/* Nexus Gas — estilos (versión institucional)
   Sin fuentes ni recursos externos: compatible con CSP estricta. */

:root {
  --ink: #0e2238;
  --navy: #12304d;
  --navy-2: #1b4166;
  --blue: #1f4e79;
  --blue-l: #2f6db0;
  --gold: #b98a35;
  --gold-l: #e3b66a;
  --paper: #f4f5f7;
  --white: #ffffff;
  --text: #1b2a3a;
  --muted: #556575;
  --line: #dde1e6;
  --tile: #e8edf2;
  --ok: #0f7b4b;
  --err: #b3261e;
  --radius: 12px;
  --maxw: 1160px;
  --font: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Georgia, "Times New Roman", serif;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font);
  font-size: 1.0625rem;
  line-height: 1.65;
  color: var(--text);
  background: var(--white);
  -webkit-font-smoothing: antialiased;
}
img, svg { max-width: 100%; display: block; }
a { color: var(--blue); text-underline-offset: 3px; }
a:hover { color: var(--ink); }
h1, h2, h3 { margin: 0 0 .55em; color: var(--ink); }
h1, h2 { font-family: var(--serif); font-weight: 600; letter-spacing: -.01em; line-height: 1.14; }
h1 { font-size: clamp(2.2rem, 4.6vw, 3.45rem); }
h2 { font-size: clamp(1.75rem, 3.2vw, 2.4rem); }
h3 { font-size: 1.1rem; font-weight: 700; line-height: 1.3; }
p { margin: 0 0 1em; }

:focus-visible { outline: 3px solid var(--blue-l); outline-offset: 3px; border-radius: 4px; }
.contact :focus-visible, .site-footer :focus-visible { outline-color: var(--gold-l); }

.skip-link {
  position: absolute; left: 1rem; top: -4rem; z-index: 100;
  background: var(--ink); color: var(--white); padding: .6rem 1rem; border-radius: 6px; font-weight: 600;
}
.skip-link:focus { top: 1rem; }

.container { width: min(100% - 2.5rem, var(--maxw)); margin-inline: auto; }
.section { padding: clamp(3.5rem, 7vw, 6rem) 0; }
.section--paper { background: var(--paper); }

.eyebrow {
  display: inline-flex; align-items: center; gap: .75rem;
  font-size: .78rem; font-weight: 700; letter-spacing: .16em; text-transform: uppercase;
  color: var(--blue); margin-bottom: 1.1rem;
}
.eyebrow::before { content: ""; width: 1.75rem; height: 2px; background: var(--gold); }
.section-head { max-width: 44rem; margin-bottom: 2.75rem; }
.section-head p { color: var(--muted); font-size: 1.12rem; }

/* ---------- Botones ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .5rem;
  font: inherit; font-weight: 600; font-size: .98rem; line-height: 1;
  padding: .95rem 1.5rem; border-radius: 8px; border: 1.5px solid transparent;
  text-decoration: none; cursor: pointer; transition: background .15s ease, border-color .15s ease, color .15s ease;
}
.btn--primary { background: var(--navy); color: var(--white); }
.btn--primary:hover { background: var(--ink); color: var(--white); }
.btn--ghost { border-color: #b9c4cf; color: var(--navy); background: transparent; }
.btn--ghost:hover { border-color: var(--navy); color: var(--ink); }
.btn--dark { background: var(--navy); color: var(--white); }
.btn--dark:hover { background: var(--ink); color: var(--white); }
.btn[disabled] { opacity: .6; cursor: progress; }

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255, 255, 255, .94);
  -webkit-backdrop-filter: saturate(140%) blur(8px); backdrop-filter: saturate(140%) blur(8px);
  border-bottom: 1px solid var(--line);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: 1rem; min-height: 4.5rem; }
.brand { display: inline-flex; align-items: center; gap: .7rem; text-decoration: none; color: var(--ink); }
.brand:hover { color: var(--ink); }
.brand img { width: 2.4rem; height: 2.4rem; flex: none; }
.brand-text { font-family: var(--serif); font-size: 1.4rem; font-weight: 700; letter-spacing: -.01em; }
.brand-text b { font-weight: 400; color: var(--blue); }

