:root {
  --petroleo: #123a40; --verde: #2a9d8f; --verde-o: #1d7a6f; --coral: #e07a5f;
  --tinta: #132a2e; --suave: #566b6f; --linea: #d6e2e1; --fondo: #f3f7f6; --tinte: #e3f1ef; --blanco: #fff;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 76px; }
body { margin: 0; font-family: "Segoe UI", system-ui, -apple-system, "Helvetica Neue", Arial, sans-serif; color: var(--tinta); background: var(--blanco); line-height: 1.6; font-size: 17px; }
img { max-width: 100%; height: auto; display: block; }
a { color: var(--verde-o); }
.cont { max-width: 1120px; margin: 0 auto; padding: 0 20px; }
.estrecho { max-width: 820px; }

/* Cabecera */
.cab { position: sticky; top: 0; z-index: 10; background: rgba(255,255,255,.95); backdrop-filter: blur(6px); border-bottom: 1px solid var(--linea); }
.cab-in { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.marca { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--petroleo); font-weight: 800; font-size: 21px; }
nav { display: flex; align-items: center; gap: 22px; }
nav a { text-decoration: none; color: var(--tinta); font-weight: 600; font-size: 15px; }
nav a:hover { color: var(--verde-o); }
.btn-nav { background: var(--petroleo); color: #fff !important; padding: 8px 16px; border-radius: 999px; }

/* Portada */
.hero { background: radial-gradient(circle at 75% 40%, #1b5158, var(--petroleo) 70%); color: #fff; padding: 72px 0 80px; }
.hero-in { display: grid; grid-template-columns: 1.15fr 1fr; gap: 48px; align-items: center; }
.etiqueta { margin: 0 0 12px; color: #7fd3c7; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; font-size: 13px; }
h1 { font-size: clamp(34px, 5vw, 54px); line-height: 1.08; margin: 0 0 18px; letter-spacing: -.01em; }
.entrada { font-size: 19px; color: #d4e6e4; margin: 0 0 26px; max-width: 34em; }
.cuenta { border-left: 4px solid var(--verde); padding: 4px 0 4px 16px; margin: 0 0 28px; }
.cuenta em { display: block; font-style: normal; color: #7fd3c7; font-weight: 700; font-size: 14px; letter-spacing: .04em; text-transform: uppercase; }
.cuenta strong { display: block; font-size: 24px; }
.cuenta span { color: #c3d9d6; font-size: 15px; }
.botones { display: flex; flex-wrap: wrap; gap: 12px; }
.btn { display: inline-block; background: var(--verde); color: #fff; text-decoration: none; font-weight: 700; padding: 12px 22px; border-radius: 999px; border: 2px solid var(--verde); transition: background .2s; }
.btn:hover { background: var(--verde-o); border-color: var(--verde-o); }
.btn-sec { background: transparent; color: inherit; border-color: currentColor; }
.hero .btn-sec { color: #fff; }
.tarjeta .btn-sec { color: var(--petroleo); }
.btn-sec:hover { background: rgba(42,157,143,.12); border-color: var(--verde); }
.hero-video { position: relative; display: block; border-radius: 14px; overflow: hidden; box-shadow: 0 20px 50px rgba(0,0,0,.35); text-decoration: none; }
.hero-video img { width: 100%; aspect-ratio: 16/9; object-fit: cover; }
.play { position: absolute; left: 50%; top: 45%; width: 74px; height: 74px; margin: -37px 0 0 -37px; border-radius: 50%; background: rgba(18,58,64,.85); border: 3px solid #fff; }
.play::after { content: ""; position: absolute; left: 29px; top: 21px; border-left: 22px solid #fff; border-top: 14px solid transparent; border-bottom: 14px solid transparent; }
.pie-video { position: absolute; left: 0; right: 0; bottom: 0; padding: 10px 14px; background: linear-gradient(transparent, rgba(0,0,0,.7)); color: #fff; font-weight: 700; }

/* Secciones */
.seccion { padding: 72px 0; }
.fondo { background: var(--fondo); }
h2 { font-size: clamp(28px, 3.4vw, 38px); color: var(--petroleo); margin: 0 0 10px; line-height: 1.15; }
h3 { margin: 0 0 8px; font-size: 20px; color: var(--petroleo); }
.intro { color: var(--suave); margin: 0 0 30px; font-size: 18px; }
.dos { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; }
.tarjeta { background: #fff; border: 1px solid var(--linea); border-top: 5px solid var(--verde); border-radius: 12px; padding: 26px; }
.tarjeta p { margin: 0 0 18px; }
.tarjeta p:last-child { margin-bottom: 0; }
.nota { margin: 24px 0 0; padding: 16px 20px; background: var(--tinte); border-radius: 10px; }
.rejilla { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 30px; }
.punto { background: #fff; border-radius: 12px; padding: 24px; border: 1px solid var(--linea); }
.punto p { margin: 0; color: #2c4549; font-size: 16px; }
.num { display: inline-grid; place-items: center; width: 36px; height: 36px; border-radius: 50%; background: var(--petroleo); color: #fff; font-weight: 800; margin-bottom: 12px; }

/* Vídeos */
.videos { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 18px; }
.video { text-decoration: none; color: var(--tinta); font-weight: 600; font-size: 15px; line-height: 1.35; }
.video img { border-radius: 10px; aspect-ratio: 16/9; object-fit: cover; width: 100%; margin-bottom: 8px; border: 1px solid var(--linea); }
.video:hover span { color: var(--verde-o); }

