/* ============================================================
   Duct Cleaning USA — Global Stylesheet
   ============================================================ */

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --blue:        #0052cc;
  --blue-dark:   #003d99;
  --blue-light:  #e8f0fe;
  --red:         #cc0000;
  --red-dark:    #990000;
  --accent:      #00b4d8;
  --dark:        #0d1b2a;
  --dark2:       #1a2e45;
  --text:        #2d3748;
  --muted:       #64748b;
  --border:      #e2e8f0;
  --white:       #ffffff;
  --off-white:   #f8fafc;
  --section-alt: #f1f5f9;
  --radius:      10px;
  --shadow:      0 4px 24px rgba(0,82,204,.10);
  --shadow-lg:   0 12px 40px rgba(0,82,204,.16);
  --transition:  .22s ease;
  --max-w:       1200px;
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', system-ui, sans-serif;
  color: var(--text);
  background: var(--white);
  line-height: 1.65;
  font-size: 16px;
}

/* ---- UTILITIES ---- */
.container { max-width: var(--max-w); margin: 0 auto; padding: 0 24px; }

.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 13px 28px; border-radius: 8px; font-weight: 600;
  font-size: .95rem; text-decoration: none; cursor: pointer;
  border: 2px solid transparent; transition: all var(--transition);
  white-space: nowrap;
}
.btn-primary { background: var(--red); color: var(--white); }
.btn-primary:hover { background: var(--red-dark); transform: translateY(-1px); box-shadow: var(--shadow); }
.btn-outline { background: transparent; color: var(--white); border-color: rgba(255,255,255,.6); }
.btn-outline:hover { background: rgba(255,255,255,.12); border-color: var(--white); }
.btn-outline-dark { background: transparent; color: var(--blue); border-color: var(--blue); }
.btn-outline-dark:hover { background: var(--blue); color: var(--white); }
.btn-white { background: var(--white); color: var(--red); }
.btn-white:hover { background: var(--blue-light); }
.btn-outline-white { background: transparent; color: var(--white); border-color: rgba(255,255,255,.7); }
.btn-outline-white:hover { background: rgba(255,255,255,.15); }
.btn-sm { padding: 9px 20px; font-size: .88rem; }

.section { padding: 88px 0; }
.section-alt { background: var(--section-alt); }
.section-dark { background: var(--dark); color: var(--white); }

.section-header { text-align: center; max-width: 640px; margin: 0 auto 56px; }
.section-header h2 { font-size: 2.1rem; font-weight: 800; color: var(--dark); margin: 10px 0 16px; line-height: 1.25; }
.section-header p { color: var(--muted); font-size: 1.05rem; }
.section-header.light h2 { color: var(--white); }
.section-header.light p { color: rgba(255,255,255,.72); }
.section-tag {
  display: inline-block; background: #fff0f0; color: var(--red);
  font-size: .8rem; font-weight: 700; letter-spacing: .08em;
  text-transform: uppercase; padding: 5px 14px; border-radius: 20px;
}
.section-tag.light { background: rgba(255,255,255,.15); color: #7dd3fc; }

.link-arrow { color: var(--blue); font-weight: 600; text-decoration: none; font-size: .95rem; }
.link-arrow:hover { text-decoration: underline; }

/* ============================================================
   NAVIGATION
   ============================================================ */
.nav-wrap {
  position: sticky; top: 0; z-index: 100;
  background: var(--white); border-bottom: 1px solid var(--border);
  box-shadow: 0 2px 12px rgba(0,0,0,.06);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 68px; }

.logo {
  font-size: 1.3rem; font-weight: 900; text-decoration: none;
  color: var(--dark); display: flex; align-items: center; gap: 6px;
  letter-spacing: -.01em;
}
.logo-light { color: var(--white); }
.logo-icon { font-size: 1.3rem; }
.logo-accent { color: var(--blue); }
.logo-usa {
  background: var(--red); color: var(--white);
  font-size: .75rem; font-weight: 800; padding: 2px 7px;
  border-radius: 4px; letter-spacing: .05em; margin-left: 2px;
}

.nav-links {
  display: flex; align-items: center; gap: 6px;
  list-style: none;
}
.nav-links a {
  text-decoration: none; color: var(--text); font-weight: 500;
  padding: 8px 14px; border-radius: 6px; transition: all var(--transition);
  font-size: .95rem;
}
.nav-links a:hover, .nav-links a.active { color: var(--blue); background: var(--blue-light); }
.nav-links .btn { margin-left: 8px; }

.nav-toggle { display: none; background: none; border: none; font-size: 1.5rem; cursor: pointer; color: var(--dark); }

/* ============================================================
   HERO
   ============================================================ */
.hero {
  position: relative; overflow: hidden;
  background: linear-gradient(135deg, var(--dark) 0%, var(--dark2) 60%, #0a3060 100%);
  color: var(--white); padding: 100px 0 80px;
  min-height: 82vh; display: flex; align-items: center;
}
.hero-bg {
  position: absolute; inset: 0;
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%230052cc' fill-opacity='0.06'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}
/* USA flag stripe accent */
.hero::after {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 4px;
  background: linear-gradient(90deg, var(--red) 0%, var(--red) 33%, var(--white) 33%, var(--white) 66%, var(--blue) 66%);
}
.hero-content { position: relative; max-width: 780px; }
.hero-badge {
  display: inline-flex; align-items: center; gap: 4px;
  background: rgba(204,0,0,.18); border: 1px solid rgba(204,0,0,.35);
  color: #fca5a5; font-size: .82rem; font-weight: 600;
  padding: 6px 16px; border-radius: 20px; margin-bottom: 24px;
  letter-spacing: .03em;
}
.hero h1 { font-size: clamp(2.2rem, 5vw, 3.4rem); font-weight: 800; line-height: 1.18; margin-bottom: 20px; }
.hero-sub { font-size: 1.15rem; color: rgba(255,255,255,.78); max-width: 580px; margin-bottom: 36px; line-height: 1.7; }
.hero-ctas { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 64px; }

.hero-stats {
  display: flex; gap: 40px; flex-wrap: wrap;
  border-top: 1px solid rgba(255,255,255,.12); padding-top: 36px;
}
.stat { display: flex; flex-direction: column; }
.stat-num { font-size: 2rem; font-weight: 800; color: var(--white); line-height: 1; }
.stat-label { font-size: .82rem; color: rgba(255,255,255,.55); margin-top: 4px; font-weight: 500; }

/* ============================================================
   TRUST BAR
   ============================================================ */
.trust-bar { background: var(--white); border-bottom: 1px solid var(--border); padding: 20px 0; }
.trust-inner { display: flex; align-items: center; gap: 32px; flex-wrap: wrap; }
.trust-label { font-size: .8rem; font-weight: 700; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); white-space: nowrap; }
.trust-logos { display: flex; gap: 24px; flex-wrap: wrap; }
.trust-logo {
  font-size: .85rem; font-weight: 600; color: var(--dark);
  padding: 6px 16px; background: var(--off-white); border: 1px solid var(--border);
  border-radius: 6px; white-space: nowrap;
}

