/* ============================================================
   GUÍA FACTURA DE AIRE — sistema de diseño
   Paleta: cielo/azul técnico, tinta profunda, ámbar de aviso
   Tipografía: Space Grotesk (display) / Inter (texto) / IBM Plex Mono (datos)
   ============================================================ */

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

:root{
  --tinta: #101828;
  --tinta-suave: #475467;
  --azul-profundo: #0B2545;
  --azul: #1D4ED8;
  --azul-cielo: #3B82F6;
  --azul-claro: #DBEAFE;
  --cian: #0891B2;
  --ambar: #D97706;
  --ambar-claro: #FEF3C7;
  --crema: #F7F9FC;
  --crema-2: #EEF2F9;
  --blanco: #FFFFFF;
  --linea: rgba(16,24,40,0.10);
  --sombra: 0 18px 40px -20px rgba(11,37,69,0.30);
  --radio: 18px;
  --max: 1180px;
}

*{box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  margin:0;
  background:var(--crema);
  color:var(--tinta);
  font-family:'Inter',-apple-system,Segoe UI,sans-serif;
  font-size:17px;
  line-height:1.65;
  -webkit-font-smoothing:antialiased;
}
img,svg{max-width:100%;display:block;}
a{color:inherit;text-decoration:none;}
ul{margin:0;padding:0;list-style:none;}
.wrap{max-width:var(--max);margin:0 auto;padding:0 28px;}
.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;}

h1,h2,h3,h4{
  font-family:'Space Grotesk',Arial,sans-serif;
  font-weight:600;
  line-height:1.12;
  margin:0;
  color:var(--azul-profundo);
  letter-spacing:-0.01em;
}
.eyebrow{
  font-family:'IBM Plex Mono',monospace;
  font-size:12.5px;
  letter-spacing:0.14em;
  text-transform:uppercase;
  color:var(--azul);
  font-weight:600;
  display:inline-flex;
  align-items:center;
  gap:8px;
}
.eyebrow::before{
  content:"";
  width:18px;height:1px;background:var(--azul);
  display:inline-block;
}
p{margin:0 0 1em;}
.lede{font-size:1.12rem;color:var(--tinta-suave);max-width:60ch;}

.btn{
  display:inline-flex;align-items:center;gap:10px;
  padding:14px 26px;border-radius:12px;
  font-weight:600;font-size:0.98rem;
  border:1.5px solid transparent;
  cursor:pointer;transition:transform .18s ease, background .18s ease, color .18s ease, border-color .18s ease;
}
.btn-primary{background:var(--ambar);color:var(--blanco);}
.btn-primary:hover{transform:translateY(-2px);background:#C2670A;}
.btn-ghost{border-color:rgba(247,249,252,0.35);color:var(--crema);}
.btn-ghost:hover{border-color:var(--crema);transform:translateY(-2px);}
.btn-line{border-color:var(--linea);color:var(--azul-profundo);}
.btn-line:hover{border-color:var(--azul);color:var(--azul);}

/* ---------- HEADER ---------- */
.site-header{
  position:sticky;top:0;z-index:50;
  background:rgba(247,249,252,0.92);
  backdrop-filter:blur(8px);
  border-bottom:1px solid var(--linea);
}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:74px;}
.brand{display:flex;align-items:center;gap:10px;color:var(--azul-profundo);}
.brand-mark{color:var(--azul);display:flex;}
.brand-text{font-family:'Space Grotesk',sans-serif;font-size:1.12rem;font-weight:500;}
.brand-text strong{font-weight:700;}
.nav-list{display:flex;gap:28px;}
.nav-list a{font-weight:600;font-size:0.93rem;color:var(--tinta-suave);transition:color .15s;}
.nav-list a:hover{color:var(--azul);}
.nav-toggle{display:none;flex-direction:column;gap:5px;background:none;border:0;cursor:pointer;padding:8px;}
.nav-toggle span{width:24px;height:2px;background:var(--azul-profundo);border-radius:2px;}

/* ---------- HERO ---------- */
.hero{
  position:relative;
  background:radial-gradient(circle at 15% 15%, var(--azul), var(--azul-profundo) 65%);
  color:var(--crema);
  overflow:hidden;
  padding:96px 0 0;
}
.hero-inner{
  display:grid;grid-template-columns:1.05fr 0.95fr;gap:40px;
  align-items:center;
  position:relative;z-index:2;
}
.hero h1{
  color:var(--crema);
  font-size:clamp(2.4rem,4.6vw,3.8rem);
  margin:18px 0 22px;
}
.hero h1 em{color:#FCD34D;font-style:normal;}
.hero .lede{color:rgba(247,249,252,0.82);}
.hero-cta{display:flex;gap:14px;flex-wrap:wrap;margin-top:30px;}
.hero-stats{display:flex;gap:28px;margin-top:48px;flex-wrap:wrap;}
.hero-stats div{font-family:'IBM Plex Mono',monospace;}
.hero-stats b{display:block;font-size:1.4rem;color:#FCD34D;}
.hero-stats span{font-size:0.78rem;color:rgba(247,249,252,0.7);}

