/* ==========================================================================
   HVAC Air Solutions Inc — Design System
   Signature motif: the "system line" — a schematic duct/pipe run with
   node markers, echoing mechanical drawings & blueprint schematics.
   ========================================================================== */

:root{
  --bg:            #F2F4F1;
  --bg-alt:        #E9ECE7;
  --panel:         #FFFFFF;
  --ink:           #12181D;
  --ink-soft:      #4B5560;
  --steel:         #2E4B5C;
  --steel-dark:    #16232B;
  --steel-deeper:  #0E1519;
  --copper:        #BE7A3D;
  --copper-light:  #E3A868;
  --ice:           #7FA7C4;
  --line:          #D3D7CF;
  --line-dark:     rgba(255,255,255,0.14);
  --ok:            #5C8A5C;

  --font-display: "Barlow Condensed", "Arial Narrow", sans-serif;
  --font-body:    "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono:    "IBM Plex Mono", "Courier New", monospace;

  --radius: 3px;
  --container: 1180px;
}

*,*::before,*::after{ box-sizing:border-box; }
html{ scroll-behavior:smooth; }
body{
  margin:0;
  background:var(--bg);
  color:var(--ink);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
}
img{ max-width:100%; display:block; }
a{ color:inherit; text-decoration:none; }
ul{ margin:0; padding:0; list-style:none; }
h1,h2,h3,h4{
  font-family:var(--font-display);
  font-weight:700;
  line-height:1.05;
  margin:0 0 .4em;
  letter-spacing:.01em;
  color:var(--steel-dark);
}
h1{ font-size:clamp(2.6rem, 5.4vw, 4.6rem); text-transform:uppercase; letter-spacing:.01em; }
h2{ font-size:clamp(1.9rem, 3.6vw, 2.9rem); text-transform:uppercase; }
h3{ font-size:clamp(1.25rem, 2vw, 1.6rem); text-transform:uppercase; }
p{ margin:0 0 1em; color:var(--ink-soft); }
.container{
  width:100%;
  max-width:var(--container);
  margin:0 auto;
  padding:0 24px;
}

/* focus visibility */
a:focus-visible,button:focus-visible,input:focus-visible,textarea:focus-visible{
  outline:2px solid var(--copper);
  outline-offset:2px;
}
@media (prefers-reduced-motion: reduce){
  *{ animation-duration:.001ms !important; animation-iteration-count:1 !important; transition-duration:.001ms !important; scroll-behavior:auto !important; }
}

/* ---------- eyebrow / mono labels ---------- */
.eyebrow{
  font-family:var(--font-mono);
  font-size:.72rem;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--copper);
  display:inline-flex;
  align-items:center;
  gap:10px;
  margin-bottom:14px;
}
.eyebrow::before{
  content:"";
  width:22px;
  height:1px;
  background:var(--copper);
  display:inline-block;
}

/* ---------- system-line divider (signature element) ---------- */
.system-line{
  position:relative;
  height:2px;
  background:repeating-linear-gradient(90deg, var(--line) 0 10px, transparent 10px 16px);
  margin:0;
}
.system-line.dark{ background-image:repeating-linear-gradient(90deg, var(--line-dark) 0 10px, transparent 10px 16px); }
.system-line .node{
  position:absolute; top:50%; width:8px; height:8px; border-radius:50%;
  background:var(--copper); transform:translate(-50%,-50%);
  box-shadow:0 0 0 3px var(--bg);
}

