diff --git a/lib/jekyll/kroki.rb b/lib/jekyll/kroki.rb
index ddc2923..76f7398 100644
--- a/lib/jekyll/kroki.rb
+++ b/lib/jekyll/kroki.rb
@@ -11,167 +11,165 @@
 require "zlib"
 
 module Jekyll
-  # Converts diagram descriptions into images using Kroki
-  class Kroki
-    KROKI_DEFAULT_URL = "https://kroki.io"
-    SUPPORTED_LANGUAGES = %w[actdiag blockdiag bpmn bytefield c4plantuml d2 dbml diagramsnet ditaa erd excalidraw
-                             graphviz mermaid nomnoml nwdiag packetdiag pikchr plantuml rackdiag seqdiag structurizr
-                             svgbob symbolator tikz umlet vega vegalite wavedrom wireviz].freeze
-    HTTP_MAX_RETRIES = 3
-
-    class << self
-      # Renders and embeds all diagram descriptions in a Jekyll site using Kroki.
-      #
-      # @param [Jekyll::Site] The Jekyll site to embed diagrams in
-      def embed_site(site)
-        # Get the URL of the Kroki instance
-        kroki_url = kroki_url(site.config)
-        connection = setup_connection(kroki_url)
-
-        rendered_diag = 0
-        (site.pages + site.documents).each do |doc|
-          next unless embeddable?(doc)
-
-          # Render all supported diagram descriptions in the document
-          rendered_diag += embed_doc(connection, doc)
-        end
-
-        unless rendered_diag.zero?
-          puts "[jekyll-kroki] Rendered #{rendered_diag} diagrams using Kroki instance at '#{kroki_url}'"
-        end
-      rescue StandardError => e
-        exit(e)
-      end
-
-      # Renders all supported diagram descriptions in a document and embeds them as inline SVGs in the HTML source.
-      #
-      # @param [Faraday::Connection] The Faraday connection to use
-      # @param [Nokogiri::HTML4::Document] The parsed HTML document
-      # @param [Integer] The number of rendered diagrams
-      def embed_doc(connection, doc)
-        # Parse the HTML document
-        parsed_doc = Nokogiri::HTML(doc.output)
-        html_tags = %w[code div].freeze
-
-        rendered_diag = 0
+  # Converts diagram descriptions into images using Kroki
+  class Kroki
+    KROKI_DEFAULT_URL = "https://kroki.io"
+    SUPPORTED_LANGUAGES = %w[actdiag blockdiag bpmn bytefield c4plantuml d2 dbml diagramsnet ditaa erd excalidraw
+                             graphviz mermaid nomnoml nwdiag packetdiag pikchr plantuml rackdiag seqdiag structurizr
+                             svgbob symbolator tikz umlet vega vegalite wavedrom wireviz].freeze
+    EXPECTED_HTML_TAGS = %w[code div].freeze
+    HTTP_MAX_RETRIES = 3
+
+    class << self
+      # Renders and embeds all diagram descriptions in a Jekyll site using Kroki.
+      #
+      # @param [Jekyll::Site] The Jekyll site to embed diagrams in
+      def embed_site(site)
+        # Get the URL of the Kroki instance
+        kroki_url = kroki_url(site.config)
+        connection = setup_connection(kroki_url)
+
+        rendered_diag = 0
+        (site.pages + site.documents).each do |doc|
+          next unless embeddable?(doc)
+
+          # Render all supported diagram descriptions in the document
+          rendered_diag += embed_doc(connection, doc)
+        end
+
+        unless rendered_diag.zero?
+          puts "[jekyll-kroki] Rendered #{rendered_diag} diagrams using Kroki instance at '#{kroki_url}'"
+        end
+      rescue StandardError => e
+        exit(e)
+      end
+
+      # Renders all supported diagram descriptions in a document and embeds them as inline SVGs in the HTML source.
+      #
+      # @param [Faraday::Connection] The Faraday connection to use
+      # @param [Nokogiri::HTML4::Document] The parsed HTML document
+      # @param [Integer] The number of rendered diagrams
+      def embed_doc(connection, doc)
+        # Parse the HTML document
+        parsed_doc = Nokogiri::HTML(doc.output)
+
+        rendered_diag = 0
         SUPPORTED_LANGUAGES.each do |language|
-          html_tags.each do |tag|
+          EXPECTED_HTML_TAGS.each do |tag|
             parsed_doc.css("#{tag}[class~='language-#{language}']").each do |diagram_desc|
               # Replace the diagram description with the SVG representation rendered by Kroki
               diagram_desc.replace(render_diagram(connection, diagram_desc, language))
               rendered_diag += 1
             end
           end
-        end
-
-        end
-
-        # Convert the document back to HTML
-        doc.output = parsed_doc.to_html
-        rendered_diag
-      end
-
-      # Renders a single diagram description using Kroki.
