Modern digital product, design rules, user interface architecture, minimalism, flat design, clean layout, intuitive navigation, responsive web, mobile app, desktop application, Windows, macOS, iOS, Android, material design, skeuomorphism, 3D visual effects, subtle animations, interactive elements, hover effects, dropdown menus, button styles, typography, sans-serif fonts, bold font weights, soft color palette, pastel colors, white space, grid system, alignment, symmetry, balance, contrast, emphasis, hierarchy, proximity, repetition, consistency, feedback, discoverability, aesthetics, usability, accessibility, user experience, wireframing, prototyping, high-fidelity design, design system, style guide, human-centered design.