### Programmatic Menu Opening

Source: https://inclusive-components.design/menus-menu-buttons

Example of initializing and opening a menu button programmatically.

```javascript
exampleMenuButton = new MenuButton(document.querySelector('[aria-haspopup]'));

exampleMenuButton.open();
```

--------------------------------

### Install component via NPM

Source: https://inclusive-components.design/a-theme-switcher

Use the NPM command to add the theme switcher package to your project.

```bash
npm i --save react-theme-switch
```

--------------------------------

### Demo markup for toggle sections

Source: https://inclusive-components.design/collapsible-sections

Example structure for toggle-section components with unique IDs for hash tracking.

```html
<main>
  <toggle-section open="false">
    <h2 id="section-1">Section 1</h2>
    <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam non lectus sit amet nunc facilisis molestie. Praesent quis libero et mauris facilisis dignissim at sed nisi.</p> 
    <p>Nullam efficitur porttitor lectus, ac finibus nibh fermentum ac. Phasellus aliquam, nibh non efficitur pharetra, tellus diam posuere lectus, a consequat elit ex nec ligula.</p>
  </toggle-section>
  <toggle-section open="true">
    <h2 id="section-2">Section 2</h2>
    <p>Aliquam erat volutpat. Nulla facilisi. Nunc porttitor, elit non eleifend aliquam, est leo scelerisque nibh, nec faucibus odio urna ac nulla.</p> 
    <p>Maecenas laoreet in metus eget convallis. Vivamus at eleifend felis. Proin non vehicula neque. Etiam eleifend sapien ut nulla malesuada, ac condimentum nisl efficitur.</p>
  </toggle-section>
</main>
```

--------------------------------

### Install inclusive-menu-button via NPM

Source: https://inclusive-components.design/menus-menu-buttons

Use this command to add the inclusive-menu-button package to your project dependencies.

```bash
npm i inclusive-menu-button --save
```

--------------------------------

### HTML structure for toggle sections

Source: https://inclusive-components.design/collapsible-sections

Markup example using the custom toggle-section element.

```html
<main>
  <toggle-section open="false">
    <h2>Section 1</h2>
    <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam non lectus sit amet nunc facilisis molestie. Praesent quis libero et mauris facilisis dignissim at sed nisi.</p> 
    <p>Nullam efficitur porttitor lectus, ac finibus nibh fermentum ac. Phasellus aliquam, nibh non efficitur pharetra, tellus diam posuere lectus, a consequat elit ex nec ligula.</p>
  </toggle-section>
  <toggle-section open="true">
    <h2>Section 2</h2>
    <p>Aliquam erat volutpat. Nulla facilisi. Nunc porttitor, elit non eleifend aliquam, est leo scelerisque nibh, nec faucibus odio urna ac nulla.</p> 
    <p>Maecenas laoreet in metus eget convallis. Vivamus at eleifend felis. Proin non vehicula neque. Etiam eleifend sapien ut nulla malesuada, ac condimentum nisl efficitur.</p>
  </toggle-section>
</main>
```

--------------------------------

### Implement responsive table component in React

Source: https://inclusive-components.design/data-tables

A full component example demonstrating dynamic tabindex management based on scrollability.

```javascript
class Table extends React.Component {  
  constructor(props) {
    super(props)
    this.state = {
      tabindex: null
    }
  }
  componentDidMount() {
    let container = ReactDOM.findDOMNode(this.refs.container);
    let scrollable = container.scrollWidth > container.clientWidth;
    this.setState({
      tabindex: scrollable ? '0' : null
    });
  }
  render() {
    const captionID = 'caption-' + Math.random().toString(36).substr(2, 9);
    return (
      <div
        className="table-container"
        ref="container"
        tabIndex={this.state.tabindex}
        aria-labelledby={captionID}
      >
        <!-- table here -->
      </div>
    );
  }
}
```

--------------------------------

### Render ThemeSwitch markup

Source: https://inclusive-components.design/a-theme-switcher

Example JSX structure for the theme toggle button and embedded stylesheet.

```jsx
<div>  
   <button aria-pressed="false">
      dark theme:
      <span aria-hidden="true">off</span>
   </button>
   <style media="none">
      html { filter: invert(100%); background: #fefefe }
      * { background-color: inherit }
      img:not([src*=".svg"]), video { filter: invert(100%) }
   </style>
</div>  
```