/* ============================================================
   FEATURES GRID
   ============================================================ */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}
.feature-card {
  background: var(--white); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 32px 28px;
  transition: all var(--transition);
}
.feature-card:hover { box-shadow: var(--shadow); transform: translateY(-3px); border-color: var(--blue-light); }
.feature-icon { font-size: 2rem; margin-bottom: 16px; display: block; }
.feature-card h3 { font-size: 1.1rem; font-weight: 700; margin-bottom: 10px; color: var(--dark); }
.feature-card p { color: var(--muted); font-size: .95rem; }

/* ============================================================
   SERVICES GRID
   ============================================================ */
.services-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 24px; }
.service-card { background: var(--white); border-radius: var(--radius); overflow: hidden; border: 1px solid var(--border); transition: all var(--transition); }
.service-card:hover { box-shadow: var(--shadow-lg); transform: translateY(-4px); }
.service-img { height: 220px; background-size: cover; background-position: center; position: relative; display: flex; align-items: center; justify-content: center; overflow: hidden; }
.service-img.kitchen  { background: linear-gradient(135deg, #1a2e45, #0052cc); }
.service-img.hvac     { background: linear-gradient(135deg, #0a3060, #00b4d8); }
.service-img.industrial { background: linear-gradient(135deg, #1a2e45, #1e40af); }
.service-img.residential { background: linear-gradient(135deg, #0d3b5e, #0ea5e9); }
.service-body { padding: 24px; }
.service-body h3 { font-size: 1.05rem; font-weight: 700; color: var(--dark); margin-bottom: 8px; }
.service-body p { color: var(--muted); font-size: .9rem; margin-bottom: 14px; }
.section-cta { text-align: center; margin-top: 48px; }

/* ============================================================
   PROCESS
   ============================================================ */
.process-steps { display: flex; align-items: flex-start; justify-content: center; gap: 0; flex-wrap: wrap; }
.process-step { flex: 1; min-width: 180px; max-width: 220px; text-align: center; padding: 24px 16px; }
.step-num { font-size: 3rem; font-weight: 900; color: #fff0f0; line-height: 1; margin-bottom: 12px; display: block; -webkit-text-stroke: 2px var(--red); }
.process-step h3 { font-size: 1rem; font-weight: 700; color: var(--dark); margin-bottom: 8px; }
.process-step p { color: var(--muted); font-size: .88rem; }
.process-arrow { font-size: 2rem; color: var(--red); align-self: center; padding: 0 8px; opacity: .4; margin-top: -24px; }

/* ============================================================
   TESTIMONIALS
   ============================================================ */
.testimonials-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 24px; }
.testimonial-card { background: rgba(255,255,255,.07); border: 1px solid rgba(255,255,255,.12); border-radius: var(--radius); padding: 32px 28px; }
.stars { color: #fbbf24; font-size: 1.1rem; margin-bottom: 14px; }
.testimonial-card p { color: rgba(255,255,255,.8); font-size: .95rem; line-height: 1.7; margin-bottom: 20px; font-style: italic; }
.testimonial-author { display: flex; align-items: center; gap: 12px; }
.author-avatar { width: 44px; height: 44px; border-radius: 50%; background: var(--red); color: var(--white); display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: .9rem; flex-shrink: 0; }
.testimonial-author strong { display: block; color: var(--white); font-size: .9rem; }
.testimonial-author span { color: rgba(255,255,255,.5); font-size: .8rem; }

/* ============================================================
   CTA BANNER
   ============================================================ */
.cta-banner { background: linear-gradient(135deg, var(--red) 0%, var(--red-dark) 100%); padding: 72px 0; }
.cta-inner { display: flex; align-items: center; justify-content: space-between; gap: 32px; flex-wrap: wrap; }
.cta-banner h2 { font-size: 2rem; font-weight: 800; color: var(--white); margin-bottom: 8px; }
.cta-banner p { color: rgba(255,255,255,.78); font-size: 1.05rem; }
.cta-actions { display: flex; gap: 14px; flex-wrap: wrap; }

/* ============================================================
   SERVICES PAGE
   ============================================================ */
.page-hero { background: linear-gradient(135deg, var(--dark) 0%, var(--dark2) 100%); color: var(--white); padding: 80px 0 60px; text-align: center; }
.page-hero h1 { font-size: clamp(1.8rem, 4vw, 2.8rem); font-weight: 800; margin-bottom: 14px; }
.page-hero p { color: rgba(255,255,255,.72); font-size: 1.05rem; max-width: 560px; margin: 0 auto; }
.breadcrumb { display: flex; align-items: center; gap: 8px; justify-content: center; margin-bottom: 20px; }
.breadcrumb a { color: #7dd3fc; text-decoration: none; font-size: .88rem; }
.breadcrumb span { color: rgba(255,255,255,.4); font-size: .88rem; }

.services-full { display: flex; flex-direction: column; gap: 72px; }
.service-row { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; }
.service-row.reverse { direction: rtl; }
.service-row.reverse > * { direction: ltr; }
.service-visual { border-radius: 14px; overflow: hidden; height: 340px; display: flex; align-items: center; justify-content: center; font-size: 6rem; }
.service-visual.bg-kitchen  { background: linear-gradient(135deg, #1a2e45, #0052cc); }
.service-visual.bg-hvac     { background: linear-gradient(135deg, #0a3060, #00b4d8); }
.service-visual.bg-industrial { background: linear-gradient(135deg, #1a2e45, #1e40af); }
.service-visual.bg-resi     { background: linear-gradient(135deg, #0d3b5e, #0ea5e9); }
.service-visual.bg-fire     { background: linear-gradient(135deg, #7f1d1d, #dc2626); }
.service-visual.bg-air      { background: linear-gradient(135deg, #064e3b, #059669); }
.service-text h2 { font-size: 1.7rem; font-weight: 800; color: var(--dark); margin-bottom: 14px; }
.service-text p { color: var(--muted); margin-bottom: 14px; }
.service-list { list-style: none; display: flex; flex-direction: column; gap: 8px; margin: 16px 0 24px; }
.service-list li { display: flex; align-items: flex-start; gap: 10px; font-size: .95rem; color: var(--text); }
.service-list li::before { content: '✓'; color: var(--red); font-weight: 700; flex-shrink: 0; margin-top: 1px; }

/* Pricing */
.pricing-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 24px; margin-top: 48px; }
.pricing-card { border: 2px solid var(--border); border-radius: var(--radius); padding: 32px 24px; text-align: center; transition: all var(--transition); }
.pricing-card:hover { border-color: var(--red); box-shadow: var(--shadow); }
.pricing-card.popular { border-color: var(--red); position: relative; }
.popular-badge { position: absolute; top: -13px; left: 50%; transform: translateX(-50%); background: var(--red); color: var(--white); font-size: .75rem; font-weight: 700; padding: 4px 14px; border-radius: 20px; }
.pricing-tier { font-size: .8rem; font-weight: 700; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); margin-bottom: 8px; }
.pricing-card h3 { font-size: 1.2rem; font-weight: 800; color: var(--dark); margin-bottom: 16px; }
.price { font-size: 2.4rem; font-weight: 900; color: var(--red); margin-bottom: 4px; line-height: 1; }
.price sup { font-size: 1.2rem; vertical-align: top; margin-top: 6px; font-weight: 700; }
.price-note { font-size: .8rem; color: var(--muted); margin-bottom: 20px; }
.pricing-features { list-style: none; text-align: left; display: flex; flex-direction: column; gap: 8px; margin-bottom: 24px; }
.pricing-features li { font-size: .88rem; display: flex; gap: 8px; color: var(--text); }
.pricing-features li::before { content: '✓'; color: var(--red); font-weight: 700; flex-shrink: 0; }