/* Preguntas */
details { background: #fff; border: 1px solid var(--linea); border-radius: 10px; margin-bottom: 10px; }
summary { cursor: pointer; padding: 16px 20px; font-weight: 700; color: var(--petroleo); list-style: none; position: relative; padding-right: 48px; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; position: absolute; right: 20px; top: 12px; font-size: 24px; color: var(--verde); }
details[open] summary::after { content: "–"; }
details p { margin: 0; padding: 0 20px 18px; }

/* Pie */
.pie { background: var(--petroleo); color: #c3d9d6; padding: 32px 0; font-size: 14px; }
.pie a { color: #fff; }
.pie p { margin: 6px 0; }

/* Páginas legales */
.legal { padding: 56px 0 72px; }
.legal h1 { color: var(--petroleo); font-size: 36px; }
.legal h2 { font-size: 22px; margin-top: 32px; }
.pendiente { background: #fff4d6; padding: 0 4px; border-radius: 4px; }

@media (max-width: 860px) {
  nav a:not(.btn-nav) { display: none; }
  .hero { padding: 48px 0 56px; }
  .hero-in, .dos { grid-template-columns: 1fr; gap: 32px; }
  .rejilla { grid-template-columns: 1fr; }
  .seccion { padding: 52px 0; }
}
@media (max-width: 400px) { body { font-size: 16px; } .entrada { font-size: 17px; } }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

/* Páginas de artículo */
.articulo { padding: 48px 0 64px; }
.miga { font-size: 14px; color: var(--suave); margin: 0 0 18px; }
.miga a { color: var(--suave); }
.articulo h1 { color: var(--petroleo); font-size: clamp(30px, 4.4vw, 44px); margin-bottom: 14px; }
.articulo .resumen { font-size: 19px; color: #2c4549; margin: 0 0 28px; }
.clave { background: var(--tinte); border-left: 5px solid var(--verde); border-radius: 10px; padding: 18px 22px; margin: 0 0 32px; }
.clave h2 { font-size: 18px; margin: 0 0 8px; color: var(--petroleo); }
.clave ul { margin: 0; padding-left: 20px; }
.articulo h2 { font-size: 26px; margin: 40px 0 10px; }
.articulo h3 { font-size: 20px; margin: 26px 0 8px; }
.articulo p, .articulo li { color: #22393d; }
.articulo table { width: 100%; border-collapse: collapse; margin: 16px 0 24px; font-size: 16px; }
.articulo th, .articulo td { border: 1px solid var(--linea); padding: 10px 12px; text-align: left; vertical-align: top; }
.articulo th { background: var(--fondo); color: var(--petroleo); }
.gris { background: #fff4e6; border-left: 5px solid var(--coral); border-radius: 10px; padding: 14px 20px; margin: 20px 0; }
.ver-video { display: flex; gap: 16px; align-items: center; background: var(--fondo); border-radius: 12px; padding: 14px; text-decoration: none; color: var(--tinta); margin: 28px 0; }
.ver-video img { width: 200px; border-radius: 8px; aspect-ratio: 16/9; object-fit: cover; flex: none; }
.ver-video strong { display: block; color: var(--petroleo); }
.cta { background: var(--petroleo); color: #fff; border-radius: 14px; padding: 26px; margin: 40px 0 28px; }
.cta h2 { color: #fff; margin: 0 0 8px; font-size: 22px; }
.cta p { color: #d4e6e4; margin: 0 0 16px; }
.fuentes { font-size: 15px; color: var(--suave); border-top: 1px solid var(--linea); padding-top: 18px; margin-top: 32px; }
.relacionadas { margin-top: 28px; }
.relacionadas ul { padding-left: 20px; }
.actualizado { font-size: 14px; color: var(--suave); }
@media (max-width: 600px) { .ver-video { flex-direction: column; align-items: stretch; } .ver-video img { width: 100%; } }

/* Guías en la portada */
.guias { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.guia { display: block; text-decoration: none; background: #fff; border: 1px solid var(--linea); border-left: 5px solid var(--verde); border-radius: 10px; padding: 18px 20px; color: var(--tinta); transition: border-color .2s, transform .2s; }
.guia strong { display: block; color: var(--petroleo); font-size: 18px; margin-bottom: 4px; }
.guia span { color: var(--suave); font-size: 15px; }
.guia:hover { border-color: var(--verde); transform: translateY(-2px); }
@media (max-width: 860px) { .guias { grid-template-columns: 1fr; } }
.articulo .clave h2 { margin: 0 0 8px; font-size: 18px; }
.articulo .cta h2 { margin: 0 0 8px; font-size: 22px; }
.articulo table { display: block; overflow-x: auto; }

/* Caja de autora */
.autora { display: flex; gap: 16px; align-items: flex-start; background: var(--fondo); border-radius: 12px; padding: 18px 20px; margin: 32px 0; }
.autora .ini { flex: none; width: 52px; height: 52px; border-radius: 50%; background: var(--petroleo); color: #fff; display: grid; place-items: center; font-weight: 800; font-size: 20px; }
.autora p { margin: 0; font-size: 15px; color: #2c4549; }
.autora strong { color: var(--petroleo); }
.firma { margin: 32px 0 0; font-size: 15px; color: var(--suave); font-style: italic; }