/* ---------- header ---------- */
.site-header{
  position:sticky; top:0; z-index:100;
  background:var(--steel-deeper);
  border-bottom:1px solid var(--line-dark);
}
.header-bar{
  display:flex; align-items:center; justify-content:space-between;
  padding:14px 24px;
  max-width:var(--container); margin:0 auto;
}
.brand{
  display:flex; align-items:center; gap:10px;
  font-family:var(--font-display);
  color:#fff; font-size:1.4rem; letter-spacing:.02em; text-transform:uppercase;
}
.brand .mark{
  width:34px; height:34px; flex:none;
}
.brand small{
  display:block; font-family:var(--font-mono); font-size:.6rem; letter-spacing:.16em;
  color:var(--copper-light); text-transform:uppercase; margin-top:2px;
}
.nav-desktop{ display:flex; align-items:center; gap:30px; }
.nav-desktop a{
  font-family:var(--font-mono); font-size:.78rem; letter-spacing:.06em;
  text-transform:uppercase; color:#CBD4D8; position:relative; padding:6px 0;
}
.nav-desktop a:hover, .nav-desktop a.active{ color:#fff; }
.nav-desktop a.active::after{
  content:""; position:absolute; left:0; right:0; bottom:0; height:2px; background:var(--copper);
}
.nav-desktop .has-dropdown{ position:relative; }
.dropdown{
  position:absolute; top:100%; left:-16px; margin-top:14px;
  background:var(--panel); border:1px solid var(--line);
  min-width:280px; padding:8px; border-radius:var(--radius);
  box-shadow:0 18px 40px rgba(0,0,0,.25);
  opacity:0; visibility:hidden; transform:translateY(6px);
  transition:opacity .16s ease, transform .16s ease, visibility .16s;
}
.has-dropdown:hover .dropdown, .has-dropdown:focus-within .dropdown{
  opacity:1; visibility:visible; transform:translateY(0);
}
.dropdown a{
  display:block; color:var(--ink); font-family:var(--font-body);
  text-transform:none; letter-spacing:0; font-size:.9rem; padding:10px 12px; border-radius:2px;
}
.dropdown a:hover{ background:var(--bg-alt); color:var(--steel-dark); }
.header-cta{ display:flex; align-items:center; gap:18px; }
.header-phone{
  font-family:var(--font-mono); color:#fff; font-size:.85rem; display:flex; align-items:center; gap:8px;
}
.header-phone strong{ color:var(--copper-light); }
.btn{
  display:inline-flex; align-items:center; justify-content:center; gap:8px;
  font-family:var(--font-mono); font-size:.76rem; letter-spacing:.1em; text-transform:uppercase;
  padding:13px 22px; border-radius:2px; border:1px solid transparent; cursor:pointer;
  transition:transform .15s ease, background .2s ease, border-color .2s ease, color .2s ease;
  white-space:nowrap;
}
.btn-primary{ background:var(--copper); color:#12181D; }
.btn-primary:hover{ background:var(--copper-light); transform:translateY(-2px); }
.btn-ghost{ background:transparent; color:#fff; border-color:rgba(255,255,255,.35); }
.btn-ghost:hover{ border-color:#fff; }
.btn-dark{ background:var(--steel-dark); color:#fff; }
.btn-dark:hover{ background:var(--steel-deeper); transform:translateY(-2px); }
.btn-block{ width:100%; }

.menu-toggle{
  display:none; background:none; border:1px solid rgba(255,255,255,.3); color:#fff;
  width:42px; height:42px; border-radius:2px; align-items:center; justify-content:center;
  cursor:pointer;
}
.menu-toggle svg{ width:20px; height:20px; }

.mobile-nav{
  display:none; flex-direction:column; background:var(--steel-deeper);
  border-top:1px solid var(--line-dark);
}
.mobile-nav.open{ display:flex; }
.mobile-nav a{
  padding:16px 24px; font-family:var(--font-mono); font-size:.85rem; letter-spacing:.05em;
  text-transform:uppercase; color:#DCE3E6; border-bottom:1px solid var(--line-dark);
}
.mobile-nav .sub a{ padding-left:40px; text-transform:none; font-family:var(--font-body); font-size:.92rem; color:#B9C3C7; }
.mobile-nav .mobile-cta{ padding:20px 24px; }

