update theme

themes/blowfish/config/_default/markup.toml

@@ -2,8 +2,15 @@
 # These settings are required for the theme to function.
 
 [goldmark]
-[goldmark.renderer]
-  unsafe = true
+  [goldmark.renderer]
+    unsafe = true
+
+  [goldmark.extensions]
+    [goldmark.extensions.passthrough]
+      enable = true
+      [goldmark.extensions.passthrough.delimiters]
+        block = [['\[', '\]'], ['$$', '$$']]
+        inline = [['\(', '\)']]
 
 [highlight]
   noClasses = false