/* ============================================
   BPS AI Industry Advisory Board
   bostonpublic.ai — Shared Stylesheet
   ============================================ */

/* --- Google Fonts --- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&display=swap');

/* --- CSS Variables --- */
:root {
  --navy:      #0F2A4A;
  --blue:      #1D4ED8;
  --blue-dark: #1740B0;
  --gold:      #C9A84C;
  --white:     #FFFFFF;
  --gray-light:#F5F7FA;
  --gray-mid:  #E2E8F0;
  --gray-text: #64748B;
  --gray-dark: #374151;
  --black:     #0A0A0A;
  --font:      'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --max-w:     1200px;
  --transition: 0.25s ease;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.10);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.12);
}

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

html {
  scroll-behavior: smooth;
  font-size: 17px;
}

body {
  font-family: var(--font);
  color: var(--navy);
  background: var(--white);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

img { display: block; max-width: 100%; height: auto; }
a { color: var(--blue); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--blue-dark); }

/* --- Typography --- */
h1, h2, h3, h4, h5 {
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--navy);
}

h1 { font-size: clamp(2.4rem, 5vw, 4rem); }
h2 { font-size: clamp(1.8rem, 3.5vw, 2.75rem); }
h3 { font-size: clamp(1.3rem, 2.5vw, 1.75rem); }
h4 { font-size: 1.15rem; }

/* --- Layout --- */
.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
}

section { padding: 96px 0; }

/* ============================================
   NAVIGATION
   ============================================ */
#nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  background: rgba(15, 42, 74, 0.97);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(255,255,255,0.08);
  transition: box-shadow var(--transition);
}

#nav.scrolled {
  box-shadow: 0 2px 24px rgba(0,0,0,0.3);
}

.nav-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
  height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--white);
  letter-spacing: -0.02em;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-logo:hover { color: var(--white); opacity: 0.9; }

.nav-logo-dot {
  width: 8px; height: 8px;
  background: var(--blue);
  border-radius: 50%;
  flex-shrink: 0;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  list-style: none;
}

.nav-links a {
  color: rgba(255,255,255,0.75);
  font-size: 0.9rem;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: 6px;
  transition: all var(--transition);
  text-decoration: none;
}

.nav-links a:hover { color: var(--white); background: rgba(255,255,255,0.08); }
.nav-links a.active { color: var(--gold); background: rgba(201,168,76,0.1); }

.nav-cta {
  background: var(--blue) !important;
  color: var(--white) !important;
  padding: 9px 18px !important;
  border-radius: 8px !important;
  font-weight: 600 !important;
  font-size: 0.875rem !important;
  letter-spacing: 0.01em;
}

.nav-cta:hover { background: var(--blue-dark) !important; opacity: 1 !important; }
.nav-cta.active { background: var(--gold) !important; color: var(--navy) !important; }

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 6px;
  border: none;
  background: none;
}

.hamburger span {
  display: block;
  width: 22px; height: 2px;
  background: var(--white);
  border-radius: 2px;
  transition: all 0.3s ease;
}

.hamburger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.open span:nth-child(2) { opacity: 0; }
.hamburger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* Mobile nav overlay */
.mobile-nav {
  display: none;
  position: fixed;
  inset: 68px 0 0;
  background: var(--navy);
  z-index: 999;
  padding: 24px;
  flex-direction: column;
  gap: 4px;
}

.mobile-nav.open { display: flex; }

.mobile-nav a {
  color: rgba(255,255,255,0.8);
  font-size: 1.1rem;
  font-weight: 500;
  padding: 14px 16px;
  border-radius: 8px;
  text-decoration: none;
  border-bottom: 1px solid rgba(255,255,255,0.06);
  transition: all var(--transition);
}

.mobile-nav a:hover { color: var(--white); background: rgba(255,255,255,0.05); }
.mobile-nav a.active { color: var(--gold); background: rgba(201,168,76,0.1); }

.mobile-nav .nav-cta {
  margin-top: 16px;
  background: var(--blue) !important;
  text-align: center;
  padding: 14px !important;
  color: var(--white) !important;
}

/* ============================================
   BUTTONS
   ============================================ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font);
  font-size: 0.95rem;
  font-weight: 600;
  padding: 14px 28px;
  border-radius: 10px;
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
  border: none;
  letter-spacing: 0.01em;
}

.btn-primary {
  background: var(--blue);
  color: var(--white);
  box-shadow: 0 0 0 0 rgba(29, 78, 216, 0.4);
}

.btn-primary:hover {
  background: var(--blue-dark);
  color: var(--white);
  transform: translateY(-1px);
  box-shadow: 0 8px 24px rgba(29, 78, 216, 0.35);
}

.btn-secondary {
  background: transparent;
  color: var(--white);
  border: 1.5px solid rgba(255,255,255,0.5);
}

.btn-secondary:hover {
  background: rgba(255,255,255,0.1);
  color: var(--white);
  border-color: rgba(255,255,255,0.8);
}

.btn-outline {
  background: transparent;
  color: var(--blue);
  border: 1.5px solid var(--blue);
}

