/* Container */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

/* ============================================================
   Header
   ============================================================ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--header-height);
  display: flex;
  align-items: center;
  transition: background-color var(--transition-base),
    box-shadow var(--transition-base),
    backdrop-filter var(--transition-base);
}

.site-header--transparent {
  background-color: transparent;
}

.site-header--solid {
  background-color: rgba(13, 17, 23, 0.85);
  backdrop-filter: blur(20px) saturate(1.2);
  -webkit-backdrop-filter: blur(20px) saturate(1.2);
  box-shadow: 0 1px 0 var(--color-border), var(--shadow-md);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

/* Logo */
.site-logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-white);
  font-family: var(--font-heading);
  font-size: var(--text-base);
  letter-spacing: -0.01em;
  transition: opacity var(--transition-fast);
}

.site-logo:hover {
  color: var(--color-white);
  opacity: 1;
}

.site-logo img {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  transition: box-shadow var(--transition-base);
}

.site-logo:hover img {
  box-shadow: 0 0 12px rgba(110, 193, 228, 0.3), 0 0 24px rgba(110, 193, 228, 0.1);
}

.site-logo span {
  white-space: nowrap;
}

/* Navigation */
.main-nav {
  display: flex;
  align-items: center;
  gap: var(--space-8);
}

.nav-links {
  display: flex;
  list-style: none;
  gap: var(--space-1);
  padding: 0;
  margin: 0;
}

.nav-links a {
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  font-weight: 400;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-sm);
  position: relative;
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.nav-links a:hover {
  color: var(--color-white);
  background-color: rgba(255, 255, 255, 0.06);
}

.nav-links a.active {
  color: var(--color-sky);
  background-color: rgba(110, 193, 228, 0.08);
}

.nav-social a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.nav-social a:hover {
  color: var(--color-white);
  background-color: rgba(255, 255, 255, 0.06);
}

.nav-social svg {
  width: 18px;
  height: 18px;
  fill: currentColor;
}

/* Mobile Menu Toggle */
.menu-toggle {
  display: none;
  background: none;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  padding: var(--space-2);
  color: var(--color-text-muted);
  transition: color var(--transition-fast), border-color var(--transition-fast);
}

.menu-toggle:hover {
  color: var(--color-white);
  border-color: var(--color-border-hover);
}

.menu-toggle svg {
  width: 20px;
  height: 20px;
  fill: currentColor;
}

/* Mobile Navigation */
@media (max-width: 768px) {
  .menu-toggle {
    display: block;
  }

  .main-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    height: 100dvh;
    background-color: #0d1117;
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: var(--space-8) var(--container-padding);
    gap: var(--space-6);
    transform: translateX(100%);
    transition: transform var(--transition-base);
    z-index: 10000;
  }

  .main-nav.is-open {
    transform: translateX(0);
  }

  .nav-links {
    flex-direction: column;
    gap: var(--space-1);
  }

  .nav-links a {
    font-size: var(--text-lg);
    padding: var(--space-3) var(--space-4);
    letter-spacing: 0;
    text-transform: none;
  }

  .nav-links li {
    opacity: 0;
    transform: translateX(24px);
    transition: opacity 0.3s ease, transform 0.3s ease;
  }

  .main-nav.is-open .nav-links li {
    opacity: 1;
    transform: translateX(0);
  }

  .main-nav.is-open .nav-links li:nth-child(1) { transition-delay: 0.05s; }
  .main-nav.is-open .nav-links li:nth-child(2) { transition-delay: 0.1s; }
  .main-nav.is-open .nav-links li:nth-child(3) { transition-delay: 0.15s; }
  .main-nav.is-open .nav-links li:nth-child(4) { transition-delay: 0.2s; }

  .nav-social {
    opacity: 0;
    transition: opacity 0.3s ease 0.25s;
  }

  .main-nav.is-open .nav-social {
    opacity: 1;
  }

  .footer-nav {
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--space-4);
  }
}

/* ============================================================
   Main Content
   ============================================================ */
main {
  min-height: calc(100vh - var(--header-height));
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
  position: relative;
  background-color: var(--color-navy-deep);
  color: var(--color-text-muted);
  padding: var(--space-16) 0 var(--space-8);
  border-top: 1px solid var(--color-border);
}

/* Subtle top gradient edge */
.site-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg,
    transparent 0%,
    var(--color-sky) 30%,
    var(--color-green) 70%,
    transparent 100%
  );
  opacity: 0.3;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-6);
  text-align: center;
}

.footer-logo {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  opacity: 0.7;
  transition: opacity var(--transition-fast);
}

.footer-logo:hover {
  opacity: 1;
}

.footer-nav {
  display: flex;
  list-style: none;
  gap: var(--space-6);
  padding: 0;
  margin: 0;
}

.footer-nav a {
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  transition: color var(--transition-fast);
}

.footer-nav a:hover {
  color: var(--color-white);
}

.footer-tagline {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  max-width: 360px;
  line-height: 1.6;
}

.footer-copy {
  font-size: var(--text-xs);
  color: var(--color-gray-600);
  letter-spacing: 0.03em;
}

.footer-divider {
  width: 40px;
  height: 1px;
  background: linear-gradient(90deg, var(--color-sky), var(--color-green));
  border: none;
  opacity: 0.4;
}