/* ---------- hero ---------- */
.hero{
  position:relative;
  background:var(--steel-deeper);
  color:#fff;
  overflow:hidden;
  padding:76px 0 90px;
}
.hero::before{
  content:"";
  position:absolute; inset:0;
  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:44px 44px;
  mask-image:linear-gradient(180deg, rgba(0,0,0,.9), transparent 85%);
  pointer-events:none;
}
.hero-grid{
  position:relative; z-index:1;
  display:grid; grid-template-columns:1.15fr .85fr; gap:50px; align-items:center;
}
.hero h1{ color:#fff; margin-bottom:20px; }
.hero-lede{ color:#B9C6CC; font-size:1.1rem; max-width:52ch; margin-bottom:32px; }
.hero-ctas{ display:flex; gap:14px; flex-wrap:wrap; margin-bottom:44px; }
.hero-stats{
  display:flex; gap:0; border-top:1px solid var(--line-dark);
}
.hero-stats div{ flex:1; padding:20px 20px 0 0; }
.hero-stats .num{ font-family:var(--font-mono); font-size:1.7rem; color:var(--copper-light); display:block; }
.hero-stats .lbl{ font-family:var(--font-mono); font-size:.68rem; letter-spacing:.08em; text-transform:uppercase; color:#8FA0A7; }

.hero-diagram{ position:relative; }
.hero-diagram svg{ width:100%; height:auto; }

/* ---------- page hero (interior pages) ---------- */
.page-hero{
  background:var(--steel-deeper); color:#fff; padding:56px 0 46px; position:relative; overflow:hidden;
}
.page-hero::before{
  content:""; position:absolute; inset:0;
  background-image:linear-gradient(rgba(255,255,255,.045) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.045) 1px, transparent 1px);
  background-size:40px 40px;
  mask-image:radial-gradient(circle at 20% 30%, black, transparent 70%);
}
.page-hero .container{ position:relative; z-index:1; }
.breadcrumb{
  font-family:var(--font-mono); font-size:.72rem; letter-spacing:.08em; text-transform:uppercase;
  color:#8FA0A7; margin-bottom:16px;
}
.breadcrumb a:hover{ color:var(--copper-light); }
.page-hero h1{ color:#fff; max-width:18ch; margin-bottom:14px; }
.page-hero .lede{ color:#B9C6CC; max-width:60ch; font-size:1.05rem; margin-bottom:0; }

/* ---------- sections ---------- */
section{ padding:76px 0; }
.section-tight{ padding:52px 0; }
.section-alt{ background:var(--bg-alt); }
.section-dark{ background:var(--steel-deeper); color:#fff; }
.section-dark h2{ color:#fff; }
.section-dark p{ color:#B9C6CC; }
.section-head{ max-width:640px; margin-bottom:46px; }
.section-head.center{ margin-left:auto; margin-right:auto; text-align:center; }

/* ---------- grids / cards ---------- */
.grid{ display:grid; gap:26px; }
.grid-3{ grid-template-columns:repeat(3,1fr); }
.grid-4{ grid-template-columns:repeat(4,1fr); }
.grid-2{ grid-template-columns:repeat(2,1fr); }

.service-card{
  background:var(--panel); border:1px solid var(--line); border-radius:var(--radius);
  padding:30px 26px; transition:transform .18s ease, box-shadow .18s ease, border-color .18s;
  display:flex; flex-direction:column; height:100%;
}
.service-card:hover{ transform:translateY(-5px); box-shadow:0 18px 34px rgba(14,21,25,.1); border-color:var(--copper); }
.service-card .icon{ width:44px; height:44px; margin-bottom:18px; color:var(--copper); }
.service-card h3{ margin-bottom:10px; font-size:1.2rem; }
.service-card p{ font-size:.94rem; margin-bottom:20px; }
.service-card .card-link{
  margin-top:auto; font-family:var(--font-mono); font-size:.74rem; letter-spacing:.08em; text-transform:uppercase;
  color:var(--steel); display:inline-flex; align-items:center; gap:8px;
}
.service-card:hover .card-link{ color:var(--copper); }

