diff --git a/klausur-service/backend/cv_box_layout.py b/klausur-service/backend/cv_box_layout.py
index 15f796f..9b72daa 100644
--- a/klausur-service/backend/cv_box_layout.py
+++ b/klausur-service/backend/cv_box_layout.py
@@ -176,7 +176,11 @@ def build_box_zone_grid(
             w.get("text", "") for w in sorted(zone_words, key=lambda ww: (ww["top"], ww["left"]))
         ).strip()
         return {
-            "columns": [{"col_index": 0, "index": 0, "label": "column_text", "col_type": "column_1"}],
+            "columns": [{"col_index": 0, "index": 0, "label": "column_text", "col_type": "column_1",
+                         "x_min_px": box_x, "x_max_px": box_x + box_w,
+                         "x_min_pct": round(box_x / img_w * 100, 2) if img_w else 0,
+                         "x_max_pct": round((box_x + box_w) / img_w * 100, 2) if img_w else 0,
+                         "bold": False}],
             "rows": [{"index": 0, "row_index": 0,
                        "y_min": box_y, "y_max": box_y + box_h, "y_center": box_y + box_h / 2,
                        "y_min_px": box_y, "y_max_px": box_y + box_h,
@@ -199,7 +203,14 @@ def build_box_zone_grid(
     if layout_type in ("flowing", "bullet_list"):
         # Force single column — each line becomes one row with one cell
         lines = _group_into_lines(zone_words)
-        column = {"col_index": 0, "index": 0, "label": "column_text", "col_type": "column_1"}
+        # Column needs x_min_px/x_max_px for GridTable width calculation
+        column = {
+            "col_index": 0, "index": 0, "label": "column_text", "col_type": "column_1",
+            "x_min_px": box_x, "x_max_px": box_x + box_w,
+            "x_min_pct": round(box_x / img_w * 100, 2) if img_w else 0,
+            "x_max_pct": round((box_x + box_w) / img_w * 100, 2) if img_w else 0,
+            "bold": False,
+        }
         rows = []
         cells = []