Adjust Font using LabelingFunction in a BarChart in Mathematica

Considering the following BarChart :

How Could I adjust the Font for the Labeling Function as well as the Chart Labels ?

I tried nesting Style. Unsuccessfull.

BarChart[{1, 2, 3, 4},
ChartStyle -> {Blue, Red, Green, Yellow},
开发者_StackOverflowLabelStyle -> Directive[Black, Large],
ChartLabels -> {"COG1", "COG2", "COG3", "COG4"},
ImageSize -> {500, 300},
ChartBaseStyle -> EdgeForm[Thick],
LabelingFunction -> Bottom,
Background -> Black,
LabelStyle -> Directive[Black, Large]]

Do you mean something like this?

BarChart[{1, 2, 3, 4}, 
 ChartStyle -> {Blue, Red, Green, Yellow}, 
 ChartLabels -> (Style[#, Large, White] & /@ {"COG1", "COG2", "COG3", "COG4"}),
 LabelingFunction -> (Placed[Style[#, Large], Bottom] &), 
 ImageSize -> {500, 300},
 ChartBaseStyle -> EdgeForm[Thick], 
 Background -> Black,
 AxesStyle -> White, LabelStyle -> {Large}]

Edit

Change the style of the axes.