<zing-grid
  caption="Air Quotes"
  src="https://zinggrid-examples.firebaseio.com/air-quotes"
  layout="card"
  layout-controls="false"
  pager
  page-size="6"
  page-size-options="3,6,9,12">
  <zg-colgroup>
    <zg-column index="quote" header="&nbsp;">
      &#8220;[[index.quote]]&#8221;
    </zg-column>
    <zg-column index="author" header="&nbsp;"><em>&#8212; [[index.author]]</em></zg-column>
    <zg-column renderer="_bindAccordion" cell-class="accordion-flex-layout" index="author, bio" header="&nbsp;">
      <template>
        <section class="accordion">
          <input type="checkbox" id="changeme" >
          <label for="changeme">About the Author</label>
          <article>
            <p class="authorBio">[[index.bio]]</p>
          </article>
        </section>
      </template>
    </zg-column>
  </zg-colgroup>
  <zg-footer>
    <p>Biography sources: <a href="https://www.wikipedia.org/" target="_blank" crossorigin>Wikipedia</a>
  </zg-footer>
</zing-grid>

body{
  background:#e6e6e6;
  padding: 50px 0;
  font-family: 'Noto Serif', serif;
}

zing-grid {
	max-width: 1000px;
  margin: 0 auto;
  font-family: 'Noto Serif', serif;
  --theme-color-primary: #383838;
  background: none; 
  color: #414141;
  border: none;
  --zg-pager-font-size: 11px;
  --zg-row-body-background_hover: #f4fbff;
  --zg-row-color_hover: #383838;
}

zg-caption {
  background: none; 
  color: #414141;
  font-size: 40px;
  font-weight: bold;
  text-align: center;
  margin-bottom: 20px;
}

zg-body {
  background: none; 
  color: #414141;
}

zg-row {
  background: #ffffff;
}

zg-row[layout="card"] {
  border-radius: 10px;
  -webkit-border-radius: 10px;
  -moz-border-radius: 10px;
  margin: 10px;
  box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.1), 0 6px 20px 0 rgba(0, 0, 0, 0.09);
}

zg-body[layout="card"] {
  --zg-card-columns: 33.3%;
}

[data-field-index="author"] {
  align-items: center;
  justify-content: center;
	font-family: 'Muli', sans-serif;
}

zg-cell:nth-child(1) {
  font-size: 17px;
  line-height: 1.3;
  text-align: center;
}

zg-cell:nth-child(2) {
  font-size: 12px;
  line-height: 1.3;
  color: #a8a8a8;
}

zg-row[layout="row"] zg-cell:nth-child(1) {
  text-align: left;
}

zg-watermark {
  background: none;
  border: none;
  font-family: 'Muli', sans-serif;
  justify-content: center;
  font-size: 11px;
  margin-top: 10px;
}

zg-footer {
  font-family: 'Muli', sans-serif;
  text-align: center;
  font-size: 12px;
  margin-top: 20px;
}

.accordion-flex-layout {
  --zg-cell-vertical-align: top;
}

/* target accordion for mobile and display as column*/
zing-grid[viewport="mobile"]  .accordion-container {
  flex-direction:column;
  flex-grow: 1;
}

/* Main accordion styling */
.accordion input {
	display: none;
}

.accordion label {
	position:relative;
  display: block;
	background: #f7f7f7;
	border-radius: .25em;
	cursor: pointer;
	margin-bottom: .125em;
	padding: .75rem 1em;
	z-index: 20;
  border: 1px solid #cccccc;
  text-align: center;
  font-size: 13px;
}

.accordion label:hover {
	background: #ccc;
}

.accordion input:checked + label {
	background: #dddddd;
	border-bottom-right-radius: 0;
	border-bottom-left-radius: 0;
	color: #383838;
	margin-bottom: -1px;
}

.accordion label::after {
  content: '+';  
  position:absolute;
  right:5px;
}

.accordion input:checked + label::after {
  content: '-';  
  position:absolute;
  right:5px;
}

.accordion article {
	background: #f9f9f9;
	/* 
	 * max-height allows height transition in CSS 
	 * use height: 0px; otherwise
	 */
	max-height:0px;
	overflow:hidden;
	z-index:10;
	opacity:0;
	/* allow closing transition */
	-webkit-transition: all 0.7s ease; 
  -moz-transition: all 0.7s ease;
  -o-transition: all 0.7s ease;
	transition: all 0.7s ease;
  border: 1px solid #cccccc;
  color: #383838;
  font-size: 13px;
  line-height: 1.5;
}

.accordion article {
	padding: 1em;
	cursor: default;
}

.accordion input:checked article {
}

.accordion input:checked ~ article {
	border-bottom-left-radius: .25em;
	border-bottom-right-radius: .25em;
	/* 
	 * max-height allows height transition in CSS 
	 * use height: auto; otherwise
	 */
	max-height: 500px;
	margin-bottom: .125em;
	opacity: 1;
	/* allow opening transition */
	-webkit-transition: all 1s ease; /* Safari */
  -moz-transition: all 1s ease;
  -o-transition: all 1s ease;
	transition: all 1s ease;
}

// global event handler for expanding dropdowns
const expandHandler = function() {
  this.classList.toggle('active');
  this.nextElementSibling.classList.toggle('show');
}

// generate randomId for dropdownsreturn Math.random().toString(36).replace(/[^a-z]+/g, '').substr(2, 10);
const randomId = () => {
  return Math.random().toString(36).replace(/[^a-z]+/g, '').substr(2, 10);
}

// custom render function for coach info accordion
function _bindAccordion(name, bio, cellRef, $cell) {
  // grab template contents
  const $input = cellRef.querySelector('input');
  const $label = cellRef.querySelector('label');
  
  // assign template attributes and custom id's
  // so the label for will trigger the dropdown
  const dropdownID = randomId();
  $input.setAttribute('id', `accordion_${dropdownID}`);
  $label.setAttribute('for', `accordion_${dropdownID}`);
};