diff --git a/lib/jekyll-pdf.rb b/lib/jekyll-pdf.rb
index 6bb8bd2..15eff39 100644
--- a/lib/jekyll-pdf.rb
+++ b/lib/jekyll-pdf.rb
@@ -1 +1 @@
-require "jekyll/pdf"
\ No newline at end of file
+require 'jekyll/pdf'
diff --git a/lib/jekyll/pdf.rb b/lib/jekyll/pdf.rb
index 3804904..c17694b 100644
--- a/lib/jekyll/pdf.rb
+++ b/lib/jekyll/pdf.rb
@@ -1 +1 @@
-Dir[File.dirname(__FILE__) + '/pdf/**/*.rb'].each {|file| require file }
\ No newline at end of file
+Dir[File.dirname(__FILE__) + '/pdf/**/*.rb'].each { |file| require file }
diff --git a/lib/jekyll/pdf/document.rb b/lib/jekyll/pdf/document.rb
index 0b2ae72..edee2b7 100644
--- a/lib/jekyll/pdf/document.rb
+++ b/lib/jekyll/pdf/document.rb
@@ -12,55 +12,60 @@ module Jekyll
         @dir = File.dirname(page.url)
         @name = File.basename(page.url, File.extname(page.url)) + '.pdf'
         @settings = site.config.key?('pdf') ? site.config['pdf'].clone : {}
-        @partials = ['cover','header_html','footer_html']
+        @partials = %w[cover header_html footer_html]
 
-        self.process(@name)
+        process(@name)
         self.data = page.data.clone
         self.content = page.content.clone
 
         # Set layout to the PDF layout
-        self.data['layout'] = layout
+        data['layout'] = layout
 
         # Get PDF settings from the layouts
-        Jekyll::Utils.deep_merge_hashes!(@settings, self.getConfig(self.data))
+        Jekyll::Utils.deep_merge_hashes!(@settings, getConfig(data))
 
         PDFKit.configure do |config|
           config.verbose = site.config['verbose']
         end
 
         # Set pdf_url variable in the source page (for linking to the PDF version)
-        page.data['pdf_url'] = self.url
+        page.data['pdf_url'] = url
 
         # Set html_url variable in the source page (for linking to the HTML version)
-        self.data['html_url'] = page.url
+        data['html_url'] = page.url
 
         # create the partial objects
         @partials.each do |partial|
-          @settings[partial] = Jekyll::PDF::Partial.new(self, @settings[partial]) if @settings[partial] != nil
+          @settings[partial] = Jekyll::PDF::Partial.new(self, @settings[partial]) unless @settings[partial].nil?
         end
+
+        data.default_proc = proc do |_, key|
+          site.frontmatter_defaults.find(File.join(dir, name), type, key)
+        end
+        Jekyll::Hooks.trigger :pages, :post_init, self
       end
 
       # Recursively merge settings from the page, layout, site config & jekyll-pdf defaults
       def getConfig(data)
         settings = data['pdf'].is_a?(Hash) ? data['pdf'] : {}
-        layout = @site.layouts[data['layout']].data.clone if data['layout'] != nil
+        layout = @site.layouts[data['layout']].data.clone unless data['layout'].nil?
 
         # No parent layout found - return settings hash
-        return settings if layout == nil
+        return settings if layout.nil?
 
         # Merge settings with parent layout settings
         layout['pdf'] ||= {}
         Jekyll::Utils.deep_merge_hashes!(layout['pdf'], settings)
 
-        return self.getConfig(layout)
+        getConfig(layout)
       end
 
       # Write the PDF file
       # todo: remove pdfkit dependency
-      def write(dest_prefix, dest_suffix = nil)
-        self.render(@site.layouts, @site.site_payload) if self.output == nil
+      def write(dest_prefix, _dest_suffix = nil)
+        render(@site.layouts, @site.site_payload) if output.nil?
 