--------------------------------

### SVG Use Element Implementation

Source: https://inclusive-components.design/collapsible-sections

Example of using the SVG <use> element for icon reuse, noting the limitation regarding CSS targeting.

```xml
<button aria-expanded="false">
  My section
  <svg viewBox="0 0 10 10 aria-hidden="true" focusable="false">
    <use xlink:href="#plusminus"/>
  </svg>
</button>
```

--------------------------------

### Web component definition

Source: https://inclusive-components.design/collapsible-sections

JavaScript implementation of the custom element including template and Shadow DOM setup.

```javascript
(function() {
  // Check for <template> support
  if ('content' in document.createElement('template')) {
    const tmpl = document.createElement('template')

    // Create the web component's template
    // featuring a <slot> for the Light DOM content
    tmpl.innerHTML = `
      <h2>
        <button aria-expanded="false">
          <svg aria-hidden="true" focusable="false" viewBox="0 0 10 10">
            <rect class="vert" height="8" width="2" y="1" x="4"/>
            <rect height="2" width="8" y="4" x="1"/>
          </svg>
        </button>
      </h2>
      <div class="content" hidden>
        <slot></slot>
      </div>
      <style>
        h2 {
          margin: 0;
        }

        h2 button {
          all: inherit;
          box-sizing: border-box;
          display: flex;
          justify-content: space-between;
          width: 100%;
          padding: 0.5em 0;
        }

        h2 button:focus svg {
          outline: 2px solid;
        }

        button svg {
          height: 1em;
          margin-left: 0.5em;
        }

        [aria-expanded="true"] .vert {
          display: none;
        }

        [aria-expanded] rect {
          fill: currentColor;
        }
      </style>
    `
    // Check for latest Shadow DOM syntax support
    if (document.head.attachShadow) {
      class ToggleSection extends HTMLElement {
        constructor() {
          super()

          // Make the host element a region
          this.setAttribute('role', 'region')

          // Create a `shadowRoot` and populate from template 
          this.attachShadow({ mode: 'open' })
          this.shadowRoot.appendChild(tmpl.content.cloneNode(true))

          // Assign the toggle button
          this.btn = this.shadowRoot.querySelector('h2 button')

          // Get the first element in Light DOM
          // and cast its heading level (which should, but may not, exist)
          const oldHeading = this.querySelector(':first-child')
          let level = parseInt(oldHeading.tagName.substr(1))
```

--------------------------------

### Define the Shadow DOM heading structure

Source: https://inclusive-components.design/collapsible-sections

Example HTML structure for the collapsible heading containing a button and icon.

```html
<h2 aria-level="3">  
  <button aria-expanded="false">
    <svg aria-hidden="true" focusable="false" viewBox="0 0 10 10">
      <rect class="vert" height="8" width="2" y="1" x="4"/>
      <rect height="2" width="8" y="4" x="1"/>
    </svg>
  </button>
</h2>
```

--------------------------------

### Non-Interactive Element Focusability

Source: https://inclusive-components.design/tabbed-interfaces

Examples demonstrating the difference between making an element focusable via tab order versus script-only focus.

```html
<h2 tabindex="0">Section 3<h2>
```

```html
<h2 tabindex="-1">Application View<h2>
```

--------------------------------

### Invalid focusable element example

Source: https://inclusive-components.design/rss

An example of an element that violates WCAG 2.4.3 by making a non-interactive element focusable via tabindex.

```html
<h2 tabindex="0">Section 3<h2>
```

--------------------------------

### Initialize React project

Source: https://inclusive-components.design/a-theme-switcher

Commands to set up a new React development environment.

```bash
npm i -g create-react-app  
create-react-app theme-switch  
cd theme-switch  
npm start  
```

--------------------------------

### Empty Navigation Region

Source: https://inclusive-components.design/menus-menu-buttons

Example of an empty navigation region when the list is hidden from screen readers.

```html
<nav id="navigation">
</nav>
```

--------------------------------

### Import ThemeSwitch component

Source: https://inclusive-components.design/a-theme-switcher

Import the component into the App.js file.

```javascript
import ThemeSwitch from './components/ThemeSwitch'  
```

--------------------------------

### Apply menu and menuitem roles to a list

Source: https://inclusive-components.design/menus-menu-buttons

Demonstrates how to augment a standard list with WAI-ARIA menu semantics.

```html
<ul role="menu">
  <li role="menuitem">Item 1</li>
  <li role="menuitem">Item 2</li>
  <li role="menuitem">Item 3</li>
</ul>
```

