BUG:Fix Min/max markers on box plot are not visible with 'dark_background' theme pandas-dev#40769

Author: yeshsurya

pandas/plotting/_matplotlib/boxplot.py

@@ -101,7 +101,7 @@ def _validate_color_args(self):
         self._boxes_c = colors[0]
         self._whiskers_c = colors[0]
         self._medians_c = colors[2]
-        self._caps_c = "k"  # mpl default
+        self._caps_c = colors[0]   
 
     def _get_colors(self, num_colors=None, color_kwds="color"):
         pass