/* ============================================================
   GASFITER CERTIFICADO — sistema de diseño
   Base grafito/acero + cobre + azul llama de gas.
   Motivo de firma: esquema de cañería tipo plano técnico.
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Big+Shoulders+Display:wght@600;700;800&family=Inter:wght@400;500;600;700&family=IBM+Plex+Mono:wght@500;600&display=swap');

:root{
  /* Color */
  --graphite-900:#12161A;
  --graphite-800:#1B2126;
  --graphite-750:#20272D;
  --graphite-700:#262E35;
  --graphite-600:#333D45;
  --copper:#B5651D;
  --copper-light:#D98A4B;
  --copper-dim:#8A4E17;
  --gasblue:#3E92B5;
  --gasblue-dark:#2A6E8C;
  --paper:#F3EFE7;
  --paper-dim:#B9BEC2;
  --paper-mute:#7C848B;
  --ok:#5C8A5C;

  /* Type */
  --font-display:'Big Shoulders Display', system-ui, sans-serif;
  --font-body:'Inter', system-ui, -apple-system, sans-serif;
  --font-mono:'IBM Plex Mono', ui-monospace, monospace;

  /* Layout */
  --maxw:1180px;
  --radius:6px;
  --border:1px solid var(--graphite-600);
}

*,*::before,*::after{box-sizing:border-box;}
html{scroll-behavior:smooth;}
@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto;}
  *,*::before,*::after{animation-duration:0.001ms !important; animation-iteration-count:1 !important; transition-duration:0.001ms !important; scroll-behavior:auto !important;}
}

html{
  max-width:100%;
}

body{
  margin:0;
  max-width:100%;
  overflow-x:hidden;
  position:relative;
  background:var(--graphite-900);
  color:var(--paper);
  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{list-style:none;margin:0;padding:0;}

.wrap{max-width:var(--maxw);margin:0 auto;padding:0 24px;}

h1,h2,h3,h4{
  font-family:var(--font-display);
  font-weight:700;
  text-transform:uppercase;
  letter-spacing:0.01em;
  line-height:1.05;
  margin:0 0 0.5em;
  color:var(--paper);
}
h1{font-size:clamp(2.6rem,6vw,4.6rem); font-weight:800;}
h2{font-size:clamp(1.8rem,4vw,2.7rem);}
h3{font-size:clamp(1.25rem,2.4vw,1.6rem);}

p{margin:0 0 1em;color:var(--paper-dim);}
strong{color:var(--paper);}

.lede{font-size:1.15rem;color:var(--paper-dim);max-width:60ch;}

.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:8px;
  font-family:var(--font-mono);
  font-size:0.78rem;
  letter-spacing:0.08em;
  text-transform:uppercase;
  color:var(--gasblue);
  margin-bottom:14px;
}
.eyebrow::before{
  content:"";
  width:18px;height:1px;
  background:var(--gasblue);
  display:inline-block;
}

.tag-code{
  font-family:var(--font-mono);
  font-size:0.72rem;
  letter-spacing:0.03em;
  color:var(--copper-light);
  background:rgba(181,101,29,0.12);
  border:1px solid rgba(181,101,29,0.35);
  padding:3px 8px;
  border-radius:3px;
  display:inline-block;
}

/* ---------- Buttons ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  gap:10px;
  font-family:var(--font-body);
  font-weight:600;
  font-size:0.95rem;
  padding:14px 24px;
  border-radius:var(--radius);
  border:1px solid transparent;
  cursor:pointer;
  transition:transform .15s ease, background .2s ease, border-color .2s ease;
}
.btn:hover{transform:translateY(-1px);}
.btn:focus-visible{outline:2px solid var(--gasblue); outline-offset:3px;}
.btn-primary{background:var(--copper); color:#161311;}
.btn-primary:hover{background:var(--copper-light);}
.btn-ghost{background:transparent; color:var(--paper); border-color:var(--graphite-600);}
.btn-ghost:hover{border-color:var(--gasblue);}
.btn-block{width:100%; justify-content:center;}

/* ---------- Header ---------- */
.site-header{
  position:sticky; top:0; z-index:50;
  background:rgba(18,22,26,0.92);
  backdrop-filter:blur(8px);
  border-bottom:var(--border);
}
body.nav-open .site-header{
  backdrop-filter:none;
  -webkit-backdrop-filter:none;
}
.site-header .wrap{
  display:flex; align-items:center; justify-content:space-between;
  padding-top:14px; padding-bottom:14px;
}
.brand{display:flex; align-items:center; gap:10px; font-family:var(--font-display); font-size:1.25rem; text-transform:uppercase; letter-spacing:0.02em;}
.brand .mark{color:var(--copper);}
.brand small{display:block; font-family:var(--font-mono); font-size:0.6rem; letter-spacing:0.1em; color:var(--gasblue); text-transform:uppercase;}

