feat: enhance Kanban components with new UI elements

- Added `ColumnHeader`, `EmptyState`, and `DropZone` components to improve the Kanban UI structure and user experience.
- Refactored `KanbanColumn` to utilize the new components, enhancing readability and maintainability.
- Updated `Card` component to support flexible props for shadow, border, and background, allowing for better customization across the application.
- Adjusted `SwimlanesBase` to incorporate the new `ColumnHeader` for consistent column representation.

src/components/kanban/Board.tsx

@@ -86,7 +86,7 @@ export function KanbanBoard({ tasks, onCreateTask, onEditTask, onUpdateStatus, c
       <div className="pt-4"></div>
 
         {/* Board tech dark */}
-        <div className="flex-1 flex gap-3 overflow-x-auto p-6">
+        <div className="flex-1 flex gap-3 overflow-x-auto p-6 min-w-0">
           {visibleColumns.map((column) => (
             <KanbanColumn
               key={column.id}

src/components/kanban/Column.tsx

@@ -1,12 +1,11 @@
 import { Task, TaskStatus } from '@/lib/types';
 import { TaskCard } from './TaskCard';
 import { QuickAddTask } from './QuickAddTask';
-import { Card, CardHeader, CardContent } from '@/components/ui/Card';
-import { Badge } from '@/components/ui/Badge';
+import { Card, CardHeader, CardContent, ColumnHeader, EmptyState, DropZone } from '@/components/ui';
 import { CreateTaskData } from '@/clients/tasks-client';
 import { useState } from 'react';
 import { useDroppable } from '@dnd-kit/core';
-import { getStatusConfig, getTechStyle, getBadgeVariant } from '@/lib/status-config';
+import { getStatusConfig, getTechStyle } from '@/lib/status-config';
 
 interface KanbanColumnProps {
   id: TaskStatus;
@@ -27,41 +26,23 @@ export function KanbanColumn({ id, tasks, onCreateTask, onEditTask, compactView
   // Récupération de la config du statut
   const statusConfig = getStatusConfig(id);
   const style = getTechStyle(statusConfig.color);
-  const badgeVariant = getBadgeVariant(statusConfig.color);
 
   return (
-    <div className="flex-shrink-0 w-80 md:w-1/4 md:flex-1 h-full">
-      <Card 
-        ref={setNodeRef}
-        variant="column" 
-        className={`h-full flex flex-col transition-all duration-200 ${
-          isOver ? 'ring-2 ring-[var(--primary)]/50 bg-[var(--card-hover)]' : ''
-        }`}
-      >
-        <CardHeader className="pb-4">
-          <div className="flex items-center justify-between">
-            <div className="flex items-center gap-3">
-              <div className={`w-2 h-2 rounded-full ${style.accent.replace('text-', 'bg-')} animate-pulse`}></div>
-              <h3 className={`font-mono text-sm font-bold ${style.accent} uppercase tracking-wider`}>
-                {statusConfig.label} {statusConfig.icon}
-              </h3>
-            </div>
-            <div className="flex items-center gap-2">
-              <Badge variant={badgeVariant} size="sm">
-                {String(tasks.length).padStart(2, '0')}
-              </Badge>
-              {onCreateTask && (
-                <button
-                  onClick={() => setShowQuickAdd(true)}
-                  className={`w-5 h-5 rounded-full border border-dashed ${style.border} ${style.accent} hover:bg-[var(--card-hover)] transition-colors flex items-center justify-center text-xs font-mono`}
-                  title="Ajouter une tâche rapide"
-                >
-                  +
-                </button>
-              )}
-            </div>
-          </div>
-        </CardHeader>
+    <div className="flex-shrink-0 w-72 md:w-72 lg:w-80 h-full">
+      <DropZone ref={setNodeRef} isOver={isOver}>
+        <Card variant="column" className="h-full flex flex-col">
+          <CardHeader className="pb-4">
+            <ColumnHeader
+              title={statusConfig.label}
+              icon={statusConfig.icon}
+              count={tasks.length}
+              color={style.accent.replace('text-', '')}
+              accentColor={style.accent}
+              borderColor={style.border}
+              showAddButton={!!onCreateTask}
+              onAddClick={() => setShowQuickAdd(true)}
+            />
+          </CardHeader>
 
