If you open any massive legacy codebase or inspect a fresh Figma handoff, you will probably see one hex code repeating everywhere: #d9d9d9.

It’s the ultimate default. Developers use it for disabled buttons, subtle borders, card backgrounds, and dividers. But treating this specific light gray as a "safe" neutral is causing massive UI bugs in your production apps right now.

Here is why you need to stop hardcoding #d9d9d9 and how to handle it properly.

The Dark Mode Theme Breaker

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