:root {
  --tinta: #16181a;
  --texto: #3a3f44;
  --suave: #6b7177;
  --fondo: #f7f5f1;
  --papel: #ffffff;
  --linea: #e3dfd7;
  --madera: #b8875a;
  --madera-osc: #8a5f38;
  --ancho: 1120px;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--fondo);
  color: var(--texto);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 17px;
  line-height: 1.6;
}
img { max-width: 100%; display: block; }
a { color: var(--madera-osc); }

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

/* Cabecera */
.cabecera {
  position: sticky; top: 0; z-index: 10;
  background: rgba(247, 245, 241, 0.94);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--linea);
}
.cabecera .contenedor { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.marca {
  font-family: Impact, Haettenschweiler, "Arial Narrow Bold", "Franklin Gothic Bold", sans-serif;
  font-size: 30px; letter-spacing: 0.5px; color: var(--tinta); text-decoration: none; line-height: 1;
}
.nav a { color: var(--tinta); text-decoration: none; font-size: 15px; margin-left: 24px; }
.nav a:hover { color: var(--madera-osc); }
.nav .btn-nav { border: 1px solid var(--tinta); padding: 7px 14px; border-radius: 4px; }
@media (max-width: 640px) { .nav a:not(.btn-nav) { display: none; } }

/* Portada */
.portada { position: relative; min-height: 78vh; display: flex; align-items: flex-end; color: #fff; overflow: hidden; }
.portada img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; filter: brightness(0.62) saturate(0.9); }
.portada .contenedor { position: relative; padding-top: 120px; padding-bottom: 64px; width: 100%; }
.etiqueta { text-transform: uppercase; letter-spacing: 2px; font-size: 13px; opacity: 0.85; margin: 0 0 12px; }
.portada h1 { font-size: clamp(34px, 5.4vw, 60px); line-height: 1.08; margin: 0 0 18px; max-width: 16em; color: #fff; font-weight: 700; }
.portada p.lead { font-size: clamp(17px, 2vw, 20px); max-width: 34em; margin: 0 0 28px; opacity: 0.95; }
.boton { display: inline-block; background: var(--madera); color: #fff; text-decoration: none; padding: 13px 22px; border-radius: 4px; font-weight: 600; }
.boton:hover { background: var(--madera-osc); }

/* Secciones */
section { padding: 88px 0; }
section.blanco { background: var(--papel); border-top: 1px solid var(--linea); border-bottom: 1px solid var(--linea); }
h2 { font-size: clamp(26px, 3.4vw, 36px); line-height: 1.15; color: var(--tinta); margin: 0 0 16px; }
.intro { max-width: 40em; font-size: 18px; margin: 0 0 48px; }

.tres { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; }
@media (max-width: 860px) { .tres { grid-template-columns: 1fr; } }
.pilar h3 { font-size: 19px; color: var(--tinta); margin: 0 0 8px; }
.pilar p { margin: 0; }
.pilar .num { display: block; font-size: 13px; letter-spacing: 2px; color: var(--madera-osc); margin-bottom: 10px; font-weight: 600; }

/* Plataforma */
.plataforma { display: grid; grid-template-columns: 1.1fr 1fr; gap: 56px; align-items: center; }
@media (max-width: 860px) { .plataforma { grid-template-columns: 1fr; gap: 32px; } }
.marcas { list-style: none; padding: 0; margin: 24px 0 0; display: flex; flex-wrap: wrap; gap: 10px; }
.marcas li { border: 1px solid var(--linea); background: var(--fondo); padding: 8px 14px; border-radius: 999px; font-size: 15px; color: var(--tinta); }
.plataforma figure { margin: 0; }
.plataforma figure img { border-radius: 6px; width: 100%; max-height: 480px; object-fit: cover; }

/* Galería */
.galeria { display: grid; grid-template-columns: repeat(6, 1fr); gap: 14px; }
.galeria figure { margin: 0; position: relative; overflow: hidden; border-radius: 6px; background: #ddd; }
.galeria img { width: 100%; height: 100%; object-fit: cover; aspect-ratio: 4 / 3; }
.galeria figcaption { position: absolute; left: 0; right: 0; bottom: 0; padding: 22px 14px 10px; font-size: 14px; color: #fff; background: linear-gradient(transparent, rgba(0,0,0,0.65)); }
.g-a { grid-column: span 4; } .g-b { grid-column: span 2; }
.g-c { grid-column: span 2; } .g-d { grid-column: span 2; } .g-e { grid-column: span 2; }
.g-h { grid-column: span 3; } .g-i { grid-column: span 3; }
.g-c img { object-position: center 35%; }
.g-f { grid-column: span 6; }
.g-w { grid-column: span 6; }
.g-w img { aspect-ratio: 20 / 9; }
.g-f img { aspect-ratio: 21 / 8; }
.g-b img { aspect-ratio: auto; }
@media (max-width: 760px) {
  .galeria { grid-template-columns: 1fr 1fr; }
  .g-a, .g-f, .g-w { grid-column: span 2; }
  .g-f img { aspect-ratio: 4 / 3; }
  .g-b, .g-c, .g-d, .g-e, .g-h, .g-i { grid-column: span 1; }
  .g-b img { aspect-ratio: 4 / 3; }
}

