/* =====================================================================
   Flow Meter Reference — industrial / precision-engineering design system
   Custom CSS (no UI framework). Google Fonts + inline SVG icons only.
   Content is ALWAYS visible: no visibility is gated on JavaScript.
   ===================================================================== */

:root{
  --navy-900:#0c2233;
  --navy-800:#0e2a3f;
  --navy-700:#123a56;
  --steel-600:#14507a;
  --steel-500:#1a6aa8;
  --steel-400:#3d8bc4;
  --amber-600:#d9741a;
  --amber-500:#f5a623;
  --amber-100:#fdeccd;
  --ink:#1a2733;
  --slate:#4b5b68;
  --muted:#6d7d8a;
  --line:#d9e0e6;
  --line-strong:#c2ccd4;
  --bg:#ffffff;
  --bg-alt:#f4f6f8;
  --bg-steel:#eef2f5;
  --ok:#1f7a4d;
  --shadow-sm:0 1px 2px rgba(12,34,51,.06),0 2px 6px rgba(12,34,51,.05);
  --shadow-md:0 6px 20px rgba(12,34,51,.10);
  --radius:6px;
  --maxw:1160px;
  --mono:"IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,monospace;
  --head:"Barlow Semi Condensed","Barlow",system-ui,sans-serif;
  --body:"Barlow","Segoe UI",system-ui,-apple-system,sans-serif;
}

*,*::before,*::after{box-sizing:border-box;}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%;}
body{
  margin:0;font-family:var(--body);color:var(--ink);background:var(--bg);
  font-size:18px;line-height:1.65;font-weight:400;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;height:auto;display:block;}
a{color:var(--steel-600);text-decoration:none;}
a:hover{color:var(--amber-600);text-decoration:underline;text-underline-offset:2px;}

/* Safeguard: content never hidden waiting on JS (defensive; no AOS used). */
[data-aos]{opacity:1 !important;transform:none !important;}

.container{max-width:var(--maxw);margin:0 auto;padding:0 22px;}

/* ---------- Blueprint background accents ---------- */
.blueprint{
  background-color:var(--navy-800);
  background-image:
    linear-gradient(rgba(255,255,255,.05) 1px,transparent 1px),
    linear-gradient(90deg,rgba(255,255,255,.05) 1px,transparent 1px);
  background-size:26px 26px;
}

/* ---------- Utility top bar ---------- */
.utilbar{background:var(--navy-900);color:#a9c2d4;font-family:var(--mono);
  font-size:12.5px;letter-spacing:.04em;}
.utilbar .container{display:flex;justify-content:space-between;align-items:center;
  min-height:34px;gap:16px;flex-wrap:wrap;}
.utilbar span{display:inline-flex;align-items:center;gap:7px;}
.utilbar .ico{width:14px;height:14px;fill:var(--amber-500);flex:none;}

/* ---------- Header ---------- */
.site-header{position:sticky;top:0;z-index:50;background:#fff;
  border-bottom:1px solid var(--line);box-shadow:var(--shadow-sm);}
.site-header .container{display:flex;align-items:center;justify-content:space-between;
  min-height:70px;gap:18px;}
.brand{display:flex;align-items:center;gap:12px;font-family:var(--head);
  font-weight:700;color:var(--navy-800);letter-spacing:.01em;}
.brand:hover{text-decoration:none;color:var(--navy-800);}
.brand .mark{width:40px;height:40px;flex:none;border-radius:5px;
  background:linear-gradient(150deg,var(--steel-600),var(--navy-800));
  display:grid;place-items:center;box-shadow:var(--shadow-sm);}
.brand .mark svg{width:24px;height:24px;fill:none;stroke:var(--amber-500);stroke-width:2.1;}
.brand .name{font-size:22px;line-height:1;text-transform:uppercase;}
.brand .name small{display:block;font-family:var(--mono);font-weight:500;
  font-size:10.5px;letter-spacing:.16em;color:var(--muted);margin-top:3px;
  text-transform:uppercase;}

.nav{display:flex;align-items:center;gap:2px;}
.nav a{font-family:var(--head);font-weight:600;font-size:16px;color:var(--navy-700);
  text-transform:uppercase;letter-spacing:.03em;padding:9px 12px;border-radius:5px;
  white-space:nowrap;}
.nav a:hover{background:var(--bg-steel);color:var(--steel-600);text-decoration:none;}
.nav a[aria-current="page"]{color:var(--amber-600);box-shadow:inset 0 -3px 0 var(--amber-500);}

