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                <ul id="wrapper">
  <li id="minimize"><svg width="11" height="1" viewBox="0 0 11 1">
      <path d="m11 0v1h-11v-1z" stroke-width=".26208" />
  <li id="maximize"><svg width="10" height="10" viewBox="0 0 10 10">
      <path d="m10-1.6667e-6v10h-10v-10zm-1.001 1.001h-7.998v7.998h7.998z" stroke-width=".25" />
  <li id="close"><svg width="12" height="12" viewBox="0 0 12 12">
      <path d="m6.8496 6 5.1504 5.1504-0.84961 0.84961-5.1504-5.1504-5.1504 5.1504-0.84961-0.84961 5.1504-5.1504-5.1504-5.1504 0.84961-0.84961 5.1504 5.1504 5.1504-5.1504 0.84961 0.84961z" stroke-width=".3" />
  <div id="highlight"></div>


                body {
  display: flex;
  justify-content: center;

ul {
  position: relative;
  list-style: none;
  display: flex;
  white-space: nowrap;
  padding: 0;

li {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  text-align: center;
  vertical-align: middle;
  padding: 0.8rem 1.2rem;
  cursor: pointer;
  border-radius: 5px;

#highlight {
  /* initially only opacity is animated: */
  transition-property: opacity;
  transition-duration: 200ms;
  transition-timing-function: cubic-bezier(0.4, 0, 0.2, 1);
  z-index: -10;
  position: absolute;
  min-height: 100%;
  border-radius: 5px;
  background-color: #bbbbbb;
  opacity: 0;

/* animation of property "left" is switched on
            when the class "transition-active" is set: */
#highlight.transition-active {
  transition-property: all;

#wrapper svg {
  transition-duration: 200ms;

#close:hover svg {
  fill: white;

#close:hover + #highlight {
  background-color: #e31219;



                const defaultSelection = document.getElementById("minimize");
const highlight = document.getElementById("highlight");
const wrapper = document.getElementById("wrapper");

let timer;

wrapper.addEventListener("mouseleave", (event) => { = 0;
  // we remove the class "transition-active"
  // so that shifting the highlight
  // is done immediately without animation
  // when the mouse is entering again:
  timer = setTimeout(() => {
  }, 200)

document.querySelectorAll("li").forEach((item) => {
  item.addEventListener("mouseover", (event) => {
    timer && clearTimeout(timer);
    // after page load or when the mouse is entering
    // the wrapper, transition is switched of,
    // therefore shifting the highlight is done without transition
    setStyles(highlight,"li")); = 1;
    // subsequently shifting the highlight should be animated,
    // therefore switch on transition
    // after waiting for a short moment:
    setTimeout(() => {
    }, 0);

function setStyles(elementToStyle, eventTarget) { = getStyles(eventTarget).w + "px"; = getStyles(eventTarget).h + "px"; = getStyles(eventTarget).pos + "px";

function getStyles(target) {
  return {
    w: target.scrollWidth,
    h: target.scrollHeight,
    pos: target.offsetLeft