1.2.4', true );
+		wp_enqueue_script( 'bootstrap', get_template_directory_uri() . '/js/bootstrap.min.js', array( 'jquery' ), '1.2.5', false );
+		wp_enqueue_script( 'jquery-scrollupformenu', get_template_directory_uri() . '/js/jquery.scrollupformenu.min.js', array( 'jquery' ), '1.2.5', false );
+		wp_enqueue_script( 'jquery-enigma', get_template_directory_uri() . '/js/jquery.enigma.min.js', array( 'jquery' ), '1.2.5', false );
 	}
 );
 
 add_action(
 	'wp_enqueue_scripts',
 	function () {
-		wp_enqueue_style( 'style', get_template_directory_uri() . '/css/screen.min.css', array( 'dashicons' ), '1.2.4', 'screen' );
-		wp_enqueue_style( 'style-print', get_template_directory_uri() . '/css/print.min.css', array( 'dashicons' ), '1.2.4', 'print' );
-		wp_enqueue_style( 'google-fonts', '//fonts.googleapis.com/css?family=Raleway:100%7CRoboto+Slab:400,700%7COpen+Sans:400italic,400,700', array(), '1.2.4' );
+		wp_enqueue_style( 'style', get_template_directory_uri() . '/css/screen.min.css', array( 'dashicons' ), '1.2.5', 'screen' );
+		wp_enqueue_style( 'style-print', get_template_directory_uri() . '/css/print.min.css', array( 'dashicons' ), '1.2.5', 'print' );
+		wp_enqueue_style( 'google-fonts', '//fonts.googleapis.com/css?family=Raleway:100%7CRoboto+Slab:400,700%7COpen+Sans:400italic,400,700', array(), '1.2.5' );
 	}
 );
diff --git a/src/theme/functions/class-content.php b/src/theme/functions/class-content.php
index 7b89c8e..5109d73 100644
--- a/src/theme/functions/class-content.php
+++ b/src/theme/functions/class-content.php
@@ -15,75 +15,11 @@
  * Prefetches content and provides it to the theme templates.
  */
 class Content {
-	/**
-	 * Pagebar Clone, originally created by [Sergej Müller](https://sergejmueller.github.io).
-	 * 
-	 * @param  integer $displayedpages Number of displayed pages.
-	 */
-	public static function pagebar( $displayedpages = 6 ) {
-		global $wp_query;
-		$max_num_pages = $wp_query->max_num_pages;
-
-		if ( $max_num_pages <= 1 ) {
-			return;
-		}
-
-		$page         = (int) get_query_var( 'paged' );
-		$roundedrange = ceil( $displayedpages / 2 );
-
-		if ( ! $page ) {
-			$page = 1;
-		}
-
-		if ( $max_num_pages > $displayedpages ) {
-			if ( $page <= $displayedpages ) {
-				$min = 1;
-				$max = $displayedpages + 1;
-			} elseif ( $page >= ( $max_num_pages - $roundedrange ) ) {
-				$min = $max_num_pages - $displayedpages;
-				$max = $max_num_pages;
-			} elseif ( $page >= $displayedpages && $page < ( $max_num_pages - $roundedrange ) ) {
-				$min = $page - $roundedrange;
-				$max = $page + $roundedrange;
-			}
-		} else {
-			$min = 1;
-			$max = $max_num_pages;
-		}
-
-		if ( ! empty( $min ) && ! empty( $max ) ) {
-			for ( $i = $min; $i <= $max; $i++ ) {
-				echo sprintf(
-					' <a href="%s" %s>%d</a>',
-					get_pagenum_link( $i ),
-					( $i === $page ? 'class="page active"' : 'class="page"' ),
-					$i
-				);
-			}
-		}
-	}
-
 	/**
 	 * Get_categories() fetches the post categories and provides them to the theme templates.
 	 */
 	public static function get_categories() {
-		$thecategories      = get_the_category();
-		$numberofcategories = count( $thecategories );
-		$categories         = '';
-
-		foreach ( $thecategories as $categorienumber => $category ) {
-			if ( $categorienumber === $numberofcategories - 1 ) {
-				$spacer = '';
-			} else {
-				$spacer = ', ';
-			}
-			$categories .= sprintf(
-				'<a href="%s">%s</a>%s',
-				get_category_link( $category->term_id ),
-				$category->name,
-				$spacer
-			);
-		}
+		$categories = get_the_category_list( ', ' );
 
 		if ( ! empty( $categories ) ) {
 			$categories = sprintf(
@@ -228,7 +164,9 @@ private static function get_content( $format ) {
 			return ( $oembed ? $oembed : get_post_meta( get_the_ID(), '_format_' . $format . '_embed', true ) ) . $content;
 		}
 
-		if ( 'image' === $format && $featured_image = wp_get_attachment_image_src( get_post_thumbnail_id(), 'full' ) ) {
+		$featured_image = wp_get_attachment_image_src( get_post_thumbnail_id(), 'full' );
+
+		if ( $featured_image && 'image' === $format ) {
 			return '<img class="hide" src="' . $featured_image[0] . '" alt="' . get_the_title() . '" />' . $content;
 		}
 