         <CardContent className="flex-1 p-4 h-[calc(100vh-220px)] overflow-y-auto">
           <div className="space-y-3">
@@ -78,15 +59,11 @@ export function KanbanColumn({ id, tasks, onCreateTask, onEditTask, compactView
             )}
             
             {tasks.length === 0 && !showQuickAdd ? (
-              <div className="text-center py-20">
-                <div className={`w-16 h-16 mx-auto mb-4 rounded-full bg-[var(--card)] border-2 border-dashed ${style.border} flex items-center justify-center`}>
-                  <span className={`text-2xl ${style.accent} opacity-50`}>{statusConfig.icon}</span>
-                </div>
-                <p className="text-xs font-mono text-[var(--muted-foreground)] uppercase tracking-wide">NO DATA</p>
-                <div className="mt-2 flex justify-center">
-                  <div className={`w-8 h-0.5 ${style.accent.replace('text-', 'bg-')} opacity-30`}></div>
-                </div>
-              </div>
+              <EmptyState
+                icon={statusConfig.icon}
+                accentColor={style.accent}
+                borderColor={style.border}
+              />
             ) : (
               tasks.map((task) => (
                 <TaskCard key={task.id} task={task} onEdit={onEditTask} compactView={compactView} />
@@ -94,7 +71,8 @@ export function KanbanColumn({ id, tasks, onCreateTask, onEditTask, compactView
             )}
           </div>
         </CardContent>
-      </Card>
+        </Card>
+      </DropZone>
     </div>
   );
 }

src/components/kanban/SwimlanesBase.tsx

@@ -8,6 +8,7 @@ import { useState } from 'react';
 import { useUserPreferences } from '@/contexts/UserPreferencesContext';
 import { useDragAndDrop } from '@/hooks/useDragAndDrop';
 import { getAllStatuses, getTechStyle } from '@/lib/status-config';
+import { Card, CardHeader, ColumnHeader, DropZone } from '@/components/ui';
 import {
   DndContext,
   DragEndEvent,
@@ -49,7 +50,7 @@ function DroppableColumn({
   });
 
   return (
-    <div ref={setNodeRef} className="min-h-[100px] relative group/column">
+    <DropZone ref={setNodeRef} className="min-h-[100px] relative group/column">
       <SortableContext items={tasks.map(t => t.id)} strategy={verticalListSortingStrategy}>
         <div className="space-y-3">
           {tasks.map(task => (
@@ -90,7 +91,7 @@ function DroppableColumn({
           )}
         </>
       )}
-    </div>
+    </DropZone>
   );
 }
 
@@ -197,11 +198,18 @@ export function SwimlanesBase({
           {statusesToShow.map(status => {
             const statusConfig = allStatuses.find(s => s.key === status);
             const techStyle = statusConfig ? getTechStyle(statusConfig.color) : null;
+            const tasksInStatus = tasks.filter(task => task.status === status);
+            
             return (
               <div key={status} className="text-center">
-                <h3 className={`text-sm font-mono font-bold uppercase tracking-wider ${techStyle?.accent || 'text-[var(--foreground)]'}`}>
-                  {statusConfig?.icon} {statusConfig?.label}
-                </h3>
+                <ColumnHeader
+                  title={statusConfig?.label || status}
+                  icon={statusConfig?.icon}
+                  count={tasksInStatus.length}
+                  color={techStyle?.accent.replace('text-', '')}
+                  accentColor={techStyle?.accent}
+                  className="justify-center gap-4"
+                />
               </div>
             );
           })}
@@ -214,12 +222,12 @@ export function SwimlanesBase({
               const isCollapsed = collapsedSwimlanes.has(swimlane.key);
               
