Horizontalen Scroll verhindern: Lange Task-Titel werden überall abgeschnitten

- Globales overflow-x: hidden auf html/body/#root in index.css
- App.tsx: overflow-x-hidden und min-w-0 auf Hauptcontainer
- TaskCard: Eltern-Task-Titel mit truncate/min-w-0 im Flex-Layout
- KanbanBoard: min-w-0 overflow-hidden auf Spalten-Cards
- FiveMinuteStarter: truncate auf Task-Titel
- HyperfocusGuard: truncate auf Task-Buttons
- TaskBreakdownModal: truncate auf Task- und Subtask-Titel
- NotificationsPage: truncate + min-w-0 auf Benachrichtigungs-Titel

client/src/App.tsx

@@ -349,7 +349,7 @@ function AppContent() {
       <SidebarProvider>
         <AppSidebar user={user} />
         <SidebarInset>
-          <div className={`min-h-screen bg-background flex flex-col ${adhdEnabled ? 'adhd-mode' : ''} ${adhdEnabled && adhdSettings.reducedAnimations ? 'reduced-motion' : ''} ${adhdEnabled && adhdSettings.largerTargets ? 'larger-targets' : ''}`}>
+          <div className={`min-h-screen bg-background flex flex-col min-w-0 overflow-x-hidden ${adhdEnabled ? 'adhd-mode' : ''} ${adhdEnabled && adhdSettings.reducedAnimations ? 'reduced-motion' : ''} ${adhdEnabled && adhdSettings.largerTargets ? 'larger-targets' : ''}`}>
             {/* Mobile Header with Sidebar Toggle */}
             <header className="sticky top-0 z-50 flex items-center gap-3 px-4 py-3 bg-background/80 backdrop-blur-xl border-b border-border/50 md:hidden">
               <SidebarTrigger className="h-9 w-9" />
@@ -360,7 +360,7 @@ function AppContent() {
                 <span className="font-bold text-lg">{t('app.title')}</span>
               </div>
             </header>
-            <main className="flex-1 p-4 md:p-6 max-w-screen-2xl mx-auto w-full relative">
+            <main className="flex-1 p-4 md:p-6 max-w-screen-2xl mx-auto w-full relative overflow-x-hidden">
               <Switch>
                 <Route path="/">
                   <FocusMode

client/src/components/KanbanBoard.tsx

@@ -430,7 +430,7 @@ export default function KanbanBoard({ tasks, onTaskStatusChange, onTaskUpdate, o
               return (
                 <Card
                   key={column.id}
-                  className="p-3 sm:p-4"
+                  className="p-3 sm:p-4 min-w-0 overflow-hidden"
                   onDragOver={handleDragOver}
                   onDrop={() => handleDrop(column.status)}
                   data-testid={`column-${column.id}`}
@@ -494,7 +494,7 @@ export default function KanbanBoard({ tasks, onTaskStatusChange, onTaskUpdate, o
               return (
                 <Card
                   key={column.id}
-                  className="p-3 sm:p-4"
+                  className="p-3 sm:p-4 min-w-0 overflow-hidden"
                   onDragOver={handleDragOver}
                   onDrop={() => handleDrop(column.status)}
                   data-testid={`column-${column.id}`}
@@ -558,7 +558,7 @@ export default function KanbanBoard({ tasks, onTaskStatusChange, onTaskUpdate, o
               return (
                 <Card
                   key={column.id}
-                  className="p-3 sm:p-4"
+                  className="p-3 sm:p-4 min-w-0 overflow-hidden"
                   onDragOver={handleDragOver}
                   onDrop={() => handleDrop(column.status)}
                   data-testid={`column-${column.id}`}

