Toast Slide-In

The element glides in from off its container edge to its resting position without fading.

Add a "Slide In" entrance animation (also called slide in left, slide in right, slide in up or slide in down) to [where].
The element should glide in from beyond its container edge to its resting place, fully opaque the whole time: quick, decelerating smoothly with no bounce.
Clip it at the container edge so it doesn't overlap neighbours or cause scrollbars while it is outside, and show it in place when the user prefers reduced motion (prefers-reduced-motion).

A small label fades and nudges into place next to an element after a short hover delay.

Add a "Tooltip Fade" (also called a tooltip reveal) to [where].
After a short hover delay, the label should fade in while nudging slightly into place next to the element, then disappear quickly with no delay when the pointer leaves.
Show it on keyboard focus too, let Escape dismiss it, and connect it to the element so screen readers read it.

A panel slides up from the bottom edge, often draggable and snapping to heights.

Add a "Bottom Sheet Slide-Up" (also called a bottom drawer or sheet) to [where].
The panel should slide up from the bottom edge while the page behind it dims, decelerating smoothly into place without a bounce.
Play it once each time the sheet opens, slide it back down on close, and keep keyboard focus inside the sheet while it is open.

The element fades in while drifting a short distance from one side into its final position.

Add a "Fade In Directional" entrance animation (also called fade in left, fade in right or fade in down) to [where].
The element should fade in while drifting a short distance from one side into its final position: quick and smooth, easing out as it lands, without bounce.
Play it once, and show the element in place without motion when the user prefers reduced motion (prefers-reduced-motion).

A content panel smoothly grows to its full height or shrinks to zero when its header is toggled.

Add an "Accordion Expand-Collapse" effect (also called a collapse or disclosure) to [where].
When a header is pressed, its panel should smoothly grow to the full height of its content and shrink back to nothing on the next press, with the header's arrow turning to match: quick and smooth, no bounce.
Animate to the content's real height rather than a fixed guess, keep the header a real button that exposes its expanded state, and make it work from the keyboard.

A translucent dark layer fades in behind an overlay to dim the page.

Add a "Backdrop Scrim Fade" (also called an overlay fade or scrim) to [where].
When the overlay opens, a translucent dark layer should fade in softly over the page behind it, a little slower than the overlay itself, and fade out again when it closes.
Keep the scrim dark in both light and dark themes, and stop the page behind it from scrolling or taking clicks while it is shown.