30 CSS Sidebar Layouts09 / 30

Pure CSSMIT licensed

CSS Fixed Sidebar Layout with Independent Scrollable Main Content

The foundational app-shell every dashboard starts from — a locked left sidebar and a main pane that scrolls on its own — built the modern way: not position:fixed with magic margins, but a height-constrained grid where each pane owns its own overflow. Scrollbars stay where they belong, nothing overlaps, and the pattern nests cleanly inside any container.

Published Updated

Live Demo
Try it

The code

<section class="sbl-08">
  <aside class="sbl-08__rail" aria-label="Workspace">
    <div class="sbl-08__brand"><span aria-hidden="true"></span>Ledgerly</div>
    <nav class="sbl-08__nav">
      <a href="#" aria-current="page">Overview</a><a href="#">Transactions</a><a href="#">Invoices</a><a href="#">Recurring</a><a href="#">Vendors</a><a href="#">Categories</a><a href="#">Receipts</a><a href="#">Tax reports</a><a href="#">Bank feeds</a><a href="#">Rules</a><a href="#">Integrations</a><a href="#">Team</a><a href="#">Settings</a>
    </nav>
  </aside>
  <main class="sbl-08__main">
    <h1>Overview</h1>
    <p>Both panes scroll independently. The sidebar nav is intentionally long — scroll it, then scroll this pane; neither moves the other.</p>
    <div class="sbl-08__stack"><div></div><div></div><div></div><div></div><div></div><div></div></div>
  </main>
</section>
.sbl-08,
.sbl-08 *,
.sbl-08 *::before,
.sbl-08 *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

.sbl-08 {
  --panel: oklch(0.17 0.015 235);
  --ink: oklch(0.93 0.005 235);
  --mut: oklch(0.63 0.012 235);
  --line: oklch(0.28 0.015 235);
  --accent: oklch(0.72 0.13 210);
  display: grid;
  grid-template-columns: 260px 1fr;
  height: 100vh;
  height: 100dvh;
  font-family: system-ui,'Segoe UI',sans-serif;
  background: oklch(0.13 0.012 235);
  color: var(--ink);
}

.sbl-08__rail {
  display: flex;
  flex-direction: column;
  background: var(--panel);
  border-right: 1px solid var(--line);
  overflow-y: auto;
  overscroll-behavior: contain;
  scrollbar-width: thin;
  scrollbar-color: var(--line) transparent;
  padding: 20px 12px;
}

.sbl-08__brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font: 700 15px/1 system-ui,sans-serif;
  padding: 2px 10px 18px;
}

.sbl-08__brand span {
  width: 24px;
  height: 24px;
  border-radius: 7px;
  background: conic-gradient(from 45deg,var(--accent),oklch(0.6 0.15 260));
}

.sbl-08__nav {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.sbl-08__nav a {
  padding: 10px 14px;
  border-radius: 9px;
  font: 500 13.5px/1 system-ui,sans-serif;
  color: var(--mut);
  text-decoration: none;
  transition: background-color .18s ease,color .18s ease;
}

.sbl-08__nav a:hover {
  color: var(--ink);
  background: color-mix(in oklab,var(--ink) 6%,transparent);
}

.sbl-08__nav a[aria-current="page"] {
  color: var(--ink);
  background: color-mix(in oklab,var(--accent) 17%,transparent);
  box-shadow: inset 2px 0 0 var(--accent);
}

.sbl-08__nav a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.sbl-08__main {
  overflow-y: auto;
  overscroll-behavior: contain;
  scrollbar-gutter: stable;
  padding: 32px;
}

.sbl-08__main h1 {
  font: 600 22px/1.2 system-ui,sans-serif;
  margin-bottom: 10px;
}

.sbl-08__main p {
  color: var(--mut);
  font-size: 14px;
  line-height: 1.6;
  max-width: 52ch;
  margin-bottom: 24px;
  text-wrap: pretty;
}

.sbl-08__stack {
  display: grid;
  gap: 16px;
}

.sbl-08__stack div {
  height: 130px;
  border-radius: 14px;
  background: var(--panel);
  border: 1px solid var(--line);
}

@media (prefers-reduced-motion: reduce) {
  .sbl-08__nav a {
    transition: none;
  }
}
/* No JavaScript — a height-constrained grid shell; each pane owns overflow-y:auto + overscroll-behavior:contain, so scrolling never couples. */
Paste this into ChatGPT, Claude, Cursor, or any coding assistant. The block below is pre-framed with everything the AI needs to integrate this demo into your project — markup, styles, scoping notes, and the source URL. Hit Copy and paste straight into your chat.
Here's a working CSS Sidebar Layout from CodeFronts. Use it as-is or adapt to your framework. All classes are scoped under a unique prefix so the code won't collide with your existing styles. MIT licensed.
Demo: CSS Fixed Sidebar Layout with Independent Scrollable Main Content
Source: https://codefronts.com/layouts/css-sidebar-layouts/fixed-sidebar/