.nav-toggle{display:none;background:var(--navy-800);border:0;border-radius:5px;
  width:46px;height:42px;cursor:pointer;padding:0;}
.nav-toggle span,.nav-toggle span::before,.nav-toggle span::after{
  content:"";display:block;width:22px;height:2px;background:#fff;margin:0 auto;
  position:relative;transition:.2s;}
.nav-toggle span::before{position:absolute;top:-6px;}
.nav-toggle span::after{position:absolute;top:6px;}

/* ---------- Page header / eyebrow ---------- */
.page-head{padding:34px 0 8px;}
.eyebrow{font-family:var(--mono);font-size:12.5px;font-weight:500;letter-spacing:.2em;
  text-transform:uppercase;color:var(--steel-500);display:inline-flex;align-items:center;gap:9px;}
.eyebrow::before{content:"";width:26px;height:2px;background:var(--amber-500);display:inline-block;}
.breadcrumb{font-family:var(--mono);font-size:12.5px;color:var(--muted);margin:0 0 14px;
  letter-spacing:.02em;}
.breadcrumb a{color:var(--muted);}
.breadcrumb a:hover{color:var(--steel-600);}

/* ---------- Hero (home) ---------- */
.hero{color:#eaf2f8;position:relative;overflow:hidden;border-bottom:3px solid var(--amber-500);}
.hero::after{content:"";position:absolute;inset:0;
  background:linear-gradient(120deg,rgba(10,28,42,.94) 0%,rgba(12,34,51,.72) 46%,rgba(12,34,51,.30) 100%);}
.hero .hero-img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;}
.hero .container{position:relative;z-index:2;padding:76px 22px 70px;max-width:var(--maxw);}
.hero .eyebrow{color:var(--amber-500);}
.hero h1{color:#fff;font-size:clamp(2.3rem,4.6vw,3.5rem);margin:14px 0 16px;max-width:16ch;}
.hero p{font-size:1.24rem;max-width:60ch;color:#d6e4ee;margin:0 0 26px;}
.hero-cta{display:flex;gap:14px;flex-wrap:wrap;}

/* ---------- Buttons ---------- */
.btn{display:inline-flex;align-items:center;gap:9px;font-family:var(--head);font-weight:600;
  text-transform:uppercase;letter-spacing:.04em;font-size:15.5px;padding:12px 22px;border-radius:5px;
  cursor:pointer;border:2px solid transparent;transition:.16s;}
.btn-primary{background:var(--amber-500);color:var(--navy-900);}
.btn-primary:hover{background:var(--amber-600);color:#fff;text-decoration:none;transform:translateY(-1px);}
.btn-ghost{border-color:rgba(255,255,255,.5);color:#fff;}
.btn-ghost:hover{background:#fff;color:var(--navy-800);text-decoration:none;}

/* ---------- Main / article layout ---------- */
main{display:block;}
.section{padding:30px 0 56px;}
.article{max-width:820px;margin:0 auto;}
.article.wide{max-width:960px;}

.prose{font-size:1.06rem;}
.prose h1{font-family:var(--head);font-weight:700;font-size:clamp(2rem,3.6vw,2.75rem);
  line-height:1.1;margin:.2em 0 .5em;color:var(--navy-800);letter-spacing:.005em;}
.page-head h1{margin-top:6px;}
.prose h2{font-family:var(--head);font-weight:700;font-size:1.62rem;color:var(--navy-700);
  margin:1.9em 0 .55em;padding-bottom:.28em;border-bottom:1px solid var(--line);letter-spacing:.005em;}
.prose h3{font-family:var(--head);font-weight:600;font-size:1.28rem;color:var(--navy-700);margin:1.5em 0 .4em;}
.prose p{margin:0 0 1.1em;}
.prose .lead{font-size:1.24rem;line-height:1.55;color:var(--slate);font-weight:400;margin-bottom:1.3em;}
.prose ul,.prose ol{margin:0 0 1.2em;padding-left:1.35em;}
.prose li{margin:.4em 0;}
.prose ul li::marker{color:var(--amber-600);}
.prose strong{color:var(--navy-800);font-weight:600;}
.prose a{border-bottom:1px solid rgba(20,80,122,.35);}
.prose a:hover{border-bottom-color:var(--amber-600);}