-      #
-      # @param [Faraday::Connection] The Faraday connection to use
-      # @param [String] The diagram description
-      # @param [String] The language of the diagram description
-      # @return [String] The rendered diagram in SVG format
-      def render_diagram(connection, diagram_desc, language)
-        begin
-          response = connection.get("#{language}/svg/#{encode_diagram(diagram_desc.text)}")
-        rescue Faraday::Error => e
-          raise e.message
-        end
-        expected_content_type = "image/svg+xml"
-        returned_content_type = response.headers[:content_type]
-        if returned_content_type != expected_content_type
-          raise "Kroki returned an incorrect content type: " \
-                "expected '#{expected_content_type}', received '#{returned_content_type}'"
-
-        end
-        sanitise_diagram(response.body)
-      end
-
-      # Sanitises a rendered diagram. Only <script> elements are removed, which is the most minimal / naive
-      # implementation possible.
-      #
-      # @param [String] The diagram to santise in SVG format
-      # @return [String] The sanitised diagram
-      def sanitise_diagram(diagram_svg)
-        parsed_svg = Nokogiri::XML(diagram_svg)
-        parsed_svg.xpath('//*[name()="script"]').each(&:remove)
-        parsed_svg.to_xml
-      end
-
-      # Encodes the diagram into Kroki format using deflate + base64.
-      # See https://docs.kroki.io/kroki/setup/encode-diagram/.
-      #
-      # @param [String, #read] The diagram description to encode
-      # @return [String] The encoded diagram
-      def encode_diagram(diagram_desc)
-        Base64.urlsafe_encode64(Zlib.deflate(diagram_desc))
-      end
-
-      # Sets up a new Faraday connection.
-      #
-      # @param [URI::HTTP] The URL of the Kroki instance
-      # @return [Faraday::Connection] The Faraday connection
-      def setup_connection(kroki_url)
-        retry_options = { max: HTTP_MAX_RETRIES, interval: 0.1, interval_randomness: 0.5, backoff_factor: 2,
-                          exceptions: [Faraday::RequestTimeoutError, Faraday::ServerError] }
-
-        Faraday.new(url: kroki_url, request: { timeout: 5 }) do |builder|
-          builder.adapter :httpx, persistent: true
-          builder.request :retry, retry_options
-          builder.response :json, content_type: /\bjson$/
-          builder.response :raise_error
-        end
-      end
-
-      # Gets the URL of the Kroki instance to use for rendering diagrams.
-      #
-      # @param The Jekyll site configuration
-      # @return [URI::HTTP] The URL of the Kroki instance
-      def kroki_url(config)
-        if config.key?("kroki") && config["kroki"].key?("url")
-          url = config["kroki"]["url"]
-          raise TypeError, "'url' is not a valid HTTP URL" unless URI.parse(url).is_a?(URI::HTTP)
-
-          URI(url)
-        else
-          URI(KROKI_DEFAULT_URL)
-        end
-      end
-
-      # Determines whether a document may contain embeddable diagram descriptions - it is in HTML format and is either
-      # a Jekyll::Page or writeable Jekyll::Document.
-      #
-      # @param [Jekyll::Page or Jekyll::Document] The document to check for embedability
-      def embeddable?(doc)
-        doc.output_ext == ".html" && (doc.is_a?(Jekyll::Page) || doc.write?)
-      end
-
-      # Exits the Jekyll process without returning a stack trace. This method does not return because the process is
-      # abruptly terminated.
-      #
-      # @param [StandardError] The error to display in the termination message
-      # @param [int] The caller index to display in the termination message. The default index is 1, which means the
-      #              calling method. To specify the calling method's caller, pass in 2.
-      #
-      # Source: https://www.mslinn.com/ruby/2200-crash-exit.html
-      def exit(error, caller_index = 1)
-        raise error
-      rescue StandardError => e
-        file, line_number, caller = e.backtrace[caller_index].split(":")
-        caller = caller.tr("`", "'")
-        warn %([jekyll-kroki] "#{error.message}" #{caller} on line #{line_number} of #{file}).red
-        exec "exit 1"
-      end
-    end
-  end
+        end
+
+        # Convert the document back to HTML
+        doc.output = parsed_doc.to_html
+        rendered_diag
+      end
+
+      # Renders a single diagram description using Kroki.
