/* ── RESPONSIVE ── */
@media(max-width:900px){
  nav{padding:0 20px}
  .hero,.proj-sec,.about-wrap,.ct-sec{padding-left:20px;padding-right:20px}
  .proj-grid{grid-template-columns:1fr}
  .approach-row{grid-template-columns:28px 1fr;gap:12px}
  .approach-metric{display:none}
  .metric-strip,.st4,.st3,.cs-meta{grid-template-columns:repeat(2,1fr)}
  .ms-item:nth-child(2){border-right:none}
  .sk-grid{grid-template-columns:1fr 1fr}
  .sk-card:nth-child(2n){border-right:none}
  .cs-hd,.cs-body,.exp-sec,.sk-sec{padding-left:20px;padding-right:20px}
  .cs-meta .cs-mi:nth-child(2n){border-right:none}
  .exp-item{grid-template-columns:1fr;gap:5px}
  .quotes,.neg-grid,.rq-grid,.ba-grid{grid-template-columns:1fr}
  .ba-card{border-right:none;border-bottom:1px solid var(--border)}
  .case-nav{grid-template-columns:1fr 1fr}
  .cn-item:nth-child(2n){border-right:none}
  .hero-scroll{display:none}
  footer{padding:14px 20px}
  .impact-row{flex-direction:column}
  .impact-chip{border-right:none;border-bottom:1px solid var(--border)}
}