.container {
display: grid;
grid-template-columns: repeat(3, 1fr);
grid-template-rows: repeat(2, auto);
column-gap: 16px;
row-gap: 16px;
justify-items: stretch;
align-items: stretch;
justify-content: stretch;
align-content: normal;
}CSS Grid and Flexbox are the two primary layout systems in modern CSS, each defined in their own W3C specifications. Grid Layout (CSS Grid Level 1) excels at two-dimensional layouts — placing items across both rows and columns simultaneously. Flexbox (CSS Flexible Box Layout) optimizes one-dimensional alignment — distributing space along a single axis with powerful alignment controls. Both are supported in all modern browsers and expose numerous configuration properties that are difficult to memorize and test without a visual feedback loop.
In Grid mode, the generator exposes controls for grid-template-columns (column count or custom fr/px values), grid-template-rows, gap (row-gap and column-gap independently), and item placement properties. The preview renders a grid with numbered placeholder items and updates instantly as you adjust any property. Column definitions are expressed using repeat() notation and fr units for flexible tracks.
In Flexbox mode, the generator exposes flex-direction, flex-wrap, justify-content, align-items, align-content, and per-item flex-grow, flex-shrink, and flex-basis controls. The preview renders several flex items of varying natural sizes so you can see how the alignment properties interact with different content sizes.
CSS output is generated as a complete ruleset including the container declaration and all item overrides. Tailwind output maps each property to its closest utility class using Tailwind v4 defaults, and uses arbitrary value syntax for values outside the standard scale.
A frontend developer builds a three-column product grid and exports the Tailwind classes to paste directly into a Next.js component without guessing class names.
A developer creates a responsive sidebar layout using Grid areas and copies the CSS to use as a starting template for a dashboard page.
A student learning CSS layout uses the visual editor to understand how justify-content and align-items interact before writing any code manually.
A developer replicates a Figma auto-layout frame as Flexbox CSS, verifying the alignment matches the design using the live preview.
Choose between Grid or Flexbox layout mode
Set columns, rows, gaps and alignment properties
Preview the layout live with resizable items
Copy generated CSS or Tailwind classes
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