/* Botão voltar ao topo (parte de style.css) */
/* ============================================================
   VOLTAR AO TOPO — anel de progresso (como em surfaceconcept.pt)
   ============================================================ */
.scroll-top {
    position: fixed;
    right: 30px;
    bottom: 30px;
    width: 50px;
    height: 50px;
    padding: 0;
    border: 0;
    border-radius: 50%;
    background: none;
    cursor: pointer;
    z-index: 900;
    opacity: 0;
    visibility: hidden;
    transform: translateY(45px);
    transition: 300ms linear;
}
.scroll-top.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}
/* círculo base + seta */
.scroll-top::after {
    content: "";
    position: absolute;
    inset: 0;
    border: 2px solid var(--verde);
    border-radius: 50%;
    background:
        linear-gradient(var(--verde), var(--verde)) 50% 50% / 2px 16px no-repeat;
    -webkit-mask: none;
    pointer-events: none;
}
.scroll-top::before {
    content: "";
    position: absolute;
    left: 50%;
    top: 50%;
    width: 10px;
    height: 10px;
    border-left: 2px solid var(--verde);
    border-top: 2px solid var(--verde);
    transform: translate(-50%, -75%) rotate(45deg);
    z-index: 1;
    pointer-events: none;
}
.scroll-top svg {
    display: block;
    border-radius: 50%;
    background: var(--superficie);
    color: var(--verde);
}
.scroll-top svg path {
    fill: none;
    stroke: var(--verde);
    stroke-width: 20px;
    box-sizing: border-box;
    transition: stroke-dashoffset 400ms linear;
}
.scroll-top:hover::after,
.scroll-top:hover::before { border-color: var(--verde-escuro); }
.scroll-top:focus-visible { outline: 2px solid var(--verde); outline-offset: 3px; }
body.dark .scroll-top svg path { stroke: var(--verde-claro); }
body.dark .scroll-top::after,
body.dark .scroll-top::before { border-color: var(--verde-claro); }
body.dark .scroll-top::after { background-image: linear-gradient(var(--verde-claro), var(--verde-claro)); }
@media (prefers-reduced-motion: reduce) {
    .scroll-top, .scroll-top svg path { transition: none; }
}
@media print { .scroll-top { display: none !important; } }