Designing for 240px keypad phones up to 4K displays: Fluid design tokens in Tailwind CSS

Building truly universal interfaces means testing on real ultra-compact screens where horizontal margins can break layouts.\n\nTechniques we adopted:\n- Full-bleed edge-to-edge shells with zero side gaps\n- Flex-wrap metadata chips to prevent text truncation\n- High-contrast D-pad focus indicators for non-touch devices