body { background: #f4f6f8; }
.metric-card {
  background: white;
  border: 1px solid rgba(0,0,0,.125);
  border-radius: .5rem;
  box-shadow: 0 .125rem .25rem rgba(0,0,0,.075);
  padding: 1rem;
  height: 100%;
}
.metric-card span { display: block; color: #6c757d; font-size: .875rem; }
.metric-card strong { display: block; font-size: 1.75rem; line-height: 1.2; }