diff --git a/blog/convert.rb b/blog/convert.rb
index 8d5232b..36e6655 100644
--- a/blog/convert.rb
+++ b/blog/convert.rb
@@ -29,7 +29,7 @@ inline_cache, display_cache = {}, {}
 files.each do |file|
   puts "Rendering file: #{file}"
   document = Nokogiri::HTML.parse(File.open(file))
-  document.search('//*[not(self::code)]/text()').each do |t|
+  document.search('//*[not(ancestor-or-self::code)]/text()').each do |t|
     t.replace(perform_katex_sub(inline_cache, display_cache, t.content))
   end
   File.write(file, document.to_html)