responsive-design

Use a mobile-first approach with CSS media queries and fluid units. Start with single-column layouts for small screens, then add breakpoints that expand to multi-column grids as viewport width increases. This ensures one codebase adapts across all devices.

Responsive typography uses relative units like rem or em instead of fixed pixels, combined with media queries to adjust font sizes at key breakpoints. This maintains readability and visual hierarchy from mobile to desktop without manual adjustments.

Media queries detect viewport width and apply different CSS rules at breakpoints you define. Breakpoints—typically at 480px, 768px, and 1024px—trigger layout changes like hiding sidebars, adjusting grid columns, or resizing containers to fit each device class.

Yes. Flexbox and CSS Grid with percentage-based widths, combined with flexible container constraints, create layouts that reflow dynamically. Relative units maintain proportions across devices without hardcoding pixel dimensions.

Pure CSS responsive design requires careful manual breakpoint selection and testing across devices. Complex interactions, dynamic content sizing, and cross-browser media query support can demand workarounds, and performance optimization for images and assets remains a manual task.

Responsive design covers both. Use media queries to serve different image sizes, employ `srcset` for resolution-aware images, and apply max-width constraints to maintain aspect ratios. This optimizes performance and visual quality across all screen sizes.