Enhance the look and feel of forms and data display for improved UI

Updates the styles of input fields, vendor sections, and filter cards to provide better visual consistency.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: dec54137-d5a2-4406-8ad4-5f2f9fb110bf
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/0715008c-7244-40f4-befc-26c014852236/19d76f99-63e3-4717-987b-4fafe960e234.jpg

client/src/components/NewSaleForm.tsx

@@ -168,7 +168,7 @@ export default function NewSaleForm() {
             {/* Seller Information */}
             <div className="modern-section modern-section-vendor">
               <div className="modern-section-header">
-                <div className="modern-icon-container">
+                <div className="w-10 h-10 bg-purple-500 text-white flex items-center justify-center border-2 border-purple-500 shadow-md">
                   <User className="h-5 w-5" />
                 </div>
                 <span className="truncate">Informations Vendeur</span>

client/src/components/SalesHistory.tsx

@@ -264,10 +264,10 @@ export default function SalesHistory({ canDelete = false }: SalesHistoryProps) {
       </CardHeader>
       <CardContent>
         {/* Filters */}
-        <div className="flex flex-col sm:flex-row gap-4 items-start sm:items-end modern-section">
+        <div className="flex flex-col sm:flex-row gap-4 items-start sm:items-end modern-filter-card">
           <div className="grid grid-cols-1 sm:grid-cols-2 gap-4 flex-1 w-full">
             <div>
-              <label className="font-medium">Date de début</label>
+              <label className="font-medium text-sm block mb-2">Date de début</label>
               <Input
                 type="date"
                 value={startDate}
@@ -276,7 +276,7 @@ export default function SalesHistory({ canDelete = false }: SalesHistoryProps) {
               />
             </div>
             <div>
-              <label className="font-medium">Date de fin</label>
+              <label className="font-medium text-sm block mb-2">Date de fin</label>
               <Input
                 type="date"
                 value={endDate}