.nav-main{display:flex; gap:28px;}
.nav-main a{font-size:0.92rem; font-weight:500; color:var(--paper-dim); position:relative; padding:4px 0;}
.nav-main a:hover, .nav-main a[aria-current="page"]{color:var(--paper);}
.nav-main a[aria-current="page"]::after{
  content:""; position:absolute; left:0; right:0; bottom:-4px; height:2px; background:var(--copper);
}

.nav-cta{display:flex; align-items:center; gap:14px;}
.nav-toggle{display:none; background:none; border:1px solid var(--graphite-600); border-radius:4px; padding:10px 13px; font-size:1.05rem; color:var(--paper); min-height:44px;}

@media (max-width:900px){
  .nav-main{
    position:fixed; top:var(--header-h, 73px); left:0; right:0; bottom:0; background:var(--graphite-900);
    flex-direction:column; padding:32px 24px; gap:22px; transform:translateX(100%);
    transition:transform .25s ease; overflow-y:auto; -webkit-overflow-scrolling:touch;
    overscroll-behavior:contain;
  }
  .nav-main.open{transform:translateX(0);}
  .nav-main a{padding:6px 0; font-size:1rem;}
  .nav-toggle{display:block;}
  .nav-cta .btn-ghost{display:none;}
}

/* ---------- Pipe schematic (signature element) ---------- */
.pipe-line{
  width:100%; display:block;
  stroke:var(--graphite-600);
  stroke-width:2;
  fill:none;
}
.pipe-line .run{stroke:var(--copper); stroke-dasharray:1400; stroke-dashoffset:1400; transition:stroke-dashoffset 1.6s ease;}
.pipe-line.in-view .run{stroke-dashoffset:0;}
.pipe-line .joint{fill:var(--gasblue);}
.pipe-divider{position:relative; height:46px; margin:0 auto; max-width:var(--maxw); opacity:0.9;}

/* ---------- Hero ---------- */
.hero{
  position:relative;
  padding:88px 0 60px;
  background:
    radial-gradient(ellipse at 15% 0%, rgba(62,146,181,0.14), transparent 55%),
    radial-gradient(ellipse at 90% 20%, rgba(181,101,29,0.12), transparent 50%),
    var(--graphite-900);
  border-bottom:var(--border);
  overflow:hidden;
}
.hero-grid{display:grid; grid-template-columns:1.1fr 0.9fr; gap:48px; align-items:center;}
@media (max-width:920px){.hero-grid{grid-template-columns:1fr;}}

.hero-badges{display:flex; flex-wrap:wrap; gap:10px; margin:22px 0 28px;}
.hero-badge{
  display:flex; align-items:center; gap:8px;
  font-size:0.82rem; color:var(--paper-dim);
  border:1px solid var(--graphite-600); border-radius:20px; padding:7px 14px;
}
.hero-badge .dot{width:7px;height:7px;border-radius:50%; background:var(--ok);}
.hero-ctas{display:flex; gap:14px; flex-wrap:wrap;}

.hero-visual{
  border:var(--border); border-radius:8px; background:var(--graphite-800);
  padding:20px; position:relative;
}
.hero-visual svg{width:100%; height:auto;}
.hero-visual .caption{font-family:var(--font-mono); font-size:0.72rem; color:var(--paper-mute); margin-top:12px; text-align:center;}

/* ---------- Sections ---------- */
section{padding:76px 0;}
.section-head{max-width:640px; margin-bottom:44px;}
.section-alt{background:var(--graphite-800); border-top:var(--border); border-bottom:var(--border);}

/* ---------- Services grid ---------- */
.service-grid{display:grid; grid-template-columns:repeat(3,1fr); gap:20px;}
@media (max-width:900px){.service-grid{grid-template-columns:repeat(2,1fr);}}
@media (max-width:600px){.service-grid{grid-template-columns:1fr;}}

.service-card{
  border:var(--border); border-radius:8px; padding:26px; background:var(--graphite-800);
  transition:border-color .2s ease, transform .2s ease;
}
.service-card:hover{border-color:var(--copper); transform:translateY(-3px);}
.service-card h3{margin:14px 0 8px; font-size:1.15rem;}
.service-card p{font-size:0.92rem; margin-bottom:10px;}
.service-card .materials{font-family:var(--font-mono); font-size:0.7rem; color:var(--gasblue); letter-spacing:0.02em;}
.service-icon{color:var(--copper);}