--------------------------------

### Style instructions for touch devices

Source: https://inclusive-components.design/rss

Use the .touch class to override default instruction visibility when touch interaction is detected.

```css
.touch .instructions p { display: none !important; } .touch .instructions #touch { display: block !important; }
```

--------------------------------

### Empty Navigation Region

Source: https://inclusive-components.design/rss

An example of an empty navigation region, which can occur if the button is placed outside the nav element.

```html
<nav id="navigation"> </nav>
```

--------------------------------

### Initialize localStorage alias

Source: https://inclusive-components.design/a-theme-switcher

Create a safe reference to localStorage to avoid linting errors.

```javascript
this.store = typeof localStorage === 'undefined' ? null : localStorage;  
```

--------------------------------

### Full CSS styling for target-based navigation

Source: https://inclusive-components.design/tabbed-interfaces

Complete stylesheet including typography, layout, and the :target visibility logic.

```css
@import url('https://fonts.googleapis.com/css?family=Asap:400,400i,700');

html {
  font-size: 125%;
  font-family: Asap, sans-serif;
}

body {
  max-width: 40rem;
  padding: 0 1rem;
  margin: 1.5rem auto;
}

* {
  color: inherit;
}

[aria-labelledby="toc-heading"] {
  padding: 1rem;
  border: 2px solid;
}

[aria-labelledby="toc-heading"] * {
  margin: 0;
}

section:not(:target) {
  display: none;
}
```

--------------------------------

### Menu Button Open Method

Source: https://inclusive-components.design/menus-menu-buttons

Implementation of the open method to update aria-expanded, reveal the menu, and focus the first enabled item.

```javascript
MenuButton.prototype.open = function () {
  this.button.setAttribute('aria-expanded', true);
  this.menu.hidden = false;
  this.menu.querySelector(':not([disabled])').focus();

  return this;
}
```

--------------------------------

### Card with Nested Links

Source: https://inclusive-components.design/rss

An example of adding an interactive author link inside a block-level card link, which can cause accessibility issues.

```html
<li>
 <a href="/card-design-woes">
 <img src="/path/to/image.png" alt="">
 <h2>Card design woes</h2>
 <p>Ten common pitfalls to avoid when designing card components.</p>
 <small>By <a href="/author/heydon">Heydon Pickering</a></small>
 </a>
 </li>
```

--------------------------------

### Basic Menu Button Structure

Source: https://inclusive-components.design/menus-menu-buttons

A standard menu button implementation using a button trigger and a container with the menu role.

```html
<button aria-haspopup="true" aria-expanded="false">
  Difficulty
  <span aria-hidden="true">&#x25be;</span>
</button>
<div role="menu">
  <button role="menuitem">Easy</button>
  <button role="menuitem">Medium</button>
  <button role="menuitem">Incredibly Hard</button>
</div>
```

--------------------------------

### Instantiate an on-demand live region

Source: https://inclusive-components.design/rss

Use the OnDemandLiveRegion module to programmatically trigger screen reader announcements for events in your scripts.

```javascript
const liveRegion = new OnDemandLiveRegion()
liveRegion.say('Take a short break!')
```

--------------------------------

### Non-Accessible Data Table

Source: https://inclusive-components.design/data-tables

An example of a table that lacks semantic header elements, making it difficult for screen readers to interpret the data structure.

```html
<table>  
    <tr>
        <td>Column header 1</td>
        <td>Column header 2</td>
    </tr>
    <tr>
        <td>Row one, first cell</td>
        <td>Row one, second cell</td>
    </tr>
</table>  
```

