layout

CSS Sidebar + Main Two-Column Layout

A sticky sidebar with main content using CSS Grid — collapses to single column on mobile.

The sidebar + main content layout is one of the most common page patterns in web applications. This snippet uses CSS Grid for a clean two-column layout with a fixed sidebar width and fluid main content area. The sidebar uses position: sticky to stay visible while the main content scrolls, and the whole layout collapses to a single column on mobile.

Live CSS Editor

CSS

Preview

/* Sidebar + main content layout */
.layout {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 40px;
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 24px;
  align-items: start;
}

/* Sticky sidebar */
.sidebar {
  position: sticky;
  top: 80px; /* Below sticky navbar */
}

/* Sidebar nav */
.sidebar-nav {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.sidebar-link {
  display: flex;
  align-items: center;
  height: 36px;
  padding: 0 12px;
  font-size: 13px;
  border-radius: 4px;
  color: #666;
  text-decoration: none;
  transition: background 0.15s, color 0.15s;
}

.sidebar-link:hover {
  background: #f0f0f0;
  color: #111;
}

.sidebar-link.active {
  background: rgba(29, 158, 117, 0.08);
  color: #1d9e75;
  font-weight: 500;
}

/* Mobile collapse */
@media (max-width: 768px) {
  .layout {
    grid-template-columns: 1fr;
    gap: 24px;
  }

.sidebar {
    position: static;
  }
}

/* Right sidebar variant */
.layout-right-sidebar {
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: 40px;
}

@media (max-width: 900px) {
  .layout-right-sidebar {
    grid-template-columns: 1fr;
  }
}

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Usage Note

Set top: on .sidebar to match your navbar height so the sidebar sticks below the header. align-items: start on the grid container prevents the sidebar from stretching to match the main content height.