/* ---------- Gallery ---------- */
.gallery{display:grid; grid-template-columns:repeat(3,1fr); gap:16px;}
@media (max-width:800px){.gallery{grid-template-columns:repeat(2,1fr);}}
@media (max-width:520px){.gallery{grid-template-columns:1fr;}}
.gallery-item{
  position:relative; overflow:hidden; border-radius:8px; border:var(--border);
  aspect-ratio:4/3; cursor:zoom-in; background:var(--graphite-800);
}
.gallery-item img{width:100%;height:100%;object-fit:cover; transition:transform .5s ease, filter .5s ease; filter:grayscale(25%);}
.gallery-item:hover img{transform:scale(1.06); filter:grayscale(0%);}
.gallery-item .label{
  position:absolute; left:0; right:0; bottom:0; padding:10px 12px;
  font-size:0.78rem; background:linear-gradient(0deg, rgba(0,0,0,0.75), transparent);
  opacity:0; transition:opacity .3s ease;
}
.gallery-item:hover .label{opacity:1;}

.lightbox{
  position:fixed; inset:0; background:rgba(10,12,14,0.92); z-index:100;
  display:none; align-items:center; justify-content:center; padding:40px;
}
.lightbox.open{display:flex;}
.lightbox img{max-height:86vh; max-width:100%; border-radius:6px;}
.lightbox-close{position:absolute; top:24px; right:28px; background:none; border:1px solid var(--graphite-600); color:var(--paper); border-radius:4px; padding:8px 12px; cursor:pointer;}

/* ---------- Reviews ---------- */
.reviews-track{display:flex; gap:18px; overflow-x:auto; padding-bottom:8px; scroll-snap-type:x mandatory;}
.review-card{
  scroll-snap-align:start; min-width:300px; max-width:340px;
  border:var(--border); border-radius:8px; padding:22px; background:var(--graphite-800);
}
.stars{color:var(--copper-light); letter-spacing:2px; margin-bottom:10px; font-size:0.95rem;}
.review-card p{font-size:0.92rem; color:var(--paper-dim); font-style:italic;}
.review-author{display:flex; align-items:center; gap:10px; margin-top:14px;}
.review-avatar{width:34px;height:34px;border-radius:50%; background:var(--graphite-700); display:flex; align-items:center; justify-content:center; font-family:var(--font-mono); font-size:0.8rem; color:var(--gasblue);}
.review-author span{font-size:0.85rem; color:var(--paper);}
.review-author small{display:block; font-size:0.75rem; color:var(--paper-mute);}

/* ---------- Certification panel ---------- */
.cert-panel{display:grid; grid-template-columns:1fr 1fr; gap:40px; align-items:center;}
@media (max-width:880px){.cert-panel{grid-template-columns:1fr;}}
.cert-card{border:var(--border); border-radius:8px; padding:28px; background:var(--graphite-800);}
.cert-row{display:flex; justify-content:space-between; padding:10px 0; border-bottom:1px dashed var(--graphite-600); font-size:0.9rem;}
.cert-row:last-child{border-bottom:none;}
.cert-row span:first-child{color:var(--paper-mute);}
.cert-row span:last-child{color:var(--paper); font-family:var(--font-mono); font-size:0.85rem;}
.qr-box{border:var(--border); border-radius:8px; padding:20px; background:var(--graphite-900); text-align:center;}
.qr-box img{margin:0 auto 12px; border-radius:4px; width:160px;}

/* ---------- FAQ ---------- */
.faq-list{max-width:800px;}
.faq-item{border-bottom:var(--border); padding:6px 0;}
.faq-item summary{
  cursor:pointer; padding:16px 0; font-weight:600; color:var(--paper);
  display:flex; justify-content:space-between; align-items:center; list-style:none;
}
.faq-item summary::-webkit-details-marker{display:none;}
.faq-item summary::after{content:"+"; font-family:var(--font-mono); color:var(--copper); font-size:1.3rem;}
.faq-item[open] summary::after{content:"−";}
.faq-item p{padding-bottom:18px; font-size:0.95rem;}