.feature-row{ display:flex; gap:16px; align-items:flex-start; padding:22px 0; border-bottom:1px solid var(--line); }
.feature-row:last-child{ border-bottom:none; }
.feature-row .num{ font-family:var(--font-mono); color:var(--copper); font-size:.85rem; flex:none; padding-top:3px; }
.feature-row h4{ font-family:var(--font-body); font-weight:700; font-size:1.02rem; color:var(--steel-dark); margin-bottom:4px; }
.feature-row p{ margin:0; font-size:.94rem; }

.check-list li{ display:flex; gap:12px; align-items:flex-start; padding:9px 0; font-size:.96rem; color:var(--ink-soft); }
.check-list svg{ flex:none; width:18px; height:18px; color:var(--copper); margin-top:2px; }

/* stat strip */
.stat-strip{ background:var(--steel); color:#fff; padding:44px 0; }
.stat-strip .grid-4{ text-align:center; }
.stat-strip .num{ font-family:var(--font-mono); font-size:2.4rem; color:var(--copper-light); display:block; }
.stat-strip .lbl{ font-family:var(--font-mono); font-size:.7rem; letter-spacing:.08em; text-transform:uppercase; color:#C7D3D7; margin-top:6px; }

/* process */
.process-strip{ display:grid; grid-template-columns:repeat(4,1fr); gap:0; }
.process-step{ padding:0 24px 0 0; position:relative; }
.process-step .step-num{ font-family:var(--font-mono); font-size:.75rem; color:var(--copper); letter-spacing:.1em; }
.process-step h4{ margin:10px 0 8px; font-size:1.05rem; color:var(--steel-dark); font-family:var(--font-body); font-weight:700; }
.process-step p{ font-size:.92rem; }

/* service areas */
.area-tags{ display:flex; flex-wrap:wrap; gap:10px; }
.area-tags span{
  font-family:var(--font-mono); font-size:.75rem; letter-spacing:.04em; text-transform:uppercase;
  border:1px solid var(--line); padding:8px 14px; border-radius:20px; color:var(--ink-soft); background:var(--panel);
}

/* testimonial */
.quote-card{
  background:var(--panel); border-left:3px solid var(--copper); padding:28px 30px; border-radius:0 var(--radius) var(--radius) 0;
}
.quote-card p{ font-size:1.05rem; color:var(--steel-dark); font-style:italic; margin-bottom:14px; }
.quote-card .who{ font-family:var(--font-mono); font-size:.74rem; letter-spacing:.06em; text-transform:uppercase; color:var(--ink-soft); }

/* CTA band */
.cta-band{
  background:var(--copper); color:var(--steel-deeper); padding:56px 0; position:relative; overflow:hidden;
}
.cta-band .container{ display:flex; align-items:center; justify-content:space-between; gap:30px; flex-wrap:wrap; }
.cta-band h2{ color:var(--steel-deeper); margin-bottom:8px; }
.cta-band p{ color:#3B2A1A; margin:0; max-width:46ch; }
.cta-band .btn-dark{ flex:none; }

/* ---------- contact page ---------- */
.contact-grid{ display:grid; grid-template-columns:1fr 1fr; gap:60px; align-items:start; }
.contact-info-card{
  background:var(--steel-deeper); color:#fff; border-radius:var(--radius); padding:38px 34px;
}
.contact-info-card h3{ color:#fff; }
.info-row{ display:flex; gap:16px; padding:18px 0; border-bottom:1px solid var(--line-dark); align-items:flex-start; }
.info-row:last-child{ border-bottom:none; }
.info-row svg{ flex:none; width:22px; height:22px; color:var(--copper-light); margin-top:2px; }
.info-row .lbl{ font-family:var(--font-mono); font-size:.68rem; letter-spacing:.1em; text-transform:uppercase; color:#8FA0A7; margin-bottom:4px; }
.info-row a, .info-row span.value{ font-size:1rem; color:#fff; }

