Craft a musical piece in accordance with the designated structure and theme.
X:1
L:1/8
Q:1/8=128
M:4/4
K:Bb
['d>c B2']  
X:1
L:1/8
Q:1/8=128
M:4/4
K:Bb
|: g | B<B d>c B2 B>F | G>B F>B d<c c>g | B<B d>c B2 B>d | c/d/c/B/ A/G/F/E/ D<B, B,g | 
 B<B d>c B2 B>F | G>B F>B d<c c>g | B<B d>c B2 B>d | c/d/c/B/ A/G/F/E/ D<B, B,B | 
 D<B, B,>G D<B, B,>B | DB, G/F/E/D/ EC CB | DB, DF EG FB | e<g c>e d<B B2 | D<B, B,>G D<B, B,>B | 
 DB, G/F/E/D/ EC Cg | f>e d>c B2 B>d | c/d/c/B/ A/G/F/E/ D<B, B, :|  