.nav { display: flex; align-items: center; gap: 2rem; }
.nav ul { display: flex; gap: 1.9rem; list-style: none; margin: 0; padding: 0; }
.nav a:not(.btn) { color: var(--text); text-decoration: none; font-weight: 500; font-size: .96rem; }
.nav a:not(.btn):hover { color: var(--blue); }
.nav .btn { padding: .7rem 1.2rem; font-size: .92rem; }
.nav-toggle {
  display: none; background: none; border: 1px solid #b9c4cf; color: var(--ink);
  border-radius: 8px; padding: .55rem .8rem; cursor: pointer; font: inherit; font-weight: 600; font-size: .95rem;
}

@media (max-width: 860px) {
  .nav-toggle { display: inline-flex; align-items: center; }
  .nav {
    position: absolute; inset: 4.5rem 0 auto 0; flex-direction: column; align-items: stretch; gap: 0;
    background: var(--white); padding: .5rem 1.25rem 1.5rem; border-bottom: 1px solid var(--line);
    box-shadow: 0 18px 30px -20px rgba(14,34,56,.3);
    display: none;
  }
  .nav.is-open { display: flex; }
  .nav ul { flex-direction: column; gap: 0; }
  .nav li a:not(.btn) { display: block; padding: .95rem 0; border-bottom: 1px solid var(--line); font-size: 1.05rem; }
  .nav .btn { margin-top: 1.1rem; }
}

/* ---------- Hero ---------- */
.hero { background: var(--paper); padding: clamp(3.5rem, 7vw, 5.5rem) 0 clamp(3.5rem, 7vw, 5rem); border-bottom: 1px solid var(--line); }
.hero-grid { display: grid; gap: 3.5rem; align-items: center; }
@media (min-width: 920px) { .hero-grid { grid-template-columns: 1.15fr .85fr; } }
.hero .lead { font-size: 1.2rem; max-width: 34rem; color: var(--muted); }
.hero-cta { display: flex; flex-wrap: wrap; gap: .9rem; margin: 2rem 0 0; }

.chain {
  background: var(--white); border: 1px solid var(--line); border-radius: 14px; padding: 1.9rem 1.9rem 1.6rem;
  box-shadow: 0 1px 2px rgba(14,34,56,.05), 0 24px 40px -28px rgba(14,34,56,.35);
}
.chain-title { font-size: .76rem; font-weight: 700; letter-spacing: .16em; text-transform: uppercase; color: var(--muted); margin: 0 0 1.4rem; }
.chain-list { list-style: none; margin: 0; padding: 0; counter-reset: c; }
.chain-list li { position: relative; counter-increment: c; padding: 0 0 1.35rem 3rem; }
.chain-list li:last-child { padding-bottom: 0; }
.chain-list li::before {
  content: counter(c); position: absolute; left: 0; top: .05rem; width: 2rem; height: 2rem; border-radius: 50%;
  display: grid; place-items: center; font-size: .85rem; font-weight: 700; color: var(--navy);
  background: var(--tile); border: 1px solid #c9d3dd;
}
.chain-list li::after { content: ""; position: absolute; left: 1rem; top: 2.2rem; bottom: .15rem; width: 1px; background: #c9d3dd; }
.chain-list li:last-child::after { display: none; }
.chain-list strong { display: block; color: var(--ink); line-height: 1.3; }
.chain-list span { color: var(--muted); font-size: .95rem; }
.chain-note { margin: 1.6rem 0 0; padding: 1rem 1.15rem; border-radius: 8px; background: var(--navy); color: #dbe6f0; font-size: .96rem; line-height: 1.5; border-left: 3px solid var(--gold); }
.chain-note b { color: var(--white); }

