<div class="container">
 <div class="accordion">
  <dl>
   <dt>
    <a href="#accordion1" aria-expanded="false" aria-controls="accordion1" class="accordion-title accordionTitle js-accordionTrigger">Template</a>
   </dt>
   <dd class="accordion-content accordionItem is-collapsed" id="accordion1" aria-hidden="true">
    <p>Nội dung Template. </p>
   </dd>
   <dt>
    <a href="#accordion2" aria-expanded="false" aria-controls="accordion2" class="accordion-title accordionTitle js-accordionTrigger">
   Thủ Thuật</a>
   </dt>
   <dd class="accordion-content accordionItem is-collapsed" id="accordion2" aria-hidden="true">
    <p>Nội dung thủ thuật.</p>
   </dd>
   <dt>
    <a href="#accordion3" aria-expanded="false" aria-controls="accordion3" class="accordion-title accordionTitle js-accordionTrigger">
   HTML5
   </a>
   </dt>
   <dd class="accordion-content accordionItem is-collapsed" id="accordion3" aria-hidden="true">
    <p>Nội dung HTML5.</p>
   </dd>
  </dl>
 </div>

</div>

<script type="text/javascript">
//uses classList, setAttribute, and querySelectorAll
//if you want this to work in IE8/9 youll need to polyfill these
(function(){
 var d = document,
 accordionToggles = d.querySelectorAll('.js-accordionTrigger'),
 setAria,
 setAccordionAria,
 switchAccordion,
  touchSupported = ('ontouchstart' in window),
  pointerSupported = ('pointerdown' in window);
 
  skipClickDelay = function(e){
 e.preventDefault();
 e.target.click();
  }

  setAriaAttr = function(el, ariaType, newProperty){
  el.setAttribute(ariaType, newProperty);
 };
 setAccordionAria = function(el1, el2, expanded){
  switch(expanded) {
   case "true":
  setAriaAttr(el1, 'aria-expanded', 'true');
  setAriaAttr(el2, 'aria-hidden', 'false');
  break;
   case "false":
  setAriaAttr(el1, 'aria-expanded', 'false');
  setAriaAttr(el2, 'aria-hidden', 'true');
  break;
   default:
    break;
  }
 };
//function
switchAccordion = function(e) {
  console.log("triggered");
 e.preventDefault();
 var thisAnswer = e.target.parentNode.nextElementSibling;
 var thisQuestion = e.target;
 if(thisAnswer.classList.contains('is-collapsed')) {
  setAccordionAria(thisQuestion, thisAnswer, 'true');
 } else {
  setAccordionAria(thisQuestion, thisAnswer, 'false');
 }
 thisQuestion.classList.toggle('is-collapsed');
 thisQuestion.classList.toggle('is-expanded');
  thisAnswer.classList.toggle('is-collapsed');
  thisAnswer.classList.toggle('is-expanded');
 
 thisAnswer.classList.toggle('animateIn');
 };
 for (var i=0,len=accordionToggles.length; i<len; i++) {
  if(touchSupported) {
   accordionToggles[i].addEventListener('touchstart', skipClickDelay, false);
 }
 if(pointerSupported){
   accordionToggles[i].addEventListener('pointerdown', skipClickDelay, false);
 }
 accordionToggles[i].addEventListener('click', switchAccordion, false);
  }
})();
</script>

.heading-primary {
  font-size: 2em;
  padding: 2em;
  text-align: center;
}

.accordion dl,
.accordion-list {
  border: 1px solid #ddd;
}
.accordion dl:after,
.accordion-list:after {
  content: "";
  display: block;
  height: 1em;
  width: 100%;
  background-color: #2ba659;
}

.accordion dd,
.accordion__panel {
  background-color: #eee;
  font-size: 1em;
  line-height: 1.5em;
}

.accordion p {
  padding: 1em 2em 1em 2em;
}

.accordion {
  position: relative;
  background-color: #eee;
}

.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 2em 0 2em 0;
}

.accordionTitle,
.accordion__Heading {
  background-color: #38cc70;
  text-align: center;
  font-weight: 700;
  padding: 2em;
  display: block;
  text-decoration: none;
  color: #fff;
  -webkit-transition: background-color 0.5s ease-in-out;
  transition: background-color 0.5s ease-in-out;
  border-bottom: 1px solid #30bb64;
}
.accordionTitle:before,
.accordion__Heading:before {
  content: "+";
  font-size: 1.5em;
  line-height: 0.5em;
  float: left;
  -webkit-transition: -webkit-transform 0.3s ease-in-out;
  transition: -webkit-transform 0.3s ease-in-out;
  transition: transform 0.3s ease-in-out;
  transition: transform 0.3s ease-in-out, -webkit-transform 0.3s ease-in-out;
}
.accordionTitle:hover,
.accordion__Heading:hover {
  background-color: #2ba659;
}

.accordionTitleActive,
.accordionTitle.is-expanded {
  background-color: #2ba659;
}
.accordionTitleActive:before,
.accordionTitle.is-expanded:before {
  -webkit-transform: rotate(-225deg);
          transform: rotate(-225deg);
}

.accordionItem {
  height: auto;
  overflow: hidden;
  max-height: 50em;
  -webkit-transition: max-height 1s;
  transition: max-height 1s;
}
@media screen and (min-width: 48em) {
  .accordionItem {
    max-height: 15em;
    -webkit-transition: max-height 0.5s;
    transition: max-height 0.5s;
  }
}

.accordionItem.is-collapsed {
  max-height: 0;
}

.no-js .accordionItem.is-collapsed {
  max-height: auto;
}

.animateIn {
  -webkit-animation: accordionIn 0.45s normal ease-in-out both 1;
          animation: accordionIn 0.45s normal ease-in-out both 1;
}

.animateOut {
  -webkit-animation: accordionOut 0.45s alternate ease-in-out both 1;
          animation: accordionOut 0.45s alternate ease-in-out both 1;
}

@-webkit-keyframes accordionIn {
  0% {
    opacity: 0;
    -webkit-transform: scale(0.9) rotateX(-60deg);
            transform: scale(0.9) rotateX(-60deg);
    -webkit-transform-origin: 50% 0;
            transform-origin: 50% 0;
  }
  100% {
    opacity: 1;
    -webkit-transform: scale(1);
            transform: scale(1);
  }
}

@keyframes accordionIn {
  0% {
    opacity: 0;
    -webkit-transform: scale(0.9) rotateX(-60deg);
            transform: scale(0.9) rotateX(-60deg);
    -webkit-transform-origin: 50% 0;
            transform-origin: 50% 0;
  }
  100% {
    opacity: 1;
    -webkit-transform: scale(1);
            transform: scale(1);
  }
}
@-webkit-keyframes accordionOut {
  0% {
    opacity: 1;
    -webkit-transform: scale(1);
            transform: scale(1);
  }
  100% {
    opacity: 0;
    -webkit-transform: scale(0.9) rotateX(-60deg);
            transform: scale(0.9) rotateX(-60deg);
  }
}
@keyframes accordionOut {
  0% {
    opacity: 1;
    -webkit-transform: scale(1);
            transform: scale(1);
  }
  100% {
    opacity: 0;
    -webkit-transform: scale(0.9) rotateX(-60deg);
            transform: scale(0.9) rotateX(-60deg);
  }
}