acha-framework/src/frontend/core/scripts/directives/accordion/template.html

is a modular framework on both client (angular.js) and server (node.js) side, it provides security, orm, ioc, obfuscation and ...

<div ng-show="visible" class="af-accordion af-component accordion panel-group {{::cssClass}}" role="tablist">
    <div ng-repeat="step in steps" class="panel panel-default">
        <div class="panel-heading" role="tab">
            <div class="panel-title">
                <a role="button"
                   href="javascript:void(0)"
                   data-toggle="collapse"
                   ng-click="vm.onPick(step)"
                   class="{{step !== model?'collapsed':''}}">
                    &nbsp;{{$eval(step.title)|textOrTranslate:$eval(step.titleTranslate)}}
                </a>
            </div>
        </div>
        <div class="panel-collapse {{step !== model?'collapse':''}}"
             role="tabpanel">
            <div class="panel-body"
                 ng-bind-html="step.content|to_trusted_html"></div>
        </div>
    </div>
</div>