/* editorial independence note */
.editorial-note{font-size:.92rem;line-height:1.5;color:var(--slate);
  background:var(--bg-alt);border-left:3px solid var(--steel-400);
  padding:12px 16px;border-radius:0 var(--radius) var(--radius) 0;margin:0 0 1.4em;font-style:italic;}

/* figures / images */
figure{margin:1.6em 0;}
figure img{border-radius:var(--radius);box-shadow:var(--shadow-md);width:100%;}
figure.hero-fig img{border:1px solid var(--line);}
figcaption{font-family:var(--mono);font-size:12px;color:var(--muted);margin-top:9px;
  letter-spacing:.02em;padding-left:12px;border-left:2px solid var(--amber-500);}

/* At-a-glance spec card */
.spec-card{background:var(--navy-800);color:#dce8f0;border-radius:var(--radius);
  padding:20px 22px;margin:0 0 1.6em;box-shadow:var(--shadow-md);
  background-image:linear-gradient(rgba(255,255,255,.03) 1px,transparent 1px),
    linear-gradient(90deg,rgba(255,255,255,.03) 1px,transparent 1px);background-size:22px 22px;}
.spec-card .spec-title{display:block;font-family:var(--mono);font-size:12px;font-weight:500;
  letter-spacing:.2em;text-transform:uppercase;color:var(--amber-500);margin-bottom:12px;}
.spec-card dl{display:grid;grid-template-columns:auto 1fr;gap:9px 18px;margin:0;font-size:.96rem;}
.spec-card dt{font-family:var(--mono);font-size:12px;letter-spacing:.03em;text-transform:uppercase;
  color:#89a7bd;align-self:center;}
.spec-card dd{margin:0;color:#fff;font-weight:500;}

/* tables */
.prose table{width:100%;border-collapse:collapse;margin:1.4em 0;font-size:.95rem;
  box-shadow:var(--shadow-sm);border-radius:var(--radius);overflow:hidden;}
.prose thead th{background:var(--navy-700);color:#fff;font-family:var(--head);font-weight:600;
  text-transform:uppercase;letter-spacing:.03em;font-size:.86rem;text-align:left;padding:11px 13px;}
.prose tbody td{padding:10px 13px;border-bottom:1px solid var(--line);vertical-align:top;}
.prose tbody tr:nth-child(even){background:var(--bg-alt);}
.prose tbody tr:hover{background:var(--amber-100);}

/* ---------- Home: feature/nav grids ---------- */
.band{padding:52px 0;}
.band-alt{background:var(--bg-alt);border-top:1px solid var(--line);border-bottom:1px solid var(--line);}
.band .container>.eyebrow{margin-bottom:8px;}
.band h2.band-title{font-family:var(--head);font-weight:700;font-size:2rem;color:var(--navy-800);
  margin:.1em 0 .1em;}
.band .intro{color:var(--slate);max-width:64ch;margin:0 0 26px;font-size:1.08rem;}

.grid{display:grid;gap:20px;}
.grid-3{grid-template-columns:repeat(3,1fr);}
.grid-2{grid-template-columns:repeat(2,1fr);}
.grid-4{grid-template-columns:repeat(4,1fr);}

.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);
  padding:24px 22px;box-shadow:var(--shadow-sm);transition:.16s;position:relative;
  border-top:3px solid var(--steel-500);}
.card:hover{box-shadow:var(--shadow-md);transform:translateY(-3px);border-top-color:var(--amber-500);}
.card .ico{width:34px;height:34px;stroke:var(--steel-600);fill:none;stroke-width:1.8;margin-bottom:12px;}
.card h3{font-family:var(--head);font-weight:700;font-size:1.24rem;color:var(--navy-800);margin:0 0 8px;}
.card h3 a{color:inherit;}
.card h3 a:hover{color:var(--steel-600);text-decoration:none;}
.card p{margin:0;color:var(--slate);font-size:.98rem;}
.card .go{display:inline-block;margin-top:12px;font-family:var(--mono);font-size:12.5px;
  letter-spacing:.06em;text-transform:uppercase;color:var(--amber-600);}

