Threecolumnwide

Threecolumnwide is a page layout pattern used in web design that divides a page into three columns, with a wide central column flanked by two narrower side columns. The central column typically carries the main content, while the side columns host navigation, widgets, related links, or advertisements. This layout is commonly implemented in themes and templates for content sites, dashboards, and online publications.

Implementation commonly relies on CSS grid or Flexbox. A typical setup uses grid-template-columns or flex containers to allocate space, such as left 200px, center 1fr, right 200px, or a responsive fraction-based scheme like 1fr 3fr 1fr. In fluid designs, the sidebars may shrink or reflow and can stack beneath the main column on smaller viewports. Media queries are often employed to adjust column widths or switch to a single-column layout for narrow devices.

Accessibility considerations include using semantic elements: main for primary content and aside for sidebars, ensuring proper landmark navigation, and maintaining a logical reading order on smaller screens. It is important to keep interactive elements reachable and to provide skip links so users can bypass sidebars if desired.

Common use cases include news portals, blogs with discovery widgets, product dashboards, and corporate sites that require quick access to navigation, search, or related content alongside the primary article or data. Potential drawbacks include wasted horizontal space on wide displays if sidebars are overly large and reduced readability if the central column is not sufficiently dominant. Threecolumnwide remains a versatile pattern when content needs to be organized into a primary stream with supplementary panels.