CSS Grid simplifies web layout significantly. While there's a learning curve, its intuitive nature makes it enjoyable to use, especially for managing headers and footers. This tutorial demonstrates creating both fixed and sticky footers using CSS Grid. Rachel Andrew's "The New CSS Layout" is highly recommended for a deeper dive into Grid and Flexbox.

Project Overview

We'll build a classic HTML layout with a header, main content, and footer. We'll implement two footer variations: a fixed footer that remains at the viewport bottom regardless of content length, and a traditional sticky footer that adheres to the bottom but is pushed down by longer content. The main content area will be adaptable, spanning the full viewport width or centering within a defined width.

Fixed footers, while less common than sticky footers, are used by sites like Charles Schwab. Their implementation often involves hard-coded sizes and paddings. Our approach avoids these limitations, leveraging CSS Grid's flexibility.

Before proceeding, examine the Charles Schwab homepage's fixed footer. Inspecting its code in DevTools reveals hard-coded height and positioning.

Let's achieve a similar effect without these constraints.

Initial Styles

We'll start with a minimal UI, gradually enhancing it with CSS Grid. A CodeSandbox (and subsequent iterations) provides interactive examples.

First, we ensure the viewport's full height is utilized:

body {
  margin: 0; /* prevents scrollbars */
}

#app {
  height: 100vh;
}

Next, we define the header, main, and footer sections and their grid structure. This initial structure won't function as intended yet; it serves as a foundation:

body {
  margin: 0;
}

#app {
  height: 100vh;

  /* grid container settings */
  display: grid;
  grid-template-columns: 1fr;
  grid-template-rows: auto 1fr auto;
  grid-template-areas:
    'header'
    'main'
    'footer';
}

#app > header {
  grid-area: header;
}

#app > main {
  grid-area: main;
  padding: 15px 5px 10px 5px;
}

#app > footer {
  grid-area: footer;
}

This creates a single-column layout. 1fr means "take the remaining space," resulting in full-width columns. The rows are sized using auto (for header and footer) and 1fr (for main content to fill remaining space). No hard-coded heights are necessary.

Content Integration

The provided CodeSandbox uses React for demonstration purposes, but the CSS Grid principles remain independent of the framework. Header, Main, and Footer components render the respective HTML elements. Billing and Settings sections provide sample content, demonstrating the layout's adaptability.

The initial layout shows a functional "Billing" section, but "Settings" pushes the footer off-screen. Scrolling affects the entire page, causing the header to disappear. Let's address this.

Fixed Header and Footer

The 100vh height and auto/1fr row sizing initially cause issues when content exceeds the viewport. Adding overflow: auto to the <main></main> element enables scrolling within the main content area, keeping the header and footer fixed:

#app > main {
  grid-area: main;
  overflow: auto;
  padding: 15px 5px 10px 5px;
}

This updated demo resolves the scrolling and visibility issues.

Adjustable Main Section Width

To center the main content within a 600px width or allow it to span the full viewport, we nest a grid inside <main></main>. This uses three columns (1fr 600px 1fr), effectively centering the 600px section.

#app > main {
  display: grid;
  grid-template-rows: 1fr;
  grid-template-columns: 1fr 600px 1fr;
}

Content is positioned using grid coordinates. A .full class allows content to span the entire width:

#app > section {
  grid-area: 1 / 2 / 1 / 3;
}

#app > section.full {
  grid-area: 1 / 1 / 1 / 4;
}

Note the use of grid lines (four lines for three columns). Shrinking the viewport reveals a truncation issue with the fixed 600px width. minmax(0, 600px) solves this, allowing the width to adjust up to 600px:

main {
  display: grid;
  grid-template-rows: 1fr;
  grid-template-columns: 1fr minmax(0, 600px) 1fr;
}

The final demo showcases this responsive behavior.

Traditional Sticky Footer

To create a traditional sticky footer, we modify the grid structure. The <main></main> element now contains the footer within its grid:

<div>
  <header></header>
  <main>
    <section></section>
    <footer></footer>
  </main>
</div>

The #app grid is updated to have two rows:

#app {
  /* same as before */
  grid-template-columns: 1fr;
  grid-template-rows: auto 1fr;
  grid-template-areas:
    'header'
    'main';
}

The <main></main> grid is adjusted to include the footer:

#app > main {
  display: grid;
  grid-template-rows: 1fr auto;
  grid-template-columns: 1fr minmax(0, 600px) 1fr;
}

Footer positioning within this grid:

#app > footer {
  grid-area: 2 / 1 / 3 / 4;
}

This setup allows the footer to be pushed down by content within <main></main>, creating the desired sticky footer effect. Minor padding adjustments were made to ensure proper alignment. The final demo illustrates this behavior. Additional styling was applied to the section element to allow horizontal scrolling within the content area while maintaining the vertical layout.

Conclusion

While the techniques demonstrated are achievable without CSS Grid, Grid provides a unified and elegant solution. Its flexibility and ease of use, as demonstrated by the simple transition from a fixed to a sticky footer, make it a powerful tool for complex layouts. The examples presented are relatively simple, showcasing the potential of CSS Grid for more ambitious projects.

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