@@ -258,7 +196,9 @@ private static function get_class( $format, $class = '' ) {
 	 * @return string
 	 */
 	private static function get_css( $format, $css = '' ) {
-		if ( 'image' === $format && $featured_image = wp_get_attachment_image_src( get_post_thumbnail_id(), 'full' ) ) {
+		$featured_image = wp_get_attachment_image_src( get_post_thumbnail_id(), 'full' );
+
+		if ( $featured_image && 'image' === $format ) {
 			$css = "style=\"background-image: url( '" . $featured_image[0] . "' )\"";
 		}
 
diff --git a/src/theme/functions/class-customizer.php b/src/theme/functions/class-customizer.php
index 534fe6f..7e9443a 100644
--- a/src/theme/functions/class-customizer.php
+++ b/src/theme/functions/class-customizer.php
@@ -60,7 +60,9 @@ public static function register( $wp_customize ) {
 			array(
 				'default'           => __( 'Welcome to my blog', 'e.nigma-2015' ),
 				'type'              => 'theme_mod',
-				'sanitize_callback' => function ( $input ) { return wp_kses_post( $input ); }
+				'sanitize_callback' => function ( $input ) {
+					return wp_kses_post( $input );
+				},
 			)
 		);
 
diff --git a/src/theme/functions/class-helper.php b/src/theme/functions/class-helper.php
deleted file mode 100644
index 5257719..0000000
--- a/src/theme/functions/class-helper.php
+++ /dev/null
@@ -1,49 +0,0 @@
-<?php
-/**
- * Helper class
- *
- * @package WordPress
- * @subpackage e.nigma-2015
- * @since e.nigma-2015 1.0.0
- */
-
-namespace enigma;
-
-/**
- * Widget class
- *
- * Provides function for registering the sidebar.
- */
-class Helper {
-	/**
-	 * Add_next_and_number() changes the appearance of pagelinks, originally found at http://www.velvetblues.com/web-development-blog/wordpress-number-next-previous-links-wp_link_pages/
-	 * 
-	 * @param array $args Arguments such as previouspagelink etc..
-	 */
-	public static function add_next_and_number( $args ) {
-		global $page, $numpages, $multipage, $more;
-
-		if ( ! $multipage || ! $more || 'next_and_number' !== $args['next_or_number'] ) {
-			return $args;
-		}
-
-		$args['next_or_number'] = 'number';
-		$prev                   = ''; 
-		$next                   = '';
-
-		$i     = $page - 1;
-		$prev .= _wp_link_page( $i );
-		$prev .= $args['link_before'] . $args['previouspagelink'] . $args['link_after'] . '</a>';
-
-		$i = $page + 1;
-		if ( $i <= $numpages ) {
-			$next .= _wp_link_page( $i );
-			$next .= $args['link_before'] . $args['nextpagelink'] . $args['link_after'] . '</a>';
-		}
-
-		$args['before'] = $args['before'] . ( 1 === $page ? '' : $prev );
-		$args['after']  = $next . $args['after'];    
-
-		return $args;
-	}
-}
diff --git a/src/theme/index.php b/src/theme/index.php
index 393f8fd..f6820b8 100755
--- a/src/theme/index.php
+++ b/src/theme/index.php
@@ -48,13 +48,15 @@
 if ( $wp_query->max_num_pages > 1 ) :
 	?>
 	<span class="category pagebar-category enigma-icon" data-icon="&#62256;"></span>
-	<div class="pagebar">
-		<?php
-		previous_posts_link();
-		\enigma\Content::Pagebar();
-		next_posts_link(); 
-		?>
-	</div>
+	<?php
+	the_posts_pagination(
+		array(
+			'type'      => 'plain',
+			'prev_text' => '&laquo; ' . esc_html__( 'Previous page', 'e.nigma-2015' ),
+			'next_text' => esc_html__( 'Next page', 'e.nigma-2015' ) . ' &raquo;',
+		)
+	);
+	?>
 	<?php
 endif;
 ?>
diff --git a/src/theme/readme.txt b/src/theme/readme.txt
index cb991f3..88dff21 100644
--- a/src/theme/readme.txt
+++ b/src/theme/readme.txt
@@ -24,6 +24,9 @@ If using the "image" post-type it is recommended to set the image you want to sh
 
 ## Changelog
 
+### 1.2.5
+* Further improvements in the codebase (replaced custom functions with WordPress build-in alternatives)
+
 ### 1.2.4
 * Improved support for WordPress/Gutenberg blocks
 * Improved sanitizing outputs
diff --git a/src/theme/single.php b/src/theme/single.php
index 599ef95..58e77c5 100755
--- a/src/theme/single.php
+++ b/src/theme/single.php
@@ -26,19 +26,7 @@
 		<?php echo apply_filters( 'the_content', $post_vars['content'] ); ?>
 		<?php if ( $numpages > 1 ) : ?>
 		<div class="pagebar sitepages">
-			<?php
-			wp_link_pages(
-				array(
-					'before'           => '',
-					'after'            => '',
-					'nextpagelink'     => esc_html__( 'Next Page &raquo;', 'e.nigma-2015' ),
-					'previouspagelink' => esc_html__( '&laquo; Previous Page', 'e.nigma-2015' ),
-					'next_or_number'   => 'next_and_number',
-					'pagelink'         => '%',
-					'echo'             => 1,
-				)
-			);
-			?>
+			<?php wp_link_pages(); ?>
 		</div>
 		<?php endif; ?>
 		<div class="post-meta">
diff --git a/src/theme/style.css b/src/theme/style.css
index 916f38c..26ff935 100755
--- a/src/theme/style.css
+++ b/src/theme/style.css
@@ -2,7 +2,7 @@
 Theme Name: e.nigma 2015
 Description: e.nigma 2015 is a light-weight, modern and simple WordPress theme. It is thought to be used with WordPress posts formats.
 Author: Alexander Lüken
-Version: 1.2.4
+Version: 1.2.5
 Theme URI: https://sciolism.de/projects/e.nigma-2015/
 Author URI: https://sciolism.de
 Tested up to: 5.6