梁建民 / scm_app

- Replace static gradient background with layered button structure for advanced animations
- Add particle burst effect on button click with staggered animation delays
- Implement gradient shift animation on button background using keyframes
- Add loading state with pulsing animation and spinner dots with wave effect
- Add success state with pop animation and text bounce effect
- Refactor button pseudo-elements into nested components (.btn-bg, .btn-particles, .btn-content)
- Update transition timing to use cubic-bezier easing for smoother motion
- Add loading spinner with three animated dots replacing previous icon approach
- Improve visual feedback with scale transforms on active and loading states
- Enhance accessibility by preventing interactions during loading state