Act as a senior frontend developer with 5+ years of experience in React and design systems. Create a step-by-step guide on how to integrate and effectively use Chakra UI in a [React project type, e.g., 'Next.js application']. Cover the following topics in detail: 1) Setting up Chakra UI with [package manager, e.g., 'npm' or 'yarn'], 2) Customizing the default theme for [specific use case, e.g., 'dark mode' or 'brand consistency'], and 3) Building a responsive layout using Chakra's [component, e.g., 'Box' or 'Grid'] components. Include code snippets, best practices, and common pitfalls to avoid. Tailor the guide for [audience, e.g., 'beginners' or 'intermediate developers'].