client/src/components/TaskCard.tsx

@@ -351,10 +351,10 @@ export default function TaskCard({ task, onStartTimer, onStopTimer, onEdit, onDe
                 {/* Parent Task Link rendered in title now */}
                 <h3 className={`font-medium text-sm leading-tight truncate ${task.status === 'done' ? 'line-through' : ''}`} data-testid={`text-task-title-${task.id}`}>
                   {parentTask ? (
-                    <span className="flex items-center gap-1">
-                      <span className="text-muted-foreground font-normal">{parentTask.title}</span>
-                      <span className="text-muted-foreground">›</span>
-                      <span>{task.title}</span>
+                    <span className="flex items-center gap-1 min-w-0">
+                      <span className="text-muted-foreground font-normal truncate shrink">{parentTask.title}</span>
+                      <span className="text-muted-foreground shrink-0">›</span>
+                      <span className="truncate shrink">{task.title}</span>
                     </span>
                   ) : (
                     task.title

client/src/components/adhd/ai/TaskBreakdownModal.tsx

@@ -125,7 +125,7 @@ export function TaskBreakdownModal({ task, open, onOpenChange }: TaskBreakdownMo
 
         {/* Task info */}
         <div className="bg-muted/50 rounded-lg p-4 mb-4">
-          <h4 className="font-medium mb-1">{task.title}</h4>
+          <h4 className="font-medium mb-1 truncate">{task.title}</h4>
           {task.description && (
             <p className="text-sm text-muted-foreground">{task.description}</p>
           )}
@@ -195,8 +195,8 @@ export function TaskBreakdownModal({ task, open, onOpenChange }: TaskBreakdownMo
                       onCheckedChange={() => handleToggleSubtask(index)}
                       className="mt-0.5"
                     />
-                    <div className="flex-1">
-                      <p className="font-medium text-sm">{subtask.title}</p>
+                    <div className="flex-1 min-w-0">
+                      <p className="font-medium text-sm truncate">{subtask.title}</p>
                       <div className="flex items-center gap-1 mt-1 text-xs text-muted-foreground">
                         <Clock className="h-3 w-3" />
                         <span>~{subtask.estimatedMinutes} min</span>

client/src/components/adhd/focus/FiveMinuteStarter.tsx

@@ -117,7 +117,7 @@ export function FiveMinuteStarter({
               <h3 className="text-xl font-bold mb-2">
                 {t('adhd.fiveMin.title')}
               </h3>
-              <p className="text-muted-foreground mb-2">
+              <p className="text-muted-foreground mb-2 truncate max-w-full">
                 {task.title}
               </p>
               <p className="text-sm text-muted-foreground mb-6">

client/src/components/adhd/focus/HyperfocusGuard.tsx

@@ -147,6 +147,7 @@ export function HyperfocusGuard({ activeTaskId, onTaskStart }: HyperfocusGuardPr
                     hover:bg-amber-200 dark:hover:bg-amber-900
                     transition-colors text-sm
                     text-amber-900 dark:text-amber-100
+                    truncate
                   `}
                 >
                   {task.title}

client/src/index.css

@@ -2,6 +2,12 @@
 @tailwind components;
 @tailwind utilities;
 
+/* Prevent horizontal scroll globally */
+html, body, #root {
+  overflow-x: hidden;
+  max-width: 100vw;
+}
+
 /* LIGHT MODE */
 :root {
   --button-outline: rgba(0,0,0, .10);

client/src/pages/NotificationsPage.tsx

@@ -110,9 +110,9 @@ export default function NotificationsPage() {
                                 <div className={`p-2 rounded-full shrink-0 ${notif.type === 'overdue' ? 'bg-red-100 text-red-600 dark:bg-red-900/30 dark:text-red-400' : 'bg-blue-100 text-blue-600 dark:bg-blue-900/30 dark:text-blue-400'}`}>
                                     {notif.type === 'overdue' ? <AlertCircle className="h-5 w-5" /> : <Calendar className="h-5 w-5" />}
                                 </div>
-                                <div className="flex-1">
-                                    <div className="flex items-center justify-between">
-                                        <h3 className="font-semibold">{notif.task.title}</h3>
+                                <div className="flex-1 min-w-0">
+                                    <div className="flex items-center justify-between gap-2">
+                                        <h3 className="font-semibold truncate">{notif.task.title}</h3>
                                         <span className="text-xs text-muted-foreground whitespace-nowrap">
                                             {formatDistanceToNow(notif.timestamp, { addSuffix: true, locale: i18n.language === 'de' ? de : enUS })}
                                         </span>