:root{
  --navy:#071f3d;
  --navy2:#0d335b;
  --blue:#1672b8;
  --sky:#edf6fc;
  --sky2:#dfeef8;
  --ice:#f6fafc;
  --accent:#ffd35a;
  --ink:#111827;
  --muted:#475569;
  --line:#d6e2ea;
  --radius:18px;
  --shadow:0 12px 30px rgba(7,31,61,.10);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;max-width:100%;overflow-x:hidden}
body{
  margin:0;
  font-family:Arial,Helvetica,sans-serif;
  color:var(--ink);
  background:#f3f7fa;
  line-height:1.65;
  font-size:18px;
  max-width:100%;
  overflow-x:hidden;
}
a{color:var(--blue);text-decoration:none}
a:hover{text-decoration:underline}
img,video,iframe{max-width:100%;height:auto}
.wrap{width:min(1180px,calc(100% - 36px));margin:auto}
.topbar{background:#04182e;color:#fff;font-size:15px}
.topbar .wrap{display:flex;gap:18px;justify-content:space-between;align-items:center;padding:8px 0}
.topbar a{color:#fff;font-weight:800}
.header{
  background:#fff;
  border-bottom:1px solid var(--line);
  position:sticky;
  top:0;
  z-index:100;
  box-shadow:0 4px 18px rgba(7,31,61,.05)
}
.nav{display:flex;align-items:center;justify-content:space-between;gap:22px;padding:13px 0;position:relative}
.brand{display:flex;align-items:center;gap:10px;color:var(--navy);font-weight:900;font-size:24px;min-width:0}
.brand>span:last-child{min-width:0}
.brand small{display:block;font-size:11px;letter-spacing:1.6px;color:var(--blue)}
.logo-mark{
  width:42px;height:42px;border-radius:50%;
  display:grid;place-items:center;flex:0 0 42px;
  background:linear-gradient(145deg,var(--blue),var(--navy));color:#fff;font-size:24px
}
.menu{display:flex;gap:17px;align-items:center;font-size:16px;font-weight:800}
.menu a{color:var(--navy);white-space:nowrap}
.cta{
  display:inline-flex;align-items:center;justify-content:center;
  background:var(--accent);color:#17202b!important;font-weight:900;
  padding:12px 18px;border-radius:999px;text-decoration:none!important
}
.mobile-menu-toggle{
  display:none;
  width:48px;height:48px;flex:0 0 48px;
  border:0;border-radius:11px;background:var(--navy);cursor:pointer;
  align-items:center;justify-content:center;flex-direction:column;gap:5px;
  padding:10px
}
.mobile-menu-toggle span{
  display:block!important;
  width:27px!important;height:3px!important;
  background:#fff!important;border-radius:3px!important;
  opacity:1!important;transform:none;
  transition:transform .18s ease,opacity .18s ease
}
.mobile-menu-toggle[aria-expanded="true"] span:nth-child(1){transform:translateY(8px) rotate(45deg)}
.mobile-menu-toggle[aria-expanded="true"] span:nth-child(2){opacity:0!important}
.mobile-menu-toggle[aria-expanded="true"] span:nth-child(3){transform:translateY(-8px) rotate(-45deg)}

.hero,.page-hero{
  background:linear-gradient(135deg,var(--navy),var(--blue));
  color:#fff
}
.hero{padding:72px 0}
.page-hero{padding:54px 0}
.hero-grid{display:grid;grid-template-columns:minmax(0,1.18fr) minmax(320px,.82fr);gap:40px;align-items:center}
.eyebrow{text-transform:uppercase;letter-spacing:2px;font-size:14px;font-weight:900;color:#c8e5fb}
.hero h1{font-size:clamp(42px,6vw,70px);line-height:1.04;margin:.3rem 0 1rem;letter-spacing:-1.5px}
.hero>*,.page-hero>*{min-width:0}
.hero p,.page-hero p{font-size:20px;color:#edf7ff}
.hero-card{
  background:#fff;color:var(--ink);padding:24px;border-radius:var(--radius);box-shadow:var(--shadow)
}
.hero-card h2{color:var(--navy);margin-top:0}
.hero-card p,.hero-card strong,.hero-card span,.hero-card a{
  color:#000!important;opacity:1!important;-webkit-text-fill-color:#000!important
}
.hero-card-photo{display:block;width:100%;aspect-ratio:16/9;object-fit:cover;border-radius:14px;margin:0 0 17px}
.btns{display:flex;gap:12px;flex-wrap:wrap;margin-top:24px}
.btn{display:inline-flex;align-items:center;justify-content:center;padding:14px 20px;border-radius:999px;font-weight:900;background:#fff;color:var(--navy);text-decoration:none!important}
.btn.alt{background:var(--accent);color:#1f2730}

section{padding:60px 0;background:#fff}
main>section:nth-of-type(even):not(.hero):not(.page-hero):not(.dark){background:var(--sky)}
main>section:nth-of-type(3n):not(.hero):not(.page-hero):not(.dark){background:var(--ice)}
.soft{background:var(--sky)!important}
.dark{background:var(--navy)!important;color:#fff}
.dark h2,.dark h3,.dark a{color:#fff}
.dark p{color:#e4f0f9}
.trust{background:var(--sky2)!important;border-bottom:1px solid var(--line)}
.trust .wrap{display:grid;grid-template-columns:repeat(4,1fr);gap:1px;background:var(--line)}
.trust div{background:#f8fcff;padding:17px;text-align:center;font-weight:800;color:var(--navy)}