-        path = File.join(dest_prefix, CGI.unescape(self.url))
+        path = File.join(dest_prefix, CGI.unescape(url))
         dest = File.dirname(path)
 
         # Create directory
@@ -68,32 +73,31 @@ module Jekyll
 
         # write partials
         @partials.each do |partial|
-          @settings[partial].write if @settings[partial] != nil
+          @settings[partial].write unless @settings[partial].nil?
         end
 
         # Debugging - create html version of PDF
-        File.open("#{path}.html", 'w') {|f| f.write(self.output) } if @settings["debug"]
-        @settings.delete("debug")
+        File.open("#{path}.html", 'w') { |f| f.write(output) } if @settings['debug']
+        @settings.delete('debug')
+        @settings.delete('layout')
 
         # Build PDF file
         fix_relative_paths
-        kit = PDFKit.new(self.output, @settings)
+        kit = PDFKit.new(output, @settings)
         file = kit.to_file(path)
       end
 
-      def layout()
+      def layout
         # Set page layout to the PDF layout
-        layout = self.data['pdf_layout'] || @settings['layout']
+        layout = data['pdf_layout'] || @settings['layout']
 
         # Check if a PDF version exists for the current layout (e.g. layout_pdf)
-        if layout == nil && self.data['layout'] != nil && File.exist?("_layouts/" + self.data['layout'] + "_pdf.html")
-          layout = self.data['layout'] + "_pdf"
+        if layout.nil? && !data['layout'].nil? && File.exist?('_layouts/' + data['layout'] + '_pdf.html')
+          layout = data['layout'] + '_pdf'
         end
 
         layout || 'pdf'
       end
-
     end
-
   end
 end
diff --git a/lib/jekyll/pdf/generator.rb b/lib/jekyll/pdf/generator.rb
index 2acc3ae..874fa7c 100644
--- a/lib/jekyll/pdf/generator.rb
+++ b/lib/jekyll/pdf/generator.rb
@@ -5,14 +5,10 @@ module Jekyll
       priority :lowest
 
       def generate(site)
-        # Loop through pages & documents and build PDFs
-        [site.pages.clone, site.documents].each do |items|
-          items.each do |item|
-            site.pages << Document.new(site, site.source, item) if item.data['pdf']
-          end
+        [site.pages.clone, site.documents].flatten.each do |item|
+          site.pages << Document.new(site, site.source, item) if item.data['pdf']
         end
       end
-
     end
   end
 end
diff --git a/lib/jekyll/pdf/helper.rb b/lib/jekyll/pdf/helper.rb
index cf12808..46bb3ea 100644
--- a/lib/jekyll/pdf/helper.rb
+++ b/lib/jekyll/pdf/helper.rb
@@ -2,7 +2,7 @@ module Jekyll
   module PDF
     module Helper
       def fix_relative_paths
-        output.gsub!(/(href|src)=(['"])\/([^\/"']([^\"']*|[^"']*))?['"]/, "\\1=\\2file://#{site.dest}/\\3\\2") if output != nil
+        output.gsub!(/(href|src)=(['"])\/([^\/"']([^\"']*|[^"']*))?['"]/, "\\1=\\2file://#{site.dest}/\\3\\2") unless output.nil?
       end
     end
   end
diff --git a/lib/jekyll/pdf/hooks.rb b/lib/jekyll/pdf/hooks.rb
index a9ca945..3105cec 100644
--- a/lib/jekyll/pdf/hooks.rb
+++ b/lib/jekyll/pdf/hooks.rb
@@ -1,9 +1,9 @@
 # Delete temp files
-Jekyll::Hooks.register :site, :post_write do |jekyll, payload|
+Jekyll::Hooks.register :site, :post_write do |jekyll, _payload|
   if jekyll.data[:jekyll_pdf_partials]
     jekyll.data[:jekyll_pdf_partials].each do |partial|
       File.delete(partial) if File.exist?(partial)
     end
     jekyll.data.delete(:jekyll_pdf_partials)
   end
-end
\ No newline at end of file
+end
diff --git a/lib/jekyll/pdf/partial.rb b/lib/jekyll/pdf/partial.rb
index 0f0f1ee..fa9dc02 100644
--- a/lib/jekyll/pdf/partial.rb
+++ b/lib/jekyll/pdf/partial.rb
@@ -15,7 +15,7 @@ module Jekyll
       attr_writer   :output
 
       def_delegators :@doc, :site, :name, :ext, :relative_path, :extname,
-                            :render_with_liquid?, :collection, :related_posts
+                     :render_with_liquid?, :collection, :related_posts
 
