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HTML

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CSS

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CSS Base

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <div class="wrapper">
  <div class="t1">
    <marquee>[html marquee] Hello! What time is it now?</marquee>
  </div>
  <div class="t2">
    <p>[css marquee] It's 9:30. If I have very long text..? It's 9:30. If I have very long text..?</p>
  </div>
  <div class="t3">
    <p id="marp">[JS marquee] Javascript keeps me moving :) (using requestAnimationFrame)</p>
  </div>
  <div class="t4">
    <p id="marp2">[JS marquee] Javascript keeps me moving :) (using setTimeout)</p>
  </div>
  
</div>

<div class="wrapper2">
  <div class="t5">
    <p>[CSS marquee] I move up and down.</p>
  </div>
</div>
!

CSS 

              
                * {
  font-family: sans-serif;
}

.wrapper {
  width: 300px;
  margin: auto;
  border: solid 1px tomato;
}

.t2 {
  /* for css marquee */
  overflow: hidden;
}

.t2 > p {
  animation: 7s linear 0s  infinite marquee;
/*   border: solid 1px black; */
  white-space: nowrap;
  width: fit-content;
}

@keyframes marquee {
  from {
    transform: translate(50%);
  }
  to { 
    transform: translate(-100%); 
  }
}

.t3, .t4 {
  overflow: hidden;
}

.t3 > p {
  white-space: nowrap;
  width: fit-content;
}

.t4 > p {
  white-space: nowrap;
  width: fit-content;
}


.wrapper2 {
  width: 250px;
  height: 300px;
  border: solid 1px greenyellow;
  margin: 12px auto;
}

.t5 {
  overflow: scroll;
  height: 100px;
  border: solid 1px grey;
}

.t5 > p {
  margin: 0;
  white-space: nowrap;
  width: fit-content;
  height: 100%;
  animation: 3s linear 0s  infinite marqueeUD;
}

@keyframes marqueeUD {
  from {
    transform: translateY(-100%);
  }
  to {
    transform: translateY(100%);
  }
}
!

JS 

              
                // requestAnimationFrame version
const pelm = document.getElementById("marp");
const parent_pelm = document.getElementsByClassName("t3")[0];

// この2つはt3,t4で共通
const DURATION = 5;  //sec
const PLAY_COUNT = "inf";

let startTS = null;
let play_count = 1;
function marqueef(ts) {
  let needNextReq = false;
  if(startTS == null) startTS = ts;
  const pw = pelm.clientWidth;
  const ppw = parent_pelm.clientWidth;
  const progress = (ts - startTS) / (DURATION * 1000);
  if(progress > 1) {
    if(PLAY_COUNT === "inf" || PLAY_COUNT > play_count) {
      startTS = null;
      play_count++;
      needNextReq = true;
    }
  } else {
    needNextReq = true;
  }
  
  const newpos = (pw + ppw) * (1 - progress) - pw;
  pelm.style.transform = "translate(" + newpos + "px"+")";
  
  if(needNextReq) {
    requestAnimationFrame(marqueef);
  }
}

requestAnimationFrame(marqueef);


// setTimeout version
const t4_pelm = document.getElementById("marp2");
const t4_parent_pelm = document.getElementsByClassName("t4")[0];

// 再描画間隔
const t4_INTERVAL = 1000/15;  //ms

let t4_play_count = 1;
let t4_frame_count = 0;  // 1ループ内での呼び出し回数
function t4_marqueef() {
  let needNextRender = false;
  const pw = t4_pelm.clientWidth;
  const ppw = t4_parent_pelm.clientWidth;
  const progress = (t4_frame_count * t4_INTERVAL) / (DURATION * 1000);
  if(progress > 1) {
    if(PLAY_COUNT === "inf" || PLAY_COUNT > t4_play_count) {
      t4_play_count++;
      t4_frame_count = 0;
      needNextRender = true;
    }
  } else {
    needNextRender = true;
    t4_frame_count++;
  }

  const newpos = (pw + ppw) * (1 - progress) - pw;
  t4_pelm.style.transform = "translate(" + newpos + "px"+")";
  if(needNextRender) {
    setTimeout(t4_marqueef, t4_INTERVAL);
  }
}

setTimeout(t4_marqueef, 0);
!
999px

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