/* PKN naming and shared navigation. Existing page contracts remain intact. */
:root{--accent:#485bd4;--accent-soft:#edf0ff;--ink:#202b43;--canvas:#f5f7fb;--line:#dfe5ee}
.brand{align-items:flex-start;gap:9px}.brand .mark{width:38px;height:38px;flex-shrink:0;background:#485bd4;letter-spacing:-.05em;border-radius:10px;font-size:12px;margin-top:2px}.brand>div{min-width:0}.brand b{font-size:14px;letter-spacing:.01em}.brand small{display:block;font-size:10px;line-height:1.65}.brand .brand-full{font:9px/1.6 -apple-system,"Segoe UI",sans-serif;color:#74809a;white-space:normal;max-width:158px}
#nav a.on .area-icon{background:var(--accent);border-color:var(--accent);color:white}#nav a:hover{background:#f2f4fc}#nav a.on{background:var(--accent-soft);color:var(--accent)}
.top-right{min-width:0}#subnav{min-width:0}.guide-link{white-space:nowrap}.top-links{display:flex;gap:4px;align-items:center}
@media(max-width:900px){.top-right .top-links{align-self:flex-end}}
.pkn-eyebrow{font-size:11px;letter-spacing:.035em;color:var(--accent);font-weight:600}.pkn-start{border:1px solid var(--line);background:#fff;border-radius:12px;padding:24px;margin-bottom:20px}.pkn-start h1{font-size:24px;line-height:1.5;letter-spacing:-.02em;margin:6px 0}.pkn-start p{color:var(--muted);font-size:13px;margin:4px 0 20px;line-height:1.8}.pkn-start-links{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}.pkn-start-links a{display:flex;flex-direction:column;gap:5px;border:1px solid var(--line);border-radius:8px;background:#f8f9fd;padding:16px;text-decoration:none;color:var(--ink)}.pkn-start-links a:hover{border-color:var(--accent);background:var(--accent-soft)}.pkn-start-links b{font-size:14px}.pkn-start-links span{font-size:12px;color:var(--muted)}.pkn-artifact-stages{background:#fff;border:1px solid var(--line);border-radius:9px;padding:15px 18px;margin-bottom:18px}.pkn-artifact-stages summary{font-size:13px;font-weight:600;cursor:pointer}.pkn-artifact-stages .steps{margin-top:16px}
@media(max-width:700px){.pkn-start{padding:18px}.pkn-start h1{font-size:21px}.pkn-start-links{grid-template-columns:1fr;gap:8px}.pkn-start-links a{padding:13px}.pkn-artifact-stages{padding:14px}.pkn-artifact-stages .steps{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto!important}}