/* ============================================================
   ABOUT PAGE
   ============================================================ */
.about-intro { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: center; }
.about-visual { border-radius: 14px; height: 420px; display: flex; align-items: center; justify-content: center; font-size: 7rem; background: linear-gradient(135deg, var(--dark), var(--dark2)); }
.about-text h2 { font-size: 2rem; font-weight: 800; color: var(--dark); margin-bottom: 16px; }
.about-text p { color: var(--muted); margin-bottom: 14px; line-height: 1.75; }
.values-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 24px; }
.value-card { background: var(--white); border: 1px solid var(--border); border-radius: var(--radius); padding: 28px 24px; }
.value-card .value-icon { font-size: 2rem; margin-bottom: 12px; display: block; }
.value-card h3 { font-size: 1rem; font-weight: 700; color: var(--dark); margin-bottom: 8px; }
.value-card p { color: var(--muted); font-size: .9rem; }
.team-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 24px; }
.team-card { text-align: center; }
.team-avatar { width: 100px; height: 100px; border-radius: 50%; margin: 0 auto 16px; display: flex; align-items: center; justify-content: center; font-size: 1.4rem; font-weight: 700; color: var(--white); }
.team-card h3 { font-size: 1rem; font-weight: 700; color: var(--dark); margin-bottom: 4px; }
.team-card span { font-size: .85rem; color: var(--muted); }
.accreditations-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 20px; }
.accred-card { border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; text-align: center; }
.accred-card .accred-icon { font-size: 2.2rem; margin-bottom: 10px; display: block; }
.accred-card h4 { font-size: .95rem; font-weight: 700; color: var(--dark); margin-bottom: 6px; }
.accred-card p { font-size: .82rem; color: var(--muted); }

/* ============================================================
   CONTACT PAGE
   ============================================================ */
.contact-layout { display: grid; grid-template-columns: 1fr 1.6fr; gap: 56px; align-items: start; }
.contact-info h2 { font-size: 1.7rem; font-weight: 800; color: var(--dark); margin-bottom: 14px; }
.contact-info p { color: var(--muted); margin-bottom: 28px; }
.contact-items { display: flex; flex-direction: column; gap: 20px; }
.contact-item { display: flex; gap: 16px; align-items: flex-start; }
.contact-item-icon { width: 44px; height: 44px; border-radius: 10px; background: #fff0f0; display: flex; align-items: center; justify-content: center; font-size: 1.2rem; flex-shrink: 0; }
.contact-item-text strong { display: block; font-weight: 700; color: var(--dark); font-size: .9rem; margin-bottom: 2px; }
.contact-item-text span, .contact-item-text a { color: var(--muted); font-size: .9rem; text-decoration: none; }
.contact-item-text a:hover { color: var(--red); }
.contact-hours { margin-top: 32px; background: var(--off-white); border-radius: var(--radius); padding: 24px; }
.contact-hours h3 { font-size: 1rem; font-weight: 700; color: var(--dark); margin-bottom: 12px; }
.hours-row { display: flex; justify-content: space-between; padding: 6px 0; border-bottom: 1px solid var(--border); font-size: .88rem; }
.hours-row:last-child { border-bottom: none; }
.hours-row span:first-child { color: var(--text); font-weight: 500; }
.hours-row span:last-child { color: var(--muted); }
.contact-form-wrap { background: var(--white); border: 1px solid var(--border); border-radius: 14px; padding: 40px; box-shadow: var(--shadow); }
.contact-form-wrap h3 { font-size: 1.4rem; font-weight: 800; color: var(--dark); margin-bottom: 6px; }
.contact-form-wrap .form-sub { color: var(--muted); margin-bottom: 28px; font-size: .95rem; }
.form-group { margin-bottom: 20px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
label { display: block; font-size: .88rem; font-weight: 600; color: var(--dark); margin-bottom: 6px; }
input, select, textarea { width: 100%; padding: 12px 14px; border: 1.5px solid var(--border); border-radius: 8px; font-size: .95rem; font-family: inherit; color: var(--text); background: var(--white); transition: border var(--transition); }
input:focus, select:focus, textarea:focus { outline: none; border-color: var(--red); box-shadow: 0 0 0 3px rgba(204,0,0,.08); }
textarea { resize: vertical; min-height: 120px; }
.form-submit .btn { width: 100%; justify-content: center; padding: 14px; }
.form-note { font-size: .8rem; color: var(--muted); margin-top: 12px; text-align: center; }
.emergency-card { background: linear-gradient(135deg, #7f1d1d, #dc2626); color: var(--white); border-radius: var(--radius); padding: 28px; margin-top: 24px; text-align: center; }
.emergency-card h3 { font-size: 1.1rem; font-weight: 700; margin-bottom: 6px; }
.emergency-card p { font-size: .88rem; opacity: .85; margin-bottom: 14px; }
.emergency-card a { color: var(--white); text-decoration: none; font-size: 1.3rem; font-weight: 800; }

/* ============================================================
   FAQ
   ============================================================ */
.faq-list { max-width: 760px; margin: 0 auto; display: flex; flex-direction: column; gap: 12px; }
.faq-item { border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; }
.faq-q { display: flex; align-items: center; justify-content: space-between; padding: 18px 22px; cursor: pointer; font-weight: 600; color: var(--dark); background: var(--white); user-select: none; gap: 16px; }
.faq-q:hover { background: var(--off-white); }
.faq-arrow { font-size: 1.2rem; color: var(--red); transition: transform var(--transition); flex-shrink: 0; }
.faq-item.open .faq-arrow { transform: rotate(180deg); }
.faq-a { padding: 0 22px; max-height: 0; overflow: hidden; transition: max-height .3s ease, padding .3s; }
.faq-item.open .faq-a { max-height: 300px; padding: 0 22px 18px; }
.faq-a p { color: var(--muted); font-size: .95rem; line-height: 1.7; }

/* ============================================================
   FOOTER
   ============================================================ */
.footer { background: var(--dark); color: var(--white); padding: 72px 0 0; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 48px; }
.footer-brand p { color: rgba(255,255,255,.55); font-size: .9rem; margin-top: 14px; line-height: 1.7; }
.footer-contact-line { margin-top: 8px; font-size: .9rem; }
.footer-contact-line a { color: rgba(255,255,255,.75); text-decoration: none; }
.footer-contact-line a:hover { color: var(--white); }
.footer-col h4 { font-size: .9rem; font-weight: 700; margin-bottom: 16px; color: var(--white); }
.footer-col ul { list-style: none; display: flex; flex-direction: column; gap: 8px; }
.footer-col ul li { font-size: .88rem; color: rgba(255,255,255,.5); }
.footer-col ul li a { color: rgba(255,255,255,.5); text-decoration: none; transition: color var(--transition); }
.footer-col ul li a:hover { color: var(--white); }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.08); padding: 20px 0; }
.footer-bottom p { font-size: .82rem; color: rgba(255,255,255,.35); }

