cards.css in Open Social 8.3

.card {
  -webkit-box-shadow: 0 -1px 0 #e0e0e0, 0 0 2px rgba(0, 0, 0, 0.12), 0 2px 4px rgba(0, 0, 0, 0.24);
          box-shadow: 0 -1px 0 #e0e0e0, 0 0 2px rgba(0, 0, 0, 0.12), 0 2px 4px rgba(0, 0, 0, 0.24);
  position: relative;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-orient: vertical;
  -webkit-box-direction: normal;
      -ms-flex-direction: column;
          flex-direction: column;
  margin-bottom: 0.75rem;
  background-clip: padding-box;
  -webkit-box-flex: 1;
      -ms-flex-positive: 1;
          flex-grow: 1;
}

.card__title {
  position: relative;
  vertical-align: middle;
  margin: 0;
  padding: 15px 1.25rem 0;
  line-height: 1;
  font-size: 1rem;
}

.card__subtitle {
  font-size: 0.75rem;
  display: block;
}

.card__title--underline {
  border-bottom: 1px solid #e6e6e6;
  padding-bottom: 15px;
}

.card__block {
  position: relative;
  -webkit-box-flex: 1;
      -ms-flex: 1 1 auto;
          flex: 1 1 auto;
  padding: 1.25rem;
}

.card__block + .card__block {
  padding-top: 0;
}

.card__block--table {
  padding: 1.25rem 0;
}

.card__block--list:not(:first-child) {
  padding-top: 0;
}

.card__block--list:not(:last-child) {
  padding-bottom: 0;
}

.card__body {
  position: relative;
  padding: 1.25rem;
}

.card__body .twitter-tweet,
.card__body .fb_iframe_widget,
.card__body iframe {
  max-width: 100% !important;
  width: 100% !important;
}

.card__nested-section {
  margin-top: 0.625rem;
  margin-right: -1.25rem;
  margin-bottom: -1.25rem;
  margin-left: -1.25rem;
  padding: 1.25rem;
  background: #f7f7f7;
  border-top: 1px solid #e6e6e6;
}

.card__actionbar {
  margin-top: -1.25rem;
  padding: 1.25rem;
  position: relative;
  z-index: 2;
}

.card__actionbar:before, .card__actionbar:after {
  content: " ";
  display: table;
}

.card__actionbar:after {
  clear: both;
}

.card__link {
  font-size: 0.875rem;
  margin-left: 24px;
  float: right;
  -webkit-transition: color .3s ease;
  transition: color .3s ease;
}

.card__text {
  margin-top: 0;
}

.card__text:last-child {
  margin-bottom: 0;
}

@media (min-width: 900px) {
  .card__body {
    padding: 2.5rem;
  }
}