.familytags{display:flex;flex-wrap:wrap;gap:10px;margin-top:6px;}
.familytags a{font-family:var(--head);font-weight:600;text-transform:uppercase;letter-spacing:.03em;
  font-size:15px;background:#fff;border:1px solid var(--line-strong);border-radius:40px;
  padding:8px 18px;color:var(--navy-700);}
.familytags a:hover{background:var(--navy-800);color:#fff;border-color:var(--navy-800);text-decoration:none;}

/* contact form */
.contact-form{display:grid;gap:16px;max-width:560px;margin:1.2em 0 0;
  background:var(--bg-alt);border:1px solid var(--line);border-radius:var(--radius);padding:24px;}
.contact-form label{display:grid;gap:6px;font-family:var(--head);font-weight:600;
  text-transform:uppercase;letter-spacing:.03em;font-size:13.5px;color:var(--navy-700);}
.contact-form input,.contact-form select,.contact-form textarea{
  font-family:var(--body);font-size:16px;padding:11px 13px;border:1px solid var(--line-strong);
  border-radius:5px;background:#fff;color:var(--ink);width:100%;}
.contact-form input:focus,.contact-form select:focus,.contact-form textarea:focus{
  outline:2px solid var(--steel-400);border-color:var(--steel-500);}
.contact-form .btn{justify-self:start;}

/* ---------- Footer ---------- */
.site-footer{color:#b9ccd9;margin-top:20px;}
.site-footer .container{padding-top:52px;padding-bottom:26px;}
.foot-grid{display:grid;grid-template-columns:1.5fr 1fr 1fr 1fr;gap:34px;}
.foot-brand .brand{color:#fff;margin-bottom:14px;}
.foot-brand .brand .name{color:#fff;}
.foot-brand p{font-size:.94rem;color:#93aabb;max-width:38ch;}
.foot-col h4{font-family:var(--mono);font-size:12px;font-weight:500;letter-spacing:.18em;
  text-transform:uppercase;color:var(--amber-500);margin:0 0 14px;}
.foot-col ul{list-style:none;margin:0;padding:0;}
.foot-col li{margin:.5em 0;}
.foot-col a{color:#b9ccd9;font-size:.96rem;}
.foot-col a:hover{color:#fff;text-decoration:none;}
.foot-bottom{border-top:1px solid rgba(255,255,255,.12);margin-top:38px;padding-top:20px;
  display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap;
  font-size:.86rem;color:#7d95a7;font-family:var(--mono);letter-spacing:.02em;}
.foot-disclaimer{max-width:100%;color:#7d95a7;font-size:.82rem;line-height:1.55;
  margin-top:14px;font-family:var(--body);letter-spacing:0;}

/* ---------- 404 ---------- */
.notfound{min-height:56vh;display:grid;place-items:center;text-align:center;padding:60px 22px;}
.notfound .code{font-family:var(--head);font-weight:700;font-size:clamp(4rem,14vw,8rem);
  line-height:1;color:var(--navy-800);letter-spacing:.02em;}
.notfound .code span{color:var(--amber-500);}

/* ---------- Responsive ---------- */
@media (max-width:900px){
  .foot-grid{grid-template-columns:1fr 1fr;gap:26px;}
  .grid-4{grid-template-columns:repeat(2,1fr);}
  .grid-3{grid-template-columns:repeat(2,1fr);}
}
@media (max-width:760px){
  body{font-size:17px;}
  .nav-toggle{display:block;}
  .nav{position:absolute;top:70px;left:0;right:0;flex-direction:column;align-items:stretch;
    background:#fff;border-bottom:1px solid var(--line);box-shadow:var(--shadow-md);
    padding:10px 14px;gap:2px;display:none;}
  .nav.open{display:flex;}
  .nav a{padding:12px 10px;font-size:17px;}
  .nav a[aria-current="page"]{box-shadow:inset 3px 0 0 var(--amber-500);}
  .grid-3,.grid-2,.grid-4{grid-template-columns:1fr;}
  .foot-grid{grid-template-columns:1fr;}
  .hero .container{padding:54px 22px 48px;}
  .utilbar{display:none;}
}
@media (max-width:420px){
  .brand .name{font-size:19px;}
}