/* ─── Container ─────────────────────────────────────────── */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-padding);
}

/* ─── Nav ────────────────────────────────────────────────── */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--nav-height);
  display: flex;
  align-items: center;
  background: transparent;
  transition: background var(--transition-base), box-shadow var(--transition-base);
}

.site-nav.scrolled {
  background: var(--color-bg-dark);
  box-shadow: var(--shadow-md);
}

.site-nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.nav-logo img {
  height: 48px;
  width: auto;
  display: block;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.nav-item {
  position: relative;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  color: rgba(255,255,255,0.9);
  border-radius: var(--radius-sm);
  transition: color var(--transition-fast), background var(--transition-fast);
  white-space: nowrap;
}

.nav-link:hover,
.nav-link.active {
  color: #ffffff;
  background: rgba(255,255,255,0.1);
}

.nav-link svg {
  width: 14px;
  height: 14px;
  transition: transform var(--transition-fast);
  flex-shrink: 0;
}

.nav-item:hover .nav-link svg {
  transform: rotate(180deg);
}

/* Dropdown */
.nav-dropdown {
  position: absolute;
  top: calc(100% + var(--space-2));
  left: 0;
  min-width: 200px;
  background: var(--color-bg-dark);
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  padding: var(--space-2);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-8px);
  transition: opacity var(--transition-base), transform var(--transition-base), visibility var(--transition-base);
}

.nav-item:hover .nav-dropdown,
.nav-item:focus-within .nav-dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.nav-dropdown a {
  display: block;
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-sm);
  color: rgba(255,255,255,0.8);
  border-radius: var(--radius-sm);
  transition: color var(--transition-fast), background var(--transition-fast);
}

.nav-dropdown a:hover {
  color: #ffffff;
  background: rgba(255,255,255,0.08);
}

/* Mobile hamburger */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  cursor: pointer;
  padding: var(--space-1);
}

.nav-toggle span {
  display: block;
  height: 2px;
  background: #ffffff;
  border-radius: 2px;
  transition: transform var(--transition-base), opacity var(--transition-base);
}

.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ─── Hero ───────────────────────────────────────────────── */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  overflow: hidden;
  background-color: var(--color-bg-dark);
}

.hero-bg {
  position: absolute;
  inset: 0;
  background-image: url('../img/sercoin/genericas/Nidos_de_aves_en_acopio_de_aridos_cantera.jpg');
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    to bottom,
    rgba(10, 30, 15, 0.55) 0%,
    rgba(10, 30, 15, 0.72) 60%,
    rgba(10, 30, 15, 0.82) 100%
  );
}

.hero-content {
  position: relative;
  z-index: 1;
  padding: var(--space-8) var(--container-padding);
}

.hero-eyebrow {
  display: inline-block;
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-primary-light);
  margin-bottom: var(--space-4);
}

.hero-title {
  font-size: clamp(3rem, 8vw, 5.5rem);
  font-family: var(--font-heading);
  font-weight: var(--weight-bold);
  color: #ffffff;
  line-height: 1.05;
  margin-bottom: var(--space-6);
  letter-spacing: -0.02em;
}

.hero-subtitle {
  font-size: clamp(var(--text-lg), 2.5vw, var(--text-2xl));
  font-family: var(--font-body);
  font-weight: var(--weight-normal);
  color: rgba(255,255,255,0.85);
  max-width: 620px;
  margin: 0 auto var(--space-10);
  line-height: var(--leading-snug);
}

.hero-scroll-hint {
  position: absolute;
  bottom: var(--space-8);
  left: 50%;
  transform: translateX(-50%);
  z-index: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
  color: rgba(255,255,255,0.5);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  animation: bounce 2s ease-in-out infinite;
}

.hero-scroll-hint svg {
  width: 20px;
  height: 20px;
}

@keyframes bounce {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50% { transform: translateX(-50%) translateY(6px); }
}

/* ─── Sections ───────────────────────────────────────────── */
.section {
  padding-block: var(--space-24);
}

.section--alt {
  background-color: var(--color-bg-alt);
}

.section--dark {
  background-color: var(--color-primary);
  color: var(--color-text-inverse);
}

.section-header {
  margin-bottom: var(--space-12);
}

.section-label {
  display: inline-block;
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-primary-light);
  margin-bottom: var(--space-3);
}

.section--alt .section-label {
  color: var(--color-accent);
}

.section-title {
  color: var(--color-primary);
  margin-bottom: var(--space-5);
}

.section--alt .section-title {
  color: var(--color-primary);
}

.section-desc {
  font-size: var(--text-lg);
  max-width: 680px;
  color: var(--color-text-secondary);
  line-height: var(--leading-relaxed);
}