/* ---------- Franja de valores ---------- */
.strip { background: var(--white); border-bottom: 1px solid var(--line); }
.strip ul { list-style: none; margin: 0; padding: 0; display: grid; }
@media (min-width: 760px) { .strip ul { grid-template-columns: repeat(3, 1fr); } }
.strip li { padding: 1.6rem 1.5rem; border-top: 1px solid var(--line); }
.strip li:first-child { border-top: 0; }
@media (min-width: 760px) {
  .strip li { border-top: 0; border-left: 1px solid var(--line); }
  .strip li:first-child { border-left: 0; padding-left: 0; }
}
.strip strong { display: block; color: var(--ink); }
.strip span { color: var(--muted); font-size: .96rem; }

/* ---------- Servicios ---------- */
.cards { display: grid; gap: 1.25rem; grid-template-columns: repeat(auto-fit, minmax(16.5rem, 1fr)); }
.card { background: var(--white); border: 1px solid var(--line); border-radius: var(--radius); padding: 1.75rem; transition: border-color .2s ease; }
.card:hover { border-color: #9fb0c1; }
.card .icon { width: 2.9rem; height: 2.9rem; border-radius: 10px; display: grid; place-items: center; margin-bottom: 1.1rem; background: var(--tile); color: var(--navy); }
.card .icon svg { width: 1.45rem; height: 1.45rem; fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; }
.card p { color: var(--muted); margin: 0; font-size: 1rem; }

.sectors { display: flex; flex-wrap: wrap; gap: .6rem; list-style: none; padding: 0; margin: 2.5rem 0 0; }
.sectors li { padding: .5rem 1rem; border-radius: 6px; border: 1px solid var(--line); background: var(--white); font-weight: 600; font-size: .93rem; color: var(--navy); }

/* ---------- Proceso ---------- */
.steps { list-style: none; counter-reset: step; margin: 0; padding: 0; display: grid; gap: 1.25rem; grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr)); }
.steps li { counter-increment: step; padding: 1.6rem 1.5rem; border-radius: var(--radius); background: var(--white); border: 1px solid var(--line); border-top: 3px solid var(--navy); }
.steps li::before { content: counter(step, decimal-leading-zero); display: block; font-family: var(--serif); font-size: 2rem; font-weight: 600; line-height: 1; margin-bottom: .8rem; color: var(--gold); }
.steps p { color: var(--muted); margin: 0; font-size: 1rem; }

/* ---------- Nosotros ---------- */
.about { display: grid; gap: 3rem; align-items: start; }
@media (min-width: 900px) { .about { grid-template-columns: 1fr 1fr; gap: 4.5rem; } }
.about p { color: var(--muted); font-size: 1.1rem; }
.chip { display: inline-flex; align-items: center; gap: .6rem; padding: .5rem .9rem; border-radius: 6px; background: var(--paper); border: 1px solid var(--line); color: var(--navy); font-weight: 600; font-size: .92rem; margin-top: .5rem; }
.chip::before { content: ""; width: .5rem; height: .5rem; border-radius: 50%; background: var(--gold); }
.principles { display: grid; gap: 1rem; }
.principle { padding: 1.25rem 1.4rem; border-left: 3px solid var(--navy); background: var(--paper); border-radius: 0 var(--radius) var(--radius) 0; }
.principle h3 { margin-bottom: .25rem; }
.principle p { margin: 0; font-size: 1rem; }

/* ---------- Contacto ---------- */
.contact { background: var(--ink); color: #c9d6e2; }
.contact h2 { color: var(--white); }
.contact .eyebrow { color: var(--gold-l); }
.contact .eyebrow::before { background: var(--gold-l); }
.contact-grid { display: grid; gap: 3rem; }
@media (min-width: 960px) { .contact-grid { grid-template-columns: .85fr 1.15fr; gap: 4.5rem; } }
.contact-list { list-style: none; padding: 0; margin: 2rem 0 0; display: grid; gap: 1.4rem; }
.contact-list li { display: flex; gap: 1rem; align-items: flex-start; }
.contact-list .ci { flex: none; width: 2.6rem; height: 2.6rem; border-radius: 8px; display: grid; place-items: center; background: rgba(255,255,255,.08); color: var(--gold-l); }
.contact-list .ci svg { width: 1.2rem; height: 1.2rem; fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; }
.contact-list small { display: block; color: #93a8bb; font-size: .76rem; letter-spacing: .12em; text-transform: uppercase; font-weight: 700; }
.contact-list a { color: var(--white); text-decoration: none; font-weight: 500; word-break: break-word; }
.contact-list a:hover { color: var(--gold-l); text-decoration: underline; }

