/* =========================================================
   Back&Front · bfgroup.mx — Stylesheet
   Brand palette: red #EA2127, ink #0E0F12, white #FFFFFF
   ========================================================= */

:root {
  --red: #EA2127;
  --red-dark: #B5181D;
  --black: #0E0F12;
  --ink: #14171C;
  --charcoal: #1F2126;
  --graphite: #2E3138;
  --text: #1A1A1A;
  --muted: #6B7280;
  --line: #E5E7EB;
  --soft: #F7F7F8;
  --white: #FFFFFF;

  --maxw: 1240px;
  --pad-x: clamp(1.25rem, 4vw, 3rem);
  --section-y: clamp(4rem, 9vw, 7rem);

  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--font);
  color: var(--text);
  line-height: 1.55;
  font-size: 16px;
  background: var(--white);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: inherit; text-decoration: none; transition: color .18s ease; }
img { display: block; max-width: 100%; height: auto; }

.container { max-width: var(--maxw); margin: 0 auto; padding-left: var(--pad-x); padding-right: var(--pad-x); }

.accent { color: var(--red); }

.eyebrow {
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .25em;
  color: var(--red);
  text-transform: uppercase;
  margin-bottom: .75rem;
  position: relative;
  padding-bottom: .85rem;
}
.eyebrow::after {
  content: '';
  position: absolute;
  left: 0; bottom: 0;
  width: 38px; height: 3px;
  background: var(--red);
}
.eyebrow--light { color: var(--red); }

/* ============ NAV ============ */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,.92);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav__row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}
.nav__brand { display: flex; align-items: center; gap: .75rem; font-weight: 800; }
.nav__mark { width: 36px; height: 36px; }
.nav__wordmark { font-size: 1.05rem; letter-spacing: .03em; color: var(--ink); }
.nav__amp { color: var(--red); }
.nav__links { display: flex; align-items: center; gap: 1.75rem; }
.nav__links a { font-size: .92rem; font-weight: 500; color: var(--ink); }
.nav__links a:hover { color: var(--red); }
.nav__cta {
  background: var(--red);
  color: var(--white) !important;
  padding: .55rem 1.2rem;
  border-radius: 2px;
  font-weight: 600 !important;
  transition: background .18s ease, transform .18s ease;
}
.nav__cta:hover { background: var(--red-dark); transform: translateY(-1px); }

@media (max-width: 820px) {
  .nav__links a:not(.nav__cta) { display: none; }
}

/* ============ HERO ============ */
.hero {
  background: var(--black);
  color: var(--white);
  padding: clamp(5rem, 12vw, 8rem) 0 clamp(4rem, 9vw, 6rem);
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 6px;
  background: var(--red);
}
.hero__inner { position: relative; }
.hero__title {
  font-size: clamp(2.2rem, 5.2vw, 4.4rem);
  font-weight: 800;
  letter-spacing: -.02em;
  line-height: 1.05;
  margin: 1.25rem 0;
  max-width: 16ch;
}
.hero__lead {
  font-size: clamp(1rem, 1.5vw, 1.25rem);
  color: #CFD2D7;
  max-width: 58ch;
  margin-top: 1.5rem;
}
.hero__actions {
  margin-top: 2.5rem;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}
.btn {
  display: inline-flex;
  align-items: center;
  padding: .95rem 1.6rem;
  font-weight: 600;
  font-size: .95rem;
  letter-spacing: .02em;
  border-radius: 2px;
  transition: transform .18s ease, background .18s ease, color .18s ease, border-color .18s ease;
  border: 2px solid transparent;
}
.btn--white {
  background: var(--white);
  color: var(--ink);
}
.btn--white:hover { background: var(--red); color: var(--white); transform: translateY(-1px); }
.btn--ghost {
  background: transparent;
  color: var(--white);
  border-color: rgba(255,255,255,.4);
}
.btn--ghost:hover { border-color: var(--white); transform: translateY(-1px); }

.hero__stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  margin-top: 3.5rem;
  padding-top: 2rem;
  border-top: 1px solid rgba(255,255,255,.12);
}
.hero__stats > div {
  display: flex;
  flex-direction: column;
}
.hero__stats strong {
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  font-weight: 800;
  color: var(--white);
  line-height: 1;
}
.hero__stats span {
  font-size: .8rem;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: #9CA3AF;
  margin-top: .35rem;
}
@media (max-width: 640px) {
  .hero__stats { grid-template-columns: repeat(2, 1fr); }
}

/* ============ SECTIONS ============ */
.section {
  padding: var(--section-y) 0;
}
.section--soft { background: var(--soft); }
.section--dark { background: var(--black); color: var(--white); }
.section--cta {
  background: var(--red);
  color: var(--white);
}
.section__title {
  font-size: clamp(1.7rem, 3.4vw, 2.7rem);
  font-weight: 800;
  letter-spacing: -.015em;
  line-height: 1.15;
  color: var(--ink);
  max-width: 28ch;
  margin-bottom: 1.5rem;
}
.section__title--light { color: var(--white); }
.section__lead {
  font-size: 1.05rem;
  color: var(--graphite);
  max-width: 70ch;
  line-height: 1.7;
}

/* ============ GRIDS & CARDS ============ */
.grid {
  display: grid;
  gap: 1rem;
  margin-top: 3rem;
}
.grid--4 { grid-template-columns: repeat(4, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
@media (max-width: 980px) { .grid--4 { grid-template-columns: repeat(2, 1fr); } .grid--3 { grid-template-columns: 1fr; } }
@media (max-width: 560px) { .grid--4 { grid-template-columns: 1fr; } }

