diff --git a/.gitea/workflows/update-docs.yml b/.gitea/workflows/update-docs.yml
index 82ec486..296baf0 100644
--- a/.gitea/workflows/update-docs.yml
+++ b/.gitea/workflows/update-docs.yml
@@ -5,7 +5,7 @@ on:
       - 'docs/**'
 jobs:
   build_docs:
-    runs_on: ubuntu-latest
+    runs-on: ubuntu-latest
     steps:
       - name: Set up Git repository
         uses: actions/checkout@v6
diff --git a/docs/docs.pdf b/docs/docs.pdf
index ddc0aa7..351497b 100644
Binary files a/docs/docs.pdf and b/docs/docs.pdf differ
diff --git a/src/core/math.sty b/src/core/math.sty
index 0ac1e3d..5f257b6 100644
--- a/src/core/math.sty
+++ b/src/core/math.sty
@@ -88,7 +88,6 @@
 \newcommand{\limsupni}{\limsup_{n \rightarrow \infty}}
 \newcommand{\sequence}[1]{(#1_n)_{n \geq 1}}
 \newcommand{\series}[2]{\sum_{k = 1}^{#2} #1_k}
-\newcommand{\elementstack}[2]{\genfrac{}{}{0pt}{}{#1}{#2}}
 
 \DeclareMathOperator\arctanh{arctanh}
 \DeclareMathOperator\arccosh{arccosh}