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                <!--Nguồn W3 School:>
 <a class="button1" onclick="typeWriter()">
  <span class="btn1">Run Effect</span>
<p id="hieu_ung_danh_chu"></p>
  var i = 0;
 var vanBan = 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed pulvinar dolor ut imperdiet congue. Nunc vel eleifend ipsum. Praesent in facilisis leo';
 var tocDo = 50;
function typeWriter() {
   if (i < vanBan.length) {
     document.getElementById("hieu_ung_danh_chu").innerHTML += vanBan.charAt(i);
     setTimeout(typeWriter, tocDo );


                @import url('');
  font-family: 'Noto Sans JP', sans-serif;
.button1 {
   background-image: linear-gradient(135deg, #008aff, #86d472);
   border-radius: 6px;
   box-sizing: border-box;
   color: #ffffff;
   display: block;
   height: 50px;
   font-size: 1.2em;
   font-weight: 600;
   padding: 4px;
   position: relative;
   text-decoration: none;
   width: 7em;
   z-index: 2;
  cursor: pointer;
.button1:hover {
   color: #fff;
.button1 .btn1 {
   align-items: center;
   background: #0e0e10;
   border-radius: 6px;
   display: flex;
   justify-content: center;
   height: 100%;
   transition: background 0.5s ease;
   width: 100%;
.button1:hover .btn1 {
   background: transparent;