.scroll-to-top-button {
    position: fixed;
    right: 1rem;
    bottom: 4.75rem;
    z-index: 9998;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 3rem;
    height: 3rem;
    border: 0;
    border-radius: 9999px;
    background: var(--navigation-background-color, #f5ae72);
    color: var(--navigation-text-color, #111827);
    box-shadow: 0 12px 28px rgba(15, 23, 42, 0.24);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transform: translate3d(0, 10px, 0) scale(0.92);
    backface-visibility: hidden;
    will-change: opacity, transform;
    transition: opacity .24s ease, transform .28s ease, visibility .24s ease, box-shadow .24s ease;
}

.scroll-to-top-button--mobile {
    bottom: calc(5.75rem + env(safe-area-inset-bottom, 0px));
}

.scroll-to-top-button.is-visible {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: translate3d(0, 0, 0) scale(1);
}

.scroll-to-top-button:hover {
    background: var(--navigation-highlight-color, #0057c8);
    color: var(--navigation-background-color, #e65100);
    transform: translateY(-2px) scale(1.05);
    box-shadow: 0 16px 34px rgba(15, 23, 42, 0.28);
}

.scroll-to-top-button svg {
    display: block;
    width: 1.1rem;
    height: 1.1rem;
    transition: transform .24s ease;
}

.scroll-to-top-button:hover svg {
    transform: translateY(-2px);
}

@media (prefers-reduced-motion: reduce) {
    .scroll-to-top-button,
    .scroll-to-top-button svg {
        transition: none;
    }
}

@media (max-width: 640px) {
    .scroll-to-top-button {
        bottom: calc(5.75rem + env(safe-area-inset-bottom, 0px));
    }
}

@media (hover: none) and (pointer: coarse) {
    .scroll-to-top-button,
    .scroll-to-top-button.is-visible,
    .scroll-to-top-button:hover {
        transform: none;
    }

    .scroll-to-top-button:hover svg {
        transform: none;
    }
}