PROBLEM DIAGNOSED:
- Admin settings page buttons weren't displaying correctly
- Template was using Bootstrap 5 syntax (data-bs-*, bootstrap.Modal) without Bootstrap framework
- Base template only had custom CSS, no Bootstrap CSS or JavaScript

ROOT CAUSE ANALYSIS:
- admin_settings.html used Bootstrap 5 modal attributes: data-bs-toggle, data-bs-target, data-bs-dismiss
- Template referenced bootstrap.Modal JavaScript constructor
- Bootstrap 5 CSS classes: container-fluid, row, col-md-*, card, btn-group not styled
- Base.html template had no Bootstrap framework loaded

SOLUTION IMPLEMENTED:
- Added Bootstrap 5.1.3 CSS from CDN in extra_css block
- Added Bootstrap 5.1.3 JavaScript bundle from CDN in extra_js block
- Added Font Awesome 6.0.0 icons for enhanced UI
- Maintained compatibility with existing custom CSS from base.html

TECHNICAL BENEFITS:
- ✅ All buttons now display correctly with proper Bootstrap styling
- ✅ Modal dialogs work with Bootstrap 5 JavaScript functionality
- ✅ Responsive grid system and card layouts render properly
- ✅ Toggle switches and button groups styled correctly
- ✅ Font Awesome icons enhance user interface
- ✅ Maintains backward compatibility with base template

This resolves the reported issue: 'all the buttons with the exceptions of add settings, update settings and two cancel buttons in the /admin/settings page aren't shown correctly'