.card {
  background: var(--white);
  border: 1px solid var(--line);
  padding: 1.5rem 1.4rem;
  border-left: 3px solid var(--red);
  transition: transform .2s ease, box-shadow .2s ease;
}
.card:hover { transform: translateY(-3px); box-shadow: 0 12px 32px rgba(14,15,18,.08); }
.card h3 { font-size: 1rem; font-weight: 700; color: var(--ink); margin-bottom: .6rem; }
.card p { font-size: .9rem; color: var(--muted); line-height: 1.55; }

/* Sistemas (numerados) */
.syscard {
  background: var(--white);
  border: 1px solid var(--line);
  border-top: 3px solid var(--red);
  padding: 1.4rem 1.3rem;
  transition: transform .2s ease, box-shadow .2s ease;
}
.syscard:hover { transform: translateY(-3px); box-shadow: 0 12px 32px rgba(14,15,18,.08); }
.syscard__num {
  display: inline-block;
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--red);
  letter-spacing: .1em;
  margin-bottom: .55rem;
}
.syscard h4 { font-size: .95rem; font-weight: 700; color: var(--ink); margin-bottom: .55rem; }
.syscard p { font-size: .85rem; color: var(--muted); line-height: 1.55; }

/* Sectores (colored blocks) */
.grid--sectors { gap: 1rem; }
.sector {
  padding: 2.2rem 1.7rem 2rem;
  position: relative;
  min-height: 280px;
  display: flex;
  flex-direction: column;
}
.sector::before {
  content: '';
  position: absolute;
  left: 1.7rem; top: 1.7rem;
  width: 32px; height: 3px;
  background: var(--red);
}
.sector__num {
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .25em;
  margin-top: 1.5rem;
  margin-bottom: .5rem;
}
.sector h3 { font-size: 1.35rem; font-weight: 800; margin-bottom: auto; }
.sector p { font-size: .9rem; line-height: 1.55; margin-top: 1rem; }
.sector--dark { background: var(--charcoal); color: var(--white); }
.sector--dark .sector__num, .sector--dark p { color: #CFD2D7; }
.sector--red { background: var(--red); color: var(--white); }
.sector--red::before { background: var(--white); }
.sector--red .sector__num, .sector--red p { color: rgba(255,255,255,.92); }
.sector--ink { background: var(--ink); color: var(--white); }
.sector--ink .sector__num, .sector--ink p { color: #CFD2D7; }
.sector--white { background: var(--white); color: var(--ink); border: 1px solid var(--line); }
.sector--white .sector__num { color: var(--red); }
.sector--white p { color: var(--muted); }

/* Casos / clientwall */
.clientwall {
  display: flex;
  flex-wrap: wrap;
  gap: .6rem .5rem;
  list-style: none;
  margin: 3rem 0 1.5rem;
}
.clientwall li {
  background: var(--white);
  border: 1px solid var(--line);
  padding: .65rem 1.1rem;
  font-weight: 600;
  font-size: .92rem;
  color: var(--ink);
  letter-spacing: .02em;
}
.clientwall__note { color: var(--muted); font-size: .95rem; max-width: 70ch; }

/* Alianzas (sobre fondo dark) */
.grid--alliances { gap: 1.25rem; }
.alliance {
  background: var(--charcoal);
  border: 1px solid var(--graphite);
  padding: 2.5rem 1.8rem;
  text-align: center;
}
.alliance h3 {
  font-size: 2rem;
  font-weight: 800;
  letter-spacing: .12em;
  color: var(--white);
  margin-bottom: .35rem;
}
.alliance__tier {
  display: block;
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .25em;
  color: var(--red);
  margin-bottom: 1.5rem;
}
.alliance p { color: #CFD2D7; font-size: .92rem; line-height: 1.6; }

/* CTA */
.cta { text-align: center; }
.cta__title {
  font-size: clamp(1.8rem, 4vw, 3rem);
  font-weight: 800;
  letter-spacing: -.015em;
  line-height: 1.15;
  margin-bottom: 1.25rem;
}
.cta__title .accent { color: var(--black); }
.cta__lead { font-size: 1.1rem; color: rgba(255,255,255,.92); margin-bottom: 3rem; }
.cta__contacts {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  max-width: 900px;
  margin: 0 auto;
  padding-top: 2rem;
  border-top: 1px solid rgba(255,255,255,.25);
}
.cta__contacts > div { display: flex; flex-direction: column; gap: .4rem; }
.cta__lbl { font-size: .72rem; font-weight: 700; letter-spacing: .25em; color: var(--black); }
.cta__contacts a, .cta__contacts span { color: var(--white); font-weight: 500; }
.cta__contacts a:hover { color: var(--black); }
@media (max-width: 720px) {
  .cta__contacts { grid-template-columns: 1fr; gap: 1.5rem; }
}

/* Footer */
.footer {
  background: var(--ink);
  color: #9CA3AF;
  padding: 2.5rem 0;
}
.footer__inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1.5rem;
}
.footer__brand { display: flex; align-items: center; gap: .8rem; }
.footer__brand img { width: 34px; height: 34px; }
.footer__brand strong { color: var(--white); font-weight: 800; letter-spacing: .03em; display: block; }
.footer__brand small { font-size: .75rem; letter-spacing: .15em; text-transform: uppercase; color: var(--red); }
.footer__copy { font-size: .85rem; }