               return (
-                <div key={swimlane.key} className="border border-[var(--border)]/50 rounded-lg bg-[var(--card-column)]">
+                <Card key={swimlane.key} background="column" className="overflow-hidden">
                   {/* Header de la swimlane */}
-                  <div className="flex items-center p-2 border-b border-[var(--border)]/50">
+                  <CardHeader padding="sm" separator={false}>
                     <button
                       onClick={() => toggleSwimlane(swimlane.key)}
-                      className="flex items-center gap-2 hover:bg-[var(--card-hover)] rounded p-1 -m-1 transition-colors"
+                      className="flex items-center gap-2 hover:bg-[var(--card-hover)] rounded p-1 -m-1 transition-colors w-full"
                     >
                       <svg 
                         className={`w-4 h-4 text-[var(--muted-foreground)] transition-transform ${isCollapsed ? '' : 'rotate-90'}`}
@@ -240,7 +248,7 @@ export function SwimlanesBase({
                         {swimlane.label} ({swimlane.tasks.length})
                       </span>
                     </button>
-                  </div>
+                  </CardHeader>
 
                   {/* Contenu de la swimlane */}
                   {!isCollapsed && (
@@ -272,7 +280,7 @@ export function SwimlanesBase({
                       })}
                     </div>
                   )}
-                </div>
+                </Card>
               );
             })}
           </div>

src/components/ui-showcase/UIShowcaseClient.tsx

@@ -8,7 +8,7 @@ import { Alert, AlertTitle, AlertDescription } from '@/components/ui/Alert';
 import { Input } from '@/components/ui/Input';
 import { StyledCard } from '@/components/ui/StyledCard';
 import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/Card';
-import { StatCard, ProgressBar, ActionCard, TaskCard, MetricCard, ToggleButton, SearchInput, ControlPanel, ControlSection, ControlGroup, FilterSummary, FilterChip } from '@/components/ui';
+import { StatCard, ProgressBar, ActionCard, TaskCard, MetricCard, ToggleButton, SearchInput, ControlPanel, ControlSection, ControlGroup, FilterSummary, FilterChip, ColumnHeader, EmptyState, DropZone } from '@/components/ui';
 import { ThemeSelector } from '@/components/ThemeSelector';
 
 export function UIShowcaseClient() {
@@ -244,6 +244,54 @@ export function UIShowcaseClient() {
               </p>
             </StyledCard>
           </div>
+
+          {/* Nouveaux exemples avec props flexibles */}
+          <div className="space-y-4">
+            <h3 className="text-lg font-medium text-[var(--foreground)]">Card Flexible Props</h3>
+            <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-4">
+              <div className="space-y-2">
+                <div className="text-xs font-mono text-[var(--muted-foreground)] bg-[var(--card)] px-2 py-1 rounded">
+                  shadow="lg" border="primary"
+                </div>
+                <Card shadow="lg" border="primary">
+                  <CardHeader padding="sm">
+                    <CardTitle size="sm">Small Header</CardTitle>
+                  </CardHeader>
+                  <CardContent padding="sm">
+                    <p className="text-sm text-[var(--muted-foreground)]">Small padding content.</p>
+                  </CardContent>
+                </Card>
+              </div>
+
+              <div className="space-y-2">
+                <div className="text-xs font-mono text-[var(--muted-foreground)] bg-[var(--card)] px-2 py-1 rounded">
+                  background="column" shadow="md"
+                </div>
+                <Card background="column" shadow="md">
+                  <CardHeader separator={false}>
+                    <CardTitle size="lg">No Separator</CardTitle>
+                  </CardHeader>
+                  <CardContent padding="lg">
+                    <p className="text-sm text-[var(--muted-foreground)]">Large padding, no separator.</p>
+                  </CardContent>
+                </Card>
+              </div>
+
+              <div className="space-y-2">
+                <div className="text-xs font-mono text-[var(--muted-foreground)] bg-[var(--card)] px-2 py-1 rounded">
+                  border="none" shadow="none"
+                </div>
+                <Card border="none" shadow="none">
+                  <CardHeader padding="md">
+                    <CardTitle>Minimal Card</CardTitle>
+                  </CardHeader>
+                  <CardContent padding="none">
+                    <p className="text-sm text-[var(--muted-foreground)]">No border, no shadow, no padding.</p>
+                  </CardContent>
+                </Card>
+              </div>
+            </div>
+          </div>
         </section>
 