/* ============================================================
   INTERACTIVE VENT SECTION
   ============================================================ */
.duct-interactive {
  background: linear-gradient(160deg, #050e1a 0%, #0d1b2a 50%, #0a1428 100%);
  padding: 96px 0;
  overflow: hidden;
  position: relative;
}
.duct-interactive::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 50% 60%, rgba(0,82,204,.12) 0%, transparent 70%);
  pointer-events: none;
}
.duct-interactive .section-header { margin-bottom: 64px; }

/* Three-column layout */
.vent-demo-layout {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 48px;
  flex-wrap: wrap;
}

/* Side info cards */
.demo-side { flex: 1; min-width: 180px; max-width: 220px; }
.demo-card {
  border-radius: 14px;
  padding: 28px 22px;
  border: 1px solid rgba(255,255,255,.08);
}
.dirty-card { background: rgba(120,40,40,.18); border-color: rgba(220,38,38,.2); }
.clean-card  { background: rgba(0,82,204,.15);  border-color: rgba(0,180,216,.2); }
.demo-card-icon { font-size: 2rem; margin-bottom: 12px; }
.demo-card h4 { font-size: 1rem; font-weight: 700; color: var(--white); margin-bottom: 12px; }
.demo-card ul { list-style: none; display: flex; flex-direction: column; gap: 7px; }
.demo-card ul li { font-size: .82rem; color: rgba(255,255,255,.6); padding-left: 14px; position: relative; }
.demo-card ul li::before { content: '•'; position: absolute; left: 0; }
.dirty-card ul li::before { color: #ef4444; }
.clean-card  ul li::before { color: #00b4d8; }

/* ---- VENT OUTER ---- */
.vent-outer {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

/* ---- 3D VENT WRAP ---- */
.vent-wrap {
  width: 320px;
  height: 300px;
  position: relative;
  cursor: pointer;
  transform-style: preserve-3d;
  transform: perspective(900px) rotateX(6deg) rotateY(-8deg);
  transition: transform .6s cubic-bezier(.23,1,.32,1), box-shadow .6s ease;
  border-radius: 10px;
  overflow: visible;
}
/* JS will drive hover tilt, but CSS fallback: */
.vent-outer:hover .vent-wrap {
  transform: perspective(900px) rotateX(2deg) rotateY(4deg);
}

/* Housing depth sides — create a 3D box illusion */
.housing-side {
  position: absolute;
  background: linear-gradient(to bottom, #1e3a5f, #0d2240);
  z-index: 1;
}
.h-top    { top: -18px; left: 8px; right: -8px; height: 18px;
            transform: skewX(-45deg); border-radius: 3px 3px 0 0;
            background: linear-gradient(90deg, #1e3a5f, #0a2040); }
.h-right  { top: -10px; right: -18px; bottom: 8px; width: 18px;
            transform: skewY(-45deg); border-radius: 0 3px 3px 0;
            background: linear-gradient(180deg, #0d2240, #051020); }
.h-bottom { bottom: -14px; left: 8px; right: -8px; height: 14px;
            transform: skewX(-45deg);
            background: linear-gradient(90deg, #051020, #0a1428); }
.h-left   { display: none; }

/* Interior behind slats */
.vent-interior {
  position: absolute;
  inset: 4px;
  border-radius: 6px;
  overflow: hidden;
  z-index: 2;
  transition: background .5s ease;
  background: #080e14;
}

/* Dust specks shown when closed */
.interior-dust {
  position: absolute; inset: 0;
  display: flex; flex-wrap: wrap;
  align-items: center; justify-content: center;
  gap: 18px; padding: 20px;
  opacity: 1;
  transition: opacity .6s ease .1s;
}
.interior-dust span {
  display: block;
  border-radius: 50%;
  background: rgba(160,120,80,.55);
  animation: dustFloat 4s ease-in-out infinite;
}
.interior-dust span:nth-child(1)  { width:18px; height:18px; animation-delay:0s; }
.interior-dust span:nth-child(2)  { width:10px; height:10px; animation-delay:.4s; }
.interior-dust span:nth-child(3)  { width:22px; height:22px; animation-delay:.8s; }
.interior-dust span:nth-child(4)  { width: 8px; height: 8px; animation-delay:1.2s; }
.interior-dust span:nth-child(5)  { width:14px; height:14px; animation-delay:1.6s; }
.interior-dust span:nth-child(6)  { width:20px; height:20px; animation-delay:.2s; }
.interior-dust span:nth-child(7)  { width: 6px; height: 6px; animation-delay:.6s; }
.interior-dust span:nth-child(8)  { width:16px; height:16px; animation-delay:1s;  }
.interior-dust span:nth-child(9)  { width:12px; height:12px; animation-delay:1.4s;}
.interior-dust span:nth-child(10) { width:24px; height:24px; animation-delay:1.8s;}

@keyframes dustFloat {
  0%,100% { transform: translateY(0) rotate(0deg);   opacity:.55; }
  50%      { transform: translateY(-6px) rotate(20deg); opacity:.35; }
}

/* Clean glow behind slats (visible when open) */
.interior-clean-glow {
  position: absolute; inset: 0;
  background: radial-gradient(ellipse at 50% 40%, rgba(0,180,216,.7) 0%, rgba(0,82,204,.4) 45%, transparent 75%);
  opacity: 0;
  transition: opacity .5s ease .15s;
}

/* ---- SLATS (LOUVERS) ---- */
.slats-container {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  justify-content: space-evenly;
  padding: 10px 6px;
  z-index: 10;
  perspective: 400px;
  transform-style: preserve-3d;
}

.slat {
  width: 100%;
  height: 24px;
  background: linear-gradient(180deg,
    #b0bec5 0%, #90a4ae 30%, #607d8b 70%, #455a64 100%);
  border-radius: 2px;
  transform-origin: center center;
  transform: rotateX(0deg);
  transition: transform .45s cubic-bezier(.4,0,.2,1);
  transition-delay: calc(var(--i) * 0.04s);
  position: relative;
  box-shadow: 0 2px 4px rgba(0,0,0,.5), inset 0 1px 0 rgba(255,255,255,.2);
}
/* Slat edge highlight */
.slat::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0; height: 3px;
  background: rgba(255,255,255,.25);
  border-radius: 2px 2px 0 0;
}
/* Open state — triggered by .vent-outer:hover or JS class */
.vent-outer:hover .slat,
.vent-open .slat {
  transform: rotateX(-72deg);
}

