add docker setup

.dockerignore

@@ -0,0 +1,5 @@
+.git
+.gitignore
+.dockerignore
+_site/
+.bundle/README.md   

Dockerfile

@@ -0,0 +1,40 @@
+# Stage 1: The Builder Environment
+FROM ruby:3.2.2 AS builder
+
+# Set the working directory inside the container
+WORKDIR /usr/src/app
+
+# Install dependencies required to build the site
+# Try Alpine's apk first; fall back to Debian's apt-get if apk isn't available.
+RUN set -eux; \
+	if command -v apk >/dev/null 2>&1; then \
+		apk add --no-cache build-base; \
+	elif command -v apt-get >/dev/null 2>&1; then \
+		apt-get update && apt-get install -y build-essential; \
+	else \
+		echo 'No supported package manager found (apk or apt-get)'; exit 1; \
+	fi
+
+# Copy the Gemfile and Gemfile.lock to leverage Docker's layer caching
+COPY Gemfile Gemfile.lock ./
+
+# Install the Ruby gems
+RUN bundle install
+
+# Copy the rest of the application source code
+COPY . .
+
+# Build the Jekyll site. The output will be in the /usr/src/app/_site directory.
+RUN bundle exec jekyll build
+
+# ---
+
+# Stage 2: The Production Environment
+# We use a lightweight Nginx image to serve the static files.
+FROM nginx:alpine
+
+# Copy the built static site from the 'builder' stage
+COPY --from=builder /usr/src/app/_site /usr/share/nginx/html
+
+# Expose port 80 to allow traffic to the web server
+EXPOSE 80

Gemfile

@@ -1,2 +1,5 @@
 source 'https://rubygems.org'
-gem 'github-pages'
+
+gem 'github-pages', '~> 232'
+
+ruby '3.2.2'

Gemfile.lock

@@ -2,9 +2,8 @@ GEM
   remote: https://rubygems.org/
   specs:
     RedCloth (4.2.9)
-    activesupport (4.2.6)
+    activesupport (4.2.11.3)
       i18n (~> 0.7)
-      json (~> 1.7, >= 1.7.7)
       minitest (~> 5.1)
       thread_safe (~> 0.3, >= 0.3.4)
       tzinfo (~> 1.1)
@@ -89,7 +88,6 @@ GEM
       gemoji (~> 2.0)
       html-pipeline (~> 2.2)
       jekyll (>= 2.0)
-    json (1.8.3)
     kramdown (1.10.0)
     liquid (3.0.6)
     listen (3.0.6)
@@ -132,4 +130,4 @@ DEPENDENCIES
   github-pages
 
 BUNDLED WITH
-   1.11.2
+   2.7.2