/* ==========================================================================
   Header / Navigation
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(244, 248, 245, 0.9);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.site-header.is-scrolled {
  background: rgba(255, 255, 255, 0.96);
  border-bottom-color: var(--color-line-200);
  box-shadow: var(--shadow-sm);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding-top: 16px;
  padding-bottom: 16px;
}

.brand {
  display: flex;
  flex-direction: column;
  line-height: 1;
  position: relative;
  padding-left: 14px;
}

.brand::before {
  content: "";
  position: absolute;
  left: 0; top: 2px; bottom: 2px;
  width: 3px;
  background: var(--gradient-brand);
  border-radius: 2px;
}

.brand__name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 21px;
  letter-spacing: 0.2px;
  color: var(--color-ink-900);
}

.brand__di { color: var(--color-green-700); }
.brand__india { color: var(--color-amber-500); }

.brand__tagline {
  margin-top: 5px;
  font-family: var(--font-mono);
  font-size: 9px;
  font-weight: 500;
  letter-spacing: 0.14em;
  color: var(--color-ink-500);
  text-transform: uppercase;
}

.main-nav ul {
  display: flex;
  gap: 30px;
}

.main-nav a {
  font-size: 15px;
  font-weight: 500;
  color: var(--color-ink-700);
  padding: 6px 0;
  position: relative;
  transition: color 0.15s ease;
}

.main-nav a::after {
  content: "";
  position: absolute;
  left: 0; bottom: -2px;
  width: 0;
  height: 2px;
  background: var(--color-green-600);
  transition: width 0.2s ease;
}

.main-nav a:hover,
.main-nav a.active {
  color: var(--color-green-700);
}

.main-nav a:hover::after,
.main-nav a.active::after {
  width: 100%;
}

.header-cta { flex-shrink: 0; }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  padding: 6px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--color-ink-900);
  border-radius: 2px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

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

@media (max-width: 992px) {
  .header-cta { display: none; }

  .nav-toggle { display: flex; }

  .main-nav {
    position: absolute;
    top: 100%;
    left: 0; right: 0;
    background: var(--color-white);
    box-shadow: var(--shadow-md);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.25s ease;
  }

  .main-nav.is-open { max-height: 400px; }

  .main-nav ul {
    flex-direction: column;
    gap: 0;
    padding: 8px 24px 20px;
  }

  .main-nav a {
    display: block;
    padding: 12px 0;
    border-bottom: 1px solid var(--color-paper-100);
  }
}