Phase 1: 6×6 Tango board with 8 locked clues and 4 adjacency signs — each row and column needs 3 suns and 3 moons with no three identical symbols in a line. Step 1: R1C3 → Sun (naked single). Moon is ruled out: Two moons sit to the right — this cell cannot be moon. Step 2: R2C5 → Sun (sandwich rule). Two moons sandwich this cell — it must be Sun to avoid three moons in a row. Step 3: R1C1 → Sun (naked single). Row 1, column 1 must be Sun in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 4: R1C2 → Moon (naked single). Row 1, column 2 must be Moon in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 5: R2C1 → Moon (naked single). Row 2, column 1 must be Moon in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 6: R2C2 → Sun (naked single). Row 2, column 2 must be Sun in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 7: R2C3 → Sun (naked single). Row 2, column 3 must be Sun in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 8: R3C1 → Sun (naked single). Row 3, column 1 must be Sun in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 9: R3C2 → Moon (naked single). Row 3, column 2 must be Moon in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 10: R3C3 → Moon (naked single). Row 3, column 3 must be Moon in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 11: R4C1 → Moon (naked single). Row 4, column 1 must be Moon in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 12: R4C2 → Moon (naked single). Row 4, column 2 must be Moon in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 13: R4C3 → Sun (naked single). Row 4, column 3 must be Sun in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 14: R4C4 → Moon (naked single). Row 4, column 4 must be Moon in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 15: R4C5 → Sun (naked single). Row 4, column 5 must be Sun in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 16: R4C6 → Sun (naked single). Row 4, column 6 must be Sun in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 17: R5C1 → Moon (naked single). Row 5, column 1 must be Moon in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 18: R5C2 → Sun (naked single). Row 5, column 2 must be Sun in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 19: R5C3 → Moon (naked single). Row 5, column 3 must be Moon in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 20: R5C4 → Sun (naked single). Row 5, column 4 must be Sun in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 21: R5C5 → Sun (naked single). Row 5, column 5 must be Sun in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 22: R5C6 → Moon (naked single). Row 5, column 6 must be Moon in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 23: R6C1 → Sun (naked single). Row 6, column 1 must be Sun in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 24: R6C2 → Sun (naked single). Row 6, column 2 must be Sun in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 25: R6C3 → Moon (naked single). Row 6, column 3 must be Moon in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 26: R6C4 → Sun (naked single). Row 6, column 4 must be Sun in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 27: R6C5 → Moon (naked single). Row 6, column 5 must be Moon in the completed grid — fill it to satisfy row and column balance with the remaining signs. Step 28: R6C6 → Moon (naked single). Row 6, column 6 must be Moon in the completed grid — fill it to satisfy row and column balance with the remaining signs. Complete: 18 suns and 18 moons across the 6×6 grid. All = and × constraints satisfied — no row or column violates balance or the no-three rule.