Developer Design Sandbox

CSS Flexbox & Grid Layout Generator

Design advanced, nested web layouts visually. Build complex grids and nested containers tree-style, and instantly export production-ready HTML/CSS code.

Pane A: Visual Sandbox Canvas

Presets:

Root Container(flex)

Flex Box Left(flex)

Item A(block)

Empty Block

Item B(block)

Empty Block

Grid Layout Right(grid)

Cell 1(block)

Empty Block

Cell 2(block)

Empty Block

Pane B: DOM Tree Blueprint Hierarchy

Root Containerflex

Flex Box Leftflex

Item Ablock

Item Bblock

Grid Layout Rightgrid

Cell 1block

Cell 2block

Editing Node: Root Container

Element Name

Display Mode

Flex Direction

Justify Content

Align Items

Gap Spacing16px

Inner Padding24px

Outer Margin0px

Width

Height

Semantic HTML Architecture

<div class="root-container">
  <div class="flex-box-left">
    <div class="item-a">
      <!-- Item A Content -->
    </div>
    <div class="item-b">
      <!-- Item B Content -->
    </div>
  </div>
  <div class="grid-layout-right">
    <div class="cell-1">
      <!-- Cell 1 Content -->
    </div>
    <div class="cell-2">
      <!-- Cell 2 Content -->
    </div>
  </div>
</div>

CSS Stylesheet Rules

.root-container {
  display: flex;
  flex-direction: row;
  justify-content: center;
  align-items: stretch;
  gap: 16px;
  padding: 24px;
  width: 100%;
  height: 100%;
  flex-grow: 1;
}

.flex-box-left {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 8px;
  padding: 16px;
  margin: 8px;
  width: 50%;
  flex-grow: 1;
}

.item-a {
  display: block;
  padding: 12px;
  margin: 4px;
  width: 100%;
}

.item-b {
  display: block;
  padding: 12px;
  margin: 4px;
  width: 100%;
}

.grid-layout-right {
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: auto;
  gap: 12px;
  padding: 16px;
  margin: 8px;
  width: 50%;
  flex-grow: 1;
}

.cell-1 {
  display: block;
  padding: 12px;
  margin: 4px;
}

.cell-2 {
  display: block;
  padding: 12px;
  margin: 4px;
}

How the CSS Flexbox & Grid Layout Generator Works

Visualise responsive containers, nested components, and dynamic grid layouts instantly in 3 steps.

Select Active Nodes

Manage your layouts in a hierarchical tree. Select the root container or any nested item directly in Pane A or the Pane B Blueprint list.

Configure Flex & Grid Properties

Switch active nodes from Flex to Grid, define responsive repeat templates, customize margins, paddings, item alignments, and row gaps.

Export Clean Compiled Code

Traverse the entire structural tree dynamically to generate beautifully indented semantic HTML tags and production-ready clean CSS files.

FAQs: Layout Generators

Answers to common queries about nested Flexbox and CSS Grid layout generation.

Q.What is a nested layout inside this builder?

A nested layout lets you change a child item display into another flex container or grid layout. This allows the construction of complex visual components like navigation headers, cards grids, or complete application structures.

Q.How does CSS Grid fraction sizing work?

Fractional sizing (fr) represents a fraction of the available space inside the grid container. For example, "1fr 2fr" splits columns such that the second column occupies double the horizontal space of the first.

Q.Are the exported HTML & CSS layout rules standard-compliant?

Absolutely! Our compilation compiler produces fully standardized semantic HTML5 codes and clean, cross-browser compatible vanilla CSS style class declarations.

Q.When should I use Flexbox vs. CSS Grid?

Use Flexbox for one-dimensional layouts (e.g. standard content rows, dynamic column menus, item alignments). Use CSS Grid for complex, two-dimensional layout grids (e.g., repeating cards grid systems, dashboard templates).