       # Initialize this Partial instance.
       #
@@ -33,19 +33,18 @@ module Jekyll
       # Returns Hash of doc data
       def data
         @data ||= doc.data.dup
-        @data.delete("layout")
+        @data.delete('layout')
         @data
       end
 
-      def trigger_hooks(*)
-      end
+      def trigger_hooks(*); end
 
       def path
         File.join(doc.path, partial)
       end
 
       def id
-        File.basename(path, File.extname(path)) + "-" + Digest::MD5.hexdigest(to_s) + File.extname(path)
+        File.basename(path, File.extname(path)) + '-' + Digest::MD5.hexdigest(to_s) + File.extname(path)
       end
 
       # Returns the cache directory
@@ -66,7 +65,7 @@ module Jekyll
 
       # Returns the shorthand String identifier of this doc.
       def inspect
-        "<Partial: #{self.id}>"
+        "<Partial: #{id}>"
       end
 
       def output
@@ -79,13 +78,13 @@ module Jekyll
         unless File.exist?(tempfile)
           FileUtils.mkdir_p(File.dirname(tempfile)) unless File.exist?(File.dirname(tempfile))
           fix_relative_paths
-          File.open(tempfile, 'w') {|f| f.write(to_s) }
+          File.open(tempfile, 'w') { |f| f.write(to_s) }
         end
         @output = tempfile
 
         # store path for cleanup
         site.data[:jekyll_pdf_partials] ||= []
-        site.data[:jekyll_pdf_partials] << "#{self}"
+        site.data[:jekyll_pdf_partials] << to_s
       end
 
       def place_in_layout?
@@ -95,12 +94,12 @@ module Jekyll
       protected
 
       def cache_dir
-        return site.config["pdf"]["cache"] if site.config["pdf"] != nil && site.config["pdf"].has_key?('cache')
+        return site.config['pdf']['cache'] if !site.config['pdf'].nil? && site.config['pdf'].key?('cache')
 
         # Use jekyll-assets cache directory if it exists
-        cache_dir = site.config["assets"]["cache"] || '.asset-cache' if site.config["assets"] != nil
+        cache_dir = site.config['assets']['cache'] || '.asset-cache' unless site.config['assets'].nil?
 
-        File.join(cache_dir || Dir.tmpdir(), 'pdf')
+        File.join(cache_dir || Dir.tmpdir, 'pdf')
       end
 
       # Internal: Generate partial html
@@ -109,23 +108,22 @@ module Jekyll
       #
       # Returns partial html String
       def build_partial(path)
-
         # vars to insert into partial
-        vars = ['frompage','topage','page','webpage','section','subsection','subsubsection']
-        doc.data["pdf"] = {}
-        vars.each { |var| doc.data["pdf"][var] = "<span class='__#{var}'></span>" }
+        vars = %w[frompage topage page webpage section subsection subsubsection]
+        doc.data['pdf'] = {}
+        vars.each { |var| doc.data['pdf'][var] = "<span class='__#{var}'></span>" }
 
         # JavaScript to replace var placeholders with content
         script = "<script>!function(){var t={},n=document.location.search.substring(1).split('&');for(var e in n){var o=n[e].split('=',2);t[o[0]]=decodeURIComponent(o[1])}var n=#{vars};for(var e in n)for(var r=document.getElementsByClassName('__'+n[e]),a=0;a<r.length;++a)r[a].textContent=t[n[e]]}();</script>\n"
 
         # Parse & render
-        content = File.read(File.join("_includes", path))
+        content = File.read(File.join('_includes', path))
 
         # Add replacer script to body
         if content =~ /<\/body>/i
           content[/(<\/body>)/i] = script + content[/(<\/body>)/i]
         else
-          Jekyll.logger.warn  <<-eos
+          Jekyll.logger.warn <<-eos
   Couldn't find <body> in #{path}. Make sure your partial is a properly formatted HTML document (including DOCTYPE) e.g.
 
   <!DOCTYPE html>
@@ -139,19 +137,18 @@ module Jekyll
   </html>
   eos
           # No body found - insert html into default template
-          content = %{<!DOCTYPE html>
+          content = %(<!DOCTYPE html>
   <html>
     <body>
-    #{self.output}
+    #{output}
     #{script}
     </body>
   </html>
-  }
+  )
         end
 
         content
-
       end
     end
   end
-end
\ No newline at end of file
+end