.hero-art{position:relative;height:400px;}
.hero-art svg{position:absolute;inset:0;width:100%;height:100%;}

.hero-disclaimer{
  margin-top:34px;padding:14px 18px;border-radius:12px;
  background:rgba(252,211,77,0.12);border:1px solid rgba(252,211,77,0.35);
  font-size:0.85rem;color:rgba(247,249,252,0.9);max-width:56ch;
}

/* ---------- PARTES DE LA FACTURA ---------- */
.partes{padding:90px 0 70px;}
.section-head{max-width:680px;margin-bottom:46px;}
.section-head h2{font-size:clamp(1.8rem,3.2vw,2.4rem);margin-top:14px;}

.factura-mock{
  display:grid;grid-template-columns:0.85fr 1.15fr;gap:34px;align-items:start;
  margin-bottom:10px;
}
.factura-visual{
  background:var(--blanco);border:1px solid var(--linea);border-radius:var(--radio);
  padding:26px;box-shadow:var(--sombra);position:sticky;top:100px;
}
.factura-visual .fv-row{
  display:flex;justify-content:space-between;align-items:center;
  padding:10px 0;border-bottom:1px dashed var(--linea);font-size:0.86rem;
}
.factura-visual .fv-row:last-child{border-bottom:0;}
.factura-visual .fv-row b{color:var(--azul-profundo);font-family:'IBM Plex Mono',monospace;font-size:0.8rem;}
.factura-visual .fv-total{
  margin-top:14px;padding:14px;border-radius:10px;background:var(--azul-claro);
  display:flex;justify-content:space-between;align-items:center;
  font-family:'IBM Plex Mono',monospace;font-weight:600;color:var(--azul-profundo);
}

.parte-list{display:flex;flex-direction:column;gap:18px;}
.parte-item{
  background:var(--blanco);border:1px solid var(--linea);border-radius:14px;
  padding:20px 22px;display:flex;gap:16px;
  transition:transform .18s ease, box-shadow .18s ease;
}
.parte-item:hover{transform:translateX(4px);box-shadow:var(--sombra);}
.parte-num{
  font-family:'IBM Plex Mono',monospace;font-weight:600;color:var(--ambar);
  font-size:0.85rem;flex-shrink:0;width:28px;
}
.parte-item h3{font-size:1.02rem;margin-bottom:6px;}
.parte-item p{font-size:0.92rem;color:var(--tinta-suave);margin:0;}

/* ---------- GLOSARIO ---------- */
.glosario{padding:70px 0;background:var(--crema-2);}
.glosario-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;}
.glos-card{
  background:var(--blanco);border-radius:14px;border:1px solid var(--linea);
  padding:22px;
}
.glos-term{
  font-family:'IBM Plex Mono',monospace;font-size:0.78rem;font-weight:600;
  color:var(--cian);text-transform:uppercase;letter-spacing:0.06em;margin-bottom:8px;display:block;
}
.glos-card h3{font-size:1.02rem;margin-bottom:8px;}
.glos-card p{font-size:0.9rem;color:var(--tinta-suave);margin:0;}

/* ---------- FAQ ---------- */
.faq{padding:90px 0;}
.faq-list{max-width:820px;}
.faq-item{
  border-bottom:1px solid var(--linea);padding:22px 0;
}
.faq-item summary{
  cursor:pointer;font-family:'Space Grotesk',sans-serif;font-weight:600;
  font-size:1.05rem;color:var(--azul-profundo);list-style:none;
  display:flex;justify-content:space-between;align-items:center;gap:16px;
}
.faq-item summary::-webkit-details-marker{display:none;}
.faq-item summary::after{
  content:"+";font-family:'IBM Plex Mono',monospace;font-size:1.3rem;color:var(--ambar);flex-shrink:0;
}
.faq-item[open] summary::after{content:"–";}
.faq-item p{margin-top:12px;color:var(--tinta-suave);font-size:0.96rem;max-width:70ch;}

/* ---------- CONSEJOS ---------- */
.consejos{padding:90px 0;background:var(--azul-profundo);color:var(--crema);}
.consejos .section-head h2{color:var(--crema);}
.consejos .eyebrow{color:#FCD34D;}
.consejos .eyebrow::before{background:#FCD34D;}
.consejos .lede{color:rgba(247,249,252,0.78);}
.consejo-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;}
.consejo-item{
  background:rgba(247,249,252,0.06);
  border:1px solid rgba(247,249,252,0.14);
  border-radius:16px;padding:24px;
}
.consejo-item h3{
  color:var(--crema);font-size:1rem;margin-bottom:10px;
  display:flex;align-items:center;gap:10px;
}
.consejo-item h3 .pn{
  font-family:'IBM Plex Mono',monospace;color:#FCD34D;font-size:0.78rem;
}
.consejo-item p{color:rgba(247,249,252,0.75);font-size:0.9rem;margin:0;}