.form { background: var(--white); color: var(--text); border-radius: 14px; padding: clamp(1.5rem, 3vw, 2.25rem); box-shadow: 0 24px 50px -24px rgba(0,0,0,.5); }
.form h3 { font-family: var(--serif); font-weight: 600; font-size: 1.4rem; }
.form-grid { display: grid; gap: 1rem; grid-template-columns: 1fr; margin-top: 1.25rem; }
@media (min-width: 620px) { .form-grid { grid-template-columns: 1fr 1fr; } .form-grid .full { grid-column: 1 / -1; } }
.field label { display: block; font-weight: 600; font-size: .88rem; margin-bottom: .35rem; color: var(--ink); }
.field label .opt { font-weight: 400; color: var(--muted); }
.field input, .field select, .field textarea {
  width: 100%; font: inherit; color: var(--text); background: var(--white);
  padding: .8rem .9rem; border: 1px solid #b9c4cf; border-radius: 8px; transition: border-color .15s, box-shadow .15s;
}
.field textarea { min-height: 9rem; resize: vertical; }
.field input:focus, .field select:focus, .field textarea:focus { outline: none; border-color: var(--blue); box-shadow: 0 0 0 3px rgba(31,78,121,.18); }
.hp { position: absolute !important; left: -10000px; width: 1px; height: 1px; overflow: hidden; }
.form-foot { display: flex; flex-wrap: wrap; align-items: center; gap: 1rem 1.5rem; margin-top: 1.25rem; }
.form-note { font-size: .85rem; color: var(--muted); margin: 1rem 0 0; }
.form-status { margin: 1rem 0 0; padding: .8rem 1rem; border-radius: 8px; font-weight: 600; font-size: .96rem; display: none; }
.form-status.is-info, .form-status.is-ok, .form-status.is-error { display: block; }
.form-status.is-info { background: #e8eff6; color: #1a4568; }
.form-status.is-ok { background: #e3f3ea; color: var(--ok); }
.form-status.is-error { background: #fbeceb; color: var(--err); }

/* ---------- Footer ---------- */
.site-footer { background: #0a1a2b; color: #93a8bb; padding: 3rem 0 2rem; font-size: .95rem; }
.site-footer .brand, .site-footer .brand:hover { color: var(--white); }
.site-footer .brand-text b { color: #a9c3dc; }
.footer-grid { display: grid; gap: 2rem; }
@media (min-width: 760px) { .footer-grid { grid-template-columns: 1.4fr 1fr 1fr; } }
.site-footer h4 { color: var(--white); font-size: .78rem; letter-spacing: .14em; text-transform: uppercase; margin: 0 0 .9rem; }
.site-footer ul { list-style: none; padding: 0; margin: 0; display: grid; gap: .5rem; }
.site-footer a { color: #c0d0de; text-decoration: none; }
.site-footer a:hover { color: var(--gold-l); text-decoration: underline; }
.footer-bottom { margin-top: 2.5rem; padding-top: 1.5rem; border-top: 1px solid rgba(255,255,255,.1); display: flex; flex-wrap: wrap; justify-content: space-between; gap: .5rem 1.5rem; font-size: .85rem; }

/* ---------- Páginas simples (gracias / 404) ---------- */
.simple { min-height: 70vh; display: grid; place-items: center; text-align: center; padding: 4rem 0; background: var(--paper); }
.simple .container { max-width: 40rem; }
.simple .big { font-family: var(--serif); font-size: clamp(4rem, 12vw, 7rem); font-weight: 600; color: var(--gold); line-height: 1; margin-bottom: .5rem; }

/* ---------- Animación de entrada (sutil) ---------- */
.will-reveal { opacity: 0; transform: translateY(12px); transition: opacity .5s ease, transform .5s ease; }
.will-reveal.is-visible { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .will-reveal { opacity: 1; transform: none; transition: none; }
  .btn, .card { transition: none; }
}