[Bug] Fix color parsing

[dfop02]

Description

Problem

Border styles using rgb() or rgba() with spaces (e.g. rgb(222, 222, 222)) were not parsed correctly because the parser splits values by spaces, breaking the color into invalid parts.

Solution

Normalize rgb()/rgba() values by removing internal spaces before parsing, allowing them to be handled correctly by the existing logic.

Impact

• Fixes incorrect border color rendering for RGB/RGBA values
• Keeps parsing logic simple and performant
• No changes to existing behavior outside this case

Issue Reference

Fixes #73

Checklist Before Requesting a Review

• I have performed a self-review of my code.
• My code follows the project's coding style and guidelines.
• I have run tests and verified that all existing and new tests pass.
• I have added new tests to cover my changes.