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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

  <svg viewBox="0 0 400 200">
    <path d="M50,150 C50,0 200,0 200,75 C200,150 350,150 350,0" fill="none"/>
  <div class="mover"></div>

  <label for="anchor-x">X</label>
  <input type="range" id="anchor-x" value="50" min="0" max="100"/>
  <output id="output-x">50%</output>

  <label for="anchor-y">Y</label>
  <input type="range" id="anchor-y" value="50" min="0" max="100"/>
  <output id="output-y">50%</output>
              :root {
  --duration: 9000ms;

svg, main {
  width: 400px;
  height: 200px;
  position: relative;
path {
  stroke: #d8d8dd;
  stroke-width: 2px;
svg {
  position: absolute;

.mover {
  --anchorX: 50%;
  --anchorY: 50%;
  position: absolute;
  height: 50px;
  width: 50px;
  background: hsla(183, 90%, 54%, .3);
  border: 2px solid hsl(183, 100%, 54%);
  border-right-color: hsl(43, 100%, 50%);
  border-left-color: hsl(343, 100%, 50%);
  display: flex;
  justify-content: center;
  align-items: center;
  color: white;
  offset-path: path("M50,150 C50,0 200,0 200,75 C200,150 350,150 350,0");
  offset-rotate: auto 90deg;
  offset-anchor: var(--anchorX) var(--anchorY);
  animation: move-along var(--duration) 0ms infinite alternate ease-in-out;
.mover::after {
  content: '';
  position: absolute;
  background: radial-gradient(circle at var(--anchorX) var(--anchorY), red 3px, transparent 3px) no-repeat;
  width: 100%;
  left: 0;
  bottom: 0;
  top: 0;

aside {
  display: none;

@supports (offset-anchor: 70% 70%) {
  aside {
    display: grid;
@supports (offset-position: 70% 70%) {
  #position {
    display: block;
@keyframes move-along {
  100% {
    offset-distance: 100%;

body {
  min-height: 100vh;
  background: #16161c;
  font-family: system-ui, sans-serif;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  color: hsl(183,100%, 97%);
  padding: 2rem 0;
  box-sizing: border-box;
aside {
  margin: 0rem 1rem;
  grid-template-columns: 4em 1fr 4em;
  grid-gap: 1em;
label {
  text-align: right;
input {
  margin-bottom: 1rem;
output {
  opacity: .7;
              var x = document.getElementById('anchor-x');
var y = document.getElementById('anchor-y');
var outputx = document.getElementById('output-x');
var outputy = document.getElementById('output-y');
var mover = document.querySelector('.mover');

x.addEventListener('input', function(e) {
  let x = `${e.currentTarget.value}%`;'--anchorX', x);
  outputx.textContent = x;
y.addEventListener('input', function(e) {
  let y = `${e.currentTarget.value}%`;'--anchorY', y);
  outputy.textContent = y;
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