site.css

/* ═══════════════════════════════════════════════════════════
   Active Inference Institute — Shared Styles
   All pages include this file for consistent design tokens,
   header, footer, navigation, and common components.
   ═══════════════════════════════════════════════════════════ */

/* ═══ RESET & TOKENS ═══ */
* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
  --black: #0a0a0a;
  --deep: #141210;
  --charcoal: #1c1a18;
  --white: #faf9f8;
  --grey-dark: #1a1918;
  --grey-mid: #5a5856;
  --grey-light: #8a8886;
  --grey-pale: #f5f4f2;
  --grey-border: #e8e6e4;
  --accent: #c54a2a;
  --accent-deep: #b33d20;
  --accent-light: #d4593a;
  --accent-subtle: rgba(197, 74, 42, 0.08);
  --gold: #c9a227;
}

::selection { background: var(--accent); color: var(--white); }
@media (prefers-reduced-motion: no-preference) { html { scroll-behavior: smooth; } }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }
[id] { scroll-margin-top: 88px; }

body {
  font-family: Georgia, 'Times New Roman', Times, serif;
  color: var(--grey-dark);
  line-height: 1.7;
  background: var(--white);
}

/* ═══ SKIP LINK ═══ */
.skip-link {
  position: absolute; top: -100px; left: 16px;
  background: var(--accent); color: var(--white);
  padding: 10px 18px; z-index: 2000; text-decoration: none;
  font-family: Georgia, 'Times New Roman', serif; font-size: 13px;
  transition: top 0.2s ease;
}
.skip-link:focus { top: 12px; }

/* ═══ HEADER ═══ */
.header {
  background: var(--black);
  position: fixed; top: 0; left: 0; right: 0;
  z-index: 1000;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
.header-inner {
  max-width: 1400px; margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  height: 72px; padding: 0 40px;
}
.logo-container canvas { display: block; }
.logo-container a { text-decoration: none; }

.nav-links { display: flex; gap: 0; align-items: center; }

.nav-item {
  position: relative; padding: 0 18px; height: 72px;
  display: flex; align-items: center;
}
.nav-item > a, .nav-item > button {
  color: rgba(255,255,255,0.55); text-decoration: none; font-size: 13px;
  transition: color 0.3s ease; font-family: Georgia, 'Times New Roman', serif;
  letter-spacing: 0.5px; background: none; border: none; cursor: pointer;
  display: flex; align-items: center; gap: 5px; padding: 0;
}
.nav-item > a:hover, .nav-item > button:hover,
.nav-item.active > a, .nav-item.active > button { color: var(--white); }

.nav-chevron {
  width: 8px; height: 8px;
  border-right: 1.5px solid currentColor; border-bottom: 1.5px solid currentColor;
  transform: rotate(45deg) translateY(-2px); transition: transform 0.25s ease;
  flex-shrink: 0;
}
.nav-item.active .nav-chevron { transform: rotate(-135deg) translateY(-2px); }

.nav-cta-wrap { margin-left: 18px; }
.nav-cta {
  background: var(--accent); color: var(--white) !important;
  padding: 10px 24px; font-weight: 500; text-decoration: none;
  font-size: 13px; font-family: Georgia, 'Times New Roman', serif;
  letter-spacing: 0.5px; transition: background 0.3s ease;
}
.nav-cta:hover { background: var(--accent-light); }

/* ═══ MEGA MENU (full-width panel) ═══ */
.mega-menu {
  position: fixed;
  top: 72px;
  left: 0;
  right: 0;
  background: var(--white);
  border-top: 3px solid var(--accent);
  border-bottom: 1px solid var(--grey-border);
  box-shadow: 0 20px 60px rgba(0,0,0,0.12), 0 4px 16px rgba(0,0,0,0.08);
  padding: 44px 40px 40px;
  display: none;
  z-index: 999;
}
.nav-item.active .mega-menu {
  display: block;
  animation: megaReveal 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes megaReveal {
  from { opacity: 0; transform: translateY(-8px); }
  to { opacity: 1; transform: translateY(0); }
}

.mega-menu-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
  max-width: 1100px;
  margin: 0 auto;
}