--------------------------------

### Initialize Toggletip Functionality

Source: https://inclusive-components.design/tooltips-toggletips

JavaScript to dynamically create the toggletip button and handle interaction events.

```javascript
(function() {
  // Get all the toggletip buttons
  var toggletipTexts = document.querySelectorAll('[data-toggletip]');

  // Iterate over them
  Array.prototype.forEach.call(toggletipTexts, function(toggletipText) {
    // Create the container element
    var container = document.createElement('span');
    container.setAttribute('class', 'toggletip-container');
    
    // Put it before the original element in the DOM
    toggletipText.parentNode.insertBefore(container, toggletipText);
    
    // Create the button element
    var toggletip = document.createElement('button');
    toggletip.setAttribute('type', 'button');
    toggletip.setAttribute('aria-label', 'more info');
    toggletip.setAttribute('data-toggletip-content', toggletipText.textContent);
    toggletip.textContent = 'i';
    
    // Place the button element in the container
    container.appendChild(toggletip);
    
    // Create the live region
    var liveRegion = document.createElement('span');
    liveRegion.setAttribute('role', 'status');
    
    // Place the live region in the container
    container.appendChild(liveRegion);
    
    // Remove the original element
    toggletipText.parentNode.removeChild(toggletipText);
    
    // Build `data-tooltip-content` 
    var message = toggletip.getAttribute('data-toggletip-content');
    toggletip.setAttribute('data-toggletip-content', message);
    toggletip.removeAttribute('title');
    
    // Get the message from the data-content element
    var message = toggletip.getAttribute('data-toggletip-content');

    // Get the live region element
    var liveRegion = toggletip.nextElementSibling;

    // Toggle the message
    toggletip.addEventListener('click', function() {
        liveRegion.innerHTML = '';
        window.setTimeout(function() {
          liveRegion.innerHTML = '<span class="toggletip-bubble">'+ message +'</span>';
        }, 100);
    });

    // Close on outside click
    document.addEventListener('click', function (e) {
      if (toggletip !== e.target) {
        liveRegion.innerHTML = '';
      }                        
    });

    // Remove toggletip on ESC
    toggletip.addEventListener('keydown', function(e) {
      if ((e.keyCode || e.which) === 27)
      liveRegion.innerHTML = '';
    });
    
    // Remove on blur
    toggletip.addEventListener('blur', function (e) {
      liveRegion.innerHTML = '';
    });
  });
}());
```

--------------------------------

### Define a reusable SVG symbol

Source: https://inclusive-components.design/rss

Define icons as symbols at the start of the document to reduce DOM bloat when using multiple instances of the same icon.

```html
<body> <svg style="display: none"> <symbol id="bin-icon" viewBox="0 0 20 20"> <path d="[path data here]"> </symbol> </svg>
```

--------------------------------

### Procedural Live Region Module

Source: https://inclusive-components.design/notifications

Instantiate and use a live region module to programmatically announce messages to screen readers.

```javascript
const liveRegion = new OnDemandLiveRegion()

liveRegion.say('Take a short break!')  
```

--------------------------------

### Redundant title attribute example

Source: https://inclusive-components.design/tooltips-toggletips

Demonstrates an anti-pattern where the title attribute repeats the visible text node, causing unnecessary repetition for screen readers.

```html
<a href="/some/path" title="Heydon's special page">Heydon's special page</a>
```

--------------------------------

### Define Live Region

Source: https://inclusive-components.design/rss

Create a container for dynamic content updates that screen readers will announce automatically.

```html
<div role="status" aria-live="polite"> <!-- add content to hear it spoken --> </div>
```

--------------------------------

### Standard Navigation Structure

Source: https://inclusive-components.design/menus-menu-buttons

A standard navigation list structure without JavaScript enhancement.

```html
<nav id="navigation">
  <ul>
    <li><a href="/">Home</a></li>
    <li><a href="/about">About</a></li>
    <li><a href="/shop">Shop</a></li>
    <li><a href="/content">Content</a></li>
  </ul>
</nav>
```

--------------------------------

### Feature detection for Web Components

Source: https://inclusive-components.design/collapsible-sections

Check for template and Shadow DOM support before initializing the component.

```javascript
if ('content' in document.createElement('template')) {  
  // Define the <template> for the web component

  if (document.head.attachShadow) {
    // Define the web component using the v1 syntax
  }
}

```

--------------------------------

### Define toggle and status helper functions

Source: https://inclusive-components.design/a-theme-switcher

Implement helper methods to check and update the theme state.

```javascript
  isActive = () => this.state.active;

  toggle = () => {
    this.setState({
      active: !this.isActive()
    });
  }
```

--------------------------------

### Initial Navigation Link Structure

Source: https://inclusive-components.design/menus-menu-buttons

A basic navigation structure using a link to jump to the navigation section.

```html
<a href="#navigation">navigation</a>
<!-- some content here perhaps -->
<nav id="navigation">
  <ul>
    <li><a href="/">Home</a></li>
    <li><a href="/about">About</a></li>
    <li><a href="/shop">Shop</a></li>
    <li><a href="/content">Content</a></li>
  </ul>
</nav>
```