/* Two-column layouts */
.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-12);
  align-items: start;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-8);
}

/* ─── Page Header (inner pages) ──────────────────────────── */
.page-header {
  padding-top: calc(var(--nav-height) + var(--space-16));
  padding-bottom: var(--space-16);
  background: var(--color-primary);
  color: #ffffff;
}

.page-header h1 {
  color: #ffffff;
  font-size: clamp(var(--text-2xl), 4vw, var(--text-4xl));
}

.page-header .breadcrumb {
  display: flex;
  gap: var(--space-2);
  align-items: center;
  font-size: var(--text-sm);
  color: rgba(255,255,255,0.65);
  margin-top: var(--space-3);
}

.page-header .breadcrumb a {
  color: rgba(255,255,255,0.65);
  transition: color var(--transition-fast);
}

.page-header .breadcrumb a:hover {
  color: #ffffff;
}

.page-header .breadcrumb span {
  color: rgba(255,255,255,0.35);
}

/* ─── Footer ─────────────────────────────────────────────── */
.site-footer {
  background: var(--color-bg-footer);
  color: rgba(255,255,255,0.75);
}

.footer-main {
  padding: var(--space-20) 0 var(--space-12);
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: var(--space-12);
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: var(--space-5);
}

.footer-logo img {
  height: 44px;
  width: auto;
}

.footer-tagline {
  font-size: var(--text-sm);
  color: rgba(255,255,255,0.55);
  line-height: var(--leading-relaxed);
}

.footer-contact {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  margin-top: var(--space-2);
}

.footer-contact a {
  font-size: var(--text-sm);
  color: rgba(255,255,255,0.7);
  transition: color var(--transition-fast);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.footer-contact a:hover {
  color: #ffffff;
}

.footer-contact svg {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
  color: var(--color-primary-light);
}

.footer-col h6 {
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.4);
  margin-bottom: var(--space-5);
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.footer-links a {
  font-size: var(--text-sm);
  color: rgba(255,255,255,0.65);
  transition: color var(--transition-fast);
}

.footer-links a:hover {
  color: #ffffff;
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.08);
  padding: var(--space-6) 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: var(--text-xs);
  color: rgba(255,255,255,0.35);
}

/* ─── Back to top ────────────────────────────────────────── */
.back-to-top {
  position: fixed;
  bottom: var(--space-8);
  right: var(--space-8);
  z-index: 90;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--color-primary);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-md);
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity var(--transition-base), transform var(--transition-base), visibility var(--transition-base), background var(--transition-fast);
  cursor: pointer;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--color-primary-mid);
}

.back-to-top svg {
  width: 20px;
  height: 20px;
}

/* ─── Responsive ─────────────────────────────────────────── */
@media (max-width: 1024px) {
  .grid-2 {
    grid-template-columns: 1fr;
    gap: var(--space-8);
  }
  .grid-3 {
    grid-template-columns: 1fr 1fr;
  }
  .footer-main {
    grid-template-columns: 1fr 1fr;
  }
  .footer-brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 768px) {
  .nav-menu {
    display: none;
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: var(--color-bg-dark);
    flex-direction: column;
    align-items: stretch;
    padding: var(--space-4);
    gap: var(--space-1);
    box-shadow: var(--shadow-lg);
    max-height: calc(100vh - var(--nav-height));
    overflow-y: auto;
  }
  .nav-menu.open {
    display: flex;
  }
  .nav-toggle {
    display: flex;
  }
  .nav-link {
    padding: var(--space-3) var(--space-4);
    font-size: var(--text-base);
  }
  .nav-dropdown {
    position: static;
    opacity: 1;
    visibility: visible;
    transform: none;
    box-shadow: none;
    border: none;
    border-left: 2px solid rgba(255,255,255,0.1);
    border-radius: 0;
    padding: var(--space-1) 0 var(--space-1) var(--space-4);
    margin-top: var(--space-1);
    background: transparent;
    display: none;
  }
  .nav-item.open .nav-dropdown {
    display: block;
  }
  .grid-3 {
    grid-template-columns: 1fr;
  }
  .footer-main {
    grid-template-columns: 1fr;
    gap: var(--space-8);
    padding: var(--space-12) 0 var(--space-8);
  }
  .footer-brand {
    grid-column: auto;
  }
  .footer-bottom {
    flex-direction: column;
    gap: var(--space-2);
    text-align: center;
  }
  .section {
    padding-block: var(--space-16);
  }
}

@media (max-width: 480px) {
  .back-to-top {
    bottom: var(--space-4);
    right: var(--space-4);
  }
}