.mega-menu-col h4 {
  font-size: 11px; text-transform: uppercase; letter-spacing: 2px;
  color: var(--accent-deep); margin-bottom: 20px;
  font-family: Georgia, 'Times New Roman', serif;
  padding-bottom: 12px; border-bottom: 1px solid var(--grey-border);
}
.mega-menu-col ul { list-style: none; }
.mega-menu-col li { margin-bottom: 4px; }
.mega-menu-col a {
  color: var(--grey-dark); text-decoration: none; font-size: 14px;
  font-family: Georgia, 'Times New Roman', serif;
  display: block; padding: 8px 12px; margin: 0 -12px;
  transition: all 0.2s ease; line-height: 1.4;
}
.mega-menu-col a:hover { background: var(--accent-subtle); color: var(--accent-deep); }
.mega-menu-col a .menu-desc {
  display: block; font-size: 12px; color: var(--grey-light);
  margin-top: 2px; line-height: 1.5;
}
.mega-menu-col a:hover .menu-desc { color: var(--grey-mid); }

.mega-menu-overlay {
  display: none; position: fixed; top: 72px; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.2); z-index: 998;
  backdrop-filter: blur(2px); -webkit-backdrop-filter: blur(2px);
}
.mega-menu-overlay.active { display: block; }

/* ═══ MOBILE NAV ═══ */
.mobile-menu-btn {
  display: none; background: transparent; border: none;
  cursor: pointer; padding: 8px; z-index: 1001;
}
.mobile-menu-btn span {
  display: block; width: 24px; height: 2px;
  background: var(--white); margin: 5px 0; transition: all 0.3s ease;
}
.mobile-menu-btn.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.mobile-menu-btn.active span:nth-child(2) { opacity: 0; }
.mobile-menu-btn.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

.mobile-nav {
  display: none; position: fixed; top: 60px; left: 0; right: 0; bottom: 0;
  background: var(--black); padding: 20px; z-index: 999; overflow-y: auto;
}
.mobile-nav.active { display: block; }
.mobile-nav-section { border-bottom: 1px solid rgba(255,255,255,0.1); padding: 16px 0; }
.mobile-nav-section:last-child { border-bottom: none; }
.mobile-nav-toggle {
  display: flex; justify-content: space-between; align-items: center;
  color: rgba(255,255,255,0.85); font-family: Georgia, 'Times New Roman', serif;
  font-size: 15px; background: none; border: none; cursor: pointer;
  width: 100%; padding: 8px 0; text-align: left;
}
.mobile-nav-toggle .mobile-chevron {
  width: 8px; height: 8px;
  border-right: 1.5px solid currentColor; border-bottom: 1.5px solid currentColor;
  transform: rotate(45deg); transition: transform 0.25s ease;
}
.mobile-nav-toggle.open .mobile-chevron { transform: rotate(-135deg); }
.mobile-nav-section > a {
  display: block; color: rgba(255,255,255,0.7); text-decoration: none;
  font-family: Georgia, 'Times New Roman', serif; font-size: 15px; padding: 8px 0;
}
.mobile-subnav { display: none; padding-left: 16px; padding-top: 8px; }
.mobile-subnav.open { display: block; }
.mobile-subnav-label {
  font-size: 10px; text-transform: uppercase; letter-spacing: 1.5px;
  color: var(--accent-light); margin: 12px 0 6px;
  font-family: Georgia, 'Times New Roman', serif;
}
.mobile-subnav a {
  display: block; font-size: 14px; padding: 6px 0;
  color: rgba(255,255,255,0.55); text-decoration: none;
  font-family: Georgia, 'Times New Roman', serif;
}
.mobile-subnav a:hover { color: var(--white); }
.mobile-nav-cta {
  display: block; background: var(--accent); color: var(--white) !important;
  text-align: center; padding: 14px; margin-top: 16px; text-decoration: none;
  font-family: Georgia, 'Times New Roman', serif; font-size: 15px;
}

@media (max-width: 900px) {
  .mobile-menu-btn { display: block; }
  .nav-links { display: none; }
  .header-inner { padding: 0 16px; height: 60px; }
  .mega-menu { top: 60px; }
  .mega-menu-overlay { top: 60px; }
}

