/*
 * Archive addition (2026): the sidebar avatar occasionally spins to show the
 * spring 2014 photo, like an iMessage contact photo flipping to its Memoji.
 * Sizing matches the original .index--sidebar-image rules.
 */
.avatar-flip {
  display: inline-block;
  perspective: 600px;
}
.avatar-flip__card {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 1;
  transform-style: preserve-3d;
  transition: transform 1.2s cubic-bezier(0.25, 0.8, 0.3, 1.04);
}
.avatar-flip__face {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
}
.avatar-flip__back {
  transform: rotateY(180deg);
}
/* A slight dip in size mid-spin, then a settle. */
.avatar-flip.is-spinning {
  animation: avatar-flip-dip 1.2s ease-in-out;
}
@keyframes avatar-flip-dip {
  50% { transform: scale(0.9); }
}
@media (prefers-reduced-motion: reduce) {
  .avatar-flip__card { transition: none; }
  .avatar-flip.is-spinning { animation: none; }
}