The foundational app-shell every dashboard starts from — a locked left sidebar and a main pane that scrolls on its own — built the modern way: not position:fixed with magic margins, but a height-constrained grid where each pane owns its own overflow. Scrollbars stay where they belong, nothing overlaps, and the pattern nests cleanly inside any container.
## HTML
```html
<section class="sbl-08">
  <aside class="sbl-08__rail" aria-label="Workspace">
    <div class="sbl-08__brand"><span aria-hidden="true"></span>Ledgerly</div>
    <nav class="sbl-08__nav">
      <a href="#" aria-current="page">Overview</a><a href="#">Transactions</a><a href="#">Invoices</a><a href="#">Recurring</a><a href="#">Vendors</a><a href="#">Categories</a><a href="#">Receipts</a><a href="#">Tax reports</a><a href="#">Bank feeds</a><a href="#">Rules</a><a href="#">Integrations</a><a href="#">Team</a><a href="#">Settings</a>
    </nav>
  </aside>
  <main class="sbl-08__main">
    <h1>Overview</h1>
    <p>Both panes scroll independently. The sidebar nav is intentionally long — scroll it, then scroll this pane; neither moves the other.</p>
    <div class="sbl-08__stack"><div></div><div></div><div></div><div></div><div></div><div></div></div>
  </main>
</section>
```
## CSS
```css
.sbl-08,
.sbl-08 *,
.sbl-08 *::before,
.sbl-08 *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

.sbl-08 {
  --panel: oklch(0.17 0.015 235);
  --ink: oklch(0.93 0.005 235);
  --mut: oklch(0.63 0.012 235);
  --line: oklch(0.28 0.015 235);
  --accent: oklch(0.72 0.13 210);
  display: grid;
  grid-template-columns: 260px 1fr;
  height: 100vh;
  height: 100dvh;
  font-family: system-ui,'Segoe UI',sans-serif;
  background: oklch(0.13 0.012 235);
  color: var(--ink);
}

.sbl-08__rail {
  display: flex;
  flex-direction: column;
  background: var(--panel);
  border-right: 1px solid var(--line);
  overflow-y: auto;
  overscroll-behavior: contain;
  scrollbar-width: thin;
  scrollbar-color: var(--line) transparent;
  padding: 20px 12px;
}

.sbl-08__brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font: 700 15px/1 system-ui,sans-serif;
  padding: 2px 10px 18px;
}

.sbl-08__brand span {
  width: 24px;
  height: 24px;
  border-radius: 7px;
  background: conic-gradient(from 45deg,var(--accent),oklch(0.6 0.15 260));
}

.sbl-08__nav {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.sbl-08__nav a {
  padding: 10px 14px;
  border-radius: 9px;
  font: 500 13.5px/1 system-ui,sans-serif;
  color: var(--mut);
  text-decoration: none;
  transition: background-color .18s ease,color .18s ease;
}

.sbl-08__nav a:hover {
  color: var(--ink);
  background: color-mix(in oklab,var(--ink) 6%,transparent);
}

.sbl-08__nav a[aria-current="page"] {
  color: var(--ink);
  background: color-mix(in oklab,var(--accent) 17%,transparent);
  box-shadow: inset 2px 0 0 var(--accent);
}

.sbl-08__nav a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.sbl-08__main {
  overflow-y: auto;
  overscroll-behavior: contain;
  scrollbar-gutter: stable;
  padding: 32px;
}

.sbl-08__main h1 {
  font: 600 22px/1.2 system-ui,sans-serif;
  margin-bottom: 10px;
}

.sbl-08__main p {
  color: var(--mut);
  font-size: 14px;
  line-height: 1.6;
  max-width: 52ch;
  margin-bottom: 24px;
  text-wrap: pretty;
}

.sbl-08__stack {
  display: grid;
  gap: 16px;
}

.sbl-08__stack div {
  height: 130px;
  border-radius: 14px;
  background: var(--panel);
  border: 1px solid var(--line);
}

@media (prefers-reduced-motion: reduce) {
  .sbl-08__nav a {
    transition: none;
  }
}
```

## JavaScript
```js
/* No JavaScript — a height-constrained grid shell; each pane owns overflow-y:auto + overscroll-behavior:contain, so scrolling never couples. */
```

How this works

The classic recipe (position:fixed sidebar + margin-left:260px content) has sharp edges: fixed elements escape their container, break inside transformed ancestors, and need the margin kept in sync by hand. The grid version removes all of it: display:grid; grid-template-columns:260px 1fr; height:100dvh on the shell, then overflow-y:auto on each pane. The height constraint is what makes it work — panes can't grow past the viewport, so they scroll internally. The sidebar is effectively 'fixed' because the shell itself never scrolls.

Both scroll areas get the finishing details that read as native quality: overscroll-behavior:contain so a fast-scrolling sidebar doesn't chain-scroll the content behind it, scrollbar-width:thin + scrollbar-color for a rail-matched scrollbar (the standards-based replacement for ::-webkit-scrollbar), and scrollbar-gutter:stable on the main pane so content doesn't shift 15px when a scrollbar appears. The long nav here scrolls to prove the sidebar's independence.

Make it yours

  • Width: 260px fits icon+label nav; use clamp(220px, 18vw, 300px) for a fluid rail on ultrawide monitors.
  • The dvh unit (not vh) is deliberate — it tracks mobile browser chrome; keep the plain vh line before it as the fallback.
  • Add a fixed header row by extending to grid-template-rows:56px 1fr with the sidebar spanning both rows.
  • This shell is the base layer: demos 02, 09, 17 and 21 all assume exactly this structure underneath.

Gotchas — read before shipping

  • Every ancestor between body and the shell must not constrain height, or 100dvh overflows — set height:100% up the chain or mount the shell at body level.
  • overflow on the PANES, never the shell — shell-level scrolling recreates the coupled-scroll problem the grid exists to solve.
  • scrollbar-color styles both rails; test contrast in light mode — a too-subtle thumb fails visible-affordance heuristics for long content.

Browser support

ChromeSafariFirefoxEdge
121+18.2+97+121+

Versions gate scrollbar-color/width only — cosmetic. The grid shell itself works in every engine since 2017.

Techniques used in this demo

scrollbar-gutter / -width / -colorMDN ↗conic-gradient()MDN ↗text-wrap: prettyMDN ↗color-mix()MDN ↗grid-templateMDN ↗oklch()MDN ↗

Search CodeFronts

Loading…

↑↓ navigate↵ selectesc closeOpen full search page →