/* =========================================================
   rejillaelectroforjada.com — hoja de estilos
   Paleta: azul fuerte, celeste y gris para énfasis;
   fondos alternados en blanco, gris claro y negro.
   ========================================================= */

:root {
  --azul: #0a3a8c;
  --azul-osc: #072a66;
  --celeste: #34b5e8;
  --celeste-suave: #d6f0fb;
  --gris: #6b7682;
  --gris-medio: #c3cad1;
  --gris-claro: #eceff2;
  --blanco: #ffffff;
  --negro: #000000;
  --texto: #1b1f24;

  --font: "Archivo", "Helvetica Neue", Arial, sans-serif;
  --wrap: 72rem;
  --radio: 4px;
  --header-h: 4.25rem;

  box-sizing: border-box;
}

*, *::before, *::after { box-sizing: inherit; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 1rem);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 1.0625rem;
  line-height: 1.65;
  color: var(--texto);
  background: var(--blanco);
}

img { max-width: 100%; height: auto; }

a { color: var(--azul); text-underline-offset: 3px; }
a:hover { color: var(--celeste); }

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

h1, h2, h3 {
  line-height: 1.1;
  margin: 0 0 1rem;
  font-stretch: 112%;
  letter-spacing: -0.01em;
}
h2 { font-size: clamp(1.75rem, 1.2rem + 2.2vw, 2.75rem); font-weight: 800; color: var(--azul); }
h3 { font-size: 1.25rem; font-weight: 700; }
p { margin: 0 0 1rem; max-width: 68ch; }

.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: clamp(1.15rem, 4vw, 2rem);
}

.skip {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--celeste);
  color: var(--negro);
  padding: .6rem 1rem;
  z-index: 100;
}
.skip:focus { left: 1rem; top: 1rem; }

/* ---------- Botones ---------- */
.btn {
  display: inline-block;
  padding: .85rem 1.5rem;
  font-weight: 700;
  font-stretch: 108%;
  text-decoration: none;
  border-radius: var(--radio);
  border: 2px solid transparent;
  transition: background-color .2s, color .2s, border-color .2s;
}
.btn-primary { background: var(--celeste); color: var(--negro); }
.btn-primary:hover { background: var(--blanco); color: var(--azul); }
.btn-ghost { border-color: var(--blanco); color: var(--blanco); }
.btn-ghost:hover { background: var(--blanco); color: var(--azul); }
.btn-dark { background: var(--azul); color: var(--blanco); }
.btn-dark:hover { background: var(--negro); color: var(--blanco); }
.btn-light { background: var(--blanco); color: var(--azul); }
.btn-light:hover { background: var(--negro); color: var(--blanco); }

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--blanco);
  border-bottom: 3px solid var(--azul);
  padding-top: env(safe-area-inset-top, 0px);
}
.header-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: var(--header-h);
  gap: 1rem;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: .65rem;
  text-decoration: none;
  color: var(--texto);
  margin: 0;
}
.logo-mark {
  width: 1.9rem;
  height: 1.9rem;
  flex: none;
  border: 3px solid var(--azul);
  background:
    repeating-linear-gradient(90deg, var(--azul) 0 3px, transparent 3px 7px),
    linear-gradient(0deg, transparent 45%, var(--celeste) 45% 58%, transparent 58%);
}
.logo-text { display: flex; flex-direction: column; line-height: 1; }
.logo-a {
  font-size: .78rem;
  font-weight: 600;
  font-stretch: 125%;
  color: var(--gris);
  letter-spacing: .02em;
}
.logo-b {
  font-size: 1.2rem;
  font-weight: 800;
  font-stretch: 85%;
  color: var(--azul);
}

.nav-toggle { position: absolute; opacity: 0; width: 1px; height: 1px; }
.nav-burger { display: none; }

