.back-to-top{position:fixed;bottom:2rem;right:2rem;width:44px;height:44px;display:flex;align-items:center;justify-content:center;background:var(--primary);color:#fff;border-radius:12px;opacity:0;visibility:hidden;transform:translateY(20px);transition:var(--transition);z-index:999;box-shadow:0 4px 16px var(--primary-glow);text-decoration:none}.back-to-top.visible{opacity:1;visibility:visible;transform:translateY(0)}.back-to-top:hover{transform:translateY(-4px);color:#fff}