A high-end commercial graphic design poster with a 3:4 aspect ratio, strictly following the Neo Brutalism style. The composition features a sophisticated digital interface layout for a 'Color, Gradient & Accessibility Checker'. The typography is bold and impactful, prominently displaying the text: 'Color, Gradient & Accessibility Checker' and '(Aesthetic Accessibility)'. The visual language uses thick black strokes, high-contrast shadows, and an asymmetrical grid. The color palette is a harmonious professional mix of deep slate, electric indigo, and clinical white. Professional studio lighting illuminates floating UI cards that demonstrate color contrast ratios. The design includes high-end textures like subtle paper grain and glassmorphism accents. Elements are placed with proper breathing room, showcasing a masterclass in visual hierarchy and agency-grade post-production. 4k resolution, award-winning design, masterpiece quality, commercial-grade aesthetic.