/* =========================================================
   RejillaIndustrial.com — Hoja de estilos
   Paleta: negro, gris, blanco + celeste como énfasis
   ========================================================= */

:root {
  --celeste: #3DB7E4;
  --celeste-claro: #8FD6F1;
  --negro: #000000;
  --grafito: #1B1E21;
  --gris-medio: #5F666D;
  --gris-claro: #E7E9EB;
  --blanco: #FFFFFF;

  --font-display: "Barlow Condensed", "Arial Narrow", "Roboto Condensed", sans-serif;
  --font-body: "Barlow", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;

  --container: 1180px;
  --radius: 4px;
  --header-h: 72px;
}

/* ---------- Reset básico ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: var(--header-h); -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 1.0625rem;
  line-height: 1.65;
  color: var(--grafito);
  background: var(--blanco);
  -webkit-font-smoothing: antialiased;
}
img, svg { display: block; max-width: 100%; }
h1, h2, h3 { font-family: var(--font-display); line-height: 1.08; margin: 0 0 .5em; color: inherit; }
h2 { font-size: clamp(2rem, 4.2vw, 3rem); font-weight: 700; letter-spacing: -.01em; }
h3 { font-size: 1.45rem; font-weight: 700; }
p { margin: 0 0 1em; }
ul, ol, dl { margin: 0; padding: 0; }
a { color: inherit; }

:focus-visible { outline: 3px solid var(--celeste); outline-offset: 3px; }

.container { width: 100%; max-width: var(--container); margin: 0 auto; padding: 0 1.25rem; }

.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}
.skip-link {
  position: absolute; left: 1rem; top: -100px; z-index: 200;
  background: var(--celeste); color: var(--negro); padding: .6rem 1rem; font-weight: 600;
}
.skip-link:focus { top: 1rem; }

/* ---------- Botones ---------- */
.btn {
  display: inline-block;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.2rem;
  letter-spacing: .01em;
  text-decoration: none;
  padding: .85rem 1.6rem;
  border-radius: var(--radius);
  border: 2px solid transparent;
  transition: background-color .2s, color .2s, border-color .2s;
  text-align: center;
}
.btn-primary { background: var(--celeste); color: var(--negro); }
.btn-primary:hover { background: var(--blanco); }
.btn-ghost { border-color: var(--blanco); color: var(--blanco); }
.btn-ghost:hover { background: var(--blanco); color: var(--negro); }
.btn-dark { background: var(--negro); color: var(--blanco); }
.btn-dark:hover { background: var(--grafito); color: var(--celeste-claro); }

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: var(--negro);
  color: var(--blanco);
  border-bottom: 3px solid var(--celeste);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; min-height: var(--header-h); }

.brand { display: inline-flex; align-items: center; gap: .65rem; text-decoration: none; color: var(--blanco); }
.brand-mark { width: 38px; height: 38px; color: var(--blanco); }
.brand-name { font-family: var(--font-display); font-size: 1.55rem; font-weight: 600; letter-spacing: .01em; }
.brand-name strong { font-weight: 800; color: var(--celeste); margin-left: .1em; }

.main-nav ul { list-style: none; display: flex; align-items: center; gap: 1.6rem; }
.main-nav a { text-decoration: none; font-weight: 500; font-size: 1rem; padding: .4rem 0; border-bottom: 2px solid transparent; }
.main-nav a:hover { border-bottom-color: var(--celeste); }
.main-nav .nav-cta {
  background: var(--celeste); color: var(--negro); padding: .55rem 1.1rem;
  border-radius: var(--radius); border: 0; font-weight: 600;
}
.main-nav .nav-cta:hover { background: var(--blanco); }

.nav-toggle { position: absolute; opacity: 0; pointer-events: none; }
.nav-toggle-label { display: none; }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  color: var(--blanco);
  min-height: min(88vh, 760px);
  display: flex;
  align-items: flex-end;
  padding: 7rem 0 5rem;
  background-color: var(--negro);
  /* Capas: trama de rejilla + degradado de lectura + fotografía */
  background-image:
    repeating-linear-gradient(90deg, rgba(255,255,255,.07) 0 3px, transparent 3px 36px),
    repeating-linear-gradient(0deg, rgba(61,183,228,.10) 0 2px, transparent 2px 110px),
    linear-gradient(180deg, rgba(0,0,0,.35) 0%, rgba(0,0,0,.85) 75%, #000 100%),
    url("../img/rejilla-industrial-hero.webp");
  background-size: auto, auto, cover, cover;
  background-position: center, center, center, center;
  background-repeat: repeat, repeat, no-repeat, no-repeat;
}
.hero-inner { max-width: var(--container); }
.hero h1 {
  font-size: clamp(2.8rem, 8vw, 6.2rem);
  font-weight: 800;
  line-height: .95;
  letter-spacing: -.015em;
  max-width: 14ch;
  margin-bottom: .35em;
  padding-left: 1.25rem;
  border-left: 8px solid var(--celeste);
}
.hero-sub { font-size: clamp(1.1rem, 2vw, 1.3rem); max-width: 58ch; color: #D6DADD; margin-bottom: 2rem; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 1rem; }

