High Contrast Mode & Forced Colors Architecture

On Windows, millions of users with severe vision impairment rely on Windows High Contrast Mode (now standardized across all browsers as Forced Colors Mode).

When Forced Colors Mode is active:

• The operating system completely strips all authored background colors, gradients, and custom text colors.
• It replaces them with a high-contrast user-chosen system palette (e.g., pure black background, pure white text, yellow links).
• The Trap: If a button relied on a background color without a physical border (border: none; background: #0052cc), in Forced Colors Mode the background vanishes, turning the button into an invisible floating word!

Design System Solution: Always give interactive components a transparent border: border: 1px solid transparent;. In standard mode, the border is invisible; in Forced Colors Mode, the OS automatically turns it into a crisp visible outline.