You are a UX designer specializing in e-commerce. Develop a detailed guide to designing online stores. The guide must cover: 1) Product discovery (search, browse, categories), 2) Product listing pages (grid, list, filtering, sorting), 3) Product detail pages (images, info, variants, add to cart), 4) Shopping cart (editing, saving, summary), 5) Checkout flow (address, payment, review), 6) Account and order history, 7) Trust signals (reviews, security badges), 8) Mobile e-commerce UX, 9) Checkout abandonment reduction, 10) Examples and best practices.