diff --git a/package.json b/package.json
index 78ea268..0e5c991 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "my-weekly-todo-list",
-  "version": "1.55.1",
+  "version": "1.55.2",
   "description": "A web-based weekly task management application that organizes to-dos and calendar events in a single, intuitive weekly view",
   "main": "index.js",
   "scripts": {
diff --git a/src/app/globals.css b/src/app/globals.css
index b7e7484..6029a7f 100644
--- a/src/app/globals.css
+++ b/src/app/globals.css
@@ -1952,6 +1952,73 @@ h3 {
 }
 
 /* Kanban stage color indicator on weekly tasks */
+.kanban-card-subtask-toggle {
+  margin-top: 4px;
+}
+.kanban-card-subtask-btn {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  background: none;
+  border: none;
+  cursor: pointer;
+  padding: 3px 0;
+  color: var(--weekly-text-muted, #9ca3af);
+  font-size: 0.7rem;
+  font-weight: 600;
+  width: 100%;
+}
+.kanban-card-subtask-btn:hover {
+  color: var(--weekly-text, #666);
+}
+.kanban-card-subtask-bar {
+  flex: 1;
+  height: 4px;
+  border-radius: 2px;
+  background: var(--weekly-border, #e5e7eb);
+  position: relative;
+  overflow: hidden;
+  max-width: 60px;
+}
+.kanban-card-subtask-bar-fill {
+  position: absolute;
+  left: 0;
+  top: 0;
+  height: 100%;
+  border-radius: 2px;
+  transition: width 0.3s ease;
+}
+.kanban-card-subtask-count {
+  font-size: 0.7rem;
+  opacity: 0.8;
+}
+.kanban-card-subtask-list {
+  display: flex;
+  flex-direction: column;
+  gap: 2px;
+  padding: 4px 0 2px 2px;
+}
+.kanban-card-subtask-item {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  font-size: 0.75rem;
+  color: var(--weekly-text, #333);
+  padding: 1px 0;
+}
+.kanban-card-subtask-item input[type="checkbox"] {
+  width: 13px;
+  height: 13px;
+  cursor: pointer;
+  flex-shrink: 0;
+}
+.kanban-card-subtask-item.completed {
+  opacity: 0.5;
+}
+.kanban-card-subtask-done {
+  text-decoration: line-through;
+}
+
 .kanban-stage-indicator {
   width: 4px;
   border-radius: 2px;
diff --git a/src/components/WeeklyView.tsx b/src/components/WeeklyView.tsx
index df07317..da371c6 100644
--- a/src/components/WeeklyView.tsx
+++ b/src/components/WeeklyView.tsx
@@ -2078,6 +2078,7 @@ export default function WeeklyView() {
     const [kanbanAddingStageId, setKanbanAddingStageId] = useState<string | null>(null);
     const [kanbanNewTaskTitle, setKanbanNewTaskTitle] = useState("");
     const [kanbanDetailTask, setKanbanDetailTask] = useState<Task | null>(null);
+    const [kanbanExpandedCards, setKanbanExpandedCards] = useState<Set<string>>(new Set());
 
     const [protectEventTimes, setProtectEventTimes] = useState(false);
     const [unlockedEvents, setUnlockedEvents] = useState<Set<string>>(new Set());
@@ -6447,7 +6448,15 @@ export default function WeeklyView() {
                     return true;
                 });
 