.main-nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  align-items: center;
  gap: .25rem;
}
.main-nav a {
  display: block;
  padding: .5rem .7rem;
  font-size: .95rem;
  font-weight: 600;
  color: var(--texto);
  text-decoration: none;
  border-radius: var(--radio);
}
.main-nav a:hover { color: var(--azul); background: var(--gris-claro); }
.main-nav .nav-cta {
  background: var(--azul);
  color: var(--blanco);
  margin-left: .5rem;
}
.main-nav .nav-cta:hover { background: var(--celeste); color: var(--negro); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  background-color: var(--negro);
  background-image:
    linear-gradient(90deg, rgba(0,0,0,.92) 0%, rgba(0,0,0,.7) 45%, rgba(0,0,0,.15) 100%),
    url("../img/hero-rejilla-electroforjada.svg");
  background-size: cover;
  background-position: center;
  color: var(--blanco);
  padding-block: clamp(5rem, 14vw, 9.5rem);
}
.hero-inner { max-width: var(--wrap); }
.hero h1 {
  font-size: clamp(2.3rem, 1.3rem + 4.6vw, 4.6rem);
  font-weight: 800;
  font-stretch: 78%;
  line-height: 1;
  max-width: 15ch;
  margin-bottom: 1.5rem;
}
.hero-sub {
  font-size: clamp(1.05rem, 1rem + .4vw, 1.25rem);
  color: var(--gris-medio);
  max-width: 54ch;
  margin-bottom: 2rem;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: .85rem; }

/* ---------- Secciones ---------- */
.section { padding-block: clamp(3.5rem, 8vw, 6rem); }
.lead { font-size: 1.15rem; color: var(--gris); margin-bottom: 2rem; }

.section-link, .table-note, .decoder-note, .faq-more { margin-top: 1.75rem; }
.section-link a { font-weight: 700; }

/* Qué es */
.intro { background: var(--blanco); }
.intro-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
  gap: clamp(2rem, 5vw, 4rem);
  align-items: start;
}
.process {
  background: var(--gris-claro);
  border-left: 6px solid var(--celeste);
  padding: 1.75rem;
}
.process h3 { color: var(--azul); }
.process ol { margin: 0; padding-left: 1.25rem; }
.process li { margin-bottom: .75rem; }
.process li::marker { font-weight: 800; color: var(--azul); }

/* Nomenclatura (elemento protagonista) */
.decoder { background: var(--negro); color: var(--blanco); }
.decoder h2 { color: var(--blanco); }
.decoder .lead { color: var(--gris-medio); }
.code {
  display: grid;
  grid-template-columns: 1fr auto 1fr auto 1fr;
  align-items: start;
  gap: clamp(.5rem, 2vw, 1.5rem);
  border-top: 2px solid var(--gris);
  border-bottom: 2px solid var(--gris);
  padding-block: 2rem;
}
.code-big {
  display: block;
  font-size: clamp(4.5rem, 2rem + 11vw, 10rem);
  font-weight: 800;
  font-stretch: 125%;
  line-height: .9;
  color: var(--celeste);
  margin-bottom: 1rem;
}
.code-part:nth-of-type(2) .code-big { color: var(--blanco); }
.code-dash {
  font-size: clamp(3rem, 1.5rem + 7vw, 6.5rem);
  font-weight: 300;
  color: var(--gris);
  line-height: 1;
}
.code-part p { color: var(--gris-medio); font-size: .98rem; }
.decoder a { color: var(--celeste); }
.decoder a:hover { color: var(--blanco); }

/* Tablas */
.specs { background: var(--blanco); }
.acabados { background: var(--gris-claro); }
.table-scroll { overflow-x: auto; -webkit-overflow-scrolling: touch; }
table {
  width: 100%;
  min-width: 36rem;
  border-collapse: collapse;
  background: var(--blanco);
  font-size: 1rem;
}
caption {
  text-align: left;
  font-weight: 700;
  color: var(--gris);
  padding-bottom: .75rem;
}
thead th {
  background: var(--azul);
  color: var(--blanco);
  text-align: left;
  font-stretch: 110%;
}
th, td {
  padding: .85rem 1rem;
  border-bottom: 1px solid var(--gris-medio);
  vertical-align: top;
}
tbody th { text-align: left; font-weight: 700; color: var(--azul); width: 32%; }
tbody tr:nth-child(even) { background: #f7f9fa; }

/* Tipos */
.tipos { background: var(--gris-claro); }
.type-list {
  margin: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(17rem, 1fr));
  gap: 0;
  border-top: 3px solid var(--azul);
}
.type-list > div {
  padding: 1.5rem 1.5rem 1.5rem 0;
  border-bottom: 1px solid var(--gris-medio);
}
.type-list dt {
  font-size: 1.2rem;
  font-weight: 800;
  font-stretch: 110%;
  color: var(--azul);
  margin-bottom: .4rem;
}
.type-list dd { margin: 0; }

/* Materiales */
.materiales { background: var(--blanco); }
.mat-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(1rem, 3vw, 2rem);
}
.mat {
  padding: 1.75rem;
  border-top: 10px solid;
  background: var(--gris-claro);
}
.mat-acero { border-top-color: #3d4650; }
.mat-inox { border-top-color: var(--celeste); }
.mat-alu { border-top-color: var(--gris-medio); }
.mat h3 { color: var(--azul); }
.mat ul { margin: 0; padding-left: 1.1rem; color: var(--gris); }
.mat li { margin-bottom: .35rem; }

