The country is Venezuela. Its flag has three horizontal stripes: yellow on top, blue in the middle, and red on the bottom.

A nearby lookalike is Colombia , but Colombia’s yellow stripe is much wider than the blue and red, so it is not the exact equal-striped version you described.

Quick note

  • Venezuela: equal horizontal yellow, blue, red stripes.
  • Colombia: yellow, blue, red, but the yellow band is larger.
  • Ecuador also uses yellow, blue, and red, but it includes a coat of arms in the center.

TL;DR: Venezuela.