[html]

<style>
body {
  margin: 2rem 0.5rem;
  background-color: #c4c8cc;
  color: #404448;
  font-family: 'Open Sans', 'Helvetica Neue', Helvetica, Arial, sans-serif;
  line-height: 1.4;
}

.card {
  margin: 0 auto 2rem;
  padding: 1rem;
  min-width: 10rem;
  max-width: 60rem;
display: table;
  background-color: white;
  word-wrap: break-word;
  box-shadow: 0 0.0625em 0.1875em 0 rgba(0, 0, 0, 0.1), 0 0.5em 0 -0.25em #f2f2f2, 0 0.5em 0.1875em -0.25em rgba(0, 0, 0, 0.1), 0 1em 0 -0.5em #e6e6e6, 0 1em 0.1875em -0.5em rgba(0, 0, 0, 0.1);
}
.card.card-dark {
  color: #d0d0d0;
}
.card.card-dark {
  background-color: #404040;
  box-shadow: 0 0.0625em 0.1875em 0 rgba(0, 0, 0, 0.1), 0 0.5em 0 -0.25em #3d3d3d, 0 0.5em 0.1875em -0.25em rgba(0, 0, 0, 0.1), 0 1em 0 -0.5em #3a3a3a, 0 1em 0.1875em -0.5em rgba(0, 0, 0, 0.1);
}
.card > :last-child {
  margin-bottom: 0;
}
.card-n {
    margin-top: 20px;
    border-top: 1px solid #5f5f5f;
}
.spoilerclose {
    height: 58px;
    outline: none;
    position: relative;
    overflow: hidden;
    margin: 0 auto;
}
.spoilerclose:before {
    content: "▿";
    text-align: center;
    line-height: 60px;
    color: #548c7d;
    font-size: 56px;
    cursor: pointer;
    width: 56px;
    height: 56px;
    display: block;
    border: 1px solid #548c7d;
    border-radius: 50px;
    margin: 0 auto;
    transform: rotate(180deg);
}
.spoileropen {
    height:58px;
    outline: none;
    float: left;
    position: relative;
    overflow: hidden;
}
.spoileropen:before {
content: "▿";
    text-align: center;
    line-height: 60px;
    color: #548c7d;
    font-size: 56px;
    cursor: pointer;
    width: 56px;
    height: 56px;
    display: block;
    border: 1px solid #548c7d;
    border-radius: 50px;
    margin: 0 auto;

}
.spoileropen:focus {
    height: auto;
}
.spoileropen:focus .spoilerclose {
    display: block;
}
.spoileropen:focus:before {
    display: none;
}
</style>

<div class="card card-dark">
<div class="spoileropen" role="tab" tabindex="1">
        <span role="button" tabindex="0" class="spoilerclose"></span>
    <div role="tabpanel" class="card-n">
    <p>Some very cool stuff goes there</p>
    </div>
</div>
</div>

[/html]