/* Aplicaciones */
.aplicaciones { background: var(--azul); color: var(--blanco); }
.aplicaciones h2 { color: var(--blanco); }
.apl-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.4fr);
  gap: clamp(2rem, 5vw, 4rem);
}
.apl-list {
  list-style: none;
  margin: 0;
  padding: 0;
  columns: 2;
  column-gap: 2rem;
}
.apl-list li {
  break-inside: avoid;
  padding: .65rem 0 .65rem 1.25rem;
  border-bottom: 1px solid rgba(255,255,255,.2);
  position: relative;
}
.apl-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 1.15rem;
  width: .55rem;
  height: .55rem;
  background: var(--celeste);
}

/* Escalones */
.escalones { background: var(--negro); color: var(--blanco); }
.escalones h2 { color: var(--blanco); }
.esc-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr);
  gap: clamp(2rem, 5vw, 4rem);
  align-items: center;
}
.esc-text > p { color: var(--gris-medio); }
.esc-list { list-style: none; padding: 0; margin: 0 0 2rem; }
.esc-list li {
  padding: .85rem 0 .85rem 1rem;
  border-left: 3px solid var(--celeste);
  margin-bottom: .6rem;
  color: var(--gris-medio);
}
.esc-list strong { color: var(--blanco); }

.step-figure { margin: 0; perspective: 900px; }
.step {
  position: relative;
  aspect-ratio: 3 / 1.4;
  transform: rotateX(52deg) rotateZ(-8deg);
  margin-inline: auto;
  width: 90%;
}
.step-grate {
  position: absolute;
  inset: 0 6% 0 6%;
  background:
    repeating-linear-gradient(0deg, transparent 0 22%, #9aa6b2 22% 26%),
    repeating-linear-gradient(90deg, #4a5560 0 4px, #000 4px 13px);
}
.step-nose {
  position: absolute;
  left: 6%;
  right: 6%;
  bottom: -9%;
  height: 16%;
  z-index: 2;
  background:
    repeating-linear-gradient(45deg, #b8c3cd 0 3px, #7d8893 3px 7px);
  border-top: 2px solid var(--celeste);
}
.step-plate {
  position: absolute;
  top: -4%;
  bottom: -9%;
  width: 6%;
  background: var(--gris);
  box-shadow: inset 0 0 0 2px #3d4650;
}
.step-plate-l { left: 0; }
.step-plate-r { right: 0; }

/* Corte a medida */
.corte { background: var(--gris-claro); }
.corte-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(1.5rem, 4vw, 3rem);
}
.corte-grid > div {
  background: var(--blanco);
  padding: 2rem;
  border-left: 6px solid var(--azul);
}
.corte-grid h3 { color: var(--azul); }
.corte-grid ul { padding-left: 1.1rem; margin: 0 0 1.5rem; }
.corte-grid li { margin-bottom: .4rem; }

/* FAQ */
.faq { background: var(--blanco); }
.faq-wrap { max-width: 52rem; }
details {
  border-bottom: 1px solid var(--gris-medio);
}
details:first-of-type { border-top: 3px solid var(--azul); }
summary {
  cursor: pointer;
  list-style: none;
  padding: 1.2rem 2.5rem 1.2rem 0;
  font-weight: 700;
  font-size: 1.1rem;
  position: relative;
}
summary::-webkit-details-marker { display: none; }
summary::after {
  content: "+";
  position: absolute;
  right: .25rem;
  top: 50%;
  transform: translateY(-50%);
  font-size: 1.6rem;
  font-weight: 400;
  color: var(--azul);
}
details[open] summary { color: var(--azul); }
details[open] summary::after { content: "−"; }
details p { padding-bottom: 1.2rem; color: #3a424a; }

/* CTA */
.cta {
  background:
    linear-gradient(135deg, var(--azul) 0%, var(--azul-osc) 100%);
  color: var(--blanco);
  padding-block: clamp(3.5rem, 8vw, 5.5rem);
  border-top: 6px solid var(--celeste);
}
.cta-inner { text-align: center; }
.cta h2 { color: var(--blanco); max-width: 22ch; margin-inline: auto; }
.cta p { margin-inline: auto; color: var(--celeste-suave); margin-bottom: 2rem; }

