/* BACK TO TOP */
        .back-to-top {
            position: fixed;
            bottom: 2rem;
            right: 2rem;
            width: 46px;
            height: 46px;
            background: var(--oak);
            color: #fff;
            border: none;
            border-radius: var(--radius-sm);
            font-size: 1.15rem;
            cursor: pointer;
            opacity: 0;
            transform: translateY(20px);
            pointer-events: none;
            transition: var(--transition);
            z-index: 999;
            box-shadow: var(--shadow-md);
        }
        .back-to-top.visible {
            opacity: 1;
            transform: translateY(0);
            pointer-events: auto;
        }
        .back-to-top:hover {
            background: var(--oak-deep);
            transform: translateY(-4px);
        }