v5.2.0 design refresh, plus responsive offcanvas classes (#35736)

* Add responsive offcanvas classes

- Updates navbar-expand classes to de-dupe some styles—these shouldn't interfere now.
- Adds some JS to the offcanvas component to help with responsiveness

Co-Authored-By: GeoSot <geo.sotis@gmail.com>

* Redesign homepage, docs, and examples

Homepage:

- New Bootstrap purple navbar
- Redesigned masthead
- Rewrote and redesigned homepage content
- Replace Copy text with icons like Bootstrap Icons site across all ClipboardJS instances
- Fixed padding issues in site footer
- Match homepage button styles to examples page, use gap instead of tons of responsive margin utils

Docs:

- New navbar, no more subnav. Migrated search and version picker into the main navbar and refreshed the design of it all, including the responsive toggles.
- New sidebar navigation is always expanded, and now features Bootstrap Icons alongside section headings
- Sidebar navigation autoscrolls to active link for better usability
- Subnav and navbar padding issues ironed out
- Enhanced the version picker in anticipation of v5.2: we can now link right to the same page in the previous version.
- Redesign callouts to add more color to our pages
- Collapse table of contents on mobile
- Cleanup and redesign button styles with CSS variables
- Update design for subnav version dropdown
- Update highlight and example to be full-width until md
- Improve the Added In badges
- Turn the ToC into a well on mobile
- Redesign code snippets to better house two action buttons

Examples:

- Redesign Examples page layout
- Add new example for responsive offcanvases in navbars

* Convert offcanvas to CSS vars

* Feat: add resize handler to Offcanvas.js.

If we could use as default the `.offcanvas` class without modifiers, we then, could add a simplified selector
The selector itself, ignores the .offcanvas class as it doesn't have any responsive behavior
The `aria-modal` addon is to protect us, selection backdrop elements

* Separate examples code, Add some selectors, fix stackblitz btn

Co-authored-by: GeoSot <geo.sotis@gmail.com>

site/data/examples.yml

@@ -63,6 +63,8 @@
   examples:
     - name: Navbars
       description: "Demonstration of all responsive and container options for the navbar."
+    - name: Navbars offcanvas
+      description: "Same as the Navbars example, but with our offcanvas component."
     - name: Navbar static
       description: "Single navbar example of a static top navbar along with some additional content."
     - name: Navbar fixed

site/data/plugins.yml

@@ -0,0 +1,47 @@
+- name: Alert
+  description: Show and hide alert messages to your users.
+  link: components/alerts/#javascript-behavior
+
+- name: Button
+  description: Programmatically control the active state for buttons.
+  link: components/buttons/#button-plugin
+
+- name: Carousel
+  description: Add slideshows to any page, including support for crossfade.
+  link: components/carousel/
+
+- name: Collapse
+  description: Expand and collapse areas of content, or create accordions.
+  link: components/collapse/
+
+- name: Dropdown
+  description: Create menus of links, actions, forms, and more.
+  link: components/dropdowns/
+
+- name: Modal
+  description: Add flexible and responsive dialogs to your project.
+  link: components/modal/
+
+- name: Offcanvas
+  description: Build and toggle hidden sidebars into any page.
+  link: components/offcanvas/
+
+- name: Popover
+  description: Create custom overlays. Built on Popper.js.
+  link: components/popovers/
+
+- name: Scrollspy
+  description: Automatically update active nav links based on page scroll.
+  link: components/scrollspy/
+
+- name: Tab
+  description: Allow Bootstrap nav components to toggle contents.
+  link: components/navs-tabs/
+
+- name: Toast
+  description: Show and hide notifications to your visitors.
+  link: components/toasts/
+
+- name: Tooltip
+  description: Replace browser tooltips with custom ones. Built on Popper.js.
+  link: components/tooltips/

site/data/sidebar.yml

@@ -2,6 +2,8 @@
 # The logic for the sidebar generation is in "site/layouts/partials/docs-sidebar.html".
 
 - title: Getting started
+  icon: book-half
+  icon_color: indigo
   pages:
     - title: Introduction
     - title: Download
@@ -16,6 +18,8 @@
     - title: Contribute
 
 - title: Customize
+  icon: palette2
+  icon_color: pink
   pages:
     - title: Overview
     - title: Sass
@@ -26,6 +30,8 @@
     - title: Optimize
 
 - title: Layout
+  icon: grid-fill
+  icon_color: teal
   pages:
     - title: Breakpoints
     - title: Containers
@@ -37,6 +43,8 @@
     - title: CSS Grid
 
 - title: Content
+  icon: file-earmark-richtext
+  icon_color: gray
   pages:
     - title: Reboot
     - title: Typography
@@ -45,6 +53,8 @@
     - title: Figures
 
 - title: Forms
+  icon: ui-radios
+  icon_color: blue
   pages:
     - title: Overview
     - title: Form control
@@ -57,6 +67,8 @@
     - title: Validation
 
 - title: Components
+  icon: menu-button-wide-fill
+  icon_color: cyan
   pages:
     - title: Accordion
     - title: Alerts
@@ -84,6 +96,8 @@
     - title: Tooltips
 
 - title: Helpers
+  icon: magic
+  icon_color: orange
   pages:
     - title: Clearfix
     - title: Colored links
@@ -96,6 +110,8 @@
     - title: Vertical rule
 
 - title: Utilities
+  icon: braces-asterisk
+  icon_color: red
   pages:
     - title: API
     - title: Background
@@ -116,11 +132,15 @@
     - title: Visibility
 
 - title: Extend
+  icon: tools
+  icon_color: blue
   pages:
     - title: Approach
     - title: Icons
 
 - title: About
+  icon: globe2
+  icon_color: indigo
   pages:
     - title: Overview
     - title: Team