--------------------------------

### Basic Live Region Implementation

Source: https://inclusive-components.design/notifications

Use both role="status" and aria-live="polite" to maximize compatibility across different browser and assistive technology combinations.

```html
<div role="status" aria-live="polite">  
</div>  
```

```html
<div role="status" aria-live="polite">  
  Take a short break!
</div>  
```

--------------------------------

### Style touch-specific instructions

Source: https://inclusive-components.design/a-content-slider

CSS rules to hide keyboard instructions and display touch-specific messages when the touch class is present.

```css
.touch .instructions p {
  display: none !important;
}

.touch .instructions #touch {
  display: block !important;
}
```

--------------------------------

### Detect touch interaction with JavaScript

Source: https://inclusive-components.design/rss

Listen for a single touchstart event to add a class to the body, then remove the listener to avoid redundant execution.

```javascript
window.addEventListener('touchstart', function touched() { document.body.classList.add('touch') window.removeEventListener('touchstart', touched, false) }, false)
```

--------------------------------

### Integrate ThemeSwitch into App.js

Source: https://inclusive-components.design/a-theme-switcher

Add the ThemeSwitch component to the main application render function.

```javascript
class App extends Component {  
  render() {
    return (
      <div className="App">
        <div className="App-header">
          <img src={logo} className="App-logo" alt="logo" />
          <h2>Welcome to React</h2>
        </div>
        <p className="App-intro">
          To get started, edit {gfm-js-extract-pre-1} and save to reload.
        </p>
        <ThemeSwitch/>
      </div>
    );
  }
}
```

--------------------------------

### Toggle responsive display via CSS

Source: https://inclusive-components.design/rss

Uses media queries to switch between table and list layouts based on viewport width.

```css
@media (min-width: 400px) { .table-container { display: block; } .lists-container { display: none; } }
```

--------------------------------

### Listen for the choose event

Source: https://inclusive-components.design/menus-menu-buttons

Attaches an event listener to update the live region content when a menu item is selected.

```javascript
exampleMenuButton.addEventListener('choose', function (e) {
  // Get the node's text content (label)
  var choiceLabel = e.details.choice.textContent;

  // Get the live region node
  var liveRegion = document.getElementById('menuFeedback');

  // Populate the live region
  liveRegion.textContent = `Your difficulty level is  ${choiceLabel}`;
}):
```

--------------------------------

### Implement Progressive Enhancement Navigation Link

Source: https://inclusive-components.design/rss

Provides a fallback navigation link for environments without JavaScript, pointing to a navigation block further down the document.

```html
<a href="#navigation">navigation</a> <!-- some content here perhaps --> <nav id="navigation"> <ul> <li><a href="/">Home</a></li> <li><a href="/about">About</a></li> <li><a href="/shop">Shop</a></li> <li><a href="/content">Content</a></li> </ul> </nav>
```

--------------------------------

### Initialize component state

Source: https://inclusive-components.design/a-theme-switcher

Set the initial active state for the theme switcher in the constructor.

```javascript
constructor(props) {  
   super(props);

   this.state = {
      active: 'false'
   };
}
```

--------------------------------

### Implement CSS-based Tooltips

Source: https://inclusive-components.design/rss

Use CSS to show tooltips on hover and focus states for elements with the tooltip role.

```css
[role="tooltip"] { display: none; } button:hover + [role="tooltip"], button:focus + [role="tooltip"] { display: block; }
```

--------------------------------

### Associate slider with instructions using aria-describedby

Source: https://inclusive-components.design/rss

Use aria-describedby to link a region to an element containing descriptive text for screen readers.

```html
<div role="region" aria-label="gallery" tabindex="0" aria-describedby="focus"> <!-- list of gallery pictures --> </div> <div class="instructions"> <p id="hover">scroll for more</p> <p id="focus">use your arrow keys for more</p> </div>
```

--------------------------------

### Implement Algorithmic Margin Management

Source: https://inclusive-components.design/cards

Comprehensive CSS for managing spacing and alignment within the card component.

```css
.card, .card .text {
  display: flex;
  flex-direction: column;
}

.card .text {
  flex-grow: 1;
}

.card .text > * + * {
  margin-top: 0.75rem;
}

.card .text :last-child {
  margin-top: auto;
}

.card .text :nth-last-child(2) {
  margin-bottom: 0.75rem;
}
```

