.section{margin-bottom:4rem;padding:2rem;background:rgba(255,255,255,.02);border-radius:var(--border-radius);border:1px solid rgba(255,255,255,.05);transition:var(--transition);position:relative;overflow:hidden}.section::before{content:"";position:absolute;top:0;left:0;width:100%;height:2px;background:linear-gradient(90deg,var(--primary-color),var(--secondary-color),var(--accent-color));opacity:0;transition:opacity .3s ease}.section:hover::before{opacity:1}.section:hover{background:rgba(255,255,255,.05);transform:translateY(-5px);box-shadow:0 10px 30px rgba(0,0,0,.3)}.back-to-top.visible{opacity:1;transform:translateY(0)}@media (max-width:768px){.section{padding:1.5rem;margin-bottom:2rem}}