Correct

一抹黑

/ yī mǒhēi / 
Strokes

Example

As an Adjective

completely dark; pitch-dark

1
Yī
一
tíngdiàn
停电
  
,
wūzi
屋子
lǐ
里
yī
一
mǒhēi
抹黑
  
。

It was pitch-dark in the room when the power was cut.

2
Liǎng
两
yǎn
眼
yī
一
mǒhēi
抹黑

be in total confusion; be totally at loss