Create responsive web designs that work across all devices and screen sizes. Use when building mobile-first layouts, implementing breakpoints, or optimizing for different viewports. Handles CSS Grid, Flexbox, media queries, viewport units, and responsive images.
87
82%
Does it follow best practices?
Impact
99%
1.08xAverage score across 3 eval scenarios
Passed
No known issues
Mobile-first breakpoints and layout
Viewport meta tag
100%
100%
Mobile-first default styles
10%
100%
min-width queries only
0%
100%
Standard breakpoints used
100%
100%
Relative units for font-size
100%
100%
Relative units for spacing
85%
85%
No fixed container width
100%
100%
No duplicate base styles
100%
100%
Flexbox for navigation
100%
100%
Grid for features section
100%
100%
Grid column count changes across breakpoints
62%
100%
Relative width for grid/flex items
100%
100%
Fluid typography and container queries
clamp() for body font
100%
100%
clamp() for headings
100%
100%
CSS custom properties for font sizes
100%
100%
container-type declaration
100%
100%
@container query used
100%
100%
Container name used
100%
100%
Card layout changes by container
100%
100%
Relative units for spacing
100%
100%
No fixed width on container
100%
100%
Viewport meta tag
100%
100%
min-width queries (if any media queries present)
100%
100%
line-height set on headings
100%
100%
Responsive images and grid gallery
srcset attribute on images
100%
100%
sizes attribute on images
100%
100%
Hero uses picture or image-set
100%
100%
Background media query breakpoints
100%
100%
Lazy loading
100%
100%
CSS Grid for gallery
100%
100%
Grid column count changes at breakpoints
100%
100%
Mobile-first grid default
100%
100%
No fixed image width
100%
100%
aspect-ratio or height: auto
100%
100%
Viewport meta tag
100%
100%
min-width queries only
66%
100%
c033769
Table of Contents
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