Particles

Tiny stars twinkle or drift across a dark space-like backdrop.

Add a "Starfield" background (also called a stars background or twinkling stars) to [where].
Tiny stars of different sizes should twinkle softly at their own pace while the whole field drifts very slowly: quiet and calm.
Keep the number of stars modest so it stays light, and stop the twinkling and drift for users who prefer reduced motion.

Small bright specks flicker in and out around text or a section.

Add a "Sparkles" effect (also called glitter or twinkle particles) to [where].
Small star-shaped specks should pop in, twinkle and fade out around the text at scattered spots and random moments: light and quick.
Keep the sparkles decorative and hidden from screen readers, never cover the text itself, and stop them for users who prefer reduced motion.

Particles spiral around a center like a whirlpool.

Add a "Vortex" background (also called swirling particles) to [where].
Small particles should spiral inward around a center point like a whirlpool, fading in at the edge and fading out as they reach the middle, in a smooth, continuous swirl.
Keep the particle count modest, pause it when off screen, and stop the swirl for users who prefer reduced motion.

Colorful paper pieces burst out and fall to celebrate a success.

Add a "Confetti" celebration (also called a confetti burst) to [where].
Small colorful paper pieces should burst quickly out of the button, then tumble and drift down as they fade away, in a short, lively shower.
Fire it once per success rather than looping, keep it from blocking clicks on the page, and skip it for users who prefer reduced motion.

Blur strength ramps gradually toward an edge so content fades out softly.

Add a "Progressive Blur" edge (also called a gradient blur edge) to [where].
Content scrolling toward the edge should get gradually blurrier and softer, ramping smoothly instead of cutting off at a hard line.
Show the blur only at an edge that still has more content beyond it, and keep the blurred area from blocking clicks or scrolling.

A tilted perspective grid scrolls toward the viewer like a synthwave floor.

Add a "Retro Grid" background (also called a perspective grid or synthwave grid) to [where].
A grid floor tilted away in perspective should scroll steadily toward the viewer and fade out into the horizon: smooth and endless.
Make the loop seamless so the lines never jump, and stop the scrolling for users who prefer reduced motion.

Concentric circles expand outward from a center point and fade.

Add a "Ripple Rings" effect (also called a background ripple or concentric ripples) to [where].
Rings should keep expanding outward from a center point and fade as they grow, evenly spaced one after another: slow and steady.
Keep the center element still and in place, and stop the ripples for users who prefer reduced motion.