diff --git a/.gitignore b/.gitignore
index 84a7f19..dca28e4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 doc/html
 .DS_Store
+doc/antora_specimen/build
diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..4ac83c2
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "doc/antora_specimen/content"]
+	path = doc/antora_specimen/content
+	url = https://github.com/julioest/antora-specimen.git
diff --git a/DEVELOPMENT.md b/DEVELOPMENT.md
new file mode 100644
index 0000000..150cfd0
--- /dev/null
+++ b/DEVELOPMENT.md
@@ -0,0 +1,321 @@
+# BoostLook CSS Development Guide
+
+This guide covers the workflow for developers working on `boostlook.css` and its integration with Boost documentation systems.
+
+## Table of Contents
+
+- [Overview](#overview)
+- [Development Environment Setup](#development-environment-setup)
+- [CSS Development Workflows](#css-development-workflows)
+  - [AsciiDoc Workflow](#asciidoc-workflow)
+  - [Antora Workflow](#antora-workflow)
+- [File Structure](#file-structure)
+- [CSS Architecture](#css-architecture)
+- [Testing Your Changes](#testing-your-changes)
+- [Integration Guidelines](#integration-guidelines)
+- [Troubleshooting](#troubleshooting)
+
+## Overview
+
+BoostLook provides a unified styling system for Boost documentation that works with both:
+
+1. **AsciiDoc** - Traditional single-document rendering via Asciidoctor
+2. **Antora** - Multi-component documentation sites
+
+The main stylesheet `boostlook.css` is designed to work across both systems while maintaining visual consistency.
+
+## Development Environment Setup
+
+### Prerequisites
+
+- **Ruby** (>= 2.7)
+- **Node.js** (for Antora)
+- **Required Ruby Gems**:
+  ```bash
+  gem install asciidoctor listen
+  ```
+- **Required Node Packages**:
+  ```bash
+  npm install -g @antora/cli @antora/site-generator
+  ```
+- **Boost.Build (b2)** - Available in PATH
+
+### Project Structure
+
+```
+boostlook/
+├── boostlook.css               # Main stylesheet
+├── boostlook.rb                # Asciidoctor extension
+├── boostlook_preview.rb        # AsciiDoc live preview
+├── boostlook_antora_preview.rb # Antora live preview
+├── doc/
+│   ├── specimen.adoc           # Test AsciiDoc document
+│   ├── specimen-docinfo-footer.html
+│   ├── Jamfile                 # Boost.Build configuration
+│   ├── html/                   # AsciiDoc build output
+│   └── antora_specimen/        # Antora test site
+│       ├── playbook.yml
+│       ├── content/
+│       └── build/
+└── fonts/                      # Noto font files
+```
+
+## CSS Development Workflows
+
+### AsciiDoc Workflow
+
+Use this workflow when developing styles for traditional AsciiDoc documentation.
+
+#### 1. Start Live Preview
+
+```bash
+cd /path/to/boostlook
+ruby boostlook_preview.rb
+```
+
+This will:
+- Build `doc/specimen.adoc` using Boost.Build
+- Open the result in your browser
+- Watch for changes to `boostlook.css` and auto-rebuild
+
+#### 2. Edit CSS
+
+- Edit `boostlook.css` in your preferred editor
+- Changes are automatically detected and trigger a rebuild
+- Refresh your browser to see updates
+
+#### 3. Test Content
+
+- Edit `doc/specimen.adoc` to test different AsciiDoc elements
+- The specimen document includes examples of:
+  - Headers and sections
+  - Code blocks
+  - Tables
+  - Lists and admonitions
+  - Cross-references
+
+#### Monitored Files
+
+The preview script watches these files for changes:
+- `boostlook.css`
+- `boostlook.rb`
+- `doc/specimen.adoc`
+- `doc/specimen-docinfo-footer.html`
+- `doc/Jamfile`
+
+### Antora Workflow
+
+Use this workflow when developing styles for Antora-based documentation sites.
