Customization

Theming

All component styles reference design tokens, which are defined as CSS custom properties. By overriding these properties, you can customize the look and feel of your application.

Some items you can customize this way are the brand color (which is used in primary buttons, form controls, and more), font stacks, spacing density, border roundness, and shadow depth.

Place all your overrides inside a block that targets the following selector: :root, ::backdrop, .light-mode, .dark-mode, .modal, .drawer. While this selector is a bit unwieldy, it’s needed to properly support all the ways these tokens are used.

About This Selector

Selector	Target	Purpose
`:root`	The root element of the document	This is where you typically define global custom properties, since most elements inherit from it.
`::backdrop`	Backdrop of Modal and Drawer	To support older browsers where the backdrop doesn’t inherit from `:root` (source).
`.light-mode`, `.dark-mode`	Elements with a color mode override	Allows the color mode to be overridden.
`.modal`, `.drawer`	Modal and Drawer components	Ensures these components match the system color mode by default rather than inheriting from the parent element.

Make sure to define your overrides after you import concord.css to ensure they take precedence over the default values.

Example

:root,
::backdrop,
.light-mode,
.dark-mode,
.modal,
.drawer {
  /* Override brand color */
  --color-brand-1: light-dark(#00023c, #e2f0ff);
  --color-brand-2: light-dark(#081f59, #bdd8ff);
  --color-brand-3: light-dark(#1c3672, #93b5fb);
  --color-brand-4: light-dark(#365290, #6f90d3);
  --color-brand-5: light-dark(#516fb0, #5675b6);
  --color-brand-6: light-dark(#6c8ccf, #3e5b9a);
  --color-brand-7: light-dark(#89abf0, #27427f);
  --color-brand-8: light-dark(#abccff, #152e68);
  --color-brand-9: light-dark(#ddedff, #000a44);
  --color-brand-transparent: light-dark(
    #516fb066,
    #5675b680
  );
  --color-brand-extra-transparent: light-dark(
    #516fb033,
    #5675b659
  );

  /* Make borders less round */
  --radius-s: 2px;
  --radius-m: 4px;
  --radius-l: 8px;
  --radius-xl: 22px;
  --radius-2xl: 48px;
}

By default, the App Header has a solid background and a border at the bottom. You can replace the background with a subtle, transparent gradient and remove the border by adding the class transparent to the header element. This can be useful if the page has a hero image or other content that should be visible behind the header.

When doing this, make sure to test the legibility of your header content in both light and dark mode, as well as at different window sizes and zoom levels.

Customization

Theming

Example

Making the App Header Transparent