.topFab{
  display: none; 

  position: fixed;
  top: calc(var(--navH) + 12px);
  right: 14px;
  z-index: 55;
  width: auto;
  height: auto;
  font-size: 18px;
  padding: 14px;
  border-radius: 999px;
  border: 1px solid rgba(255,255,255,0.12);
  background: rgba(0,0,0,0.55);
  color: var(--accent);
  font-weight: bold;
  letter-spacing: 0.02em;
  cursor: pointer;

  align-items: center;
  justify-content: center;

  opacity: 0;
  transform: translateY(-6px) scale(0.96);
  pointer-events: none;

  transition: opacity 180ms ease, transform 180ms ease, background 180ms ease, border-color 180ms ease;
}

@media (max-width: 820px){
  .topFab{
    display: inline-flex; 
  }
}

.topFab:hover{
  background: rgba(255,255,255,0.08);
  border-color: rgba(255,255,255,0.18);
}

.topFab:focus-visible{
  outline: none;
  box-shadow: 0 0 0 3px rgba(246,196,0,0.35);
}

.topFab.is-show{
  opacity: 1;
  transform: translateY(0) scale(1);
  pointer-events: auto;
}

@media (max-width: 520px){
  .topFab{
    right: 12px;
    width: 42px;
    height: 42px;
  }
}