/* ============================================
   FitAuthority — Mobile-First Fitness Design System
   ============================================ */

/* --- CSS Custom Properties --- */
:root {
  --color-primary: #1a73e8;
  --color-primary-dark: #1557b0;
  --color-secondary: #0d9488;
  --color-accent: #f59e0b;
  --color-dark: #111827;
  --color-body: #374151;
  --color-muted: #6b7280;
  --color-light: #f9fafb;
  --color-white: #ffffff;
  --color-border: #e5e7eb;
  --color-success: #10b981;
  --color-warning: #f59e0b;
  --color-error: #ef4444;

  --font-display: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
  --font-body: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;

  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;

  --radius: 0.5rem;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.07);
  --shadow-lg: 0 10px 25px rgba(0,0,0,0.1);

  --max-width: 1200px;
  --content-width: 800px;
}

/* --- Reset & Base --- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 100%;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--color-body);
  background-color: var(--color-white);
  -webkit-font-smoothing: antialiased;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover,
a:focus {
  color: var(--color-primary-dark);
  text-decoration: underline;
}

ul, ol {
  padding-left: var(--space-lg);
}

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  color: var(--color-dark);
  line-height: 1.25;
  margin-bottom: var(--space-md);
  font-weight: 700;
}

h1 { font-size: clamp(1.75rem, 4vw, 2.5rem); }
h2 { font-size: clamp(1.4rem, 3vw, 2rem); margin-top: var(--space-2xl); }
h3 { font-size: clamp(1.15rem, 2.5vw, 1.5rem); margin-top: var(--space-xl); }
h4 { font-size: 1.15rem; margin-top: var(--space-lg); }
h5 { font-size: 1rem; }
h6 { font-size: 0.875rem; text-transform: uppercase; letter-spacing: 0.05em; color: var(--color-muted); }

p {
  margin-bottom: var(--space-md);
}

blockquote {
  border-left: 4px solid var(--color-primary);
  padding: var(--space-md) var(--space-lg);
  margin: var(--space-lg) 0;
  background: var(--color-light);
  border-radius: 0 var(--radius) var(--radius) 0;
  font-style: italic;
  color: var(--color-muted);
}

/* --- Layout --- */
.site-header {
  background: var(--color-white);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--space-md) var(--space-lg);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.site-logo {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--color-dark);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.site-logo:hover {
  text-decoration: none;
  color: var(--color-primary);
}

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

/* --- Navigation --- */
.main-nav ul {
  list-style: none;
  padding: 0;
  display: flex;
  gap: var(--space-lg);
  align-items: center;
}

.main-nav a {
  font-weight: 500;
  color: var(--color-body);
  font-size: 0.95rem;
  padding: var(--space-xs) 0;
  border-bottom: 2px solid transparent;
  transition: all 0.2s ease;
}

.main-nav a:hover,
.main-nav a[aria-current="page"] {
  color: var(--color-primary);
  border-bottom-color: var(--color-primary);
  text-decoration: none;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-sm);
  color: var(--color-dark);
}

.nav-toggle svg {
  width: 24px;
  height: 24px;
}

/* --- Mobile Navigation --- */
@media (max-width: 768px) {
  .nav-toggle {
    display: block;
  }

  .main-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--color-white);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-md);
  }

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

  .main-nav ul {
    flex-direction: column;
    padding: var(--space-md) var(--space-lg);
    gap: 0;
  }

  .main-nav li {
    border-bottom: 1px solid var(--color-border);
  }

  .main-nav li:last-child {
    border-bottom: none;
  }

  .main-nav a {
    display: block;
    padding: var(--space-md) 0;
    border-bottom: none;
  }
}

/* --- Main Content --- */
.page-main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--space-2xl) var(--space-lg);
}

.content-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-2xl);
}

@media (min-width: 1024px) {
  .content-layout {
    grid-template-columns: 1fr 300px;
  }
}