/* Hitos */
.hitos { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 0; border-top: 2px solid var(--tinta); }
.hitos li { padding: 20px 24px 0 0; position: relative; }
.hitos li::before { content: ""; position: absolute; top: -8px; left: 0; width: 14px; height: 14px; border-radius: 50%; background: var(--tinta); }
.hitos li.futuro::before { background: var(--fondo); border: 2px solid var(--tinta); }
.hitos .cuando { font-weight: 700; color: var(--tinta); display: block; margin-bottom: 4px; }
@media (max-width: 760px) {
  .hitos { grid-template-columns: 1fr; border-top: 0; border-left: 2px solid var(--tinta); }
  .hitos li { padding: 0 0 28px 24px; }
  .hitos li::before { top: 4px; left: -8px; }
}

/* Contacto */
.contacto { background: var(--tinta); color: #e9e6e0; }
.contacto h2 { color: #fff; }
.contacto .intro { color: #d4d0c8; }
.contacto a.correo { color: #fff; font-size: clamp(22px, 3vw, 30px); font-weight: 600; text-decoration: none; border-bottom: 2px solid var(--madera); }
.contacto a.correo:hover { color: var(--madera); }

/* Pie */
footer { background: #0f1112; color: #a8a49c; font-size: 14px; padding: 32px 0; }
footer .contenedor { display: flex; flex-wrap: wrap; gap: 12px 32px; justify-content: space-between; }
footer a { color: #d4d0c8; }

/* Páginas legales */
.legal { padding: 56px 0 88px; }
.legal .contenedor { max-width: 760px; }
.legal h1 { color: var(--tinta); font-size: 34px; margin: 0 0 24px; }
.legal h2 { font-size: 22px; margin: 36px 0 10px; }
.legal table { border-collapse: collapse; width: 100%; font-size: 16px; }
.legal td { border-bottom: 1px solid var(--linea); padding: 8px 10px 8px 0; vertical-align: top; }
.legal td:first-child { color: var(--suave); width: 38%; }
.pendiente { background: #fff3cd; padding: 0 4px; border-radius: 3px; }

/* Comparador boceto / resultado */
.comparador { position: relative; }
.comparador > img { aspect-ratio: 20 / 9; }
.comparador .capa-boceto { position: absolute; inset: 0 auto 0 0; width: 55%; overflow: hidden; border-right: 0; }
.comparador .capa-boceto img { position: absolute; inset: 0; height: 100%; width: auto; max-width: none; aspect-ratio: 20 / 9; object-fit: cover; }
.comparador .divisor { position: absolute; top: 0; bottom: 0; left: 55%; width: 3px; margin-left: -1.5px; background: #fff; box-shadow: 0 0 6px rgba(0,0,0,.35); pointer-events: none; }
.comparador .divisor span { position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%); width: 40px; height: 40px; border-radius: 50%; background: #fff; color: var(--tinta); display: flex; align-items: center; justify-content: center; font-size: 20px; box-shadow: 0 1px 6px rgba(0,0,0,.3); }
.comparador input[type=range] { position: absolute; inset: 0; width: 100%; height: 100%; margin: 0; opacity: 0; cursor: ew-resize; z-index: 2; }
.comparador figcaption { z-index: 1; pointer-events: none; }
@media (max-width: 760px) { .comparador > img, .comparador .capa-boceto img { aspect-ratio: 20 / 9; } }
@media (max-width: 760px) { .galeria figcaption { font-size: 12px; padding: 16px 10px 6px; } .comparador .divisor span { width: 32px; height: 32px; font-size: 16px; } }

/* Portada de ingeniería */
.hero-ing { background: var(--tinta); color: #e9e6e0; padding: 96px 0 88px; }
.hero-grid { display: grid; grid-template-columns: 1fr 1.05fr; gap: 56px; align-items: center; }
.hero-ing .etiqueta { color: var(--madera); opacity: 1; font-weight: 600; }
.hero-ing h1 { color: #fff; font-size: clamp(34px, 4.6vw, 54px); line-height: 1.08; margin: 0 0 20px; }
.hero-ing .lead { font-size: clamp(17px, 1.8vw, 19px); color: #d4d0c8; margin: 0 0 30px; max-width: 32em; }
.hero-boceto { margin: 0; background: #fff; border-radius: 6px; padding: 10px; box-shadow: 0 20px 50px rgba(0,0,0,.4); transform: rotate(-1.2deg); }
.hero-boceto img { border-radius: 3px; width: 100%; }
.acciones { display: flex; flex-wrap: wrap; gap: 12px; }
.boton-sec { display: inline-block; color: #fff; text-decoration: none; padding: 12px 20px; border: 1px solid rgba(255,255,255,.5); border-radius: 4px; font-weight: 600; }
.boton-sec:hover { border-color: #fff; }
@media (max-width: 860px) { .hero-grid { grid-template-columns: 1fr; gap: 40px; } .hero-ing { padding: 64px 0; } }

.cuatro { display: grid; grid-template-columns: repeat(4, 1fr); gap: 32px; }
@media (max-width: 980px) { .cuatro { grid-template-columns: 1fr 1fr; } }
@media (max-width: 560px) { .cuatro { grid-template-columns: 1fr; } }

.pasos { list-style: none; padding: 0; margin: 0 0 40px; display: grid; grid-template-columns: repeat(5, 1fr); counter-reset: none; border-top: 2px solid var(--tinta); }
.pasos li { padding: 14px 12px 0 0; font-weight: 600; color: var(--tinta); font-size: 16px; }
.pasos li span { display: block; font-size: 13px; letter-spacing: 2px; color: var(--madera-osc); margin-bottom: 4px; }
@media (max-width: 760px) { .pasos { grid-template-columns: 1fr 1fr; row-gap: 12px; } }
.g-i img { object-position: center top; }