/* ==========================================================================
   Header Styles
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
  background-color: rgba(255, 255, 255, 0.98);
  border-bottom: 1px solid var(--color-border);
  transition: all 0.3s ease;
}

.site-header.header-scrolled {
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background-color: rgba(255, 255, 255, 0.85);
  box-shadow: 0 1px 8px rgba(0, 0, 0, 0.06);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: var(--site-max-width);
  margin: 0 auto;
  padding: 0 1rem;
}

/* Logo */
.site-logo {
  display: flex;
  align-items: center;
  text-decoration: none;
  flex-shrink: 0;
}

.logo-text {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: 0.02em;
}

/* Header Navigation */
.header-nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.header-nav a {
  color: var(--color-text);
  font-size: 0.875rem;
  font-weight: 500;
  transition: color 0.2s ease;
}

.header-nav a:hover {
  color: var(--color-sub-dark);
}

/* Header Actions */
.header-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 0;
  background: none;
  border: none;
  cursor: pointer;
}

.mobile-menu-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--color-text);
  border-radius: 1px;
  transition: all 0.3s ease;
}

.mobile-menu-toggle.is-active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu-toggle.is-active span:nth-child(2) {
  opacity: 0;
}

.mobile-menu-toggle.is-active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ==========================================================================
   Single Article Page
   ========================================================================== */
.single-article {
  padding-top: 2rem;
  padding-bottom: 2rem;
}

.article-header {
  margin-bottom: 2rem;
}

.article-title {
  margin: 0.75rem 0 0;
}

/* ==========================================================================
   Archive Title
   ========================================================================== */
.archive-title {
  margin-bottom: 2rem;
}

/* ==========================================================================
   Responsive Styles
   ========================================================================== */
@media (max-width: 1024px) {
  .header-nav {
    gap: 1rem;
  }
}

@media (max-width: 640px) {
  /* Mobile Menu */
  .mobile-menu-toggle {
    display: flex;
  }

  .header-nav {
    display: none;
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: var(--color-bg);
    flex-direction: column;
    padding: 1.5rem 1rem;
    border-bottom: 1px solid var(--color-border);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    gap: 0;
  }

  .header-nav.is-open {
    display: flex;
  }

  .header-nav a {
    display: block;
    padding: 0.75rem 0;
    font-size: 1rem;
    border-bottom: 1px solid var(--color-bg-light);
  }

  .header-actions {
    gap: 0.5rem;
  }

  .header-actions .btn {
    padding: 8px 16px;
    font-size: 0.8125rem;
  }

  /* Content adjustments */
  .single-article {
    padding-top: 1rem;
  }

  .article-content h2 {
    font-size: 1.25rem;
  }

  .article-content h3 {
    font-size: 1.125rem;
  }
}