.case-nav {
  --case-glass-x: 50%;
  isolation: isolate;
}

.case-nav::before {
  content: "";
  position: absolute;
  z-index: -2;
  inset: -16px -22px;
  border: 1px solid rgba(255, 255, 255, .78);
  border-radius: 999px;
  background: linear-gradient(112deg, rgba(254, 246, 244, .72), rgba(255, 255, 255, .62) 42%, rgba(255, 240, 244, .68));
  box-shadow: 0 14px 44px rgba(65, 25, 37, .12), inset 0 1px 0 rgba(255, 255, 255, .92);
  backdrop-filter: blur(24px) saturate(1.55);
  -webkit-backdrop-filter: blur(24px) saturate(1.55);
  opacity: 0;
  transform: translateY(-18px) scale(.985);
  transition: opacity .42s ease, transform .48s cubic-bezier(.2, .8, .2, 1);
  pointer-events: none;
}

.case-nav::after {
  content: "";
  position: absolute;
  z-index: -1;
  inset: -14px -19px;
  border-radius: 999px;
  background:
    radial-gradient(circle at var(--case-glass-x) 44%, rgba(255, 255, 255, .9), transparent 20%),
    radial-gradient(circle at 14% 42%, rgba(255, 255, 255, .72), transparent 24%),
    radial-gradient(circle at 76% 72%, rgba(249, 23, 72, .1), transparent 29%);
  filter: blur(7px);
  opacity: 0;
  transition: opacity .5s ease;
  pointer-events: none;
}

.case-nav.is-scrolled::before,
.case-nav.is-scrolled::after {
  opacity: 1;
}

.case-nav.is-scrolled::before {
  transform: translateY(0) scale(1);
}

@media (max-width: 800px) {
  .case-nav::before {
    inset: -9px -11px;
    border-radius: 25px;
    transform: translateY(-12px) scale(.985);
  }

  .case-nav::after {
    inset: -7px -9px;
    border-radius: 23px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .case-nav::before,
  .case-nav::after {
    transition: none;
  }
}