diff --git a/frontend/src/views/CaptureOverlay.vue b/frontend/src/views/CaptureOverlay.vue
index 73e785b..3fdf4e0 100644
--- a/frontend/src/views/CaptureOverlay.vue
+++ b/frontend/src/views/CaptureOverlay.vue
@@ -111,14 +111,24 @@ const sizeLabel = computed(() => {
   return `${Math.round(rect.value.w)} × ${Math.round(rect.value.h)}`
 })
 
+const MARK_TOOLBAR_W = 190
+const ACTION_TOOLBAR_W = 180
+const TOOLBAR_GROUP_GAP = 8
+
 const rightToolbarPos = computed(() => {
   if (!rect.value) return null
-  return placeToolbar(rect.value, 180, 40, 'right')
+  return placeToolbar(rect.value, ACTION_TOOLBAR_W, 40, 'right')
 })
 
 const leftToolbarPos = computed(() => {
-  if (!rect.value) return null
-  return placeToolbar(rect.value, 190, 40, 'left')
+  if (!rect.value || !rightToolbarPos.value) return null
+  // 标记组与操作组合并到右侧，紧贴在操作组左侧，中间保留间隔
+  const x = clamp(
+    rightToolbarPos.value.x - TOOLBAR_GROUP_GAP - MARK_TOOLBAR_W,
+    0,
+    props.width - MARK_TOOLBAR_W
+  )
+  return { x, y: rightToolbarPos.value.y }
 })
 
 const handles = computed(() => {
diff --git a/native_overlay_darwin.go b/native_overlay_darwin.go
index ad8f3e8..bc93774 100644
--- a/native_overlay_darwin.go
+++ b/native_overlay_darwin.go
@@ -633,8 +633,11 @@ static id nativeOverlayKeyMonitor = nil;
     [_saveRemoteButton setFrame:NSMakeRect(baseX + (actionBtnSize + actionGap) * 3, btnY, actionBtnSize, actionBtnSize)];
     [_uploadButton     setFrame:NSMakeRect(baseX + (actionBtnSize + actionGap) * 4, btnY, actionBtnSize, actionBtnSize)];
 
+    // Mark toolbar sits to the LEFT of the action toolbar (same row) with an
+    // 8px gap between the two groups, so they never overlap on tiny selections.
     CGFloat markW = 170;
-    CGFloat markX = MAX(0, MIN(_selection.origin.x, self.bounds.size.width - markW));
+    CGFloat markGap = 8;
+    CGFloat markX = MAX(0, x - markGap - markW);
     [_penButton setFrame:NSMakeRect(markX + 4, y + 4, 28, 28)];
     [_rectButton setFrame:NSMakeRect(markX + 36, y + 4, 28, 28)];
     [_ellipseButton setFrame:NSMakeRect(markX + 68, y + 4, 28, 28)];