Create a realistic studio product mockup of a single large black plastic garbage bag standing upright on a clean white background. The bag is full and rounded with a squared base, glossy crinkled polyethylene texture, visible wrinkles, folds, highlights, and a tied knot at the top with gathered plastic flaring upward. Center the bag in the frame with soft, even lighting and a subtle gray shadow beneath it. Print a white custom company design on the front of the bag, consisting of exactly 3 visible printed elements: a large abstract circular logo at the upper center, the bold rounded uppercase brand name {argument name="brand name" default="CENTU"} below it, and a handwritten-style Spanish slogan {argument name="slogan text" default="¡Programando tu futuro hoy!"} underneath. Use high-contrast white ink that follows the creases and distortions of the plastic surface, making the print look physically applied to the bag rather than floating. Photorealistic commercial mockup, front-facing composition, minimal background, sharp details, natural reflections, premium branded packaging presentation.