+      #
+      # @param [Faraday::Connection] The Faraday connection to use
+      # @param [String] The diagram description
+      # @param [String] The language of the diagram description
+      # @return [String] The rendered diagram in SVG format
+      def render_diagram(connection, diagram_desc, language)
+        begin
+          response = connection.get("#{language}/svg/#{encode_diagram(diagram_desc.text)}")
+        rescue Faraday::Error => e
+          raise e.message
+        end
+        expected_content_type = "image/svg+xml"
+        returned_content_type = response.headers[:content_type]
+        if returned_content_type != expected_content_type
+          raise "Kroki returned an incorrect content type: " \
+                "expected '#{expected_content_type}', received '#{returned_content_type}'"
+
+        end
+        sanitise_diagram(response.body)
+      end
+
+      # Sanitises a rendered diagram. Only <script> elements are removed, which is the most minimal / naive
+      # implementation possible.
+      #
+      # @param [String] The diagram to santise in SVG format
+      # @return [String] The sanitised diagram
+      def sanitise_diagram(diagram_svg)
+        parsed_svg = Nokogiri::XML(diagram_svg)
+        parsed_svg.xpath('//*[name()="script"]').each(&:remove)
+        parsed_svg.to_xml
+      end
+
+      # Encodes the diagram into Kroki format using deflate + base64.
+      # See https://docs.kroki.io/kroki/setup/encode-diagram/.
+      #
+      # @param [String, #read] The diagram description to encode
+      # @return [String] The encoded diagram
+      def encode_diagram(diagram_desc)
+        Base64.urlsafe_encode64(Zlib.deflate(diagram_desc))
+      end
+
+      # Sets up a new Faraday connection.
+      #
+      # @param [URI::HTTP] The URL of the Kroki instance
+      # @return [Faraday::Connection] The Faraday connection
+      def setup_connection(kroki_url)
+        retry_options = { max: HTTP_MAX_RETRIES, interval: 0.1, interval_randomness: 0.5, backoff_factor: 2,
+                          exceptions: [Faraday::RequestTimeoutError, Faraday::ServerError] }
+
+        Faraday.new(url: kroki_url, request: { timeout: 5 }) do |builder|
+          builder.adapter :httpx, persistent: true
+          builder.request :retry, retry_options
+          builder.response :json, content_type: /\bjson$/
+          builder.response :raise_error
+        end
+      end
+
+      # Gets the URL of the Kroki instance to use for rendering diagrams.
+      #
+      # @param The Jekyll site configuration
+      # @return [URI::HTTP] The URL of the Kroki instance
+      def kroki_url(config)
+        if config.key?("kroki") && config["kroki"].key?("url")
+          url = config["kroki"]["url"]
+          raise TypeError, "'url' is not a valid HTTP URL" unless URI.parse(url).is_a?(URI::HTTP)
+
+          URI(url)
+        else
+          URI(KROKI_DEFAULT_URL)
+        end
+      end
+
+      # Determines whether a document may contain embeddable diagram descriptions - it is in HTML format and is either
+      # a Jekyll::Page or writeable Jekyll::Document.
+      #
+      # @param [Jekyll::Page or Jekyll::Document] The document to check for embedability
+      def embeddable?(doc)
+        doc.output_ext == ".html" && (doc.is_a?(Jekyll::Page) || doc.write?)
+      end
+
+      # Exits the Jekyll process without returning a stack trace. This method does not return because the process is
+      # abruptly terminated.
+      #
+      # @param [StandardError] The error to display in the termination message
+      # @param [int] The caller index to display in the termination message. The default index is 1, which means the
+      #              calling method. To specify the calling method's caller, pass in 2.
+      #
+      # Source: https://www.mslinn.com/ruby/2200-crash-exit.html
+      def exit(error, caller_index = 1)
+        raise error
+      rescue StandardError => e
+        file, line_number, caller = e.backtrace[caller_index].split(":")
+        caller = caller.tr("`", "'")
+        warn %([jekyll-kroki] "#{error.message}" #{caller} on line #{line_number} of #{file}).red
+        exec "exit 1"
+      end
+    end
+  end
 end
 
 Jekyll::Hooks.register :site, :post_render do |site|
-  Jekyll::Kroki.embed_site(site)
+  Jekyll::Kroki.embed_site(site)
 end