#rttb-return-to-top.rttb-button {
  position: fixed;
  bottom: var(--rttb-bottom, 24px);
  right: var(--rttb-right, 24px);
  z-index: 9999;

  width: var(--rttb-size, 44px);
  height: var(--rttb-size, 44px);

  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;

  border: none;
  border-radius: 999px;
  background: var(--rttb-bg, #111827);
  color: var(--rttb-color, #ffffff);

  box-shadow: 0 10px 25px rgba(0,0,0,0.25);
  cursor: pointer;

  opacity: 0;
  transform: translateY(8px);
  pointer-events: none;
  transition: opacity .2s ease, transform .2s ease;
}

#rttb-return-to-top.rttb-button.is-visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

#rttb-return-to-top.rttb-button:hover {
  filter: brightness(1.08);
}

#rttb-return-to-top.rttb-button:focus-visible {
  outline: 3px solid rgba(59,130,246,0.75);
  outline-offset: 3px;
}

#rttb-return-to-top .rttb-icon {
  font-size: 18px;
  line-height: 1;
}

#rttb-return-to-top .rttb-text {
  font-size: 14px;
  white-space: nowrap;
  display: none;
}

@media (min-width: 768px) {
  #rttb-return-to-top.rttb-button {
    padding: 0 14px;
    width: auto;
  }
  #rttb-return-to-top .rttb-text {
    display: inline;
  }
}