/* Footer */
.site-footer {
  background: var(--negro);
  color: var(--gris-medio);
  padding-top: 3.5rem;
  padding-bottom: calc(1.5rem + env(safe-area-inset-bottom, 0px));
  font-size: .95rem;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: 2rem;
}
.site-footer .logo-b { color: var(--blanco); }
.site-footer .logo-mark { border-color: var(--celeste); background:
    repeating-linear-gradient(90deg, var(--celeste) 0 3px, transparent 3px 7px); }
.footer-about { margin-top: 1rem; max-width: 36ch; }
.footer-h {
  font-size: 1rem;
  color: var(--blanco);
  margin-bottom: .75rem;
  font-stretch: 110%;
}
.site-footer ul { list-style: none; margin: 0; padding: 0; }
.site-footer li { margin-bottom: .45rem; }
.site-footer a { color: var(--gris-medio); text-decoration: none; }
.site-footer a:hover { color: var(--celeste); text-decoration: underline; }
.footer-bottom {
  border-top: 1px solid #2a2f35;
  margin-top: 2.5rem;
  padding-top: 1.5rem;
}
.footer-bottom p { margin: 0; font-size: .85rem; color: var(--gris); max-width: none; }

/* =========================================================
   Responsive
   ========================================================= */
@media (max-width: 1060px) {
  .nav-burger {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 2.75rem;
    height: 2.75rem;
    cursor: pointer;
    border: 2px solid var(--azul);
    border-radius: var(--radio);
  }
  .nav-burger span,
  .nav-burger span::before,
  .nav-burger span::after {
    display: block;
    width: 1.3rem;
    height: 2px;
    background: var(--azul);
    position: relative;
    transition: transform .2s;
  }
  .nav-burger span::before,
  .nav-burger span::after { content: ""; position: absolute; left: 0; }
  .nav-burger span::before { top: -6px; }
  .nav-burger span::after { top: 6px; }

  .nav-toggle:focus-visible + .nav-burger { outline: 3px solid var(--celeste); outline-offset: 3px; }
  .nav-toggle:checked + .nav-burger span { background: transparent; }
  .nav-toggle:checked + .nav-burger span::before { transform: translateY(6px) rotate(45deg); }
  .nav-toggle:checked + .nav-burger span::after { transform: translateY(-6px) rotate(-45deg); }

  .main-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    background: var(--blanco);
    border-bottom: 3px solid var(--azul);
    display: none;
    max-height: calc(100vh - var(--header-h));
    overflow-y: auto;
  }
  .nav-toggle:checked ~ .main-nav { display: block; }
  .main-nav ul {
    flex-direction: column;
    align-items: stretch;
    padding: .5rem clamp(1.15rem, 4vw, 2rem) 1.25rem;
    gap: 0;
  }
  .main-nav a { padding: .9rem .25rem; border-bottom: 1px solid var(--gris-claro); border-radius: 0; }
  .main-nav .nav-cta { margin: 1rem 0 0; text-align: center; border-radius: var(--radio); border: 0; }
}

@media (max-width: 860px) {
  .intro-grid,
  .apl-grid,
  .esc-grid,
  .corte-grid { grid-template-columns: 1fr; }
  .mat-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-grid > div:first-child { grid-column: 1 / -1; }
  .step-figure { max-width: 26rem; margin-inline: auto; }
}

@media (max-width: 620px) {
  .code {
    grid-template-columns: 1fr;
    gap: 0;
  }
  .code-dash { display: none; }
  .code-part {
    display: grid;
    grid-template-columns: 6.5rem 1fr;
    gap: 1rem;
    align-items: center;
    padding-block: 1rem;
    border-bottom: 1px solid #2a2f35;
  }
  .code-part:last-child { border-bottom: 0; }
  .code-big { font-size: 4.5rem; margin: 0; }
  .code-part p { margin: 0; }
  .apl-list { columns: 1; }
  .hero {
    background-image:
      linear-gradient(180deg, rgba(0,0,0,.78) 0%, rgba(0,0,0,.88) 100%),
      url("../img/hero-rejilla-electroforjada.svg");
  }
  .hero-actions .btn { flex: 1 1 100%; text-align: center; }
  .footer-grid { grid-template-columns: 1fr; }
  .corte-grid > div, .process, .mat { padding: 1.4rem; }
}

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

@media print {
  .site-header, .hero-actions, .cta, .nav-burger { display: none; }
  .hero, .decoder, .escalones, .aplicaciones { background: none; color: #000; }
}