--------------------------------

### Enhance Layout with CSS Grid

Source: https://inclusive-components.design/cards

Uses @supports to provide a responsive grid layout for cards while maintaining a fallback for older browsers.

```css
.card .text {
  max-width: 60ch;
}

.card + .card {
    margin-top: 1.5rem;
}

@supports (display: grid) {
    .cards > ul {
        display: grid;
        grid-template-columns: repeat(auto-fill, minmax(15rem, 1fr));
        grid-gap: 1.5rem;
    }

    .card + .card {
        margin-top: 0;
    }
}
```

--------------------------------

### Toggle Interface Visibility with CSS Media Queries

Source: https://inclusive-components.design/data-tables

Uses media queries to switch between table and list views based on viewport width.

```css
@media (min-width: 400px) {
  .table-container {
    display: block;
  }

  .lists-container {
    display: none;
  }
}
```

--------------------------------

### Handle URL Hash Navigation

Source: https://inclusive-components.design/rss

Checks the URL hash on component initialization to automatically expand the section and focus the button if it matches the component's ID.

```javascript
connectedCallback() {
 if (window.location.hash.substr(1) === this.heading.id) {
 this.setAttribute('open', 'true')
 this.btn.focus()
 }
}
```

--------------------------------

### Implementing a true menu button

Source: https://inclusive-components.design/rss

Shows the structure of a menu button component using aria-haspopup and aria-expanded, with menu items defined as buttons.

```html
<button aria-haspopup="true" aria-expanded="false">
Difficulty
<span aria-hidden="true">&#x25be;</span>
</button>
<div role="menu">
<button role="menuitem">Easy</button>
<button role="menuitem">Medium</button>
<button role="menuitem">Incredibly Hard</button>
</div>
```

--------------------------------

### Initialize Component State

Source: https://inclusive-components.design/rss

Setting the initial active state within the component constructor.

```javascript
constructor(props) { super(props); this.state = { active: 'false' }; }
```

--------------------------------

### Static Todo List Structure

Source: https://inclusive-components.design/a-todo-list

A semantic HTML structure for a todo list using an unordered list container to ensure screen reader compatibility.

```html
<section aria-labelledby="todos-label">
  <h1 id="todos-label">My Todo List</h1>
  <ul>
    <li>
      Pick up kids from school
    </li>
    <li>
      Learn Haskell
    </li>
    <li>
      Sleep
    </li>
  </ul>
</section>
```

--------------------------------

### Basic Todo Input Form

Source: https://inclusive-components.design/a-todo-list

A standard form structure for adding todo items, ensuring reliable 'Enter' key submission behavior.

```html
<form>
  <input type="text" placeholder="E.g. Adopt an owl">
  <button type="submit">Add</button>
</form>
```

--------------------------------

### Associate call-to-action with aria-describedby

Source: https://inclusive-components.design/cards

Link the call-to-action text to the heading using aria-describedby to provide context to screen reader users.

```html
<li>  
    <img src="/path/to/image.png" alt="">
    <h2>
        <a href="/card-design-woes" aria-describedby="desc-card-design-woes">Card design woes</a>
    </h2>
    <p>Ten common pitfalls to avoid when designing card components.</p>
    <span class="cta" aria-hidden="true" id="desc-card-design-woes">read more</span>
    <small>By Heydon Pickering</small>
</li>  

```

--------------------------------

### Apply saved theme on mount

Source: https://inclusive-components.design/a-theme-switcher

Retrieve the stored theme preference when the component mounts.

```javascript
componentDidMount() {  
  if (this.store) {
    this.setState({
      active: this.store.getItem('ThemeSwitch') || false
    });
  }
}
```

--------------------------------

### Apply Basic CSS Theme Inversion

Source: https://inclusive-components.design/rss

Sets a root background color and inverts the colors of the entire page.

```css
:root { background-color: #fefefe; filter: invert(100%); }
```

--------------------------------

### Basic Navigation Structure

Source: https://inclusive-components.design/rss

A standard navigation menu structure intended for use when JavaScript is unavailable.

```html
<nav id="navigation"> <ul> <li><a href="/">Home</a></li> <li><a href="/about">About</a></li> <li><a href="/shop">Shop</a></li> <li><a href="/content">Content</a></li> </ul> </nav>
```

--------------------------------

### Set default hash on page load

Source: https://inclusive-components.design/tabbed-interfaces

JavaScript to ensure a default section is active when the page first loads.

```javascript
// Choose the default section on page load
// And scroll to the top to show nav
window.onload = function () {
  window.location.hash = 'section1'
  document.documentElement.scrollTop = 0
}
```

