Merge pull request 'Fix bug with heading styles' (#4) from bug/heading-styles into main

Reviewed-on: Kaukus/ezdoc#4

lib/ezdoc/document.rb

@@ -67,13 +67,13 @@ module Ezdoc
     end
 
     def register_built_in_styles
-      # Headings
-      define_style :heading1, size: 24, bold: true
-      define_style :heading2, size: 18, bold: true
-      define_style :heading3, size: 14, bold: true
-      define_style :heading4, size: 12, bold: true
-      define_style :heading5, size: 11, bold: true, italic: true
-      define_style :heading6, size: 10, bold: true, italic: true
+      # Headings (spacing_before ensures they're rendered as paragraph styles)
+      define_style :heading1, size: 24, bold: true, spacing_before: 240, spacing_after: 120
+      define_style :heading2, size: 18, bold: true, spacing_before: 200, spacing_after: 100
+      define_style :heading3, size: 14, bold: true, spacing_before: 160, spacing_after: 80
+      define_style :heading4, size: 12, bold: true, spacing_before: 120, spacing_after: 60
+      define_style :heading5, size: 11, bold: true, italic: true, spacing_before: 100, spacing_after: 40
+      define_style :heading6, size: 10, bold: true, italic: true, spacing_before: 80, spacing_after: 40
 
       # Other built-in styles
       define_style :title, size: 26, bold: true, align: :center