Make sure we access keys via strings and not symbols

config.rb

@@ -98,10 +98,10 @@ end
 
 helpers do
   def themes
-    data.themes.sort_by { |theme| theme[:name] }.map do |theme|
+    data.themes.sort_by { |theme| theme['name'] }.map do |theme|
         OpenStruct.new(theme.merge(
-            slug: theme[:name].parameterize.underscore,
+            slug: theme['name'].parameterize.underscore,
-            digest: Digest::MD5.new.hexdigest(theme[:colors])
+            digest: Digest::MD5.new.hexdigest(theme['colors'])
         ))
     end
   end