.fab{
  position:fixed;right:36rpx;bottom:calc(190rpx + env(safe-area-inset-bottom));
  width:108rpx;height:108rpx;border-radius:var(--r-md);
  background:var(--cta);
  color:#fff;
  display:flex;align-items:center;justify-content:center;
  box-shadow:var(--sd-2);
  z-index:60;
}
.fab:active{transform:scale(.96)}