/**
 * File: assets/css/frontend/shared/back-to-top.css
 * Purpose: Styles the site-wide floating back-to-top button.
 * Scope: Button appearance and show/hide transition only.
 * Related PHP: src/Frontend/Shared/BackToTop.php
 * Related JS: assets/js/frontend/shared/back-to-top.js
 * Package: HyperDAF Pro
 */
.hdf-back-to-top {
    position: fixed;
    right: 1.5rem;
    bottom: 1.5rem;
    z-index: 60;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 3rem;
    height: 3rem;
    padding: 0;
    border: 0;
    border-radius: 50%;
    background: var(--hdf-blog-accent, #1e7a4f);
    color: #fff;
    cursor: pointer;
    box-shadow: 0 0.75rem 1.75rem -0.625rem rgb(11 31 58 / 0.45);
    opacity: 0;
    visibility: hidden;
    transform: translateY(0.75rem);
    transition: opacity 0.25s ease, transform 0.25s ease, visibility 0.25s ease, background 0.2s ease;
}
.hdf-back-to-top .hdf-icon {
    width: 1.375rem;
    height: 1.375rem;
}
.hdf-back-to-top.is-visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}
.hdf-back-to-top:hover {
    background: var(--hdf-blog-text, #0b1f3a);
}
.hdf-back-to-top:focus-visible {
    outline: 2px solid var(--hdf-blog-text, #0b1f3a);
    outline-offset: 2px;
}
@media (max-width: 40rem) {
    .hdf-back-to-top {
        right: 1rem;
        bottom: 1rem;
        width: 2.75rem;
        height: 2.75rem;
    }
}
@media (prefers-reduced-motion: reduce) {
    .hdf-back-to-top {
        transition: none;
    }
}