.header {
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid rgba(0, 0, 0, 0.05);
  padding: 1rem 2rem;
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
}

.container {
  max-width: 1400px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.875rem;
  text-decoration: none;
  color: #0f172a;
  position: relative;
  padding: 0.5rem;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.logo::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(14, 165, 233, 0.1), rgba(139, 92, 246, 0.1));
  border-radius: 12px;
  opacity: 0;
  transition: opacity 0.3s;
}

.logo:hover::before {
  opacity: 1;
}

.logo-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, #0ea5e9, #8b5cf6);
  padding: 6px;
  border-radius: 10px;
  box-shadow: 0 4px 16px rgba(14, 165, 233, 0.4);
  position: relative;
  z-index: 1;
}

.logo-text {
  display: flex;
  flex-direction: column;
  gap: 0.125rem;
  position: relative;
  z-index: 1;
}

.logo-title {
  font-size: 1.125rem;
  font-weight: 700;
  line-height: 1;
  background: linear-gradient(135deg, #0ea5e9, #3b82f6);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.02em;
}

.logo-subtitle {
  font-size: 0.6875rem;
  color: #64748b;
  line-height: 1;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.nav {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.nav-link {
  padding: 0.625rem 1.25rem;
  border-radius: 10px;
  text-decoration: none;
  color: #64748b;
  font-size: 0.9375rem;
  font-weight: 600;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  align-items: center;
  gap: 0.5rem;
  position: relative;
  overflow: hidden;
  border: 1px solid transparent;
}

.nav-link::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(14, 165, 233, 0.1), rgba(139, 92, 246, 0.1));
  opacity: 0;
  transition: opacity 0.3s;
}

.nav-link:hover {
  color: #0f172a;
  border-color: rgba(0, 0, 0, 0.05);
  transform: translateY(-1px);
}

.nav-link:hover::before {
  opacity: 1;
}

.nav-icon {
  position: relative;
  z-index: 1;
}

.nav-link-active {
  background: linear-gradient(135deg, rgba(14, 165, 233, 0.1), rgba(34, 197, 94, 0.1));
  color: #0f172a;
  border-color: rgba(14, 165, 233, 0.2);
  box-shadow: 0 4px 16px rgba(14, 165, 233, 0.15);
}

.nav-link-active::before {
  opacity: 1;
}

.nav-link-active:hover {
  background-color: var(--color-accent-4);
}

.nav-icon {
  width: 18px;
  height: 18px;
}

@media (max-width: 768px) {
  .header {
    padding: var(--space-3) var(--space-4);
  }

  .logo-subtitle {
    display: none;
  }

  .nav-link {
    padding: var(--space-2) var(--space-3);
    font-size: var(--font-size-0);
  }

  .nav-icon {
    width: 16px;
    height: 16px;
  }
}

/* Branding Group */
.header-branding-group {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.brand-divider {
  width: 1px;
  height: 32px;
  background: rgba(0, 0, 0, 0.1);
}

/* zHeight Brand Styles */
.zheight-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  transition: opacity 0.2s;
}

.zheight-brand:hover {
  opacity: 0.9;
}

.zh-logo {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  font-size: 26px;
  font-weight: 800;
  color: #0f172a;
  letter-spacing: -0.5px;
  line-height: 1;
}

.zh-z {
  color: #06b6d4;
  /* Cyan to match the image */
}

.zh-tagline {
  color: #64748b;
  font-size: 14px;
  font-weight: 500;
  white-space: nowrap;
  border-left: 1px solid rgba(0, 0, 0, 0.1);
  padding-left: 12px;
  line-height: 1.2;
}

@media (max-width: 1024px) {
  .zh-tagline {
    display: none;
  }
}

@media (max-width: 768px) {
  .header-branding-group {
    gap: 1rem;
  }

  .brand-divider {
    display: none;
  }

  .zh-logo {
    font-size: 22px;
  }

  .zh-tagline {
    display: none;
  }
}