.section-head{max-width:760px;margin-bottom:30px}
.section-head h2{font-size:clamp(32px,4vw,46px);line-height:1.1;margin:0 0 12px;color:var(--navy)}
.section-head p{color:var(--muted)}
.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}
.card{
  border:1px solid var(--line);border-radius:var(--radius);padding:24px;
  background:#fff;box-shadow:0 8px 22px rgba(7,31,61,.06);min-width:0
}
.card h2,.card h3{color:var(--navy)}
.card p{color:#334155}
.content{max-width:900px}
.content h2{font-size:34px;color:var(--navy);margin-top:42px}
.content h3{color:var(--navy)}
.checklist{padding-left:1.2rem}.checklist li{margin:.5rem 0}
.notice{padding:14px 16px;border-left:4px solid var(--blue);background:#eef6fb;color:#263648}
.faq details{border:1px solid var(--line);border-radius:14px;padding:16px 18px;background:#fff;margin-bottom:12px}
.faq summary{font-weight:900;color:var(--navy);cursor:pointer}
.breadcrumbs{font-size:14px;margin-bottom:18px;color:#d6e8f7}
.breadcrumbs a{color:#fff}
.page-hero h1{font-size:clamp(38px,5vw,60px);line-height:1.07;margin:.4rem 0}
.page-hero p{max-width:800px}

.form{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:16px;width:100%}
.form>div{min-width:0}
.form label{font-weight:800;display:block;min-width:0}
.form input,.form select,.form textarea{
  display:block;width:100%;min-width:0;max-width:100%;
  padding:13px 14px;border:1px solid #aebfcd;border-radius:10px;
  font:inherit;margin-top:6px;background:#fff;color:#111
}
.form textarea{min-height:150px;resize:vertical}
.form .wide{grid-column:1/-1}
.form button{border:0;cursor:pointer;font-size:18px}
.contact-grid{display:grid;grid-template-columns:minmax(0,1.3fr) minmax(260px,.7fr);gap:20px;align-items:start}
.contact-grid>*{min-width:0}

.brand-photo,.boiler-product-figure{
  width:min(100%,760px);margin:22px auto 30px;padding:18px;
  background:#fff;border:1px solid var(--line);border-radius:16px;box-shadow:var(--shadow);text-align:center
}
.brand-photo img,.boiler-product-figure img,.real-product-photo{
  display:block;width:100%;max-width:620px;height:430px;object-fit:contain;margin:0 auto;background:#fff
}
.brand-photo figcaption,.boiler-product-label{color:#111;margin-top:12px;font-weight:800}
.manufacturer-source{font-size:14px;color:#334155;margin-top:8px}
.manufacturer-source a{text-decoration:underline}

.footer{background:#04182e;color:#d8e6f2;padding:46px 0 88px}
.footer-grid{display:grid;grid-template-columns:1.2fr 1fr 1fr 1fr;gap:28px}
.footer h3{color:#fff}.footer a{color:#d8e6f2}.license{font-weight:900;color:#fff}
.local-architecture-links{width:min(1180px,calc(100% - 36px));margin:22px auto 0;line-height:1.8}
.mobile-call{display:none;position:fixed;left:10px;right:10px;bottom:10px;z-index:120;background:var(--accent);color:#111!important;font-weight:900;text-align:center;padding:13px;border-radius:999px;box-shadow:var(--shadow)}

@media(max-width:900px){
  body{background:#eaf2f7}
  .wrap{width:min(100% - 22px,1180px)}
  .topbar .wrap{flex-wrap:wrap;justify-content:center;text-align:center;gap:3px 10px}
  .topbar .wrap>span:first-child{display:none}
  .nav{padding:10px 0}
  .brand{font-size:19px;max-width:calc(100% - 62px)}
  .brand small{font-size:9px;letter-spacing:1.1px}
  .logo-mark{width:38px;height:38px;flex-basis:38px;font-size:21px}
  .mobile-menu-toggle{display:flex!important;margin-left:auto}