.content-area {
  max-width: var(--content-width);
}

/* --- Sidebar --- */
.sidebar {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.sidebar-widget {
  background: var(--color-light);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: var(--space-lg);
}

.sidebar-widget h3 {
  font-size: 1rem;
  margin-top: 0;
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-sm);
  border-bottom: 2px solid var(--color-primary);
}

.sidebar-widget ul {
  list-style: none;
  padding: 0;
}

.sidebar-widget li {
  padding: var(--space-xs) 0;
}

/* --- Hero Section --- */
.hero {
  background: linear-gradient(135deg, var(--color-dark) 0%, #1e3a5f 100%);
  color: var(--color-white);
  padding: var(--space-3xl) var(--space-lg);
  text-align: center;
}

.hero h1 {
  color: var(--color-white);
  margin-bottom: var(--space-md);
}

.hero p {
  font-size: 1.15rem;
  opacity: 0.9;
  max-width: 700px;
  margin: 0 auto var(--space-lg);
}

/* --- Silo Hub Cards --- */
.silo-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-lg);
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--space-2xl) var(--space-lg);
}

@media (min-width: 640px) {
  .silo-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .silo-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.silo-card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: var(--space-xl);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.silo-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.silo-card h3 {
  margin-top: 0;
  color: var(--color-primary);
}

.silo-card ul {
  list-style: none;
  padding: 0;
  margin-top: var(--space-md);
}

.silo-card li {
  padding: var(--space-xs) 0;
}

.silo-card a {
  font-size: 0.95rem;
}

/* --- Article Content --- */
.article-header {
  margin-bottom: var(--space-2xl);
  padding-bottom: var(--space-lg);
  border-bottom: 1px solid var(--color-border);
}

.article-header h1 {
  margin-bottom: var(--space-sm);
}

.article-meta {
  font-size: 0.875rem;
  color: var(--color-muted);
}

.article-body h2 {
  padding-top: var(--space-md);
  border-bottom: 1px solid var(--color-border);
  padding-bottom: var(--space-sm);
}

.article-body ul,
.article-body ol {
  margin-bottom: var(--space-md);
}

.article-body li {
  margin-bottom: var(--space-xs);
}

/* --- Breadcrumbs --- */
.breadcrumbs {
  padding: var(--space-md) var(--space-lg);
  max-width: var(--max-width);
  margin: 0 auto;
  font-size: 0.85rem;
  color: var(--color-muted);
}

.breadcrumbs ol {
  list-style: none;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
}

.breadcrumbs li::after {
  content: "›";
  margin-left: var(--space-xs);
  color: var(--color-muted);
}

.breadcrumbs li:last-child::after {
  content: "";
}

.breadcrumbs a {
  color: var(--color-muted);
}

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

/* --- Calculator Form --- */
.calculator-form {
  background: var(--color-light);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: var(--space-xl);
  margin: var(--space-xl) 0;
}

.calculator-form fieldset {
  border: none;
  padding: 0;
  margin: 0;
}

.calculator-form legend {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-dark);
  margin-bottom: var(--space-lg);
}

.form-group {
  margin-bottom: var(--space-md);
}

.form-group label {
  display: block;
  font-weight: 600;
  margin-bottom: var(--space-xs);
  color: var(--color-dark);
  font-size: 0.95rem;
}

.form-group input,
.form-group select {
  width: 100%;
  padding: var(--space-sm) var(--space-md);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  font-size: 1rem;
  font-family: var(--font-body);
  background: var(--color-white);
  transition: border-color 0.2s ease;
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(26, 115, 232, 0.15);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
}

.btn-calculate {
  display: inline-block;
  background: var(--color-primary);
  color: var(--color-white);
  font-weight: 600;
  font-size: 1rem;
  padding: var(--space-sm) var(--space-xl);
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background 0.2s ease;
  font-family: var(--font-body);
  margin-top: var(--space-md);
}

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

.calculator-result {
  background: var(--color-white);
  border: 2px solid var(--color-success);
  border-radius: var(--radius);
  padding: var(--space-lg);
  margin-top: var(--space-lg);
  display: none;
}