--------------------------------

### Define the ToggleSection Web Component

Source: https://inclusive-components.design/collapsible-sections

Initializes the custom element and attaches the Shadow DOM using a template.

```javascript
class ToggleSection extends HTMLElement {  
  constructor() {
    super()

    this.attachShadow({ mode: 'open' })
    this.shadowRoot.appendChild(tmpl.content.cloneNode(true))
  }
}
```

--------------------------------

### Update live region content via JavaScript

Source: https://inclusive-components.design/rss

Listen for menu selection events and update the text content of the live region to notify users.

```javascript
exampleMenuButton.addEventListener('choose', function (e) { // Get the node's text content (label) var choiceLabel = e.details.choice.textContent; // Get the live region node var liveRegion = document.getElementById('menuFeedback'); // Populate the live region liveRegion.textContent = `Your difficulty level is ${choiceLabel}`; }):
```

--------------------------------

### Apply flexbox layout to gallery

Source: https://inclusive-components.design/a-content-slider

Configures the gallery container and list items to display slides at full width.

```css
[aria-label="gallery"] ul {
  display: flex;
}

[aria-label="gallery"] li {
  list-style: none;
  flex: 0 0 100%;
}
```

--------------------------------

### Basic Notification List Structure

Source: https://inclusive-components.design/rss

Initial structure for a notification list using buttons for toggling states.

```html
<h2>Notifications</h2> <ul> <li> Notify by email <button> <span>on</span> <span>off</span> </button> </li> <li> Notify by SMS <button> <span>on</span> <span>off</span> </button> </li> <li> Notify by fax <button> <span>on</span> <span>off</span> </button> </li> <li> Notify by smoke signal <button> <span>on</span> <span>off</span> </button> </li> </ul>
```

--------------------------------

### Implement basic collapsible markup

Source: https://inclusive-components.design/rss

Use a button element inside a heading to ensure the interaction is communicated to assistive technology.

```html
<h2><button>My section</button></h2> <div> <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Cras efficitur laoreet massa. Nam eu porta dolor. Vestibulum pulvinar lorem et nisl tempor lacinia.</p> <p>Cras mi nisl, semper ut gravida sed, vulputate vel mauris. In dignissim aliquet fermentum. Donec arcu nunc, tempor sed nunc id, dapibus ornare dolor.</p> </div>
```

--------------------------------

### State Helper Functions

Source: https://inclusive-components.design/rss

Functions to check and toggle the current theme state.

```javascript
isActive = () => this.state.active; toggle = () => { this.setState({ active: !this.isActive() }); }
```

--------------------------------

### Manage focus on view elements

Source: https://inclusive-components.design/tabbed-interfaces

Apply the region role and tabindex to view containers to allow programmatic focus management.

```html
<div aria-label="Home" role="region" tabindex="-1">  
  ...
</div>  

```

--------------------------------

### Render mobile-friendly definition list

Source: https://inclusive-components.design/rss

Transforms table data into a series of definition lists for narrow viewports, using React Fragments to avoid unnecessary wrapper elements.

```jsx
<div className="lists-container"> <h2>{this.props.caption}</h2> {this.props.rows.map((row, i) => <div key={i}> <h3>{row[0]}</h3> <dl> {this.props.headers.map((header, i) => i > 0 && <React.Fragment key={i}> <dt>{header}</dt> <dd>{row[i]}</dd> </React.Fragment> )} </dl> </div> )} </div>
```

--------------------------------

### Implement basic collapsible sections with JavaScript

Source: https://inclusive-components.design/rss

A minimal script to toggle the visibility of sections based on aria-expanded attributes.

```javascript
(function() { const headings = document.querySelectorAll('h2') Array.prototype.forEach.call(headings, heading => { let btn = heading.querySelector('button') let target = heading.nextElementSibling btn.onclick = () => { let expanded = btn.getAttribute('aria-expanded') === 'true' || false btn.setAttribute('aria-expanded', !expanded) target.hidden = expanded } }) })()
```

--------------------------------

### Handle URL hash on component load

Source: https://inclusive-components.design/collapsible-sections

Use connectedCallback to check for a matching hash and expand the section automatically.

```javascript
connectedCallback() {  
  if (window.location.hash.substr(1) === this.heading.id) {
    this.setAttribute('open', 'true')
    this.btn.focus()
  } 
}
```