         {/* Interactive Demo */}
@@ -797,6 +845,62 @@ export function UIShowcaseClient() {
                  </div>
                </div>
              </div>
+
+             {/* Column Components */}
+             <div className="space-y-6">
+               <h3 className="text-lg font-medium text-[var(--foreground)]">Column Components</h3>
+               <div className="space-y-4">
+                 <div className="space-y-2">
+                   <div className="text-xs font-mono text-[var(--muted-foreground)] bg-[var(--card)] px-2 py-1 rounded">
+                     ColumnHeader - Header de colonne Kanban
+                   </div>
+                   <div className="max-w-md">
+                     <ColumnHeader
+                       title="En cours"
+                       icon="🔄"
+                       count={5}
+                       color="blue"
+                       accentColor="text-blue-500"
+                       borderColor="border-blue-300"
+                       showAddButton={true}
+                       onAddClick={() => console.log('Add task')}
+                     />
+                   </div>
+                 </div>
+
+                 <div className="space-y-2">
+                   <div className="text-xs font-mono text-[var(--muted-foreground)] bg-[var(--card)] px-2 py-1 rounded">
+                     EmptyState - État vide avec icône
+                   </div>
+                   <div className="max-w-md">
+                     <EmptyState
+                       icon="📋"
+                       title="NO DATA"
+                       accentColor="text-gray-500"
+                       borderColor="border-gray-300"
+                     />
+                   </div>
+                 </div>
+
+                 <div className="space-y-2">
+                   <div className="text-xs font-mono text-[var(--muted-foreground)] bg-[var(--card)] px-2 py-1 rounded">
+                     DropZone - Zone de drop avec animation
+                   </div>
+                   <div className="max-w-md">
+                     <DropZone isOver={false}>
+                       <div className="p-4 border border-[var(--border)] rounded-lg bg-[var(--card)]">
+                         <p className="text-sm text-[var(--muted-foreground)]">Zone de drop normale</p>
+                       </div>
+                     </DropZone>
+                     <DropZone isOver={true}>
+                       <div className="p-4 border border-[var(--border)] rounded-lg bg-[var(--card)]">
+                         <p className="text-sm text-[var(--muted-foreground)]">Zone de drop active (isOver=true)</p>
+                       </div>
+                     </DropZone>
+                   </div>
+                 </div>
+               </div>
+             </div>
         </section>
 
         {/* Footer */}

src/components/ui/Card.tsx

@@ -3,23 +3,54 @@ import { cn } from '@/lib/utils';
 
 interface CardProps extends HTMLAttributes<HTMLDivElement> {
   variant?: 'default' | 'elevated' | 'bordered' | 'column';
+  shadow?: 'none' | 'sm' | 'md' | 'lg';
+  border?: 'none' | 'default' | 'primary' | 'accent';
+  background?: 'default' | 'column' | 'muted';
 }
 
