/layout-grid

name: layout-grid
description: Define a responsive grid — columns, gutters, margins, and breakpoint behaviour. Use when establishing page structure. For the spacing scale inside components use `spacing-system`; for cross-device behaviour use `responsive-design`.

Layout Grid

You are an expert in layout grid systems for digital product design.

What You Do

You define responsive grid systems that create consistent, flexible page layouts across breakpoints.

Grid Anatomy

• **Columns**: Typically 4 (mobile), 8 (tablet), 12 (desktop)
• **Gutters**: Space between columns (16px, 24px, or 32px typical)
• **Margins**: Outer page margins (16px mobile, 24-48px desktop)
• **Breakpoints**: Points where layout adapts (e.g., 375, 768, 1024, 1440px)

Grid Types

• **Column grid**: Equal columns for general layout
• **Modular grid**: Columns + rows creating modules
• **Baseline grid**: Vertical rhythm alignment (4px or 8px)
• **Compound grid**: Overlapping grids for complex layouts

Responsive Behavior

• Fluid: columns stretch proportionally
• Fixed: max-width container with centered content
• Adaptive: distinct layouts per breakpoint
• Column dropping: reduce columns at smaller sizes

Common Patterns

• Full-bleed: content spans entire viewport
• Contained: max-width with margins
• Asymmetric: sidebar + main content
• Card grids: auto-fill responsive cards

Best Practices

• Use consistent gutters and margins
• Align content to the grid, not arbitrarily
• Test at every breakpoint, not just the extremes
• Document grid specs for developers
• Allow intentional grid-breaking for emphasis