.shell{grid-template-columns:260px 1fr;min-height:100vh;display:grid}.sidebar{color:#f9fafb;background:#17202a;padding:24px}.brand{color:#f9fafb;margin-bottom:28px;font-size:20px;font-weight:700;display:inline-flex}.sidebar nav{gap:8px;display:grid}.sidebar a{color:#eef2f7;border-radius:6px;padding:10px 12px}.sidebar a:hover,.sidebar a:focus,.sidebar a.active{background:#273445}.sidebar a.active{border-left:3px solid #8bd3f7}.content{padding:40px}@media (max-width:760px){.shell{grid-template-columns:1fr}.sidebar{padding:18px}}