/* ---- FRONT FRAME RIM ---- */
.vent-frame-rim {
  position: absolute;
  inset: 0;
  border: 6px solid #607d8b;
  border-radius: 10px;
  z-index: 20;
  pointer-events: none;
  box-shadow:
    inset 0 0 0 2px rgba(255,255,255,.08),
    0 0 30px rgba(0,0,0,.6);
}
/* Corner bolts */
.vent-frame-rim::before,
.vent-frame-rim::after {
  content: '';
  position: absolute;
  width: 10px; height: 10px;
  background: radial-gradient(circle, #cfd8dc, #607d8b);
  border-radius: 50%;
  border: 1px solid rgba(0,0,0,.3);
}
.vent-frame-rim::before { top: 8px; left: 8px; box-shadow: 290px 0 0 #90a4ae; }
.vent-frame-rim::after  { bottom: 8px; left: 8px; box-shadow: 290px 0 0 #90a4ae; }

/* ---- AIRFLOW STREAMS ---- */
.airflow {
  position: absolute;
  inset: 0;
  z-index: 5;
  pointer-events: none;
  overflow: hidden;
  border-radius: 8px;
  opacity: 0;
  transition: opacity .3s ease .3s;
}
.vent-outer:hover .airflow,
.vent-open .airflow { opacity: 1; }

.airstream {
  position: absolute;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(to bottom, transparent, rgba(0,180,216,.7), transparent);
  animation: streamDown 1.4s ease-in-out infinite;
  opacity: 0;
}
.vent-outer:hover .airstream,
.vent-open .airstream { opacity: 1; }

.as1 { left:10%;  height:60px; animation-delay:0s;    animation-duration:1.2s; }
.as2 { left:25%;  height:80px; animation-delay:.2s;   animation-duration:1.5s; }
.as3 { left:42%;  height:55px; animation-delay:.4s;   animation-duration:1.1s; }
.as4 { left:58%;  height:70px; animation-delay:.1s;   animation-duration:1.3s; }
.as5 { left:74%;  height:65px; animation-delay:.3s;   animation-duration:1.6s; }
.as6 { left:88%;  height:50px; animation-delay:.5s;   animation-duration:1.0s; }

@keyframes streamDown {
  0%   { transform: translateY(-30px); opacity:0; }
  20%  { opacity:.8; }
  80%  { opacity:.5; }
  100% { transform: translateY(320px); opacity:0; }
}

/* Interior lighting on hover */
.vent-outer:hover .interior-dust,
.vent-open .interior-dust { opacity: 0; }
.vent-outer:hover .interior-clean-glow,
.vent-open .interior-clean-glow { opacity: 1; }
.vent-outer:hover .vent-interior,
.vent-open .vent-interior { background: #020d1a; }

/* ---- STATUS LABEL ---- */
.vent-status {
  font-size: .82rem;
  font-weight: 700;
  letter-spacing: .06em;
  text-align: center;
}
.status-closed { color: rgba(255,255,255,.4); display: block; }
.status-open   { color: #00b4d8; display: none; }
.vent-outer:hover .status-closed,
.vent-open .status-closed { display: none; }
.vent-outer:hover .status-open,
.vent-open .status-open   { display: block; }

/* ---- AIRFLOW METER ---- */
.airflow-meter {
  display: flex;
  align-items: center;
  gap: 10px;
  width: 320px;
}
.meter-label {
  font-size: .72rem;
  font-weight: 700;
  color: rgba(255,255,255,.4);
  text-transform: uppercase;
  letter-spacing: .08em;
  white-space: nowrap;
  width: 50px;
}
.meter-track {
  flex: 1;
  height: 8px;
  background: rgba(255,255,255,.08);
  border-radius: 4px;
  overflow: hidden;
}
.meter-bar {
  height: 100%;
  width: 12%;
  background: linear-gradient(90deg, #ef4444, #f97316);
  border-radius: 4px;
  transition: width .8s cubic-bezier(.4,0,.2,1), background .8s ease;
}
.vent-outer:hover .meter-bar,
.vent-open .meter-bar {
  width: 94%;
  background: linear-gradient(90deg, #0052cc, #00b4d8);
}
.meter-pct {
  font-size: .72rem;
  font-weight: 700;
  color: #ef4444;
  width: 34px;
  text-align: right;
  transition: color .4s ease;
}
.vent-outer:hover .meter-pct,
.vent-open .meter-pct { color: #00b4d8; }

/* ============================================================
   HERO 2-COLUMN LAYOUT
   ============================================================ */
.hero-inner {
  display: flex;
  align-items: center;
  gap: 64px;
  width: 100%;
}
.hero-content { flex: 1; min-width: 0; }
.hero-3d-wrap {
  flex-shrink: 0;
  width: 340px;
  height: 340px;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* ============================================================
   3D ROTATING DUCT
   ============================================================ */
.duct-scene {
  width: 280px;
  height: 280px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  perspective: 700px;
}

/* Rotating box */
.duct-box {
  width: 220px;
  height: 130px;
  position: relative;
  transform-style: preserve-3d;
  animation: rotateDuct 10s linear infinite;
}

@keyframes rotateDuct {
  0%   { transform: rotateX(-18deg) rotateY(0deg); }
  100% { transform: rotateX(-18deg) rotateY(360deg); }
}

/* Shared face styles */
.duct-face {
  position: absolute;
  background: linear-gradient(135deg, #b0bec5 0%, #78909c 40%, #546e7a 100%);
  border: 1px solid rgba(255,255,255,.15);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

/* Metallic sheen overlay on all faces */
.duct-face::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255,255,255,.18) 0%, transparent 60%);
  pointer-events: none;
}

/* Front face — W=220, H=130, translateZ(depth/2=90) */
.face-front {
  width: 220px; height: 130px;
  top: 0; left: 0;
  transform: translateZ(90px);
  background: linear-gradient(160deg, #90a4ae 0%, #607d8b 50%, #455a64 100%);
}

/* Back face */
.face-back {
  width: 220px; height: 130px;
  top: 0; left: 0;
  transform: translateZ(-90px) rotateY(180deg);
  background: linear-gradient(160deg, #546e7a 0%, #37474f 100%);
}

/* Top face — W=220, D=180, translateY(-H/2=-65) rotateX(90) */
.face-top {
  width: 220px; height: 180px;
  top: 0; left: 0;
  transform: translateY(-65px) rotateX(90deg);
  background: linear-gradient(180deg, #cfd8dc 0%, #90a4ae 50%, #607d8b 100%);
  display: flex;
  flex-direction: row;
  align-items: center;
  justify-content: space-evenly;
  padding: 0 20px;
  gap: 12px;
}

/* Bottom face */
.face-bottom {
  width: 220px; height: 180px;
  top: 0; left: 0;
  transform: translateY(65px) rotateX(-90deg);
  background: linear-gradient(0deg, #37474f 0%, #546e7a 100%);
}

/* Left face — W=180, H=130 */
.face-left {
  width: 180px; height: 130px;
  top: 0; left: 0;
  transform: translateX(-90px) rotateY(-90deg);
  background: linear-gradient(90deg, #37474f 0%, #546e7a 100%);
}

/* Right face */
.face-right {
  width: 180px; height: 130px;
  top: 0; left: 0;
  transform: translateX(130px) rotateY(90deg);
  background: linear-gradient(270deg, #37474f 0%, #607d8b 100%);
}

