Rythm structure is 4 quarter notes per bar.
But with chord change in the middle of each bar.
The Verses (Dm C Bb A) use a andalusian cadence.
Here is a possible version for the main riff.
The melody uses some triplet notes to give this special groove.
whereas the chord strumming follows quarter and 8th notes
Riff for the verses (starting with Pick-up Bar)
e|---------------|
B|---------------|
G|---------------|
D|---7-10p7-10p7-|
A|---------------|
E|---------------|
[Dm] [C] [Bb] [A] [Dm] [C] [Bb] [A]
e|----------------------|------------------------|--------5-6----10---|-g10-12---10-9----------------|
B|-6--------8/10----8-5-|-6-------6----5-----6---|-6----6---5----8----|-----11-----------------------|
G|-7----------9---------|---6-7---7----6-------6-|-7--------5----9----|-----10-----------------------|
D|-7----------10--------|-8-------8----7---------|-7--------5---------|------------------7-10p7-10p7-|
A|-5--------------------|------------------------|----------3---------|------------------------------|
E|----------------------|------------------------|--------------------|------------------------------|
[Dm] [C] [Bb] [A] [Dm] [C] [Dm] [A]
e|----------------------|------------------------|--------5-6---------|----------------|
B|-6--------8/10----8-5-|-6-------6----5-----6---|-6----6---5---8---5-|---6------5-----|
G|-7----------9---------|---6-7---7----6-------6-|-7--------5---------|-6h7------6-----|
D|-7----------10--------|-8-------8----7---------|-7--------5---------|---7------7-----|
A|-5--------------------|------------------------|----------3---------|----------------|
E|----------------------|------------------------|--------------------|----------------|
---------------------------------------------------------------------------------------------------------
[Pick-up Bar]
Verse 1
[Dm] [C] [Bb] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Dm] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Dm] [A]
Chorus
[F] [F] [F] [F]
[Dm] [Dm] [G] [G]
[G] [G] [G] [G]
[C] [C] [A] [A]
Verse 2
[Dm] [C] [Bb] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Dm] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Dm] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Dm] [A]
Chorus
[F] [F] [F] [F]
[Dm] [Dm] [G] [G]
[G] [G] [G] [G]
[C] [C] [A] [A]
Outro
[Dm] [C] [Bb] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Dm] [A]
[Dm] [C] [Bb] [A]
[Dm] [C] [Bb] [A]
[Dm] [Dm]