.back-to-top svg {
  width: 23px;
  height: 23px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2.2;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.back-to-top:focus-visible {
  outline: 2px solid #e2a04a;
  outline-offset: 4px;
}
/* Au-dessus des en-têtes des pages (501), sous le menu (600), comme l'onglet de la visite (theme/css/tour.css) */
.back-to-top {
  position: fixed;
  z-index: 550;
  right: clamp(14px, 2vw, 30px);
  bottom: clamp(14px, 2vw, 28px);
  padding: 0;
  display: grid;
  place-items: center;
  border: 0;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(14px);
  transition:
    opacity 0.25s ease,
    transform 0.25s ease,
    visibility 0.25s;
  isolation: isolate;
  width: 56px;
  height: 56px;
  color: #fff;
  background: #a92d25;
  clip-path: polygon(5% 8%, 94% 3%, 100% 91%, 8% 100%, 0 18%);
  box-shadow:
    inset 0 0 0 1px #e06a574f,
    0 10px 24px #000b;
  filter: none;
}
.back-to-top:before {
  content: "";
  position: absolute;
  z-index: -1;
  inset: -5px;
  background: url("/ui/images/button-red.webp") center/100% 100% no-repeat;
  display: none;
}
.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: none;
}
.back-to-top:hover {
  transform: translateY(-3px);
  background: #c43b30;
  filter: none;
}

@media (prefers-reduced-motion: reduce) {
  .back-to-top {
    transition: none;
  }
  .back-to-top:hover {
    transform: none;
  }
}