Just a heads up that HTML has native colour pickers: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/in...
Pros:
- 0 bytes to download.
- No js required.
- Familiar to your users.
- Allows using an "eye dropper" to pick any colour from the screen on most platforms.
- Allows user to save/recall their favourite colours or schemes (on some platforms).
- Localized.