/* BrainFortUSA.com — Evidence-Based Health Publishing Design System (2026) */
:root {
  --font-sans: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-heading: 'Outfit', 'Inter', system-ui, sans-serif;

  --color-primary: #0369a1;
  --color-primary-hover: #0369a1;
  --color-dark: #0f172a;
  --color-dark-surface: #1e293b;
  --color-light: #f8fafc;
  --color-border: #e2e8f0;
  --color-text-main: #334155;
  --color-text-heading: #0f172a;
  --color-text-muted: #475569;

  --color-evidence-human: #059669;
  --color-evidence-human-bg: #ecfdf5;
  --color-evidence-preliminary: #d97706;
  --color-evidence-preliminary-bg: #fffbeb;
  --color-evidence-caution: #dc2626;
  --color-evidence-caution-bg: #fef2f2;

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --radius-pill: 9999px;

  --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  background-color: var(--color-light);
  color: var(--color-text-main);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

/* Container */
.container {
  width: 100%;
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 20px;
}

.article-container {
  max-width: 860px;
  margin: 40px auto;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  color: var(--color-text-heading);
  font-weight: 700;
  line-height: 1.3;
  margin-top: 1.6em;
  margin-bottom: 0.6em;
}

h1 { font-size: 2.5rem; letter-spacing: -0.02em; margin-top: 0.5em; }
h2 { font-size: 1.85rem; border-bottom: 2px solid #e2e8f0; padding-bottom: 8px; }
h3 { font-size: 1.35rem; }
h4 { font-size: 1.1rem; }

p { margin-bottom: 1.25rem; font-size: 1.05rem; }
ul, ol { margin-bottom: 1.25rem; padding-left: 1.5rem; }
li { margin-bottom: 0.5rem; font-size: 1.05rem; }

a {
  color: var(--color-primary);
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: color 0.2s ease;
}
a:hover { color: var(--color-primary-hover); }

/* Affiliate Disclosure Bar */
.affiliate-disclosure {
  background: #f1f5f9;
  border: 1px solid var(--color-border);
  padding: 10px 16px;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  color: var(--color-text-muted);
  margin-bottom: 24px;
}

/* Editorial Meta Line */
.editorial-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  font-size: 0.9rem;
  color: var(--color-text-muted);
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--color-border);
}
.editorial-meta strong { color: var(--color-dark); }

/* Header */
.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  padding: 14px 0;
}
.header__inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.35rem;
  color: var(--color-dark);
  text-decoration: none;
}
.brand__mark {
  background: linear-gradient(135deg, #0284c7 0%, #0f172a 100%);
  color: #ffffff;
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 0.9rem;
}
.nav ul {
  display: flex;
  gap: 24px;
  list-style: none;
}
.nav a {
  color: var(--color-text-main);
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
}
.nav a:hover, .nav a.active {
  color: var(--color-primary);
}

/* Evidence Callout Boxes */
.evidence-box {
  padding: 20px;
  border-radius: var(--radius-md);
  margin: 24px 0;
  border-left: 4px solid;
}
.evidence--human {
  background: var(--color-evidence-human-bg);
  border-color: var(--color-evidence-human);
}
.evidence--human h4 { color: #065f46; margin-top: 0; }

.evidence--preliminary {
  background: var(--color-evidence-preliminary-bg);
  border-color: var(--color-evidence-preliminary);
}
.evidence--preliminary h4 { color: #92400e; margin-top: 0; }

.evidence--caution {
  background: var(--color-evidence-caution-bg);
  border-color: var(--color-evidence-caution);
}
.evidence--caution h4 { color: #991b1b; margin-top: 0; }

/* Tables */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  font-size: 0.95rem;
  background: #ffffff;
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-border);
}
th {
  background: var(--color-dark);
  color: #ffffff;
  padding: 12px 14px;
  text-align: left;
}
td {
  padding: 12px 14px;
  border-bottom: 1px solid var(--color-border);
}
tr:nth-child(even) td {
  background-color: #f8fafc;
}

/* Contextual Product/Affiliate Recommendation Card */
.product-card {
  background: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin: 32px 0;
  box-shadow: var(--shadow-sm);
}
.product-card__tag {
  display: inline-block;
  background: #e0f2fe;
  color: #0369a1;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  padding: 4px 10px;
  border-radius: var(--radius-pill);
  margin-bottom: 12px;
}

/* CTA Buttons */
.btn-cta {
  display: inline-block;
  background: linear-gradient(135deg, #0284c7 0%, #0369a1 100%);
  color: #ffffff !important;
  font-weight: 700;
  font-size: 1.05rem;
  padding: 14px 28px;
  border-radius: var(--radius-md);
  text-decoration: none !important;
  transition: all 0.2s ease;
  box-shadow: 0 4px 12px rgba(2, 132, 199, 0.25);
  margin: 16px 0;
  text-align: center;
}
.btn-cta:hover {
  background: linear-gradient(135deg, #0369a1 0%, #075985 100%);
  color: #ffffff !important;
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(2, 132, 199, 0.35);
}

/* Editorial Image System */
.article-figure {
  margin: 32px 0;
  text-align: center;
}
.article-figure img {
  width: 100%;
  height: auto;
  max-width: 100%;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-md);
  object-fit: cover;
  display: block;
}
.article-figure figcaption {
  margin-top: 10px;
  font-size: 0.88rem;
  color: var(--color-text-muted);
  font-style: italic;
  line-height: 1.4;
}

/* FAQ Component */
.faq {
  margin: 32px 0;
}
.faq__item {
  background: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
}
.faq__q {
  padding: 16px 20px;
  font-weight: 700;
  color: var(--color-dark);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
}
.faq__a {
  padding: 0 20px 16px 20px;
  display: none;
}
.faq__item.is-open .faq__a { display: block; }

/* Related Grid */
.related-section {
  background: #f1f5f9;
  padding: 48px 0;
  border-top: 1px solid var(--color-border);
  margin-top: 60px;
}
.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
  margin-top: 20px;
}
.related-card {
  background: #ffffff;
  padding: 20px;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  text-decoration: none;
  transition: transform 0.2s ease;
}
.related-card:hover { transform: translateY(-3px); }
.related-card h4 { margin: 0 0 6px 0; color: var(--color-dark); }
.related-card span { font-size: 0.85rem; color: var(--color-primary); font-weight: 600; }

/* Footer */
.footer {
  background: var(--color-dark);
  color: #94a3b8;
  padding: 40px 0;
  text-align: center;
  font-size: 0.9rem;
}
.footer a { color: #cbd5e1; text-decoration: none; margin: 0 8px; }

@media (max-width: 768px) {
  h1 { font-size: 2rem; }
  h2 { font-size: 1.5rem; }
  .header .nav { display: none; }
}