.sb-back-to-top {
  position: fixed;
  right: max(20px, env(safe-area-inset-right));
  bottom: max(20px, env(safe-area-inset-bottom));
  z-index: 1000;
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid #cc3333;
  border-radius: 50%;
  color: #cc3333;
  background: #fff;
  box-shadow: 0 2px 10px #00000012;
  cursor: pointer;
}
.sb-back-to-top[hidden] { display: none; }
.sb-back-to-top:hover { color: #fff; background: #cc3333; }
.sb-back-to-top:focus-visible { outline: 3px solid #cc3333; outline-offset: 4px; }
@media (max-width: 750px) {
  .sb-back-to-top { right: max(12px, env(safe-area-inset-right)); bottom: max(12px, env(safe-area-inset-bottom)); }
  body { padding-bottom: 68px; }
}