Set node_env to production in Dockerfile

Dockerfile

@@ -8,12 +8,12 @@ WORKDIR /app
 COPY package.json package-lock.json ./
 COPY ./app/templates ./app/templates
 COPY tailwind.config.js ./
-COPY ./app/static/css/tailwind.css ./app/static/css/tailwind.css
 
 # Install Node.js dependencies
 RUN npm install
 
-# Build TailwindCSS assets
+# Set NODE_ENV to production and build TailwindCSS assets
+ENV NODE_ENV=production
 RUN npm run build
 
 # Stage 2: Python for Flask app