.btn-outline:hover {
  background: var(--blue);
  color: var(--white);
}

/* ============================================
   PAGE HERO (inner pages)
   ============================================ */
.page-hero {
  position: relative;
  height: 380px;
  display: flex;
  align-items: flex-end;
  overflow: hidden;
  margin-top: 68px;
}

.page-hero-bg {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
}

.page-hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, rgba(15,42,74,0.92) 0%, rgba(15,42,74,0.55) 60%, rgba(15,42,74,0.3) 100%);
}

.page-hero-content {
  position: relative;
  z-index: 1;
  padding: 0 24px 52px;
  max-width: var(--max-w);
  width: 100%;
  margin: 0 auto;
}

.page-hero-content h1 {
  color: var(--white);
  font-size: clamp(2.2rem, 4.5vw, 3.5rem);
}

.page-hero--tall {
  height: 560px;
}

.page-hero--tall .page-hero-overlay {
  background: linear-gradient(to top, rgba(15,42,74,0.88) 0%, rgba(15,42,74,0.6) 50%, rgba(15,42,74,0.35) 100%);
}

.page-hero--tall .page-hero-content {
  padding-bottom: 64px;
}

.page-hero-tagline {
  color: rgba(255,255,255,0.85);
  font-size: clamp(1rem, 1.8vw, 1.15rem);
  line-height: 1.6;
  margin-top: 18px;
  max-width: none;
}

/* ============================================
   PLACEHOLDERS (for images not yet sourced)
   ============================================ */
.img-placeholder {
  background: linear-gradient(135deg, #1a3a5c 0%, #0a1e35 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255,255,255,0.2);
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  width: 100%;
  height: 100%;
}

/* ============================================
   SECTION LABELS
   ============================================ */
.section-label {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--blue);
  margin-bottom: 16px;
}

/* ============================================
   QUOTES
   ============================================ */
.pullquote {
  position: relative;
  padding: 48px 0;
}

.pullquote blockquote {
  font-size: clamp(1.3rem, 2.5vw, 1.8rem);
  font-weight: 600;
  line-height: 1.45;
  color: var(--navy);
  max-width: 800px;
  letter-spacing: -0.01em;
}

.pullquote blockquote::before {
  content: '\201C';
  font-size: 5rem;
  color: var(--blue);
  line-height: 0.6;
  display: block;
  margin-bottom: 16px;
  font-weight: 800;
}

.pullquote cite {
  display: block;
  margin-top: 24px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--gray-text);
  font-style: normal;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* ============================================
   FOOTER
   ============================================ */
footer {
  background: var(--navy);
  color: var(--white);
  padding: 72px 0 40px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1.5fr;
  gap: 56px;
  padding-bottom: 28px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
  margin-bottom: 24px;
}

.footer-logo {
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--white);
  letter-spacing: -0.02em;
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 16px;
}

.footer-tagline {
  color: rgba(255,255,255,0.6);
  font-size: 0.9rem;
  line-height: 1.65;
  max-width: 30ch;
}

.footer-col h5 {
  color: rgba(255,255,255,0.45);
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 20px;
  color: rgba(255,255,255,0.5);
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a {
  color: rgba(255,255,255,0.7);
  font-size: 0.9rem;
  font-weight: 500;
  text-decoration: none;
  transition: color var(--transition);
}

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

.footer-contact-item {
  color: rgba(255,255,255,0.7);
  font-size: 0.9rem;
  margin-bottom: 10px;
}

.footer-contact-item a { color: rgba(255,255,255,0.7); }
.footer-contact-item a:hover { color: var(--white); }

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.footer-copy {
  color: rgba(255,255,255,0.4);
  font-size: 0.8rem;
}

.footer-legal-links {
  display: flex;
  gap: 20px;
  align-items: center;
}

.footer-legal-links a {
  color: rgba(255,255,255,0.4);
  font-size: 0.8rem;
  text-decoration: none;
  transition: color var(--transition);
}

.footer-legal-links a:hover { color: rgba(255,255,255,0.75); }

.footer-photo-credit {
  width: 100%;
  color: rgba(255,255,255,0.3);
  font-size: 0.75rem;
  margin-top: 8px;
}

/* ============================================
   RESPONSIVE
   ============================================ */
@media (max-width: 768px) {
  section { padding: 64px 0; }

  .nav-links { display: none; }
  .hamburger { display: flex; }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
  }

  /* Regular heroes shrink; tall heroes grow to fit content instead */
  .page-hero:not(.page-hero--tall) { height: 280px; }

  .page-hero--tall {
    height: auto;
    min-height: 380px;
    align-items: flex-start;
  }

  .page-hero--tall .page-hero-content {
    padding-top: 100px;
    padding-bottom: 48px;
  }
}

/* ============================================
   ANIMATIONS
   ============================================ */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(24px); }
  to   { opacity: 1; transform: translateY(0); }
}

.fade-up {
  opacity: 0;
  animation: fadeUp 0.65s ease forwards;
}

.fade-up-1 { animation-delay: 0.1s; }
.fade-up-2 { animation-delay: 0.2s; }
.fade-up-3 { animation-delay: 0.3s; }
.fade-up-4 { animation-delay: 0.4s; }