slidein

Slide-in refers to a user interface animation pattern in which an element enters the visible area by sliding from an edge, often from the left or right, or from the bottom. It is commonly used for side panels, drawers, menus, notifications, or promotional banners, and can be triggered by user action, on scroll, or when content becomes visible.

In web design, slide-in effects are usually implemented with CSS transitions or keyframe animations that move the element using transforms and adjust opacity. A slide-in from the left or right typically starts with the element translated offscreen and at low opacity, then moves to its resting position with full opacity. A slide-in from the top or bottom uses vertical translation. For performance, these animations typically rely on transforms and opacity rather than layout changes, and developers may reference the prefers-reduced-motion media feature to respect accessibility needs.

Common patterns include slide-in drawers or panels that cover part of the screen, slide-in menus, and slide-in banners embedded within content. Triggers can be a button click, scrolling to a threshold, or a page navigation event. Slide-ins are often accompanied by an overlay, and may include coordinated focus management to maintain accessibility.

Accessibility and usability considerations are important for slide-ins. Designers should provide a clear close control, manage focus when the element opens or closes, assign appropriate ARIA roles and labels, and ensure screen readers are informed about revealed content. When used for navigation or critical information, slide-ins should not obscure essential content for extended periods and should respect user motion preferences.