/* ═══ BUTTONS ═══ */
.btn {
  padding: 15px 34px; font-size: 14px; text-decoration: none;
  transition: all 0.3s ease; display: inline-block;
  font-family: Georgia, 'Times New Roman', serif; letter-spacing: 0.5px; position: relative;
}
.btn-primary { background: var(--accent); color: var(--white); }
.btn-primary:hover { background: var(--accent-light); transform: translateY(-1px); box-shadow: 0 4px 12px rgba(197,74,42,0.3); }
.btn-outline {
  border: 1px solid rgba(255,255,255,0.3); color: var(--white);
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}
.btn-outline:hover { background: rgba(255,255,255,0.05); border-color: rgba(255,255,255,0.5); }

/* ═══ COMMON SECTIONS ═══ */
.section { padding: 100px 40px; }
.section-inner { max-width: 1100px; margin: 0 auto; }
.section-header { margin-bottom: 60px; text-align: center; }
.section-label {
  font-size: 12px; text-transform: uppercase; letter-spacing: 3px;
  color: var(--accent-deep); margin-bottom: 18px;
  font-family: Georgia, 'Times New Roman', serif;
}
.section-header h2 { font-size: 2.5rem; font-weight: 400; color: var(--grey-dark); }

/* ═══ PAGE HERO (subpages) ═══ */
.page-hero {
  background: var(--black); padding: 160px 40px 80px; text-align: center;
}
.page-hero h1 {
  font-size: clamp(2rem, 4vw, 2.8rem); font-weight: 400;
  color: var(--white); margin-bottom: 20px;
}
.page-hero p {
  font-size: 1.15rem; color: rgba(255,255,255,0.6);
  max-width: 650px; margin: 0 auto; line-height: 1.8;
}

/* ═══ FOOTER ═══ */
.footer {
  background: linear-gradient(to bottom, var(--charcoal) 0%, var(--black) 100%);
  color: var(--white); padding: 60px 40px 30px;
}
.footer-inner { max-width: 1100px; margin: 0 auto; }
.footer-grid {
  display: grid; grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 50px; margin-bottom: 50px;
}
.footer-brand p {
  color: rgba(255,255,255,0.5); margin-top: 20px;
  font-size: 13px; line-height: 1.8;
}
.footer-col h4 {
  font-size: 11px; text-transform: uppercase; letter-spacing: 1.5px;
  margin-bottom: 20px; color: var(--white);
  font-family: Georgia, 'Times New Roman', serif;
}
.footer-col ul { list-style: none; }
.footer-col li { margin-bottom: 10px; }
.footer-col a {
  color: rgba(255,255,255,0.5); text-decoration: none;
  font-size: 13px; transition: color 0.2s;
}
.footer-col a:hover { color: var(--white); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1); padding-top: 30px;
  display: flex; justify-content: space-between; align-items: center;
}
.footer-bottom p {
  color: rgba(255,255,255,0.35); font-size: 12px;
  font-family: Georgia, 'Times New Roman', serif; letter-spacing: 0.3px;
}
.social-links { display: flex; gap: 20px; align-items: center; }
.social-links a {
  color: rgba(255,255,255,0.4); text-decoration: none; font-size: 11px;
  transition: all 0.2s; font-family: Georgia, 'Times New Roman', serif;
  letter-spacing: 0.3px; display: flex; align-items: center; gap: 6px;
}
.social-links a:hover { color: var(--white); }
.social-links a:hover svg { opacity: 1; }
.social-links svg { width: 16px; height: 16px; opacity: 0.5; transition: opacity 0.2s; }

/* ═══ RESPONSIVE (shared) ═══ */
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  .section { padding: 60px 20px; }
  .section-header h2 { font-size: 1.8rem; }
  .page-hero { padding: 120px 20px 60px; }
  .footer { padding: 40px 20px 24px; }
  .footer-grid { grid-template-columns: 1fr; gap: 30px; }
  .footer-bottom { flex-direction: column; gap: 16px; text-align: center; }
}