Add new color mode

Adding a new, custom color mode creates a new option in the color mode switcher in the navbar. Users switch between color modes to tailor their reading experience with pre-defined styles.

This guide explains how to add a new color mode to your Redocly project, including adding a custom icon to the color mode switcher.

Before you begin

Make sure you have the following before you begin:

• A Redocly project set up and running locally.
• Moderate comfort with React and CSS.
• Familiar with concept of color modes.

Eject ColorModeIcon component

Ejecting the component allows you to make modifications that are visible to the end-user, such as adding a color mode.

Eject the ColorModeIcon component from the default Redocly theme using the following command:

npx @redocly/cli eject component 'ColorModeSwitcher/ColorModeIcon.tsx'

Add new color mode icon

Add an icon for the new color mode using the following steps:

1. Create a switch case for the new color mode in the ejected file, as in the following example:

   @theme/components/ColorModeSwitcher/ColorModeIcon.tsx

   // ... other code
   function Icon({ mode, className }: ColorModeIconProps) {
     switch (mode) {
       case 'high-contrast':
         // New icon goes here
       case 'dark':
         return <SunIcon data-testid="dark" />;
       // ... additional switch cases
     }
   }

2. Return the new color mode's icon as an <svg> element from the new switch case. Use the following steps to get the HTML code for the icon:

   • Move the icon's .svg file into your Redocly project.
   • Open the file in your code editor.
   • Copy the <svg> HTML element.
   • Important: Pass the className prop through to the <svg> element.

The following example adds an icon for a new color mode called high-contrast:

// ...
function Icon({ mode, className }: ColorModeIconProps) {
  switch (mode) {
    case 'high-contrast':
      return (
        <svg className={className} version="1.1" viewBox="0 0 128 128" xmlns="http://www.w3.org/2000/svg">
          <path d="m62 108v12c0 1.1055 0.89453 2 2 2s2-0.89453 2-2v-12c0-1.1055-0.89453-2-2-2s-2 0.89453-2 2zm43.012-5.8164-8.4844-8.4844c-0.78125-0.78516-2.0469-0.78516-2.8281 0-0.78516 0.78125-0.78516 2.0469 0 2.8281l8.4844 8.4844c0.78125 0.78125 2.0469 0.78125 2.8281 0s0.78125-2.0469 0-2.8281zm-73.539-8.4844-8.4844 8.4844c-0.78125 0.78125-0.78125 2.0469 0 2.8281s2.0469 0.78125 2.8281 0l8.4844-8.4844c0.78516-0.78125 0.78516-2.0469 0-2.8281-0.78125-0.78516-2.0469-0.78516-2.8281 0zm32.527 8.3008c20.973 0 38-17.027 38-38s-17.027-38-38-38-38 17.027-38 38 17.027 38 38 38zm-2-71.945v67.887c-17.836-1.0391-32-15.852-32-33.945s14.164-32.902 32-33.945zm58 31.945h-12c-1.1055 0-2 0.89453-2 2s0.89453 2 2 2h12c1.1055 0 2-0.89453 2-2s-0.89453-2-2-2zm-100 0h-12c-1.1055 0-2 0.89453-2 2s0.89453 2 2 2h12c1.1055 0 2-0.89453 2-2s-0.89453-2-2-2zm82.184-39.012-8.4844 8.4844c-0.78516 0.78125-0.78516 2.0469 0 2.8281 0.78125 0.78516 2.0469 0.78516 2.8281 0l8.4844-8.4844c0.78125-0.78125 0.78125-2.0469 0-2.8281s-2.0469-0.78125-2.8281 0zm-67.883 8.4844-8.4844-8.4844c-0.78125-0.78125-2.0469-0.78125-2.8281 0s-0.78125 2.0469 0 2.8281l8.4844 8.4844c0.78125 0.78516 2.0469 0.78516 2.8281 0 0.78516-0.78125 0.78516-2.0469 0-2.8281zm27.699-23.473v12c0 1.1055 0.89453 2 2 2s2-0.89453 2-2v-12c0-1.1055-0.89453-2-2-2s-2 0.89453-2 2z" fill-rule="evenodd"/>
        </svg>
      );
    case 'dark':
      return <SunIcon data-testid="dark" />;
    // ...
  }
}

Define color mode styles

Define the styling rules for your color mode in the @theme/styles.css file using the :root.className selector.

During initial setup, using placeholder styles can help with testing, as in the following example:

:root.high-contrast {
  --md-content-text-color: red;
  --bg-color: lightgreen;
}

Add color mode to configuration

Add the new color mode to your project configuration, as in the following example:

colorMode: 
  modes: 
    - 'high-contrast'
    - 'light'
    - 'dark'

The colorMode option controls which options are shown to users in the color mode switcher.

Test new color mode

Test the new color mode in your local preview to verify that it works as expected.

• Use the npx @redocly/cli preview command to start your local preview.
• Click the color mode switcher to toggle between color modes.
• Verify that the new color mode icon is visible.
• Verify the new color mode styles are applied correctly.
• In @theme/styles.css, replace placeholder styles with new color mode styles.

Resources

• Learn the foundational concepts of color mode.
• Use CSS to customize color mode styles.
• Add color-mode-specific images to add image elements that change with color mode.