[TEXT ANIMATION] làm hiệu ứng chữ dòng trên xuất hiện trước rồi mới đến dòng dưới (ok)

https://codepen.io/quick-brown-fox/pen/GQrNKJ

<div class='animation'>
  text comes here
</div>
<button class='restart'>
  restart
</button>

.animation__elem {
  display: inline-block;
  margin-right: 0.3em;
  transition: transform 0.8s, opacity 0.8s;
}
.animation__elem.hidden {
  transform: translateX(100%);
  visibility: hidden;
  opacity: 0;
}
/*---------------*\
 * only for show *
\*---------------*/
body {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  height: 100vh;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
  font-weight: 200;
}
.animation {
  display: block;
  font-size: 2em;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
.restart {
  position: absolute;
  right: 1em;
  bottom: 1em;
  padding: 1rem;
  font-size: 1em;
  text-transform: uppercase;
  color: #678;
  border: 1px solid #678;
  background-color: transparent;
  cursor: pointer;
}
/*--------------*/

(function (doc) {
   // this party startet
   textAnim();

   function textAnim() {
      var con = doc.querySelector(".animation");

      if (con) {
         // get the text
         var str = con.innerHTML;
         var arr = str.split(" ");
         //delete the text from container
         con.innerHTML = "";
         // create individual elements and add them to the container
         arr.forEach(function (el) {
            if (el != "\n") {
               var newHTMLel = doc.createElement("span");
               newHTMLel.innerHTML = el;
               newHTMLel.classList.add("animation__elem", "hidden");
               con.appendChild(newHTMLel);
            }
         });

         // get the individual elements back an show them piece by piece
         var list = con.childNodes;
         var timer = 0;

         list.forEach(function (el) {
            setTimeout(function () {
               el.classList.remove("hidden");
            }, (timer += 200));
         });
      }
   }

   /*---------------*\
    * only for show *
   \*---------------*/

   var btn = doc.querySelector(".restart");

   btn.addEventListener("click", function () {
      doc.querySelector(".animation").innerHTML = "text comes here";
      textAnim();
   });
})(document);

Ví dụ 2: https://codepen.io/rachsmith/details/BNKJme

<div class="text">
  <p>Nachos are</p>
  <p>
    <span class="word wisteria">tasty.</span>
    <span class="word belize">wonderful.</span>
    <span class="word pomegranate">fancy.</span>
    <span class="word green">beautiful.</span>
    <span class="word midnight">cheap.</span>
  </p>
</div>

@import url(https://fonts.googleapis.com/css?family=Open+Sans:600);

body {
  font-family: 'Open Sans', sans-serif;
  font-weight: 600;
  font-size: 40px;
}

.text {
  position: absolute;
  width: 450px;
  left: 50%;
  margin-left: -225px;
  height: 40px;
  top: 50%;
  margin-top: -20px;
}

p {
  display: inline-block;
  vertical-align: top;
  margin: 0;
}

.word {
  position: absolute;
  width: 220px;
  opacity: 0;
}

.letter {
  display: inline-block;
  position: relative;
  float: left;
  transform: translateZ(25px);
  transform-origin: 50% 50% 25px;
}

.letter.out {
  transform: rotateX(90deg);
  transition: transform 0.32s cubic-bezier(0.55, 0.055, 0.675, 0.19);
}

.letter.behind {
  transform: rotateX(-90deg);
}

.letter.in {
  transform: rotateX(0deg);
  transition: transform 0.38s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.wisteria {
  color: #8e44ad;
}

.belize {
  color: #2980b9;
}

.pomegranate {
  color: #c0392b;
}

.green {
  color: #16a085;
}

.midnight {
  color: #2c3e50;
}

var words = document.getElementsByClassName('word');
var wordArray = [];
var currentWord = 0;

words[currentWord].style.opacity = 1;
for (var i = 0; i < words.length; i++) {
  splitLetters(words[i]);
}

function changeWord() {
  var cw = wordArray[currentWord];
  var nw = currentWord == words.length-1 ? wordArray[0] : wordArray[currentWord+1];
  for (var i = 0; i < cw.length; i++) {
    animateLetterOut(cw, i);
  }
  
  for (var i = 0; i < nw.length; i++) {
    nw[i].className = 'letter behind';
    nw[0].parentElement.style.opacity = 1;
    animateLetterIn(nw, i);
  }
  
  currentWord = (currentWord == wordArray.length-1) ? 0 : currentWord+1;
}

function animateLetterOut(cw, i) {
  setTimeout(function() {
    cw[i].className = 'letter out';
  }, i*80);
}

function animateLetterIn(nw, i) {
  setTimeout(function() {
    nw[i].className = 'letter in';
  }, 340+(i*80));
}

function splitLetters(word) {
  var content = word.innerHTML;
  word.innerHTML = '';
  var letters = [];
  for (var i = 0; i < content.length; i++) {
    var letter = document.createElement('span');
    letter.className = 'letter';
    letter.innerHTML = content.charAt(i);
    word.appendChild(letter);
    letters.push(letter);
  }
  
  wordArray.push(letters);
}

changeWord();
setInterval(changeWord, 4000);