Improve UI/UX, make responsive, polish buttons and layout

[ghanshyam2005singh]

Description:

The current UI for DevVerify works but needs visual improvements for a more professional and polished feel.

We should:

✅ Make the layout fully responsive on all screen sizes (mobile, tablet, desktop)
✅ Improve input and button styling (hover, focus, disabled states)
✅ Refine spacing, padding, and alignment between sections
✅ Add smooth transitions (e.g., when toggling dark mode or verifying certificate)
✅ Make the navbar sticky or fixed for better navigation
✅ Improve contrast and accessibility (check text colors, button sizes)
✅ Add loading spinners or indicators when submitting forms
✅ Add icons or visual cues (e.g., checkmark after successful verification)

---

Checklist:

• Improve form input fields (rounded, focus ring, better placeholder text)
• Update buttons with hover and disabled styles
• Make layout responsive with Tailwind breakpoints (sm, md, lg)
• Add loading spinner to Verify button
• Make navbar fixed at top with shadow
• Add small animations or transitions
• Check dark mode colors and polish
• Add helpful messages (e.g., “Invalid code” or “Code verified successfully”)

---

Optional enhancements:

• Add toast notifications (using react-hot-toast or similar)
• Replace raw links with React Router Link components
• Add smooth scroll to About/Contact sections

---

Priority: ⭐ High
Labels: enhancement ui/ux responsive
Assignee: open