/* ---------- Secciones ---------- */
.section { padding: clamp(4rem, 9vw, 7rem) 0; }
.section-light { background: var(--blanco); }
.section-gray { background: var(--gris-claro); }
.section-dark { background: var(--grafito); color: var(--blanco); }

.lead { font-size: 1.2rem; max-width: 62ch; color: var(--gris-medio); margin-bottom: 3rem; }
.section-dark .lead { color: #C3C8CC; }

.prose a, .steps a, .faq a {
  color: var(--grafito);
  text-decoration: underline;
  text-decoration-color: var(--celeste);
  text-decoration-thickness: 2px;
  text-underline-offset: 3px;
  font-weight: 600;
}
.prose a:hover, .steps a:hover, .faq a:hover { color: #0F7FA8; }

.section-link { margin: 3rem 0 0; }
.section-link a {
  font-family: var(--font-display); font-weight: 700; font-size: 1.3rem;
  text-decoration: none; border-bottom: 3px solid var(--celeste); padding-bottom: .15rem;
}
.section-link a:hover { color: var(--celeste); }
.section-dark .section-link a:hover { color: var(--celeste-claro); }

/* Diseño a dos columnas */
.split { display: grid; grid-template-columns: 5fr 7fr; gap: clamp(2rem, 6vw, 5rem); align-items: start; }
.split-head h2 { border-top: 6px solid var(--celeste); padding-top: 1rem; }
.split-head p { color: var(--gris-medio); font-size: 1.1rem; }
.prose p { max-width: 64ch; }

/* ---------- Beneficios ---------- */
.benefits {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid rgba(255,255,255,.18);
}
.benefit {
  padding: 2rem 1.75rem 2rem 0;
  border-bottom: 1px solid rgba(255,255,255,.18);
}
.benefit + .benefit { padding-left: 1.75rem; border-left: 1px solid rgba(255,255,255,.18); }
.benefit:nth-child(3n+1) { padding-left: 0; border-left: 0; }
.benefit h3 { color: var(--celeste); }
.benefit p { color: #C3C8CC; margin: 0; }

/* ---------- Aplicaciones ---------- */
.apps { display: grid; grid-template-columns: repeat(2, 1fr); gap: 0 3rem; }
.app { padding: 1.5rem 0; border-top: 2px solid var(--negro); }
.app dt { font-family: var(--font-display); font-weight: 700; font-size: 1.55rem; margin-bottom: .25rem; }
.app dd { margin: 0; color: var(--gris-medio); }

/* ---------- Pasos (secuencia real) ---------- */
.steps { list-style: none; counter-reset: paso; }
.steps li {
  counter-increment: paso;
  position: relative;
  padding: 0 0 2rem 4.5rem;
  margin-bottom: 2rem;
  border-bottom: 1px solid var(--gris-claro);
}
.steps li:last-child { margin-bottom: 0; border-bottom: 0; }
.steps li::before {
  content: counter(paso);
  position: absolute; left: 0; top: -.2rem;
  width: 3rem; height: 3rem;
  display: grid; place-items: center;
  font-family: var(--font-display); font-weight: 800; font-size: 1.6rem;
  background: var(--negro); color: var(--celeste);
  border-radius: var(--radius);
}
.steps p { margin: 0; color: var(--gris-medio); }

/* ---------- FAQ ---------- */
.faq-wrap { max-width: 860px; }
.faq { border-top: 2px solid var(--negro); }
.faq details { border-bottom: 1px solid #C9CDD1; }
.faq summary {
  list-style: none;
  cursor: pointer;
  position: relative;
  padding: 1.35rem 3rem 1.35rem 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.4rem;
  line-height: 1.2;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "";
  position: absolute; right: .5rem; top: 50%;
  width: 14px; height: 14px;
  border-right: 3px solid var(--celeste);
  border-bottom: 3px solid var(--celeste);
  transform: translateY(-70%) rotate(45deg);
  transition: transform .2s;
}
.faq details[open] summary::after { transform: translateY(-30%) rotate(-135deg); }
.faq summary:hover { color: #0F7FA8; }
.faq details p { padding: 0 3rem 1.5rem 0; margin: 0; color: var(--gris-medio); max-width: 70ch; }

