diff --git a/.github/workflows/push-main.yaml b/.github/workflows/push-main.yaml
index e7ea93ad..c331acc8 100644
--- a/.github/workflows/push-main.yaml
+++ b/.github/workflows/push-main.yaml
@@ -49,10 +49,11 @@ jobs:
 
       - name: run buildWebpage
         id: run-buildWebpage
+        env:
+          GITHUB_PAGES_BASEURL: https://dwrensha.github.io/math-puzzles-in-lean4/
         run: |
           set -o pipefail
           echo "Starting build at $(date +'%T')"
-          export GITHUB_PAGES_BASEURL="https://dwrensha.github.io/math-puzzles-in-lean4/"
           build/bin/buildWebpage
           result_run1=$?
           echo "Complete at $(date +'%T'); return value $result_run1"