+
+#### 1. Start Antora Preview
+
+```bash
+cd /path/to/boostlook
+ruby boostlook_antora_preview.rb
+```
+
+This will:
+- Build the Antora specimen site (if not already built)
+- Copy `boostlook.css` to the build directory
+- Open the site in your browser
+- Watch for CSS changes and auto-update
+
+#### 2. Edit CSS
+
+- Edit `boostlook.css` in your preferred editor
+- Changes are automatically copied to the Antora build
+- Refresh your browser to see updates
+
+#### 3. Test with Real Content
+
+The Antora specimen includes:
+- **Boost.URL** documentation (complete structure)
+- **Specimen component** (test content)
+- Navigation between components
+- Real-world documentation patterns
+
+#### Features
+
+- **Fast Updates**: Only CSS is copied on changes (no full rebuild)
+- **Hash Checking**: Prevents unnecessary updates
+- **Multi-component**: Test navigation and component switching
+
+## File Structure
+
+### Core Files
+
+| File | Purpose |
+|------|---------|
+| `boostlook.css` | Main stylesheet (161KB, 4300+ lines) |
+| `boostlook.rb` | Asciidoctor extension and integration |
+| `boostlook_preview.rb` | AsciiDoc development server |
+| `boostlook_antora_preview.rb` | Antora development server |
+
+### Test Documents
+
+| Path | Purpose |
+|------|---------|
+| `doc/specimen.adoc` | AsciiDoc test document |
+| `doc/antora_specimen/` | Complete Antora test site |
+| `doc/antora_specimen/content/url_component/` | Real Boost.URL docs |
+
+## CSS Architecture
+
+### Key Sections
+
+1. **Base Styles** - Typography, colors, layout fundamentals
+2. **AsciiDoc Elements** - Styling for `.sect1`, `.listingblock`, etc.
+3. **Antora Components** - Navigation, TOC, component switching
+4. **Code Highlighting** - Syntax highlighting styles
+5. **Responsive Design** - Mobile and tablet adaptations
+
+### CSS Classes
+
+#### AsciiDoc-specific
+- `.sect1`, `.sect2`, etc. - Section headers
+- `.listingblock` - Code blocks
+- `.admonitionblock` - Warnings, notes, tips
+- `.tableblock` - Tables
+
+#### Antora-specific
+- `.nav-container` - Main navigation
+- `.article` - Main content area
+- `.toc` - Table of contents
+- `.toolbar` - Header toolbar
+
+### Font Integration
+
+The stylesheet includes references to Noto fonts:
+- `NotoSansDisplay.ttf` - Display text
+- `NotoSansMono.ttf` - Monospace code
+- Font files are loaded via `@font-face` declarations
+
+## Testing Your Changes
+
+### Browser Testing
+
+Test your changes across:
+- **Chrome/Chromium** - Primary development browser
+- **Firefox** - Secondary testing
+- **Safari** (macOS) - WebKit compatibility
+- **Mobile browsers** - Responsive design
+
+### Content Testing
+
+#### For AsciiDoc
+- Headers (h1-h6)
+- Code blocks with syntax highlighting
+- Tables with various column types
+- Lists (ordered, unordered, definition)
+- Admonitions (NOTE, TIP, WARNING, etc.)