/* ---------- CTA ---------- */
.cta {
  background-color: var(--celeste);
  background-image: repeating-linear-gradient(90deg, rgba(0,0,0,.06) 0 3px, transparent 3px 36px);
  color: var(--negro);
  padding: clamp(4rem, 8vw, 6rem) 0;
}
.cta-inner { max-width: 820px; text-align: center; }
.cta h2 { font-size: clamp(2.2rem, 5vw, 3.6rem); font-weight: 800; }
.cta p { font-size: 1.2rem; max-width: 56ch; margin: 0 auto 2rem; }

/* ---------- Footer ---------- */
.site-footer { background: var(--negro); color: #BFC4C8; padding-top: 4rem; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1.3fr; gap: 3rem; padding-bottom: 3rem; }
.footer-brand p { margin-top: 1rem; max-width: 38ch; }
.footer-title { font-size: 1.3rem; color: var(--blanco); margin-bottom: 1rem; }
.footer-nav ul { list-style: none; }
.footer-nav li { margin-bottom: .5rem; }
.footer-nav a { text-decoration: none; }
.footer-nav a:hover { color: var(--celeste); }
.footer-link { color: var(--celeste); font-weight: 600; text-underline-offset: 3px; }
.footer-link:hover { color: var(--blanco); }
.footer-bottom { border-top: 1px solid #2B2F33; padding-top: 1.5rem; padding-bottom: 1.5rem; font-size: .9rem; }
.footer-bottom p { margin: 0; }

/* =========================================================
   Responsivo
   ========================================================= */
@media (max-width: 960px) {
  .benefits { grid-template-columns: repeat(2, 1fr); }
  .benefit, .benefit + .benefit { padding: 2rem 1.5rem 2rem 0; border-left: 0; }
  .benefit:nth-child(2n) { padding-left: 1.5rem; padding-right: 0; border-left: 1px solid rgba(255,255,255,.18); }
  .split { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 860px) {
  .nav-toggle-label {
    display: grid; place-items: center;
    width: 46px; height: 46px; cursor: pointer;
  }
  .burger, .burger::before, .burger::after {
    display: block; width: 26px; height: 3px; background: var(--blanco);
    position: relative; transition: transform .2s, background-color .2s;
  }
  .burger::before, .burger::after { content: ""; position: absolute; left: 0; }
  .burger::before { top: -8px; }
  .burger::after { top: 8px; }

  .main-nav {
    position: absolute; left: 0; right: 0; top: 100%;
    background: var(--negro);
    border-bottom: 3px solid var(--celeste);
    max-height: 0; overflow: hidden;
    transition: max-height .3s ease;
  }
  .main-nav ul { flex-direction: column; align-items: stretch; gap: 0; padding: .5rem 1.25rem 1.25rem; }
  .main-nav a { display: block; padding: .9rem 0; border-bottom: 1px solid #2B2F33; }
  .main-nav .nav-cta { margin-top: 1rem; text-align: center; padding: .9rem; }

  .nav-toggle:checked ~ .main-nav { max-height: 480px; }
  .nav-toggle:checked + .nav-toggle-label .burger { background: transparent; }
  .nav-toggle:checked + .nav-toggle-label .burger::before { transform: translateY(8px) rotate(45deg); }
  .nav-toggle:checked + .nav-toggle-label .burger::after { transform: translateY(-8px) rotate(-45deg); }
  .nav-toggle:focus-visible + .nav-toggle-label { outline: 3px solid var(--celeste); }
  .header-inner { position: relative; }
}

@media (max-width: 600px) {
  body { font-size: 1rem; }
  .hero { min-height: 82vh; padding: 5rem 0 3.5rem; }
  .hero h1 { border-left-width: 6px; padding-left: 1rem; }
  .hero-actions .btn { width: 100%; }
  .benefits { grid-template-columns: 1fr; }
  .benefit, .benefit + .benefit, .benefit:nth-child(2n) { padding: 1.75rem 0; border-left: 0; }
  .apps { grid-template-columns: 1fr; }
  .steps li { padding-left: 4rem; }
  .faq summary { font-size: 1.25rem; padding-right: 2.5rem; }
  .faq details p { padding-right: 0; }
  .footer-grid { grid-template-columns: 1fr; gap: 2rem; }
  .cta .btn { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; }
}