offset-distance

The offset-distance CSS property specifies a position along an offset-path for an element to be placed.

/* Default value */
offset-distance: 0;

/* the middle of the offset-path */
offset-distance: 50%;

/* a fixed length positioned along the path */
offset-distance: 40px;

/* Global values */
offset-distance: inherit;
offset-distance: initial;
offset-distance: revert;
offset-distance: unset;

<length-percentage>

A length that specifies how far the element is along the path (defined with offset-path).

100% represents the total length of the path (when the offset-path is defined as a basic shape or path()).

<length-percentage>
where 
<length-percentage> = <length> | <percentage>

The motion aspect in CSS Motion Path typically comes from animating the offset-distance property. If you want to animate an element along its full path, you would define its offset-path and then set up an animation that takes the offset-distance from 0% to 100%.

HTML

<div id="motion-demo"></div>

CSS

#motion-demo {
  offset-path: path('M20,20 C20,100 200,0 200,100');
  animation: move 3000ms infinite alternate ease-in-out;
  width: 40px;
  height: 40px;
  background: cyan;
}

@keyframes move {
  0% {
    offset-distance: 0%;
  }
  100% {
    offset-distance: 100%;
  }
}

Result

• offset
• offset-anchor
• offset-path
• offset-position
• offset-rotate