+- Cross-references and links
+
+#### For Antora
+- Component navigation
+- Multi-level page hierarchy
+- Search functionality
+- Mobile navigation
+- Component switching
+
+### Performance Considerations
+
+- **CSS Size**: Current file is 161KB - consider impact of additions
+- **Font Loading**: Ensure fonts load efficiently
+- **Mobile Performance**: Test on slower devices
+
+## Integration Guidelines
+
+### Adding New Styles
+
+1. **Follow existing patterns**: Study current CSS organization
+2. **Use semantic naming**: `.boost-` prefix for custom classes
+3. **Mobile-first**: Add responsive styles appropriately
+4. **Test both systems**: Verify in both AsciiDoc and Antora
+
+### Modifying Existing Styles
+
+1. **Test thoroughly**: Changes affect existing documentation
+2. **Check specificity**: Avoid overly specific selectors
+3. **Maintain consistency**: Keep visual harmony across components
+
+### Version Control
+
+- Commit CSS changes with descriptive messages
+- Include screenshots for visual changes
+- Test builds before pushing
+
+## Troubleshooting
+
+### Common Issues
+
+#### Preview Script Not Starting
+```bash
+# Check Ruby installation
+ruby -v
+
+# Install missing gems
+gem install asciidoctor listen
+
+# Check Boost.Build
+which b2
+```
+
+#### Antora Build Fails
+```bash
+# Check Node.js and Antora
+node -v
+npx antora --version
+
+# Clear build and retry
+rm -rf doc/antora_specimen/build
+ruby boostlook_antora_preview.rb
+```
+
+#### CSS Changes Not Appearing
+
+1. **Clear browser cache**: Hard refresh (Ctrl+F5 / Cmd+Shift+R)
+2. **Check file permissions**: Ensure CSS files are writable
+3. **Verify file paths**: Check console for 404 errors
+4. **Restart preview script**: Stop and restart the Ruby script
+
+#### Font Loading Issues
+
+- Verify font files are present in project root
+- Check browser dev tools for font loading errors
+- Ensure CORS headers allow font loading (for file:// URLs)
+
+### Debug Mode
+
+Both preview scripts support verbose logging:
+```bash
+# Add debug logging
+RUBY_DEBUG=1 ruby boostlook_preview.rb
+```
+
+### Manual Builds
+
+If preview scripts fail, you can build manually:
+
+**AsciiDoc:**
+```bash
+cd doc
+b2
+```
+
+**Antora:**
+```bash
+cd doc/antora_specimen
+npx antora playbook.yml
+```
+
+## Tips for Efficient Development
+
+1. **Use browser dev tools**: Inspect elements and test CSS changes live
+2. **Keep both previews running**: Test AsciiDoc and Antora simultaneously
+3. **Use CSS custom properties**: For consistent colors and measurements
+4. **Comment your changes**: Help future developers understand your choices
+5. **Test edge cases**: Very long titles, nested lists, complex tables
+
+---
+
+For questions or issues, refer to the main [README.md](README.md) or check the project's issue tracker.
diff --git a/README.md b/README.md
index f860e92..ea80ffc 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,13 @@ This is a set of stylesheets, templates, and code for Asciidoctor and
 Antora rendered documentation to give it a uniform look and feel
 befitting the quality of Boost.
 
+## Documentation
+
+- **[DEVELOPMENT.md](DEVELOPMENT.md)** - Complete guide for developers working on `boostlook.css`
+- **[Live Preview Setup](#live-preview-for-asciidoc-documentation)** - Quick start for AsciiDoc preview
+
+## Integration
+
 Example of integration into a doc Jamfile:
 ```
 html mp11.html : mp11.adoc
diff --git a/boostlook_antora_preview.rb b/boostlook_antora_preview.rb
new file mode 100755
index 0000000..7fe8847
--- /dev/null
+++ b/boostlook_antora_preview.rb
@@ -0,0 +1,240 @@
+#!/usr/bin/env ruby
+
+require 'listen'
+require 'fileutils'
+require 'logger'
+require 'pathname'
+require 'open3'
+require 'digest/md5'
+
+# BoostlookAntoraPreview handles building the Antora specimen site and monitoring CSS changes
+class BoostlookAntoraPreview
+  # Define relevant paths
+  PATHS = {
+    source_css: 'boostlook.css',
+    antora_dir: 'doc/antora_specimen',
+    build_dir: 'doc/antora_specimen/build/site',
+    build_css: 'doc/antora_specimen/build/site/_/css/boostlook.css',
+    playbook: 'doc/antora_specimen/playbook.yml',
+    ui_bundle: 'doc/antora_specimen/ui/ui-bundle.zip'
+  }.freeze
+
+  # OS-specific commands to open the default web browser
+  OS_BROWSER_COMMANDS = {
+    /darwin/       => 'open',       # macOS
+    /linux/        => 'xdg-open',   # Linux
+    /mingw|mswin/  => 'start'       # Windows
+  }.freeze
+
+  def initialize
+    # Initialize the logger
+    @logger = Logger.new($stdout)
+    @logger.level = Logger::INFO
+    @logger.formatter = ->(_, _, _, msg) { "#{msg}\n" }
+
+    @file_opened = false          # Flag to prevent multiple browser openings
+    @shutdown_requested = false   # Flag to handle graceful shutdown
+    @antora_version = nil         # Will store the detected Antora version
+    @last_css_hash = nil          # Store the last CSS file hash to avoid loops
+    @processing_change = false    # Flag to prevent recursive change detection
+  end
+
+  # Entry point to run the preview
+  def run
+    check_dependencies
+    ensure_site_built
+    setup_signal_traps
+    watch_files
+  end
+
+  private
+
+  # Check if Antora is installed and get its version
+  def check_dependencies
+    stdout, status = Open3.capture2('npx antora --version 2>/dev/null')
+
+    unless status.success?
