Online Payments

Design Foundations

Design Foundations

Design Foundations

Design foundations define the visual principles and design tokens used across all components. These rules must be followed consistently to ensure visual alignment with the checkout.


Accessibility (WCAG 2.2 AA)

All UI elements comply with WCAG 2.2 AA.

Key requirements include:

  • All functionality is operable using a keyboard only.
  • A logical and predictable tab order is maintained.
  • Focus indicators are always visible.
  • Minimum contrast requirements are met for text and non-text UI elements.
  • Color is not the only means of conveying information.
  • Interactive elements meet minimum touch target size requirements.

All components and states described in this stylebook are designed to meet these requirements.

More information


Color system

Colors are defined using functional tokens rather than decorative names.

Backgrounds

  • Page background: --Background-BG-White
  • Surface background: --Background-BG-White

Text

  • Default text: --Text-Default
  • Muted text: defined in Typography

Functional colors

  • Primary action: --Functional-Base-1
  • Borders: --Functional-Base-4

Color combinations must meet WCAG contrast requirements.


Surfaces and layout

The checkout uses flat surfaces.

Visual separation is achieved using:

  • Background color
  • Borders
  • Spacing

No elevation or drop shadow is used.


Borders

Borders are used to define component boundaries and selected states.

  • Default border width: 1px
  • Selected state border width: 3px
  • Border radius is defined per component

Borders must meet non-text contrast requirements (3:1).


Spacing

Spacing is consistent and intentional.

  • Internal spacing is defined per component
  • Vertical rhythm is prioritized over decorative separation
  • Excessive nesting and dense layouts should be avoided