data-mage-init accordion
<div data-mage-init='{"accordion":{"openedState": "active", "collapsible": true, "active": false, "multipleCollapsible": false}}'>
<div data-role="collapsible">
<div data-role="trigger">
Title 1
</div>
</div>
<div data-role="content">
<p>
Content 1
</p>
</div>
<div data-role="collapsible">
<div data-role="trigger">
Title 2
</div>
</div>
<div data-role="content">
<p>
Content 2
</p>
</div>
</div>