 const Card = forwardRef<HTMLDivElement, CardProps>(
-  ({ className, variant = 'default', ...props }, ref) => {
-    const variants = {
-      default: 'bg-[var(--card)]/50 border border-[var(--border)]/50',
-      elevated: 'bg-[var(--card)]/80 border border-[var(--border)]/50 shadow-lg shadow-[var(--card)]/20',
-      bordered: 'bg-[var(--card)]/50 border border-[var(--primary)]/30 shadow-[var(--primary)]/10 shadow-lg',
-      column: 'bg-[var(--card-column)] border border-[var(--border)]/50 shadow-lg shadow-[var(--card)]/20'
+  ({ className, variant = 'default', shadow = 'sm', border = 'default', background = 'default', ...props }, ref) => {
+    const backgrounds = {
+      default: 'bg-[var(--card)]',
+      column: 'bg-[var(--card-column)]',
+      muted: 'bg-[var(--muted)]/10'
     };
+
+    const borders = {
+      none: '',
+      default: 'border border-[var(--border)]',
+      primary: 'border border-[var(--primary)]/30',
+      accent: 'border border-[var(--accent)]/30'
+    };
+
+    const shadows = {
+      none: '',
+      sm: 'shadow-sm',
+      md: 'shadow-md',
+      lg: 'shadow-lg'
+    };
+
+    // Variants prédéfinis pour la rétrocompatibilité
+    const variantStyles = {
+      default: '',
+      elevated: 'shadow-lg',
+      bordered: 'border-[var(--primary)]/30 shadow-lg',
+      column: 'bg-[var(--card-column)] shadow-lg'
+    };
+
+    // Appliquer le variant si spécifié, sinon utiliser les props individuelles
+    const finalShadow = variant !== 'default' ? variantStyles[variant] : shadows[shadow];
+    const finalBorder = variant !== 'default' ? variantStyles[variant] : borders[border];
+    const finalBackground = variant !== 'default' ? variantStyles[variant] : backgrounds[background];
     
     return (
       <div
         ref={ref}
         className={cn(
           'rounded-lg backdrop-blur-sm transition-all duration-200',
-          variants[variant],
+          finalBackground,
+          finalBorder,
+          finalShadow,
           className
         )}
         {...props}
@@ -30,50 +61,113 @@ const Card = forwardRef<HTMLDivElement, CardProps>(
 
 Card.displayName = 'Card';
 
-const CardHeader = forwardRef<HTMLDivElement, HTMLAttributes<HTMLDivElement>>(
-  ({ className, ...props }, ref) => (
-    <div
-      ref={ref}
-      className={cn('p-4 border-b border-[var(--border)]/50', className)}
-      {...props}
-    />
-  )
+interface CardHeaderProps extends HTMLAttributes<HTMLDivElement> {
+  separator?: boolean;
+  padding?: 'sm' | 'md' | 'lg';
+}
+
+const CardHeader = forwardRef<HTMLDivElement, CardHeaderProps>(
+  ({ className, separator = true, padding = 'md', ...props }, ref) => {
+    const paddings = {
+      sm: 'p-2',
+      md: 'p-4',
+      lg: 'p-6'
+    };
+
+    return (
+      <div
+        ref={ref}
+        className={cn(
+          paddings[padding],
+          separator && 'border-b border-[var(--border)]',
+          className
+        )}
+        {...props}
+      />
+    );
+  }
 );
 
 CardHeader.displayName = 'CardHeader';
 
-const CardTitle = forwardRef<HTMLHeadingElement, HTMLAttributes<HTMLHeadingElement>>(
-  ({ className, ...props }, ref) => (
-    <h3
-      ref={ref}
-      className={cn('font-mono font-semibold text-[var(--foreground)] tracking-wide', className)}
-      {...props}
-    />
-  )
+interface CardTitleProps extends HTMLAttributes<HTMLHeadingElement> {
+  size?: 'sm' | 'md' | 'lg';
+}
+
+const CardTitle = forwardRef<HTMLHeadingElement, CardTitleProps>(
+  ({ className, size = 'md', ...props }, ref) => {
+    const sizes = {
+      sm: 'text-sm',
+      md: 'text-base',
+      lg: 'text-lg'
+    };
+
+    return (
+      <h3
+        ref={ref}
+        className={cn(
+          'font-mono font-semibold text-[var(--foreground)] tracking-wide',
+          sizes[size],
+          className
+        )}
+        {...props}
+      />
+    );
+  }
 );
 
 CardTitle.displayName = 'CardTitle';
 
-const CardContent = forwardRef<HTMLDivElement, HTMLAttributes<HTMLDivElement>>(
-  ({ className, ...props }, ref) => (
-    <div
-      ref={ref}
-      className={cn('p-4', className)}
-      {...props}
-    />
-  )
+interface CardContentProps extends HTMLAttributes<HTMLDivElement> {
+  padding?: 'sm' | 'md' | 'lg' | 'none';
+}
+
+const CardContent = forwardRef<HTMLDivElement, CardContentProps>(
+  ({ className, padding = 'md', ...props }, ref) => {
+    const paddings = {
+      none: '',
+      sm: 'p-2',
+      md: 'p-4',
+      lg: 'p-6'
+    };
+
+    return (
+      <div
+        ref={ref}
+        className={cn(paddings[padding], className)}
+        {...props}
+      />
+    );
+  }
 );
 
