:root{
  --bg:#ffffff; --panel:#f6f8fb; --ink:#0f172a; --muted:#516074;
  --line:#e4e9f0; --accent:#1d4ed8; --accent-d:#1733a8;
  --dark:#0b1220; --dark2:#111b2e; --radius:14px; --wrap:1120px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:"Inter",system-ui,-apple-system,Segoe UI,Roboto,sans-serif;
  color:var(--ink);background:var(--bg);line-height:1.6;-webkit-font-smoothing:antialiased}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;display:block}
.wrap{max-width:var(--wrap);margin:0 auto;padding:0 24px}

/* header / nav */
header.site{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.92);
  backdrop-filter:blur(8px);border-bottom:1px solid var(--line)}
.nav{display:flex;align-items:center;justify-content:space-between;height:64px}
.brand{font-weight:800;letter-spacing:.5px;font-size:1.15rem;color:var(--ink)}
.brand span{color:var(--accent)}
.menu{display:flex;gap:4px;align-items:center;list-style:none;margin:0;padding:0}
.menu>li{position:relative}
.menu>li>a{display:block;padding:10px 14px;border-radius:8px;color:var(--ink);font-weight:500;font-size:.95rem}
.menu>li>a:hover,.menu>li>a.active{background:var(--panel);text-decoration:none;color:var(--accent)}
.drop{position:absolute;top:100%;left:0;min-width:220px;background:#fff;border:1px solid var(--line);
  border-radius:12px;box-shadow:0 12px 30px rgba(15,23,42,.12);padding:6px;display:none}
.menu>li:hover .drop{display:block}
.drop a{display:block;padding:9px 12px;border-radius:8px;color:var(--ink);font-size:.92rem}
.drop a:hover{background:var(--panel);text-decoration:none;color:var(--accent)}
.navtoggle{display:none;background:none;border:0;font-size:1.5rem;cursor:pointer;color:var(--ink)}

/* hero */
.hero{background:linear-gradient(160deg,var(--dark),var(--dark2));color:#eef2f8;padding:84px 0}
.hero h1{font-size:clamp(2.1rem,5vw,3.4rem);line-height:1.1;margin:0 0 16px;letter-spacing:-.5px}
.hero p.lede{font-size:1.2rem;color:#b9c4d6;max-width:640px;margin:0 0 28px}
.kicker{text-transform:uppercase;letter-spacing:2px;font-size:.78rem;color:#7f9bd6;font-weight:700;margin-bottom:14px}
.hero-img{margin-top:40px;border-radius:var(--radius);overflow:hidden;border:1px solid rgba(255,255,255,.08)}

/* buttons */
.btn{display:inline-block;background:var(--accent);color:#fff;padding:12px 22px;border-radius:10px;
  font-weight:600;font-size:.95rem;border:1px solid var(--accent)}
.btn:hover{background:var(--accent-d);text-decoration:none}
.btn.ghost{background:transparent;color:#eef2f8;border-color:rgba(255,255,255,.35)}
.btn.ghost:hover{background:rgba(255,255,255,.08)}
.btns{display:flex;gap:12px;flex-wrap:wrap}

/* sections */
section.block{padding:64px 0}
section.block.alt{background:var(--panel);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.eyebrow{text-transform:uppercase;letter-spacing:1.5px;font-size:.76rem;color:var(--accent);font-weight:700;margin-bottom:10px}
h2.sec{font-size:clamp(1.6rem,3.5vw,2.2rem);margin:0 0 10px;letter-spacing:-.3px}
.sub{color:var(--muted);max-width:680px;margin:0 0 32px;font-size:1.05rem}
.tag{display:inline-block;font-size:.72rem;font-weight:700;letter-spacing:1px;text-transform:uppercase;
  padding:4px 10px;border-radius:999px;margin-bottom:18px}
.tag.current{background:#dbeafe;color:#1733a8}
.tag.legacy{background:#eceff3;color:#516074}

