refactor: update class names for consistency and improve styling

- Changed `flex-shrink-0` to `shrink-0` in multiple components for better consistency.
- Updated button and checkbox classes to use `rounded-sm` for a more uniform appearance.
- Adjusted backdrop blur classes for modals to `backdrop-blur-xs` for a subtler effect.
- Removed unused Tailwind CSS configuration file.

src/components/Modal.jsx

@@ -3,7 +3,7 @@ import { X } from 'lucide-react';
 export default function Modal({ title, children, onClose, maxWidth = 'max-w-lg' }) {
   return (
     <div className="fixed inset-0 z-50 flex items-center justify-center p-4">
-      <div className="fixed inset-0 bg-black/60 backdrop-blur-sm" onClick={onClose} />
+      <div className="fixed inset-0 bg-black/60 backdrop-blur-xs" onClick={onClose} />
       <div className={`relative bg-th-card rounded-2xl border border-th-border shadow-2xl w-full ${maxWidth}`}>
         {/* Header */}
         <div className="flex items-center justify-between px-6 py-4 border-b border-th-border rounded-t-2xl">