Find Root Node in Colored Tree with Pattern Constraints

Given an undirected connected acyclic graph where each node has at most 3 edges and nodes are colored (Red/Black/White or similar color patterns), find a root node such that when the graph is viewed as a binary tree from that root, it satisfies specific color pattern constraints across levels (e.g., RBWRBW repeating pattern or alternating colors). Return -1 if no valid root exists.