Instructions for best color practices

[jhauga]

Pull Request Checklist

• I have read and followed the CONTRIBUTING.md guidelines.
• My contribution adds a new instruction, prompt, or chat mode file in the correct directory.
• The file follows the required naming convention.
• The content is clearly structured and follows the example format.
• I have tested my instructions, prompt, or chat mode with GitHub Copilot.
• I have run npm start and verified that README.md is up to date.

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Description

Instructions to apply best website color practices.

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Type of Contribution

• New instruction file.
• New prompt file.
• New chat mode file.
• New collection file.
• New skill file.
• Update to existing instruction, prompt, chat mode, collection or skill.
• Other (please specify):

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By submitting this pull request, I confirm that my contribution abides by the Code of Conduct and will be licensed under the MIT License.

[Copilot]

Pull request overview

This pull request adds a new instruction file for HTML/CSS color usage guidelines to help ensure accessible and professional website designs. The instruction provides prescriptive guidance for color selection in web development contexts.

Changes:

• New instruction file for HTML/CSS color usage best practices
• README entry added for the new instruction file

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
instructions/html-css-style-color-guide.instructions.md	New instruction file defining color usage rules, the 60-30-10 rule, and recommendations for backgrounds, text, and gradients
docs/README.instructions.md	Added table entry for the new HTML CSS Style Color Guide instruction with installation badges