/* ===== CSS Custom Properties (overridden by per-site theme.css) ===== */
:root {
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-accent: #f59e0b;
  --color-text: #1f2937;
  --color-text-light: #6b7280;
  --color-bg: #ffffff;
  --color-bg-alt: #f9fafb;
  --color-border: #e5e7eb;
  --font-heading: 'Inter', sans-serif;
  --font-body: 'Inter', sans-serif;
  --max-width: 1140px;
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 4rem;
  --spacing-xl: 6rem;
  --radius: 6px;
}

/* ===== Base Typography ===== */
body {
  font-family: var(--font-body);
  font-size: 1rem;
  color: var(--color-text);
  background: var(--color-bg);
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--spacing-sm);
}

h1 { font-size: clamp(2rem, 5vw, 3rem); }
h2 { font-size: clamp(1.5rem, 3.5vw, 2.25rem); }
h3 { font-size: clamp(1.25rem, 2.5vw, 1.5rem); }

p {
  margin-bottom: var(--spacing-sm);
  max-width: 70ch;
}

a:hover, a:focus-visible {
  color: var(--color-primary);
}

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

section {
  padding: var(--spacing-lg) 0;
}

/* ===== Header & Navigation ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  padding: var(--spacing-sm) 0;
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.site-logo {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-primary);
}

.nav-list {
  display: flex;
  gap: var(--spacing-md);
}

.nav-list a {
  font-weight: 500;
  transition: color 0.2s;
}

.nav-list a:hover {
  color: var(--color-primary);
}

/* Mobile nav toggle */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 4px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-xs);
}

.nav-toggle-bar {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text);
  transition: transform 0.2s;
}

@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .site-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    padding: var(--spacing-sm);
  }

  .site-nav.is-open {
    display: block;
  }

  .nav-list {
    flex-direction: column;
    gap: 0;
  }

  .nav-list a {
    display: block;
    padding: var(--spacing-xs) 0;
  }
}

/* ===== Hero ===== */
.hero {
  padding: var(--spacing-xl) 0;
  background: var(--color-bg-alt);
  text-align: center;
}

.hero h1 {
  margin-bottom: var(--spacing-sm);
}

.hero-sub {
  font-size: 1.25rem;
  color: var(--color-text-light);
  margin-bottom: var(--spacing-md);
  max-width: 60ch;
  margin-left: auto;
  margin-right: auto;
}

/* ===== Page Header ===== */
.page-header {
  padding: var(--spacing-lg) 0;
  background: var(--color-bg-alt);
  text-align: center;
}

.page-intro {
  font-size: 1.125rem;
  color: var(--color-text-light);
  max-width: 60ch;
  margin: 0 auto;
}

/* ===== Grid Layouts ===== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-md);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-md);
}

/* ===== Buttons ===== */
.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius);
  font-weight: 600;
  text-align: center;
  transition: background-color 0.2s, transform 0.1s;
  cursor: pointer;
  border: none;
}

.btn:active {
  transform: scale(0.98);
}

.btn-primary {
  background: var(--color-primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--color-primary-dark);
  color: #fff;
}

/* ===== Footer ===== */
.site-footer {
  background: var(--color-text);
  color: #d1d5db;
  padding: var(--spacing-lg) 0 var(--spacing-md);
}

.footer-heading {
  color: #fff;
  font-size: 1rem;
  margin-bottom: var(--spacing-sm);
}

.footer-bottom {
  margin-top: var(--spacing-md);
  padding-top: var(--spacing-sm);
  border-top: 1px solid #374151;
  font-size: 0.875rem;
  color: #9ca3af;
}

.site-footer a:hover {
  color: #fff;
}

/* ===== Article ===== */
.article-header {
  margin-bottom: var(--spacing-md);
}

.article-meta {
  color: var(--color-text-light);
  font-size: 0.875rem;
  display: flex;
  gap: var(--spacing-sm);
}

.article-body p {
  margin-bottom: var(--spacing-sm);
}

.article-body h2 {
  margin-top: var(--spacing-md);
}

/* ===== CTA Section ===== */
.cta-section {
  background: var(--color-bg-alt);
}

.cta-box {
  text-align: center;
  max-width: 600px;
  margin: 0 auto;
}

.cta-box h2 {
  margin-bottom: var(--spacing-xs);
}

.cta-box p {
  color: var(--color-text-light);
  margin-bottom: var(--spacing-md);
  margin-left: auto;
  margin-right: auto;
}