.timeline { list-style: none; padding-left: 0; border-left: 2px solid #dee2e6; margin-left: 0.5rem; }
.timeline li { position: relative; padding: 0.5rem 0 0.5rem 1.25rem; }
.timeline li::before {
  content: "";
  position: absolute; left: -7px; top: 1rem;
  width: 10px; height: 10px; border-radius: 50%;
  background: #0d6efd;
}
.parent-code { font-family: monospace; color: #6c757d; }