Container-Driven Layout Adaptation
Test fluid auto-grid and container queries directly inside your desktop browser without window resizing.
Interactive Device Width Simulator
Observe instant layout reflow across Desktop, Tablet and Mobile breakpoints
Simulate target container width to observe fluid reflow:
Desktop · 100%Active frame
Desktop: 4-Col Bento GridTablet: 2-Col ReflowMobile: 1-Col Stack
Fluid 12-Column Responsive Grid Visualizer
Subgrid-compatible layout system supporting fractional spans and responsive collapsing
Col 1–4 (Span 4)
Header rail
Span 4 columns.
Col 5–8 (Span 4)
Center stage
Span 4 columns.
Col 9–12 (Span 4)
Inspector rail
Span 4 columns.