Create a detailed anime-style illustration of a confident young athlete. The character has short, slightly wavy hair styled in a modern mullet, colored in a muted grayish-brown tone. Their expression is relaxed and confident, with a subtle smile and warm brown almond-shaped eyes. They wear a dark navy-blue sports jersey featuring the logo and text 'Ultimate Champions' on the chest, along with a vibrant multicolored graphic design at the bottom. One sleeve is casually rolled up, enhancing the sporty, laid-back vibe. The background is a soft pale greenish-gray, simple yet complementary, keeping the character as the central focus. Use clean, polished lines and pastel tones to give the artwork a fresh and modern anime aesthetic