diff --git a/.env.example b/.env.example
index ce3f8e6..898c8fb 100644
--- a/.env.example
+++ b/.env.example
@@ -61,3 +61,11 @@ GITHUB_WEBHOOK_SECRET=your_github_webhook_secret
 # https://salem.opencoven.ai.
 # -----------------------------------------------------------------------------
 ALLOWED_ORIGINS=https://docs.opencoven.ai,https://opencoven.ai,https://salem.opencoven.ai
+
+# -----------------------------------------------------------------------------
+# PUBLIC BASE URL (optional)
+# Absolute origin of this deployment, used only to build Open Graph / Twitter
+# card image URLs in the page metadata. Not used by the chat API itself.
+# Defaults to https://salem.opencoven.ai.
+# -----------------------------------------------------------------------------
+NEXT_PUBLIC_BASE_URL=https://salem.opencoven.ai