header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
  z-index: 1000;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: var(--transition);
}

header.scrolled {
  box-shadow: var(--shadow-md);
}

.header-container {
  max-width: 1200px;
  margin: 0 auto;
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-primary);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: var(--transition);
}

.logo:hover {
  color: var(--color-accent);
}

.logo-icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
  border-radius: var(--border-radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 700;
  font-size: 1.25rem;
}

nav {
  flex: 1;
  display: flex;
  justify-content: flex-end;
}

nav ul {
  display: flex;
  list-style: none;
  gap: 2rem;
  align-items: center;
}

nav a {
  color: var(--color-text);
  text-decoration: none;
  font-weight: 500;
  transition: var(--transition);
  padding: 0.5rem 0;
  border-bottom: 2px solid transparent;
  position: relative;
}

nav a:hover,
nav a.active {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

nav a.active::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--color-accent);
}

.menu-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--color-primary);
  padding: 0.5rem;
  transition: var(--transition);
}

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

.header-cta {
  padding: 0.75rem 1.5rem;
  font-size: 0.875rem;
}

@media (max-width: 768px) {
  header {
    padding: 1rem;
  }

  .menu-toggle {
    display: block;
  }

  nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: white;
    padding: 1rem;
    box-shadow: var(--shadow-lg);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
  }

  nav.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  nav ul {
    flex-direction: column;
    gap: 0;
  }

  nav a {
    padding: 1rem 0;
    border-bottom: 1px solid var(--color-border);
    display: block;
  }

  nav a:last-child {
    border-bottom: none;
  }

  .header-cta {
    width: 100%;
    margin-top: 1rem;
  }
}