/* Circular duct opening on front/back */
.duct-opening {
  width: 90px;
  height: 90px;
  border-radius: 50%;
  background: radial-gradient(circle at 35% 35%, #1a2e45, #0d1b2a 60%, #000 100%);
  border: 4px solid #37474f;
  box-shadow: inset 0 0 20px rgba(0,0,0,.8), 0 0 12px rgba(0,180,216,.3);
  position: relative;
}
.duct-opening::after {
  content: '';
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  width: 60px; height: 60px;
  border-radius: 50%;
  border: 2px solid rgba(0,180,216,.25);
}

/* Ventilation slots on top */
.duct-slot {
  width: 48px;
  height: 8px;
  background: rgba(0,0,0,.5);
  border-radius: 4px;
  box-shadow: inset 0 2px 4px rgba(0,0,0,.6);
  flex-shrink: 0;
}

/* Floating air particles */
.particle {
  position: absolute;
  border-radius: 50%;
  background: rgba(0,180,216,.6);
  animation: floatUp 3s ease-in-out infinite;
  pointer-events: none;
}
.p1 { width:8px;  height:8px;  top:30%;  left:20%;  animation-delay:0s;    animation-duration:2.8s; }
.p2 { width:5px;  height:5px;  top:50%;  left:75%;  animation-delay:.6s;   animation-duration:3.2s; }
.p3 { width:10px; height:10px; top:60%;  left:40%;  animation-delay:1.1s;  animation-duration:2.5s; }
.p4 { width:4px;  height:4px;  top:25%;  left:60%;  animation-delay:1.7s;  animation-duration:3.5s; }
.p5 { width:6px;  height:6px;  top:70%;  left:55%;  animation-delay:.3s;   animation-duration:2.2s; }

@keyframes floatUp {
  0%   { transform: translateY(0) scale(1);   opacity: 0; }
  20%  { opacity: .8; }
  80%  { opacity: .4; }
  100% { transform: translateY(-80px) scale(.4); opacity: 0; }
}

/* Glow ring beneath the duct */
.duct-glow {
  position: absolute;
  bottom: 10px;
  left: 50%;
  transform: translateX(-50%);
  width: 200px;
  height: 20px;
  background: radial-gradient(ellipse, rgba(0,82,204,.45) 0%, transparent 70%);
  border-radius: 50%;
  animation: glowPulse 3s ease-in-out infinite;
  pointer-events: none;
}
@keyframes glowPulse {
  0%, 100% { opacity: .5; transform: translateX(-50%) scaleX(1); }
  50%       { opacity: 1;  transform: translateX(-50%) scaleX(1.15); }
}

/* Label below duct */
.duct-label {
  position: absolute;
  bottom: -8px;
  left: 50%;
  transform: translateX(-50%);
  font-size: .65rem;
  font-weight: 700;
  letter-spacing: .15em;
  color: rgba(255,255,255,.25);
  white-space: nowrap;
}

/* ============================================================
   SERVICE PAGE — INTERACTIVE 3D ELEMENTS
   ============================================================ */

/* === 1. KITCHEN — Grease Filter === */
.filter-wrap {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}
.filter-frame {
  position: relative;
  width: 200px;
  height: 200px;
  border: 6px solid #5a6a75;
  border-radius: 8px;
  background: #111;
  overflow: hidden;
  transform: rotateX(6deg) rotateY(-6deg);
  transform-style: preserve-3d;
  transition: transform .5s ease, box-shadow .5s ease;
  box-shadow: 4px 6px 20px rgba(0,0,0,.5);
}
.bg-kitchen:hover .filter-frame {
  transform: rotateX(0deg) rotateY(0deg);
  box-shadow: 0 0 24px rgba(180,220,255,.25);
}
.filter-bars {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  padding: 8px;
  gap: 3px;
}
.fb {
  flex: 1;
  border-radius: 2px;
  background: linear-gradient(90deg, #6a4015 0%, #b07030 40%, #d09050 50%, #b07030 60%, #6a4015 100%);
  box-shadow: inset 0 1px 2px rgba(255,200,80,.1), 0 1px 0 rgba(0,0,0,.5);
  transition: background .55s ease, box-shadow .55s ease;
  transition-delay: calc(var(--i) * 0.06s);
}
.bg-kitchen:hover .fb {
  background: linear-gradient(90deg, #8090a0 0%, #b8ccd8 40%, #ddeeff 50%, #b8ccd8 60%, #8090a0 100%);
  box-shadow: inset 0 1px 2px rgba(255,255,255,.25), 0 1px 0 rgba(0,0,0,.15);
}
.filter-crossbars {
  position: absolute;
  inset: 8px;
  display: flex;
}
.fcb {
  flex: 1;
  margin: 0 3px;
  background: rgba(90,55,15,.6);
  border-radius: 1px;
  transition: background .55s ease;
  transition-delay: calc(var(--j) * 0.06s);
}
.bg-kitchen:hover .fcb {
  background: rgba(140,175,205,.45);
}
.grease-overlay {
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 25% 75%, rgba(160,100,20,.55) 0%, transparent 55%),
              radial-gradient(ellipse at 70% 20%, rgba(180,120,30,.45) 0%, transparent 45%);
  pointer-events: none;
  transition: opacity .55s ease;
}
.bg-kitchen:hover .grease-overlay { opacity: 0; }
.clean-shine {
  position: absolute;
  inset: 0;
  background: linear-gradient(115deg, transparent 30%, rgba(255,255,255,.22) 50%, transparent 70%);
  transform: translateX(-150%) skewX(-20deg);
  pointer-events: none;
}
.bg-kitchen:hover .clean-shine {
  transform: translateX(250%) skewX(-20deg);
  transition: transform .65s ease .15s;
}
.filter-tag {
  font-size: .62rem;
  font-weight: 700;
  letter-spacing: .12em;
  color: #ef4444;
  transition: color .5s ease;
}
.bg-kitchen:hover .filter-tag { color: #22c55e; }

