Magnetic Button

Icons in a row grow smoothly as the pointer approaches, like the macOS Dock.

Add a "Dock Magnification" effect (also called dock) to [where].
Icons in the row should grow smoothly as the pointer gets closer, with the nearest icon largest and its neighbors slightly enlarged, and all return to normal size when the pointer leaves.
Grow the icons upward from a fixed baseline, and keep every icon usable at its normal size on touch and keyboard.

The card translates and scales slightly in response to pointer movement over it.

Add a "Wobble Card" effect to [where].
As the pointer moves over the card, the card should shift slightly toward it while its content shifts slightly the other way with a small scale-up, following smoothly, and everything settles back when the pointer leaves.
Keep the movement small, and turn it off on touch devices and for users who prefer reduced motion.

A field of small lines rotates to point at the pointer, like iron filings around a magnet.

Add a "Magnetic Filings" effect to [where].
A grid of short lines should each turn to point straight at the pointer right away, like iron filings around a magnet, and all face the center when there is no pointer.
Keep it a decorative background that never blocks clicks, and leave the lines still for users who prefer reduced motion.

The text caret grows or shrinks to match the size of the character it sits beside.

Add an "Adaptive Caret" effect (also called adaptive caret size) to [where].
The text caret should move in front of the character nearest the pointer and quickly stretch or shrink to match that character's height, with a smooth, snappy resize and no bounce.
Keep the text itself from shifting, and let the caret follow keyboard movement the same way it follows the pointer.

A circle cursor inverts the colors beneath it using mix-blend-mode difference.

Add a "Blend-Mode Cursor" (also called a difference cursor or inverting cursor) to [where].
Replace the pointer with a solid circle that sits directly under it with no lag and inverts the colors of the text and shapes it passes over.
Keep the blending contained to that area so it does not mix with the rest of the page, make sure it still inverts clearly in dark mode, and keep the normal cursor on touch devices.