.aviso-box{
  margin-top:46px;padding:20px 24px;border-radius:14px;
  background:rgba(252,211,77,0.1);border:1px solid rgba(252,211,77,0.35);
  font-size:0.9rem;color:rgba(247,249,252,0.9);
}
.aviso-box strong{color:#FCD34D;}

/* ---------- CTA ---------- */
.cta-final{padding:90px 0;text-align:center;}
.cta-final h2{font-size:clamp(1.9rem,3.6vw,2.6rem);margin-bottom:18px;}
.cta-final .lede{margin:0 auto 30px;}
.cta-final .hero-cta{justify-content:center;}

/* ---------- FOOTER ---------- */
.site-footer{background:var(--azul-profundo);color:rgba(247,249,252,0.82);padding:70px 0 0;}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:36px;padding-bottom:50px;border-bottom:1px solid rgba(247,249,252,0.12);}
.brand-footer{color:var(--crema);margin-bottom:14px;}
.brand-footer .brand-mark{color:#FCD34D;}
.footer-desc{font-size:0.88rem;color:rgba(247,249,252,0.65);max-width:34ch;}
.footer-heading{
  font-family:'IBM Plex Mono',monospace;font-size:0.76rem;
  text-transform:uppercase;letter-spacing:0.1em;
  color:#FCD34D;margin-bottom:16px;font-weight:600;
}
.footer-list li{margin-bottom:10px;font-size:0.9rem;}
.footer-list a:hover{color:#FCD34D;}
.footer-resp{font-size:0.88rem;color:rgba(247,249,252,0.7);line-height:1.7;}
.footer-bottom{padding:22px 0 26px;font-size:0.8rem;color:rgba(247,249,252,0.55);}
.footer-bottom p{margin:0;}

/* ---------- LEGAL PAGES ---------- */
.legal-hero{
  background:var(--azul-profundo);color:var(--crema);
  padding:120px 0 60px;
}
.legal-hero .eyebrow{color:#FCD34D;}
.legal-hero .eyebrow::before{background:#FCD34D;}
.legal-hero h1{color:var(--crema);font-size:clamp(1.9rem,3.6vw,2.6rem);margin-top:14px;}
.legal-body{padding:60px 0 100px;}
.legal-content{max-width:760px;margin:0 auto;}
.legal-content h2{font-size:1.35rem;margin:42px 0 14px;}
.legal-content h2:first-child{margin-top:0;}
.legal-content p,.legal-content li{color:var(--tinta-suave);font-size:0.98rem;margin-bottom:12px;}
.legal-content ul{padding-left:22px;list-style:disc;}
.legal-content table{width:100%;border-collapse:collapse;margin:18px 0;font-size:0.92rem;}
.legal-content th,.legal-content td{text-align:left;padding:10px 12px;border-bottom:1px solid var(--linea);color:var(--tinta-suave);}
.legal-content th{color:var(--azul-profundo);font-family:'IBM Plex Mono',monospace;font-size:0.78rem;text-transform:uppercase;}
.legal-update{
  font-family:'IBM Plex Mono',monospace;font-size:0.8rem;
  color:var(--azul);margin-bottom:30px;display:block;
}
.legal-note{
  background:var(--crema-2);border-left:3px solid var(--ambar);
  padding:16px 20px;border-radius:8px;font-size:0.92rem;color:var(--tinta-suave);
}

/* ---------- RESPONSIVE ---------- */
@media (max-width:980px){
  .hero-inner{grid-template-columns:1fr;}
  .hero-art{height:260px;order:-1;}
  .factura-mock{grid-template-columns:1fr;}
  .factura-visual{position:static;}
  .glosario-grid{grid-template-columns:repeat(2,1fr);}
  .consejo-grid{grid-template-columns:1fr 1fr;}
  .footer-grid{grid-template-columns:1fr 1fr;}
}
@media (max-width:680px){
  .nav-toggle{display:flex;}
  .nav-list{
    position:absolute;top:74px;left:0;right:0;
    background:var(--crema);flex-direction:column;gap:0;
    border-bottom:1px solid var(--linea);
    max-height:0;overflow:hidden;transition:max-height .25s ease;
  }
  .nav-list.is-open{max-height:320px;}
  .nav-list li{border-top:1px solid var(--linea);}
  .nav-list a{display:block;padding:16px 28px;color:var(--tinta);}
  .glosario-grid,.consejo-grid,.footer-grid{grid-template-columns:1fr;}
  .hero{padding-top:84px;}
  .hero-stats{gap:20px;}
}