+      @logger.error("'npx antora' command failed. Please install Antora: npm i @antora/cli @antora/site-generator")
+      exit 1
+    end
+
+    # Extract version number
+    @antora_version = stdout.strip
+    @logger.info("Using Antora version: #{@antora_version}")
+
+    # Check if source CSS exists
+    unless File.exist?(PATHS[:source_css])
+      @logger.error("Source CSS file not found: #{PATHS[:source_css]}")
+      exit 1
+    end
+
+    # Check if playbook exists
+    unless File.exist?(PATHS[:playbook])
+      @logger.error("Antora playbook not found: #{PATHS[:playbook]}")
+      exit 1
+    end
+  end
+
+  # Ensures the Antora site is built
+  def ensure_site_built
+    # If build directory doesn't exist or is empty, build the site
+    unless File.directory?(PATHS[:build_dir]) && !Dir.empty?(PATHS[:build_dir])
+      @logger.info("Build directory not found or empty. Building Antora site...")
+      build_antora_site
+    end
+
+    # After building, copy the current CSS to the build directory
+    if File.exist?(PATHS[:build_css])
+      @logger.info("Copying current CSS to build directory...")
+      # Store the initial CSS hash
+      @last_css_hash = calculate_file_hash(PATHS[:source_css])
+      copy_css_file
+      open_in_browser
+    else
+      @logger.error("Build CSS path not found after site build: #{PATHS[:build_css]}")
+      exit 1
+    end
+  end
+
+  # Builds the Antora site
+  def build_antora_site
+    @logger.info("Building Antora site...")
+
+    Dir.chdir(PATHS[:antora_dir]) do
+      cmd = 'npx antora playbook.yml'
+
+      # Add --fetch flag if UI bundle is configured as a remote URL in playbook
+      if ui_bundle_is_remote?
+        cmd = 'npx antora --fetch playbook.yml'
+        @logger.info("Remote UI bundle detected, using --fetch flag")
+      end
+
+      if system(cmd)
+        @logger.info("Antora site built successfully")
+        true
+      else
+        @logger.error("Antora site build failed")
+        exit 1
+      end
+    end
+  end
+
+  # Check if the UI bundle in the playbook is configured as a remote URL
+  def ui_bundle_is_remote?
+    return false unless File.exist?(PATHS[:playbook])
+
+    content = File.read(PATHS[:playbook])
+    ui_bundle_line = content.match(/^\s*ui:\s*$.*?^\s*bundle:\s*$.*?^\s*url:\s*(.+?)$/m)
+
+    return false unless ui_bundle_line
+
+    url = ui_bundle_line[1].strip
+    # Consider it remote if it starts with http://, https://, or git://
+    url.start_with?('http://', 'https://', 'git://')
+  end
+
+  # Calculate MD5 hash of a file
+  def calculate_file_hash(file_path)
+    Digest::MD5.hexdigest(File.read(file_path))
+  end
+
+  # Copies the CSS file to the build directory
+  def copy_css_file
+    begin
+      FileUtils.cp(PATHS[:source_css], PATHS[:build_css])
+      @logger.info("CSS file updated: #{PATHS[:build_css]}")
+      true
+    rescue => e
+      @logger.error("Failed to copy CSS file: #{e.message}")
+      false
+    end
+  end
+
+  # Opens the generated HTML file in the default web browser
+  def open_in_browser
+    return if @file_opened
+
+    cmd = OS_BROWSER_COMMANDS.find { |platform, _| RUBY_PLATFORM =~ platform }&.last
+    if cmd
+      system("#{cmd} #{PATHS[:build_dir]}/index.html")
+      @file_opened = true
+      @logger.info("Opened site in browser: #{PATHS[:build_dir]}/index.html")
+    else
+      @logger.warn("Unsupported OS. Please open #{PATHS[:build_dir]}/index.html manually")
+    end
+  end
+
+  # Sets up file listeners to watch for changes and trigger updates
+  def watch_files
+    @logger.info("Watching for changes in #{PATHS[:source_css]}...")
