相关疑难解决方法(0)

.panel-heading .accordion-toggle:after {
    font-family: 'Glyphicons Halflings';
    content: "\e114";
    float: right;
    color: grey;
}

.panel-heading .accordion-toggle.collapsed:after {
    content: "\e080";
}

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">


<div class="panel-group" id="accordion">
    <div class="panel panel-default">
        <div class="panel-heading">
            <h3 class="panel-title">
                <a class="accordion-toggle" data-toggle="collapse" data-parent="#accordion" href="#importationCollapse">Importation</a>
            </h3>
        </div>
        <div id="importationCollapse" class="panel-collapse collapse in">
            <div class="panel-body">
            <p>Content: blahblah</p>
            </div>
        </div>
    </div>
</div>