/* Scroll to top — фирменная кнопка «наверх» (тёмно-синий градиент Эстом) */

.rv-stt {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 1100;
  display: flex;
  align-items: center;
  justify-content: center;
  flex: none;
  box-sizing: border-box;
  width: 52px;
  height: 52px;
  min-width: 52px;
  max-width: 52px;
  min-height: 52px;
  max-height: 52px;
  padding: 0;
  margin: 0;
  line-height: 0;
  border: 0;
  border-radius: 50%;
  background: linear-gradient(
    135deg,
    var(--color-primary-deep) 0%,
    var(--color-primary) 100%
  );
  color: #fff;
  cursor: pointer;
  box-shadow: var(--shadow-fab);
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px);
  transition:
    opacity 0.25s ease,
    visibility 0.25s ease,
    transform 0.25s ease,
    background 0.2s ease,
    box-shadow 0.2s ease;
}

.rv-stt.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.rv-stt:hover {
  background: linear-gradient(
    135deg,
    var(--color-primary-dark) 0%,
    var(--color-primary-dark) 40%,
    #1743ad 100%
  );
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}

.rv-stt:active {
  transform: translateY(-1px);
}

.rv-stt svg {
  display: block;
}

@media (max-width: 640px) {
  .rv-stt {
    right: 14px;
    bottom: 14px;
    width: 44px;
    height: 44px;
    min-width: 44px;
    max-width: 44px;
    min-height: 44px;
    max-height: 44px;
  }

  .rv-stt svg {
    width: 19px;
    height: 19px;
  }
}

/* плавающая иконка мессенджера MAX — иконка, при наведении круглая рамка */
.rv-max-fab {
  bottom: 88px;
  width: 52px;
  height: 52px;
  min-width: 52px;
  max-width: 52px;
  min-height: 52px;
  max-height: 52px;
  border-radius: 50%;
  background: transparent;
  border: 1.5px solid transparent;
  box-shadow: none;
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
  transition:
    transform 0.15s ease,
    background 0.15s ease,
    border-color 0.15s ease;
}

.rv-max-fab:hover {
  transform: scale(1.06);
  background: #fff;
  border-color: #16abdf;
  box-shadow: 0 10px 26px rgba(10, 16, 60, 0.18);
}

@media (max-width: 640px) {
  .rv-max-fab {
    right: 14px;
    bottom: 70px;
    width: 44px;
    height: 44px;
    min-width: 44px;
    max-width: 44px;
    min-height: 44px;
    max-height: 44px;
  }
}