diff --git a/docs/ain48.sublime-syntax b/docs/ain48.sublime-syntax
index 6fcab7f..06527bc 100644
--- a/docs/ain48.sublime-syntax
+++ b/docs/ain48.sublime-syntax
@@ -10,7 +10,7 @@ contexts:
       scope: keyword.operator.word.ain48
     - match: '(?i)%([a-z0-7]+)\b'
       scope: variable.register.ain48
-    - match: '#-?([0-5]+|o[0-7]+|b[01]+|x[0-9]+)\b'
+    - match: '#-?(s[0-5]+|o[0-7]+|b[01]+|x[0-9]+)\b'
       scope: constant.numeric.ain48
     - match: '#imm\[[0-9n]+\]'
       scope: constant.numeric.ain48