 CardContent.displayName = 'CardContent';
 
-const CardFooter = forwardRef<HTMLDivElement, HTMLAttributes<HTMLDivElement>>(
-  ({ className, ...props }, ref) => (
-    <div
-      ref={ref}
-      className={cn('p-4 border-t border-[var(--border)]/50', className)}
-      {...props}
-    />
-  )
+interface CardFooterProps extends HTMLAttributes<HTMLDivElement> {
+  separator?: boolean;
+  padding?: 'sm' | 'md' | 'lg';
+}
+
+const CardFooter = forwardRef<HTMLDivElement, CardFooterProps>(
+  ({ className, separator = true, padding = 'md', ...props }, ref) => {
+    const paddings = {
+      sm: 'p-2',
+      md: 'p-4',
+      lg: 'p-6'
+    };
+
+    return (
+      <div
+        ref={ref}
+        className={cn(
+          paddings[padding],
+          separator && 'border-t border-[var(--border)]',
+          className
+        )}
+        {...props}
+      />
+    );
+  }
 );
 
 CardFooter.displayName = 'CardFooter';

src/components/ui/ColumnHeader.tsx

@@ -0,0 +1,77 @@
+import { HTMLAttributes, forwardRef } from 'react';
+import { cn } from '@/lib/utils';
+import { Badge } from './Badge';
+
+interface ColumnHeaderProps extends HTMLAttributes<HTMLDivElement> {
+  title: string;
+  icon?: string;
+  count: number;
+  color?: string;
+  accentColor?: string;
+  borderColor?: string;
+  onAddClick?: () => void;
+  showAddButton?: boolean;
+}
+
+const ColumnHeader = forwardRef<HTMLDivElement, ColumnHeaderProps>(
+  ({ 
+    className, 
+    title, 
+    icon, 
+    count, 
+    color, 
+    accentColor, 
+    borderColor, 
+    onAddClick, 
+    showAddButton = false,
+    ...props 
+  }, ref) => {
+    return (
+      <div
+        ref={ref}
+        className={cn("flex items-center justify-between", className)}
+        {...props}
+      >
+        <div className="flex items-center gap-3">
+          <div 
+            className={cn(
+              "w-2 h-2 rounded-full animate-pulse",
+              color ? `bg-${color}` : "bg-[var(--primary)]"
+            )}
+          />
+          <h3 
+            className={cn(
+              "font-mono text-sm font-bold uppercase tracking-wider",
+              accentColor || "text-[var(--foreground)]"
+            )}
+          >
+            {title} {icon}
+          </h3>
+        </div>
+        
+        <div className="flex items-center gap-2">
+          <Badge variant="default" size="sm">
+            {String(count).padStart(2, '0')}
+          </Badge>
+          {showAddButton && onAddClick && (
+            <button
+              onClick={onAddClick}
+              className={cn(
+                "w-5 h-5 rounded-full border border-dashed hover:bg-[var(--card-hover)] transition-colors flex items-center justify-center text-xs font-mono",
+                borderColor || "border-[var(--border)]",
+                accentColor || "text-[var(--muted-foreground)]"
+              )}
+              title="Ajouter une tâche rapide"
+            >
+              +
+            </button>
+          )}
+        </div>
+      </div>
+    );
+  }
+);
+
+ColumnHeader.displayName = 'ColumnHeader';
+
+export { ColumnHeader };

