diff --git a/docs/iris.sty b/docs/iris.sty
index 414a1b0e9e73786a1198a4fa89508b99fbe5502f..906546626954f4ee88ebc300dc40c2a5f047ef6c 100644
--- a/docs/iris.sty
+++ b/docs/iris.sty
@@ -10,7 +10,6 @@
 \RequirePackage{xstring}
 \RequirePackage{mathtools}
 
-
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% SETUP
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -166,8 +165,9 @@
 
 \newcommand{\munit}{\varepsilon}
 \newcommand{\mcore}[1]{{\mid}#1{\mid}} % using "|" here makes LaTeX diverge. WTF.
-\newcommand{\mnocore}\top
+\newcommand{\mnocore}{\bot}
 \newcommand{\mtimes}{\mathbin{\cdot}}
+\newcommand{\mundefined}{\lightning}
 
 \newcommand{\mupd}{\rightsquigarrow}
 \newcommand{\mincl}[1][]{\ensuremath{\mathrel{\stackrel{#1}{\preccurlyeq}}}}
@@ -391,7 +391,7 @@
 \newcommand{\Auth}{\textsf{Auth}}
 
 % Sum
-\newcommand{\csumm}{\mathrel{+_{\!\bot}}}
+\newcommand{\csumm}{\mathrel{+_{\!\mundefined}}}
 \newcommand{\cinl}{\textsf{inl}}
 \newcommand{\cinr}{\textsf{inr}}