diff --git a/deploy.sh b/deploy.sh
index 264b455..71e67d2 100755
--- a/deploy.sh
+++ b/deploy.sh
@@ -1,49 +1,57 @@
 #!/usr/bin/env bash
 # ref: https://github.com/jekyll/jekyll
 
-set -eu
+set -eu  # Exit on error or unset variable
 
 PAGES_BRANCH="gh-pages"
 
 init() {
-  if [[ -z ${GITHUB_ACTION+x}]]; then
-    echo "ERROR: Not allowed to deploy outside of the GitHub Action envrionment."
-    exit -1
+  # Check if the script is running in a GitHub Actions environment
+  if [[ -z ${GITHUB_ACTION+x} ]]; then
+    echo "ERROR: Not allowed to deploy outside of the GitHub Action environment."
+    exit 1
   fi
 }
 
 build() {
+  # Run the Ruby script to generate the output
   bundle exec ruby "./scaffold.rb"
 
+  # Move all generated files to the root directory
   mv ./_output/* ./
 }
 
 setup_gh() {
+  # Delete the branch if it exists, and create a new one
   if git branch --list "$PAGES_BRANCH" > /dev/null; then
     echo "Branch '$PAGES_BRANCH' exists. Deleting and recreating it..."
-    git branch -D "$PAGES_BRANCH"  # Delete the branch
+    git branch -D "$PAGES_BRANCH"
   fi
 
-  # Create and switch to the branch
+  # Create and switch to the new branch
   git checkout -b "$PAGES_BRANCH"
 }
 
 deploy() {
+  # Configure Git user for the commit
   git config --global user.name "ZhgChgLiBot"
   git config --global user.email "no-reply@zhgchg.li"
 
+  # Reset the current HEAD to prepare for new commits
   git update-ref -d HEAD
   git add -A
   git commit -m "[Automation] Site update No.${GITHUB_RUN_NUMBER}"
 
-  git push -u origin "$PAGES_BRANCH"
+  # Push the new branch to the remote repository
+  git push -u origin "$PAGES_BRANCH" --force
 }
 
 main() {
-  init
-  build
-  setup_gh
-  deploy
+  init     # Initialize and validate environment
+  build    # Build the site
+  setup_gh # Set up the gh-pages branch
+  deploy   # Deploy the site
 }
 
-main
+# Execute the main function
+main
\ No newline at end of file