.calculator-result.is-visible {
  display: block;
}

.result-value {
  font-size: 2rem;
  font-weight: 800;
  color: var(--color-primary);
}

.result-label {
  font-size: 0.875rem;
  color: var(--color-muted);
  margin-top: var(--space-xs);
}

.result-category {
  font-size: 1.1rem;
  font-weight: 600;
  margin-top: var(--space-sm);
}

/* --- FAQ Section --- */
.faq-section {
  margin-top: var(--space-2xl);
}

.faq-item {
  border-bottom: 1px solid var(--color-border);
  padding: var(--space-lg) 0;
}

.faq-item h3 {
  margin-top: 0;
  font-size: 1.05rem;
  cursor: default;
}

.faq-item p {
  margin-top: var(--space-sm);
  color: var(--color-body);
}

/* --- Advertisement Placeholders --- */
.ad-slot {
  background: var(--color-light);
  border: 1px dashed var(--color-border);
  border-radius: var(--radius);
  padding: var(--space-lg);
  text-align: center;
  color: var(--color-muted);
  font-size: 0.8rem;
  min-height: 90px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.ad-slot-leaderboard {
  min-height: 90px;
  margin: var(--space-lg) 0;
}

.ad-slot-rectangle {
  min-height: 250px;
}

.ad-slot-in-content {
  min-height: 120px;
  margin: var(--space-xl) 0;
}

/* --- Disclaimer Box --- */
.disclaimer {
  background: #fef3c7;
  border: 1px solid #fcd34d;
  border-radius: var(--radius);
  padding: var(--space-lg);
  margin: var(--space-xl) 0;
  font-size: 0.9rem;
  color: #92400e;
}

.disclaimer strong {
  display: block;
  margin-bottom: var(--space-xs);
}

/* --- Internal Link Boxes --- */
.related-links {
  background: var(--color-light);
  border-radius: var(--radius);
  padding: var(--space-lg);
  margin: var(--space-xl) 0;
}

.related-links h3 {
  margin-top: 0;
  font-size: 1rem;
}

.related-links ul {
  list-style: none;
  padding: 0;
}

.related-links li {
  padding: var(--space-xs) 0;
}

.related-links a::before {
  content: "→ ";
  color: var(--color-primary);
}

/* --- Footer --- */
.site-footer {
  background: var(--color-dark);
  color: rgba(255, 255, 255, 0.7);
  padding: var(--space-3xl) var(--space-lg) var(--space-xl);
  margin-top: var(--space-3xl);
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-xl);
}

@media (min-width: 640px) {
  .footer-inner {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .footer-inner {
    grid-template-columns: repeat(4, 1fr);
  }
}

.footer-section h4 {
  color: var(--color-white);
  font-size: 1rem;
  margin-bottom: var(--space-md);
  margin-top: 0;
}

.footer-section ul {
  list-style: none;
  padding: 0;
}

.footer-section li {
  padding: var(--space-xs) 0;
}

.footer-section a {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.9rem;
}

.footer-section a:hover {
  color: var(--color-white);
}

.footer-bottom {
  max-width: var(--max-width);
  margin: var(--space-xl) auto 0;
  padding-top: var(--space-lg);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  text-align: center;
  font-size: 0.85rem;
}

/* --- Table --- */
table {
  width: 100%;
  border-collapse: collapse;
  margin: var(--space-lg) 0;
}

th, td {
  padding: var(--space-sm) var(--space-md);
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}

th {
  background: var(--color-light);
  font-weight: 600;
  color: var(--color-dark);
}

/* --- Utility --- */
.text-center { text-align: center; }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  border: 0;
}

/* --- Print Styles --- */
@media print {
  .site-header, .site-footer, .ad-slot, .nav-toggle { display: none; }
  body { font-size: 12pt; color: #000; }
  a { color: #000; text-decoration: underline; }
}