真っ暗 (まっくら) — pitch dark, total darkness

真まっっ暗くら pitch dark

Frequency #7319 Frequency rank among common Japanese words. Lower number = more common. Grade 3 Japanese school grade level in which this kanji is taught. Grade 1 is first year of elementary school. 3 characters 混合 mixed Mixed compound — combines different reading types in a pattern that doesn't fit the standard categories. na-adjective Part of speech (JMdict: adj-na, n)

makkura

Pitch高低アクセント — Tokyo-dialect pitch accent. The number is the drop position: 0 = heiban (no drop), 1 = atamadaka (drops after 1st mora), N = drops after Nth mora. The line above each mora marks high pitch; below, low. まっくら[3] nakadaka 中高

Synth audio is approximate — the diagram is the canonical reference.