🎨 Palette: Add active states to buttons and social cards

[keough99]

💡 What: Added :active states for .btn and .social-card elements.
🎯 Why: Pairs transform-based CSS :hover states with a complementary :active state to provide continuous, satisfying tactile feedback during interactions.
📸 Before/After: Verified via Playwright screenshots and video.
♿ Accessibility: Enhances tactile interaction feedback for users.

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PR created automatically by Jules for task 6582214526184478344 started by @keough99

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