Act as a professional logo designer with 5+ years of experience in tech and education branding. Create a sleek, modern logo for an AI-powered language learning app called [APP_NAME]. The logo should embody [KEY_THEME] (e.g., connectivity, intelligence, or cultural fusion) and use a color palette of [PRIMARY_COLOR], [SECONDARY_COLOR], and [ACCENT_COLOR]. Incorporate subtle AI elements (e.g., neural networks, speech bubbles, or globe motifs) while maintaining simplicity for scalability. The design must work on dark/light backgrounds and as a standalone icon (minimum 32x32px). Avoid clichés like alphabet letters or flags—focus on innovation. Provide 3 style variations: flat, gradient, and isometric. Include a 1-sentence rationale for each design choice.