/* ---------- Blog ---------- */
.post-grid{display:grid; grid-template-columns:repeat(3,1fr); gap:22px;}
@media (max-width:900px){.post-grid{grid-template-columns:repeat(2,1fr);}}
@media (max-width:600px){.post-grid{grid-template-columns:1fr;}}
.post-card{border:var(--border); border-radius:8px; overflow:hidden; background:var(--graphite-800); transition:border-color .2s ease;}
.post-card:hover{border-color:var(--gasblue);}
.post-card .post-body{padding:20px;}
.post-card .meta{font-family:var(--font-mono); font-size:0.72rem; color:var(--paper-mute); margin-bottom:8px;}
.post-card h3{font-size:1.05rem; margin:0 0 8px;}
.post-card p{font-size:0.88rem;}

.article-body{max-width:70ch; margin:0 auto;}
.article-body h2{margin-top:1.6em;}
.article-body h3{margin-top:1.3em;}
.article-body ul{list-style:disc; padding-left:1.3em; margin-bottom:1em;}
.article-body ul li{margin-bottom:0.4em; color:var(--paper-dim);}
.answer-box{
  border-left:3px solid var(--gasblue); background:var(--graphite-800);
  padding:18px 22px; border-radius:0 8px 8px 0; margin:24px 0;
}
.answer-box p{margin:0; color:var(--paper);}
.answer-box .eyebrow{margin-bottom:8px;}

/* ---------- Comuna page ---------- */
.local-strip{display:flex; flex-wrap:wrap; gap:10px; margin:20px 0;}
.local-strip a{
  font-size:0.82rem; border:1px solid var(--graphite-600); border-radius:20px; padding:6px 14px; color:var(--paper-dim);
}
.local-strip a:hover{border-color:var(--copper); color:var(--paper);}

/* ---------- CTA band ---------- */
.cta-band{
  background:linear-gradient(120deg, var(--graphite-800), var(--graphite-900));
  border-top:var(--border); border-bottom:var(--border);
  text-align:center;
}
.cta-band h2{margin-bottom:10px;}
.cta-band .lede{margin:0 auto 28px;}

/* ---------- Footer ---------- */
footer{padding:50px 0 30px; border-top:var(--border);}
.footer-grid{display:grid; grid-template-columns:1.4fr 1fr 1fr; gap:36px; margin-bottom:36px;}
@media (max-width:760px){.footer-grid{grid-template-columns:1fr; gap:28px;}}
.footer-grid h4{font-size:0.85rem; color:var(--paper); text-transform:uppercase; letter-spacing:0.06em; margin-bottom:14px; font-family:var(--font-mono); font-weight:600;}
.footer-grid a, .footer-grid p{font-size:0.88rem; color:var(--paper-dim); display:block; margin-bottom:8px;}
.footer-grid a:hover{color:var(--copper-light);}
.footer-bottom{
  display:flex; justify-content:space-between; flex-wrap:wrap; gap:10px;
  font-size:0.78rem; color:var(--paper-mute); border-top:1px solid var(--graphite-700); padding-top:22px;
}

/* ---------- Utility ---------- */
.reveal{opacity:0; transform:translateY(16px); transition:opacity .6s ease, transform .6s ease;}
.reveal.in-view{opacity:1; transform:translateY(0);}
.skip-link{
  position:absolute; left:-999px; top:0; background:var(--copper); color:#141110; padding:10px 16px; z-index:200;
}
.skip-link:focus{left:16px; top:16px;}
.breadcrumbs{font-size:0.8rem; color:var(--paper-mute); margin-bottom:18px;}
.breadcrumbs a{color:var(--paper-mute);}
.breadcrumbs a:hover{color:var(--copper-light);}
.page-hero{padding:56px 0 40px; border-bottom:var(--border);}

/* ---------- Small phones (≤480px) ---------- */
@media (max-width:480px){
  .wrap{padding:0 18px;}
  h1{font-size:2.15rem; letter-spacing:0;}
  h2{font-size:1.55rem;}
  .hero{padding:48px 0 40px;}
  section{padding:52px 0;}
  .hero-ctas{flex-direction:column; align-items:stretch;}
  .hero-ctas .btn{justify-content:center;}
  .cta-band .btn{width:100%; justify-content:center;}
  .service-card{padding:20px;}
  .review-card{min-width:82vw; max-width:82vw;}
  .gallery{gap:12px;}
  .cert-card{padding:20px;}
  .cert-row{flex-direction:column; gap:4px; align-items:flex-start;}
  .footer-grid{gap:26px;}
  .faq-item summary{font-size:0.95rem; gap:10px;}
  .brand small{letter-spacing:0.04em;}
  .hero-visual{padding:14px;}
  .visual-label{display:none;}
}