Designed with three stylized, human-like cats lined up front and center on an emerald green background sprinkled with small white shamrocks ☘️. On the left stands a dark green cat with round, calm eyes and fine whiskers, angled just enough to feel like it’s leaning toward the others like a close friend. In the middle, a white cat wears irregular green polka dots, its gentle expression and slight inward tilt giving the trio a cozy, together-at-the-party closeness 💚. On the right, a ginger cat adds warm contrast, its bright orange coat and relaxed face making the group look comfortable and connected. Across the top, the phrase “HAPPY ST. CATTY’S DAY” is set in large, chunky letters, centered above the cats. The word “HAPPY” mixes colors to match the characters, with darker green used for “HA” and “PY,” and the first “P” in orange that echoes the ginger cat. Near the bottom, “Grandpa” appears in small white text under the cats, and the flat shapes keep everything simple against the shamrock-dotted green field.