<div class="demo-preview-block"> <div class="demo-button"> <button id="alertdialog" class="mdl-button mdl-js-button mdl-button--raised mdl-button--colored mdl-js-ripple-effect">Alert dialog </button> <button id="confirmdialog" class="mdl-button mdl-js-button mdl-button--raised mdl-button--colored mdl-js-ripple-effect">Confirm dialog </button> <button id="customdialog1" class="mdl-button mdl-js-button mdl-button--raised mdl-button--colored mdl-js-ripple-effect">Custom dialog I </button> <button id="customdialog2" class="mdl-button mdl-js-button mdl-button--raised mdl-button--colored mdl-js-ripple-effect">Custom dialog II </button> </div> </div>