/* Botão flutuante "voltar ao topo" — compartilhado em todo o site */
.back-to-top{position:fixed;right:20px;bottom:20px;width:46px;height:46px;border-radius:50%;background:#E3262E;color:#fff;border:none;display:flex;align-items:center;justify-content:center;cursor:pointer;box-shadow:0 10px 26px rgba(7,28,57,.28);opacity:0;visibility:hidden;transform:translateY(14px);transition:opacity .3s,transform .3s,visibility .3s,background .3s;z-index:200}
.back-to-top.show{opacity:1;visibility:visible;transform:translateY(0)}
.back-to-top:hover{background:#ff363f;transform:translateY(-3px)}
.back-to-top:active{transform:translateY(-1px)}
.back-to-top svg{width:20px;height:20px;pointer-events:none}
@media(max-width:768px){
  .back-to-top{right:16px;bottom:16px;width:42px;height:42px}
  .back-to-top svg{width:18px;height:18px}
}