/* cards */
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:20px}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:26px;
  transition:transform .15s ease,box-shadow .15s ease}
.card:hover{transform:translateY(-3px);box-shadow:0 14px 34px rgba(15,23,42,.10)}
.card h3{margin:0 0 8px;font-size:1.2rem}
.card p{color:var(--muted);margin:0 0 16px;font-size:.97rem}
.card .more{font-weight:600}

/* gallery */
.gallery{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:18px}
.gallery figure{margin:0;background:#fff;border:1px solid var(--line);border-radius:var(--radius);overflow:hidden}
.gallery img{width:100%;height:220px;object-fit:cover;background:#f1f4f8}
.gallery figcaption{padding:12px 16px;font-size:.88rem;color:var(--muted)}

/* video */
.video{position:relative;padding-bottom:56.25%;height:0;border-radius:var(--radius);overflow:hidden;border:1px solid var(--line);background:#000}
.video iframe{position:absolute;top:0;left:0;width:100%;height:100%;border:0}

/* downloads */
.dl{list-style:none;padding:0;margin:0;display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:12px}
.dl a{display:flex;align-items:center;gap:12px;background:#fff;border:1px solid var(--line);
  border-radius:10px;padding:14px 16px;color:var(--ink);font-weight:500}
.dl a:hover{border-color:var(--accent);text-decoration:none;background:var(--panel)}
.dl .ext{font-size:.72rem;font-weight:700;color:#fff;background:var(--accent);border-radius:6px;padding:3px 7px}

/* prose */
.prose p{color:var(--muted);font-size:1.05rem;max-width:720px}

/* footer */
footer.site{background:var(--dark);color:#aebbd0;padding:40px 0;margin-top:20px}
footer.site .wrap{display:flex;justify-content:space-between;gap:20px;flex-wrap:wrap;align-items:center}
footer.site a{color:#cdd8ea}
.note{font-size:.9rem;color:#7f8ca3}

@media(max-width:760px){
  .navtoggle{display:block}
  .menu{position:absolute;top:64px;left:0;right:0;flex-direction:column;align-items:stretch;
    background:#fff;border-bottom:1px solid var(--line);padding:8px;display:none}
  .menu.open{display:flex}
  .menu>li>a{padding:12px}
  .drop{position:static;display:block;border:0;box-shadow:none;padding:0 0 0 14px;min-width:0}
  .menu>li:hover .drop{display:block}
}

/* in-page sub-nav (combined product page) */
.subnav{background:var(--panel);border-bottom:1px solid var(--line);position:sticky;top:63px;z-index:40}
.subnav .wrap{display:flex;gap:6px;padding:10px 24px;overflow-x:auto}
.subnav a{white-space:nowrap;padding:8px 14px;border-radius:8px;font-size:.9rem;font-weight:600;color:var(--muted)}
.subnav a:hover{background:#fff;color:var(--accent);text-decoration:none}

/* grouped sub-sections (Diagrams / Whitepapers / Patents) */
.grouphead{font-size:1rem;font-weight:700;letter-spacing:.3px;color:var(--ink);
  margin:38px 0 16px;padding-bottom:8px;border-bottom:1px solid var(--line)}
.grouphead.first{margin-top:8px}

/* video grid (side-by-side embeds) */
.videos{display:grid;grid-template-columns:repeat(auto-fit,minmax(320px,1fr));gap:18px}

/* click-to-enlarge lightbox */
.gallery img,img.zoomable{cursor:zoom-in}
.lightbox{position:fixed;inset:0;background:rgba(11,18,32,.93);display:none;
  align-items:center;justify-content:center;z-index:200;padding:24px;cursor:zoom-out}
.lightbox.open{display:flex}
.lightbox img{max-width:96vw;max-height:92vh;width:auto;height:auto;border-radius:8px;
  box-shadow:0 20px 60px rgba(0,0,0,.55);cursor:default}
.lightbox .x{position:fixed;top:14px;right:22px;color:#fff;font-size:2.2rem;line-height:1;
  background:none;border:0;cursor:pointer}

/* sub-subsection heads (Embedded / iOS under Prototype) */
.subhead{font-size:1.05rem;font-weight:700;color:var(--ink);margin:30px 0 8px}