-                const renderKanbanCard = (task: Task) => (
+                const renderKanbanCard = (task: Task) => {
+                    const subTasks = task.subTasks || [];
+                    const subCompleted = subTasks.filter(s => s.completed).length;
+                    const subTotal = subTasks.length;
+                    const subPct = subTotal > 0 ? (subCompleted / subTotal) * 100 : 0;
+                    const allSubDone = subTotal > 0 && subCompleted === subTotal;
+                    const isExpanded = kanbanExpandedCards.has(task.id);
+
+                    return (
                     <div
                         key={task.id}
                         className={`kanban-card ${task.completed ? "kanban-card-done" : ""}`}
@@ -6457,9 +6466,8 @@ export default function WeeklyView() {
                             e.dataTransfer.effectAllowed = "move";
                         }}
                         onClick={(e) => {
-                            // Don't open detail if clicking checkbox, contentEditable, or buttons
                             const target = e.target as HTMLElement;
-                            if (target.tagName === "INPUT" || target.contentEditable === "true" || target.closest("button")) return;
+                            if (target.tagName === "INPUT" || target.contentEditable === "true" || target.closest("button") || target.closest(".kanban-card-subtask-list")) return;
                             setKanbanDetailTask(task);
                         }}
                         style={{ cursor: "pointer" }}
@@ -6488,9 +6496,42 @@ export default function WeeklyView() {
                                 {task.title}
                             </span>
                         </div>
-                        {task.subTasks && task.subTasks.length > 0 && (
-                            <div className="kanban-card-subtasks" style={{ fontSize: "0.7rem", color: "#9ca3af", marginTop: "2px" }}>
-                                {task.subTasks.filter(st => st.completed).length}/{task.subTasks.length} {language === "de" ? "Unteraufgaben" : "subtasks"}
+                        {subTotal > 0 && (
+                            <div className="kanban-card-subtask-toggle" onClick={(e) => e.stopPropagation()}>
+                                <button
+                                    className="kanban-card-subtask-btn"
+                                    onClick={() => {
+                                        setKanbanExpandedCards(prev => {
+                                            const next = new Set(prev);
+                                            if (next.has(task.id)) next.delete(task.id);
+                                            else next.add(task.id);
+                                            return next;
+                                        });
+                                    }}
+                                >
+                                    <ChevronDown size={12} style={{ transform: isExpanded ? "rotate(0deg)" : "rotate(-90deg)", transition: "transform 0.2s" }} />
+                                    <span className="kanban-card-subtask-bar">
+                                        <span className="kanban-card-subtask-bar-fill" style={{ width: `${subPct}%`, background: allSubDone ? "#0d9488" : "var(--weekly-accent, #6366f1)" }} />
+                                    </span>
+                                    <span className="kanban-card-subtask-count" style={{ color: allSubDone ? "#0d9488" : undefined }}>
+                                        {subCompleted}/{subTotal}
+                                    </span>
+                                </button>
+                                {isExpanded && (
+                                    <div className="kanban-card-subtask-list">
+                                        {subTasks.map(sub => (
+                                            <div key={sub.id} className={`kanban-card-subtask-item ${sub.completed ? "completed" : ""}`}>
+                                                <input
+                                                    type="checkbox"
+                                                    checked={sub.completed}
+                                                    onChange={() => toggleSubTask(sub.id)}
+                                                    style={{ accentColor: "var(--weekly-accent, #6366f1)" }}
+                                                />
+                                                <span className={sub.completed ? "kanban-card-subtask-done" : ""}>{sub.title}</span>
+                                            </div>
+                                        ))}
+                                    </div>
+                                )}
                             </div>
                         )}
                         {task.markdownContent && (
@@ -6514,7 +6555,8 @@ export default function WeeklyView() {
                             return list ? <div className="kanban-card-list">{list.title}</div> : null;
                         })()}
                     </div>
-                );
+                    );
+                };
 
                 const kanbanColumnDrop = (stageId: string | null) => ({
                     onDragOver: (e: React.DragEvent) => {
@@ -9710,9 +9752,9 @@ function TaskItem({
                                             display: "inline-flex",
                                             alignItems: "center",
                                             gap: "4px",
-                                            padding: "2px 8px 2px 6px",
+                                            padding: "2px 8px 2px 4px",
                                             borderRadius: "12px",
-                                            background: "transparent",
+                                            background: expanded ? "rgba(99,102,241,0.08)" : "transparent",
                                             color: allDone ? "var(--weekly-teal, #0d9488)" : "var(--weekly-text-light, #9ca3af)",
                                             border: "none",
                                             cursor: "pointer",
@@ -9721,17 +9763,14 @@ function TaskItem({
                                             lineHeight: 1,
                                             flexShrink: 0,
                                             whiteSpace: "nowrap",
-                                            transition: "color 0.15s",
+                                            transition: "all 0.15s",
                                         }}
                                     >
-                                        <svg viewBox="0 0 24 24" width="10" height="10" fill="none" stroke="currentColor" strokeWidth="2.5" strokeLinecap="round" strokeLinejoin="round" style={{ transform: expanded ? "rotate(90deg)" : "rotate(0deg)", transition: "transform 0.2s" }}>
-                                            <polyline points="9 18 15 12 9 6" />
-                                        </svg>
-                                        {/* Mini progress bar */}
+                                        <ChevronDown size={11} style={{ transform: expanded ? "rotate(0deg)" : "rotate(-90deg)", transition: "transform 0.2s" }} />
                                         <span style={{
                                             display: "inline-block",
-                                            width: "20px",
-                                            height: "3px",
+                                            width: "24px",
+                                            height: "4px",
                                             borderRadius: "2px",
                                             background: "var(--weekly-border, #e5e7eb)",
                                             position: "relative",
@@ -9744,7 +9783,7 @@ function TaskItem({
                                                 height: "100%",
                                                 width: `${pct}%`,
                                                 borderRadius: "2px",
-                                                background: allDone ? "var(--weekly-teal, #0d9488)" : "#6366f1",
+                                                background: allDone ? "var(--weekly-teal, #0d9488)" : "var(--weekly-accent, #6366f1)",
                                                 transition: "width 0.3s ease",
                                             }} />
                                         </span>