/* === 2. HVAC — Spinning Fan === */
.fan-wrap {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}
.fan-housing {
  position: relative;
  width: 200px;
  height: 200px;
  border-radius: 50%;
  background: radial-gradient(circle at 38% 32%, #2c3a44, #101820);
  border: 5px solid #1e2d3a;
  box-shadow: inset 0 0 32px rgba(0,0,0,.65), 0 8px 28px rgba(0,0,0,.45);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}
.dust-ring {
  position: absolute;
  inset: 10px;
  border-radius: 50%;
  border: 3px dashed rgba(140,110,70,.45);
  transition: opacity .5s ease;
}
.bg-hvac:hover .dust-ring { opacity: 0; }
.fan-hub {
  position: relative;
  width: 160px;
  height: 160px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.fan-blades {
  position: absolute;
  width: 100%;
  height: 100%;
  animation: fanSpin 4s linear infinite;
  transition: animation-duration .3s;
}
.bg-hvac:hover .fan-blades { animation-duration: .45s; }
@keyframes fanSpin { to { transform: rotate(360deg); } }
.fblade {
  position: absolute;
  width: 58px;
  height: 24px;
  top: 50%;
  left: 50%;
  transform-origin: 0 50%;
  border-radius: 50% 50% 50% 0;
  background: linear-gradient(135deg, #546070, #38485a);
  box-shadow: inset 0 2px 3px rgba(255,255,255,.1);
  transform: rotate(calc(var(--b) * 90deg)) translateY(-50%);
  transition: background .5s ease, filter .5s ease;
}
.bg-hvac:hover .fblade {
  background: linear-gradient(135deg, #3a90e0, #0052cc);
  filter: drop-shadow(0 0 5px rgba(0,160,255,.5));
}
.fan-center {
  position: absolute;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: radial-gradient(circle, #8090a0, #384858);
  border: 2px solid #1a2838;
  z-index: 2;
  box-shadow: 0 2px 6px rgba(0,0,0,.5);
}
.fan-tag {
  font-size: .62rem;
  font-weight: 700;
  letter-spacing: .12em;
  color: rgba(255,255,255,.4);
  transition: color .4s ease;
}
.bg-hvac:hover .fan-tag { color: #00b4d8; }
.airflow-rings {
  position: absolute;
  inset: 0;
  pointer-events: none;
}
.aring {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 2px solid transparent;
  animation: ringExpand 1.8s ease-out infinite;
  animation-delay: calc(var(--r) * 0.6s);
  animation-play-state: paused;
}
.bg-hvac:hover .aring { animation-play-state: running; }
@keyframes ringExpand {
  0%   { transform: scale(.4); border-color: rgba(0,180,216,.7); opacity: 1; }
  100% { transform: scale(1.25); border-color: rgba(0,180,216,0); opacity: 0; }
}

/* === 3. INDUSTRIAL — Duct pipe cross-section === */
.indust-wrap {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}
.indust-pipe {
  position: relative;
  width: 230px;
  height: 180px;
  border-radius: 10px;
  background: linear-gradient(180deg, #3a4a52, #1e2a30 50%, #3a4a52);
  border: 4px solid #283840;
  overflow: hidden;
  box-shadow: inset 0 4px 12px rgba(0,0,0,.55), 0 8px 24px rgba(0,0,0,.45);
  transition: box-shadow .5s ease;
}
.bg-industrial:hover .indust-pipe {
  box-shadow: inset 0 2px 8px rgba(0,0,0,.2), 0 8px 24px rgba(0,80,200,.25);
}
.pipe-ring {
  position: absolute;
  top: 0; bottom: 0;
  width: 16px;
  background: linear-gradient(90deg, #4a5c66, #2a3c48, #4a5c66);
  border: 2px solid #1e2c38;
  z-index: 2;
}
.pipe-ring-left  { left: 0; border-radius: 6px 0 0 6px; }
.pipe-ring-right { right: 0; border-radius: 0 6px 6px 0; }
.pipe-interior {
  position: absolute;
  top: 12px; bottom: 12px;
  left: 16px; right: 16px;
  border-radius: 6px;
  background: #0c1418;
  overflow: hidden;
}
.pipe-buildup {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(90,60,25,.85) 0%, transparent 35%),
    linear-gradient(0deg,   rgba(80,55,20,.85) 0%, transparent 35%),
    linear-gradient(90deg,  rgba(65,42,18,.7) 0%, transparent 25%),
    linear-gradient(270deg, rgba(65,42,18,.7) 0%, transparent 25%);
  transition: opacity .65s ease;
}
.bg-industrial:hover .pipe-buildup { opacity: 0; }
.pipe-particles { position: absolute; inset: 0; }
.pp {
  position: absolute;
  width: 5px; height: 5px;
  border-radius: 50%;
  background: rgba(160,125,75,.85);
  left: var(--px);
  top: var(--py);
  animation: dustFloat 2.4s ease-in-out infinite;
  animation-delay: var(--pd);
  transition: opacity .4s ease;
}
.bg-industrial:hover .pp { opacity: 0; animation-play-state: paused; }
@keyframes dustFloat {
  0%, 100% { transform: translate(0,0); }
  33% { transform: translate(4px,-5px); }
  66% { transform: translate(-3px,4px); }
}
.indust-tag {
  font-size: .62rem;
  font-weight: 700;
  letter-spacing: .12em;
  color: rgba(255,255,255,.38);
  transition: color .4s ease;
}
.bg-industrial:hover .indust-tag { color: #22c55e; }

/* === 4. RESIDENTIAL — Mini louver vent === */
.mini-vent-outer {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  cursor: pointer;
}
.mini-vent-wrap { perspective: 600px; }
.mini-vent-frame {
  position: relative;
  width: 200px;
  height: 190px;
  border: 7px solid #b0bcc8;
  border-radius: 10px;
  background: #e4eaee;
  overflow: hidden;
  box-shadow: 4px 6px 18px rgba(0,0,0,.3), inset 0 2px 4px rgba(255,255,255,.6);
}
.mini-interior {
  position: absolute;
  inset: 0;
  background: #0a1828;
  z-index: 0;
}
.mini-glow {
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 50% 60%, rgba(0,100,220,.35) 0%, transparent 70%);
  opacity: 0;
  transition: opacity .4s ease .25s;
}
.mini-vent-outer:hover .mini-glow { opacity: 1; }
.mini-slats {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  padding: 10px 12px;
  gap: 5px;
  perspective: 450px;
  transform-style: preserve-3d;
  z-index: 1;
}
.mslat {
  flex: 1;
  background: linear-gradient(180deg, #d0dae2, #b8c6d0);
  border-radius: 2px;
  transform-origin: center center;
  transform: rotateX(0deg);
  transition: transform .42s cubic-bezier(.4,0,.2,1);
  transition-delay: calc(var(--i) * 0.045s);
  box-shadow: 0 2px 4px rgba(0,0,0,.18), inset 0 1px 0 rgba(255,255,255,.5);
}
.mini-vent-outer:hover .mslat { transform: rotateX(-72deg); }
.mini-vent-label {
  font-size: .62rem;
  font-weight: 700;
  letter-spacing: .12em;
  color: rgba(255,255,255,.42);
  transition: color .35s ease;
}
.mini-vent-outer:hover .mini-vent-label { color: #00b4d8; }