.form-card{ background:var(--panel); border:1px solid var(--line); border-radius:var(--radius); padding:38px 34px; }
.field{ margin-bottom:20px; }
.field label{ display:block; font-family:var(--font-mono); font-size:.72rem; letter-spacing:.08em; text-transform:uppercase; color:var(--ink-soft); margin-bottom:8px; }
.field input, .field textarea, .field select{
  width:100%; border:1px solid var(--line); border-radius:2px; padding:13px 14px; font-family:var(--font-body);
  font-size:.96rem; background:var(--bg); color:var(--ink);
}
.field textarea{ resize:vertical; min-height:130px; }
.field input:focus, .field textarea:focus, .field select:focus{ outline:2px solid var(--copper); border-color:var(--copper); }
.form-note{ font-size:.82rem; color:var(--ink-soft); margin-top:14px; }
.form-success{
  display:none; background:#EDF3EB; border:1px solid var(--ok); color:#2F4A2F; padding:16px 18px;
  border-radius:2px; font-size:.92rem; margin-bottom:20px;
}
.form-success.show{ display:block; }

/* ---------- footer ---------- */
.site-footer{ background:var(--steel-deeper); color:#B9C6CC; padding-top:60px; }
.footer-grid{ display:grid; grid-template-columns:1.4fr 1fr 1fr 1fr; gap:40px; padding-bottom:46px; }
.footer-brand .brand{ margin-bottom:14px; }
.footer-brand p{ color:#8FA0A7; font-size:.9rem; max-width:34ch; }
.footer-col h4{ color:#fff; font-family:var(--font-mono); font-size:.72rem; letter-spacing:.1em; text-transform:uppercase; margin-bottom:16px; }
.footer-col ul li{ padding:6px 0; }
.footer-col a{ color:#B9C6CC; font-size:.9rem; }
.footer-col a:hover{ color:var(--copper-light); }
.footer-bottom{ border-top:1px solid var(--line-dark); padding:22px 0; font-family:var(--font-mono); font-size:.72rem; color:#7C8C93; display:flex; justify-content:space-between; flex-wrap:wrap; gap:10px; }

/* ---------- utility ---------- */
.mt-0{ margin-top:0; }
.text-center{ text-align:center; }

/* ==========================================================================
   RESPONSIVE
   ========================================================================== */
@media (max-width: 1024px){
  .nav-desktop{ display:none; }
  .header-phone{ display:none; }
  .menu-toggle{ display:inline-flex; }
  .hero-grid{ grid-template-columns:1fr; }
  .hero-diagram{ order:-1; max-width:420px; margin:0 auto; }
  .grid-4{ grid-template-columns:repeat(2,1fr); }
  .grid-3{ grid-template-columns:repeat(2,1fr); }
  .process-strip{ grid-template-columns:repeat(2,1fr); row-gap:34px; }
  .contact-grid{ grid-template-columns:1fr; }
  .footer-grid{ grid-template-columns:1fr 1fr; row-gap:34px; }
}
@media (max-width: 640px){
  section{ padding:54px 0; }
  .grid-4{ grid-template-columns:1fr; }
  .grid-3{ grid-template-columns:1fr; }
  .grid-2{ grid-template-columns:1fr; }
  .hero{ padding:50px 0 60px; }
  .hero-stats{ flex-wrap:wrap; }
  .hero-stats div{ flex:0 0 50%; padding-bottom:16px; }
  .process-strip{ grid-template-columns:1fr; }
  .footer-grid{ grid-template-columns:1fr; }
  .cta-band .container{ flex-direction:column; align-items:flex-start; text-align:left; }
  .cta-band .btn-dark{ width:100%; justify-content:center; }
  .header-bar{ padding:12px 18px; }
  .brand{ font-size:1.15rem; }
}