.scroll-top {
  position: fixed;
  bottom: var(--space-6);
  right: var(--space-6);
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--color-primary);
  color: var(--color-white);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: all var(--transition-base);
  z-index: var(--z-sticky);
  cursor: pointer;
  z-index: calc(var(--z-chat) - 1);
}

.scroll-top--visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.scroll-top:hover {
  background: var(--color-primary-dark);
  transform: translateY(-4px);
  box-shadow: var(--shadow-glow);
}

.scroll-top svg {
  width: 20px;
  height: 20px;
}

@media (max-width: 480px) {
  .scroll-top {
    right: var(--space-4);
    bottom: var(--space-4);
    width: 42px;
    height: 42px;
  }
}