fix two CSS rules that were overridden in hyperparam and demos

[severo]

No description provided.

[Copilot]

Pull Request Overview

This PR fixes CSS rule conflicts by improving specificity for table styling rules. The changes address issues where certain styles were being overridden in hyperparam and demo contexts.

• Improved CSS selector specificity to prevent style overrides
• Added new CSS variable for row number hover border color
• Restructured hover selectors to use nested syntax

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[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 2 comments.

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