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pitch-dark; pitch-black; completely dark
very bleak (future); utterly hopeless
台風の影響で停電して部屋が真っ暗になった。
The room became pitch dark due to a power outage.
街灯もない真っ暗な夜道を一人で歩くのは怖い。
Walking on a pitch dark road is scary.
将来が真っ暗に思えた時期があった。
There was a time when the future seemed dark.