  /* Compact dropdown menu fully contained inside the viewport */
  .menu{
    display:none!important;
    position:absolute!important;
    top:calc(100% + 7px)!important;
    left:0!important;
    right:0!important;
    width:auto!important;
    max-width:100%!important;
    max-height:72vh!important;
    overflow-y:auto!important;
    overflow-x:hidden!important;
    flex-direction:column!important;
    align-items:stretch!important;
    gap:0!important;
    padding:7px!important;
    margin:0!important;
    background:#fff!important;
    border:1px solid var(--line)!important;
    border-radius:14px!important;
    box-shadow:0 16px 38px rgba(7,31,61,.22)!important;
  }
  .menu.mobile-open{display:flex!important}
  .menu>a{
    display:block!important;width:100%!important;max-width:100%!important;
    min-height:46px!important;padding:12px 13px!important;margin:0!important;
    white-space:normal!important;color:var(--navy)!important;
    border-bottom:1px solid #edf2f6!important;font-size:16px!important;line-height:1.25!important
  }
  .menu>a:last-child{border-bottom:0!important}
  .menu>a.cta{margin-top:6px!important;text-align:center!important;background:var(--accent)!important}

  .hero{padding:44px 0}
  .page-hero{padding:42px 0}
  .hero-grid,.footer-grid,.contact-grid,.grid{grid-template-columns:minmax(0,1fr)!important}
  .hero-grid{gap:25px}
  .hero h1{font-size:clamp(34px,9vw,46px);letter-spacing:-.8px}
  .hero p,.page-hero p{font-size:18px}
  .hero-card{padding:17px}
  .trust .wrap{grid-template-columns:1fr 1fr}
  section{padding:46px 0}
  main>section:not(.hero):not(.page-hero):not(.dark){border-top:1px solid rgba(7,31,61,.05)}
  .card{padding:19px}
  .form{grid-template-columns:minmax(0,1fr)!important;gap:14px}
  .form .wide{grid-column:auto}
  .form input,.form select,.form textarea{font-size:16px!important}
  .form button,.form .cta{width:100%!important;min-height:50px}
  .brand-photo,.boiler-product-figure{padding:12px;width:100%}
  .brand-photo img,.boiler-product-figure img,.real-product-photo{height:auto;max-height:390px}
  .footer-grid{gap:15px}
  .footer{padding-top:40px}
  .mobile-call{display:block}
}

@media(max-width:520px){
  body{font-size:17px}
  .wrap{width:calc(100% - 18px)}
  .hero h1{font-size:36px}
  .page-hero h1{font-size:34px}
  .btns{display:grid;grid-template-columns:1fr;width:100%}
  .btns .btn,.btn{width:100%;text-align:center}
  .trust .wrap{grid-template-columns:1fr}
  .mobile-menu-toggle{width:44px;height:44px;flex-basis:44px;padding:8px}
  .mobile-menu-toggle span{width:25px!important}
  .mobile-call{left:7px;right:7px;padding:12px 9px;font-size:16px}
  .local-architecture-links{width:calc(100% - 18px)}
}


/* ===== FINAL MOBILE RESPONSIVE SAFETY NET ===== */
html,body{width:100%;max-width:100%;overflow-x:hidden}
*,*::before,*::after{box-sizing:border-box}
img,svg,video,canvas,iframe{max-width:100%;height:auto}
table{max-width:100%}
pre,code{white-space:pre-wrap;overflow-wrap:anywhere}
.wrap,.container,main,section,article,aside,form{min-width:0}
input,select,textarea,button{min-width:0;max-width:100%;box-sizing:border-box}

@media(max-width:900px){
  .nav{position:relative!important;width:100%!important}
  .mobile-menu-toggle{
    display:flex!important;
    position:relative!important;
    z-index:202!important;
  }
  .mobile-menu-toggle span{
    display:block!important;
    width:26px!important;
    min-width:26px!important;
    height:3px!important;
    min-height:3px!important;
    background:#fff!important;
  }
  .menu{
    position:absolute!important;
    top:calc(100% + 6px)!important;
    left:0!important;
    right:0!important;
    width:100%!important;
    max-width:100%!important;
    min-width:0!important;
    overflow-x:hidden!important;
    transform:none!important;
  }
  .menu.mobile-open{display:flex!important}
  .menu>a{
    width:100%!important;
    max-width:100%!important;
    min-width:0!important;
    white-space:normal!important;
    overflow-wrap:anywhere!important;
  }
  form,.form,.contact-grid,.hero-grid,.grid{
    max-width:100%!important;
    min-width:0!important;
  }
  .form{
    grid-template-columns:minmax(0,1fr)!important;
  }
  .form>*,
  .form .wide{
    grid-column:1/-1!important;
    width:100%!important;
    min-width:0!important;
  }
  .form input,.form select,.form textarea,
  form input,form select,form textarea{
    width:100%!important;
    max-width:100%!important;
    min-width:0!important;
  }
}