🎨 Palette: Add :active states to buttons and social cards

[keough99]

💡 What: Added complementary :active CSS states to .btn and .social-card elements to accompany their existing :hover states.
🎯 Why: To improve micro-UX by providing continuous, satisfying tactile feedback when a user clicks or taps an interactive element.
📸 Before/After: Visual feedback is now more responsive during the active click state (scaling down .btn to 0.98, and reducing .social-card upward translation).
♿ Accessibility: Enhances tactile visual feedback for pointer interactions.

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PR created automatically by Jules for task 11750354766303722824 started by @keough99

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