+
+    @listener = Listen.to(File.dirname(PATHS[:source_css]), latency: 0.5) do |modified, added, _|
+      # Skip if we're already processing a change to avoid loops
+      next if @processing_change
+
+      files = modified + added
+      css_file_changed = files.any? { |file| File.basename(file) == File.basename(PATHS[:source_css]) }
+
+      if css_file_changed
+        # Calculate the new hash
+        current_hash = calculate_file_hash(PATHS[:source_css])
+
+        # Only process if the hash has actually changed
+        if current_hash != @last_css_hash
+          @processing_change = true
+          @logger.info("#{PATHS[:source_css]} changed, updating build directory...")
+          copy_css_file
+          @last_css_hash = current_hash
+          @processing_change = false
+        end
+      end
+    end
+
+    @listener.start
+
+    # Print instructions for the user
+    print_instructions
+
+    # Keep the script running until shutdown is requested
+    until @shutdown_requested
+      sleep 1
+    end
+
+    shutdown
+  end
+
+  # Prints usage instructions
+  def print_instructions
+    build_url = "file://#{File.expand_path(PATHS[:build_dir])}/index.html"
+
+    @logger.info("")
+    @logger.info("=== Boostlook Antora Preview ===")
+    @logger.info("CSS file is being watched for changes")
+    @logger.info("Any changes to #{PATHS[:source_css]} will be automatically copied to the build directory")
+    @logger.info("")
+    @logger.info("To view the site, open this URL in your browser:")
+    @logger.info("  #{build_url}")
+    @logger.info("")
+    @logger.info("Press Ctrl+C to stop the preview")
+    @logger.info("================================")
+    @logger.info("")
+  end
+
+  # Sets up signal traps to handle graceful shutdown on interrupt or terminate signals
+  def setup_signal_traps
+    Signal.trap("INT") { @shutdown_requested = true }
+    Signal.trap("TERM") { @shutdown_requested = true }
+  end
+
+  # Performs shutdown procedures, such as stopping the file listener
+  def shutdown
+    @logger.info("Shutting down...")
+    @listener&.stop
+    exit
+  end
+end
+
+# Run the preview
+if __FILE__ == $0
+  BoostlookAntoraPreview.new.run
+end
diff --git a/doc/antora_specimen/content b/doc/antora_specimen/content
new file mode 160000
index 0000000..d1fceb5
--- /dev/null
+++ b/doc/antora_specimen/content
@@ -0,0 +1 @@
+Subproject commit d1fceb5897a578d36f16668881e067ae919b595b
diff --git a/doc/antora_specimen/playbook.yml b/doc/antora_specimen/playbook.yml
new file mode 100644
index 0000000..5f70925
--- /dev/null
+++ b/doc/antora_specimen/playbook.yml
@@ -0,0 +1,21 @@
+site:
+  title: Boostlook Antora Specimen
+  url: /
+  start_page: url::index.adoc
+
+content:
+  sources:
+    - url: ./content/url_component
+    - url: https://github.com/julioest/antora-specimen.git
+      branches: main
+      start_path: specimen_component
+
+ui:
+  bundle:
+    url: ./ui/ui-bundle.zip
+    # Or use the remote URL option
+    # url: https://github.com/boostorg/website-v2-docs/releases/download/ui-master/ui-bundle.zip
+    # snapshot: true
+
+output:
+  dir: ./build/site
diff --git a/doc/antora_specimen/ui/ui-bundle.zip b/doc/antora_specimen/ui/ui-bundle.zip
new file mode 100644
index 0000000..13a0383
Binary files /dev/null and b/doc/antora_specimen/ui/ui-bundle.zip differ