/* === 5. FIRE DAMPER — Hinged blade === */
.damper-wrap {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}
.damper-duct {
  position: relative;
  width: 210px;
  height: 185px;
  background: linear-gradient(180deg, #1c0a04, #120804);
  border: 4px solid #3a1808;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: inset 0 4px 14px rgba(0,0,0,.65), 0 8px 24px rgba(0,0,0,.5);
  overflow: visible;
}
.damper-frame-top, .damper-frame-bottom {
  position: absolute;
  left: -4px; right: -4px;
  height: 20px;
  background: linear-gradient(90deg, #4a2010, #884025, #4a2010);
  border: 2px solid #3a1808;
}
.damper-frame-top    { top: -4px;    border-radius: 10px 10px 0 0; }
.damper-frame-bottom { bottom: -4px; border-radius: 0 0 10px 10px; }
.damper-blade-scene {
  perspective: 500px;
  width: 168px;
  height: 145px;
  display: flex;
  align-items: flex-start;
  justify-content: center;
}
.damper-blade {
  width: 152px;
  height: 130px;
  background: linear-gradient(135deg, #922010 0%, #c84025 35%, #aa3020 55%, #922010 100%);
  border: 3px solid #621808;
  border-radius: 4px;
  transform-origin: top center;
  transform: rotateX(0deg);
  transition: transform .65s cubic-bezier(.4,0,.2,1);
  box-shadow: inset 0 3px 5px rgba(255,120,60,.1), 0 6px 14px rgba(0,0,0,.55);
}
.damper-blade::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 12%; right: 12%;
  height: 4px;
  background: rgba(220,90,40,.5);
  transform: translateY(-50%);
  border-radius: 2px;
}
.damper-blade::after {
  content: '';
  position: absolute;
  top: 12px;
  left: 50%;
  transform: translateX(-50%);
  width: 18px; height: 18px;
  border-radius: 50%;
  background: radial-gradient(circle, #d05030, #801808);
  border: 2px solid #501010;
  box-shadow: 0 0 8px rgba(200,80,40,.4);
}
.bg-fire:hover .damper-blade { transform: rotateX(-85deg); }
.fire-sparks {
  position: absolute;
  inset: 0;
  pointer-events: none;
  overflow: hidden;
  border-radius: 8px;
}
.fspark {
  position: absolute;
  width: 5px; height: 5px;
  border-radius: 50%;
  background: #ff7030;
  left: calc(25% + var(--s) * 25%);
  bottom: 35%;
  box-shadow: 0 0 4px #ff9060;
  animation: sparkFloat 1.8s ease-out infinite;
  animation-delay: calc(var(--s) * 0.6s);
}
.bg-fire:hover .fspark { opacity: 0; animation-play-state: paused; }
@keyframes sparkFloat {
  0%   { transform: translate(0,0) scale(1); opacity: .9; }
  100% { transform: translate(calc((var(--s) - 1) * 14px), -55px) scale(0); opacity: 0; }
}
.damper-tag {
  font-size: .62rem;
  font-weight: 700;
  letter-spacing: .12em;
  color: #ef4444;
  transition: color .4s ease;
}
.bg-fire:hover .damper-tag { color: #22c55e; }

/* === 6. IAQ GAUGE === */
.iaq-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
}
.iaq-gauge {
  position: relative;
  width: 210px;
  height: 115px;
  overflow: hidden;
}
.gauge-arc {
  position: absolute;
  bottom: 0;
  left: 0; right: 0;
  height: 210px;
  border-radius: 50% 50% 0 0 / 100% 100% 0 0;
  background: conic-gradient(
    from 270deg at 50% 100%,
    #ef4444 0deg 54deg,
    #f97316 54deg 81deg,
    #eab308 81deg 108deg,
    #22c55e 108deg 162deg,
    transparent 162deg
  );
  -webkit-mask: radial-gradient(circle at 50% 100%, transparent 68px, black 70px);
  mask: radial-gradient(circle at 50% 100%, transparent 68px, black 70px);
}
.gauge-needle {
  position: absolute;
  bottom: 2px;
  left: 50%;
  width: 3px;
  height: 92px;
  background: linear-gradient(0deg, #ffffff, #cccccc 80%, transparent);
  transform-origin: bottom center;
  transform: translateX(-50%) rotate(-72deg);
  border-radius: 3px 3px 0 0;
  transition: transform .85s cubic-bezier(.4,0,.2,1);
  box-shadow: 0 0 5px rgba(255,255,255,.25);
}
.bg-air:hover .gauge-needle { transform: translateX(-50%) rotate(14deg); }
.gauge-center {
  position: absolute;
  bottom: -5px;
  left: 50%;
  transform: translateX(-50%);
  width: 18px; height: 18px;
  border-radius: 50%;
  background: radial-gradient(circle, #ddd, #aaa);
  border: 3px solid #888;
  z-index: 2;
}
.gauge-labels {
  position: absolute;
  bottom: 0;
  left: 6px; right: 6px;
  display: flex;
  justify-content: space-between;
}
.gauge-bad  { font-size: .55rem; font-weight: 700; color: #ef4444; }
.gauge-good { font-size: .55rem; font-weight: 700; color: #22c55e; }
.iaq-reading {
  font-size: .9rem;
  font-weight: 700;
  letter-spacing: .06em;
  color: #ef4444;
  font-family: 'Courier New', monospace;
  transition: color .7s ease;
}
.bg-air:hover .iaq-reading { color: #22c55e; }
.iaq-tag {
  font-size: .62rem;
  font-weight: 700;
  letter-spacing: .12em;
  color: rgba(255,255,255,.38);
  transition: color .4s ease;
}
.bg-air:hover .iaq-tag { color: #22c55e; }

/* === Homepage card scale — fit interactive elements to 220px card height === */
.service-img .filter-wrap  { transform: scale(0.72); transform-origin: center center; }
.service-img .fan-wrap     { transform: scale(0.72); transform-origin: center center; }
.service-img .indust-wrap  { transform: scale(0.72); transform-origin: center center; }
.service-img .mini-vent-outer { transform: scale(0.72); transform-origin: center center; }
.service-img .damper-wrap  { transform: scale(0.72); transform-origin: center center; }
.service-img .iaq-wrap     { transform: scale(0.72); transform-origin: center center; }
/* IAQ reading counter on homepage — target any .iaq-reading inside service-img */
.service-img.bg-air:hover .iaq-reading { color: #22c55e; }

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 900px) {
  .service-row, .about-intro, .contact-layout { grid-template-columns: 1fr; }
  .service-row.reverse { direction: ltr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .process-steps { gap: 8px; }
  .process-arrow { display: none; }
  .hero-inner { flex-direction: column; gap: 48px; }
  .hero-3d-wrap { width: 260px; height: 260px; }
  .duct-box { width: 180px; height: 108px; }
  .face-front, .face-back { width: 180px; height: 108px; transform: translateZ(72px); }
  .face-back { transform: translateZ(-72px) rotateY(180deg); }
  .face-top { width: 180px; height: 144px; transform: translateY(-54px) rotateX(90deg); }
  .face-bottom { width: 180px; height: 144px; transform: translateY(54px) rotateX(-90deg); }
  .face-left { width: 144px; height: 108px; transform: translateX(-72px) rotateY(-90deg); }
  .face-right { width: 144px; height: 108px; transform: translateX(108px) rotateY(90deg); }
  .duct-opening { width: 72px; height: 72px; }
}
@media (max-width: 640px) {
  .nav-toggle { display: block; }
  .nav-links { display: none; flex-direction: column; position: absolute; top: 68px; left: 0; right: 0; background: var(--white); padding: 16px 24px 24px; border-bottom: 1px solid var(--border); box-shadow: 0 8px 24px rgba(0,0,0,.1); z-index: 99; }
  .nav-links.open { display: flex; }
  .nav-links a { width: 100%; }
  .nav-links .btn { width: 100%; justify-content: center; }
  .hero { padding: 70px 0 56px; min-height: unset; }
  .hero-stats { gap: 24px; }
  .section { padding: 60px 0; }
  .trust-inner { gap: 16px; }
  .cta-inner { flex-direction: column; text-align: center; }
  .cta-actions { justify-content: center; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .features-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .contact-form-wrap { padding: 24px; }
}