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Design

What is Responsive Design?

A web design approach that makes pages render well on all screen sizes and devices, from desktop monitors to mobile phones.

Responsive design uses flexible layouts, images, and CSS media queries to adapt content to any screen size. The same HTML serves all devices, with CSS controlling the presentation.

Responsive design principles

Fluid grids

  • Use percentages instead of fixed widths
  • Columns adjust to screen width
  • Content reflows naturally

Flexible images

img {
  max-width: 100%;
  height: auto;
}

Media queries

@media (max-width: 768px) {
  .sidebar {
    display: none;
  }
}

Responsive vs adaptive

  • Responsive: Fluid layouts that adjust continuously
  • Adaptive: Fixed layouts that change at breakpoints

Common breakpoints

  • Mobile: 320-480px
  • Tablet: 481-768px
  • Laptop: 769-1024px
  • Desktop: 1025px+

Responsive design and CLS

Poorly implemented responsive design can cause CLS:

  • Images without explicit dimensions
  • Dynamic content loading
  • Fonts causing layout shifts

Always reserve space for content to prevent shifts.

Monitor your website performance

VitalSentinel tracks Core Web Vitals and performance metrics to help you stay ahead of issues.