src/components/ui/DropZone.tsx

@@ -0,0 +1,31 @@
+import { HTMLAttributes, forwardRef } from 'react';
+import { cn } from '@/lib/utils';
+
+interface DropZoneProps extends HTMLAttributes<HTMLDivElement> {
+  isOver?: boolean;
+  children: React.ReactNode;
+}
+
+const DropZone = forwardRef<HTMLDivElement, DropZoneProps>(
+  ({ className, isOver = false, children, ...props }, ref) => {
+    return (
+      <div
+        ref={ref}
+        className={cn(
+          "transition-all duration-200",
+          isOver 
+            ? "ring-2 ring-[var(--primary)]/50 bg-[var(--card-hover)]" 
+            : "",
+          className
+        )}
+        {...props}
+      >
+        {children}
+      </div>
+    );
+  }
+);
+
+DropZone.displayName = 'DropZone';
+
+export { DropZone };

src/components/ui/EmptyState.tsx

@@ -0,0 +1,107 @@
+import { HTMLAttributes, forwardRef } from 'react';
+import { cn } from '@/lib/utils';
+
+interface EmptyStateProps extends HTMLAttributes<HTMLDivElement> {
+  icon?: string;
+  title?: string;
+  description?: string;
+  accentColor?: string;
+  borderColor?: string;
+  size?: 'sm' | 'md' | 'lg';
+}
+
+const EmptyState = forwardRef<HTMLDivElement, EmptyStateProps>(
+  ({ 
+    className, 
+    icon, 
+    title = "NO DATA", 
+    description,
+    accentColor, 
+    borderColor,
+    size = 'md',
+    ...props 
+  }, ref) => {
+    const sizes = {
+      sm: {
+        container: 'py-8',
+        icon: 'w-8 h-8 text-lg',
+        title: 'text-xs',
+        divider: 'w-4 h-0.5'
+      },
+      md: {
+        container: 'py-20',
+        icon: 'w-16 h-16 text-2xl',
+        title: 'text-xs',
+        divider: 'w-8 h-0.5'
+      },
+      lg: {
+        container: 'py-32',
+        icon: 'w-24 h-24 text-3xl',
+        title: 'text-sm',
+        divider: 'w-12 h-0.5'
+      }
+    };
+
+    const currentSize = sizes[size];
+
+    return (
+      <div
+        ref={ref}
+        className={cn("text-center", currentSize.container, className)}
+        {...props}
+      >
+        <div 
+          className={cn(
+            "mx-auto mb-4 rounded-full bg-[var(--card)] border-2 border-dashed flex items-center justify-center",
+            currentSize.icon,
+            borderColor || "border-[var(--border)]"
+          )}
+        >
+          <span 
+            className={cn(
+              "opacity-50",
+              accentColor || "text-[var(--muted-foreground)]"
+            )}
+          >
+            {icon || "📋"}
+          </span>
+        </div>
+        
+        <p 
+          className={cn(
+            "font-mono uppercase tracking-wide",
+            currentSize.title,
+            accentColor || "text-[var(--muted-foreground)]"
+          )}
+        >
+          {title}
+        </p>
+        
+        {description && (
+          <p 
+            className={cn(
+              "mt-2 text-xs text-[var(--muted-foreground)]",
+              accentColor || "text-[var(--muted-foreground)]"
+            )}
+          >
+            {description}
+          </p>
+        )}
+        
+        <div className="mt-2 flex justify-center">
+          <div 
+            className={cn(
+              "opacity-30",
+              currentSize.divider,
+              accentColor ? accentColor.replace('text-', 'bg-') : "bg-[var(--muted-foreground)]"
+            )}
+          />
+        </div>
+      </div>
+    );
+  }
+);
+
+EmptyState.displayName = 'EmptyState';
+
+export { EmptyState };

src/components/ui/index.ts

@@ -18,6 +18,9 @@ export { SearchInput } from './SearchInput';
 export { ControlPanel, ControlSection, ControlGroup } from './ControlPanel';
 export { FilterSummary } from './FilterSummary';
 export { FilterChip } from './FilterChip';
+export { ColumnHeader } from './ColumnHeader';
+export { EmptyState } from './EmptyState';
+export { DropZone } from './DropZone';
 
 // Composants existants
 export { Card, CardHeader, CardTitle, CardContent, CardFooter } from './Card';