/* ===========================================
   OPERON RESEARCH — DESIGN SYSTEM
   Shared styles across all pages.
   =========================================== */

:root {
  --deep-navy: #0F172A;
  --slate: #334155;
  --muted-teal: #1F7A74;
  --muted-amber: #C89B3C;
  --near-black: #0A0A0A;
  --mid-gray: #64748B;
  --light-gray: #CBD5E1;
  --bg: #F1F5F9;
  --white: #FFFFFF;
  --border: #E2E8F0;
}

@font-face {
  font-family: 'Inter';
  src: url('https://rsms.me/inter/font-files/Inter-Regular.woff2?v=4.0') format('woff2');
  font-weight: 400; font-style: normal;
}
@font-face {
  font-family: 'Inter';
  src: url('https://rsms.me/inter/font-files/Inter-Medium.woff2?v=4.0') format('woff2');
  font-weight: 500; font-style: normal;
}
@font-face {
  font-family: 'Inter';
  src: url('https://rsms.me/inter/font-files/Inter-SemiBold.woff2?v=4.0') format('woff2');
  font-weight: 600; font-style: normal;
}
@font-face {
  font-family: 'Inter';
  src: url('https://rsms.me/inter/font-files/Inter-Bold.woff2?v=4.0') format('woff2');
  font-weight: 700; font-style: normal;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  color: var(--near-black);
  background: var(--white);
  font-feature-settings: 'cv11', 'ss01', 'ss03';
  -webkit-font-smoothing: antialiased;
  line-height: 1.5;
}
a { color: inherit; text-decoration: none; }

/* ============ NAVIGATION ============ */
.nav-wrap {
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  z-index: 100;
  border-bottom: 1px solid var(--border);
}
nav {
  max-width: 1280px;
  margin: 0 auto;
  padding: 20px 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-logo { display: flex; align-items: center; gap: 12px; }
.nav-mark { height: 28px; width: auto; }
.nav-links { display: flex; gap: 36px; align-items: center; }
.nav-links a {
  font-size: 13px;
  font-weight: 500;
  color: var(--slate);
  transition: color 0.18s ease;
  letter-spacing: 0.01em;
  position: relative;
}
.nav-links a:hover { color: var(--deep-navy); }
.nav-links a.active { color: var(--deep-navy); }
.nav-links a.active::after {
  content: '';
  position: absolute;
  bottom: -22px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--muted-teal);
}
.nav-cta { display: flex; gap: 12px; align-items: center; }
.nav-login {
  font-size: 13px;
  font-weight: 500;
  color: var(--slate);
  transition: color 0.18s ease;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
}
.nav-login:hover { color: var(--deep-navy); }

/* Login Dropdown */
.login-dropdown {
  position: relative;
  display: inline-block;
}
.login-dropdown-menu {
  display: none;
  position: absolute;
  right: 0;
  top: calc(100% + 8px);
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 8px 0;
  min-width: 200px;
  box-shadow: 0 4px 12px rgba(15, 23, 42, 0.1);
  z-index: 1000;
}
/* Bridge the gap between button and menu */
.login-dropdown-menu::before {
  content: '';
  position: absolute;
  top: -8px;
  left: 0;
  right: 0;
  height: 8px;
}
.login-dropdown:hover .login-dropdown-menu,
.login-dropdown-menu:hover {
  display: block;
}
.login-dropdown-menu a {
  display: block;
  padding: 10px 16px;
  font-size: 13px;
  color: var(--slate);
  transition: background 0.15s ease, color 0.15s ease;
}
.login-dropdown-menu a:hover {
  background: var(--bg);
  color: var(--deep-navy);
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 20px;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.005em;
  transition: all 0.2s ease;
  cursor: pointer;
  border: 1px solid transparent;
}
.btn-primary {
  background: var(--deep-navy);
  color: var(--white);
}
.btn-primary:hover {
  background: #1e293b;
  transform: translateY(-1px);
}
.btn-secondary {
  background: transparent;
  color: var(--deep-navy);
  border-color: var(--light-gray);
}
.btn-secondary:hover { border-color: var(--deep-navy); }
.btn-on-dark {
  background: var(--white);
  color: var(--deep-navy);
  padding: 13px 24px;
  font-size: 14px;
}
.btn-on-dark:hover {
  background: #f1f5f9;
  transform: translateY(-1px);
}

.btn-link {
  color: var(--deep-navy);
  font-weight: 500;
  font-size: 14px;
  padding: 11px 4px;
  transition: color 0.18s;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
}
.btn-link:hover { color: var(--muted-teal); }
.btn-link::after {
  content: '→';
  transition: transform 0.2s ease;
}
.btn-link:hover::after { transform: translateX(3px); }

/* ============ TYPOGRAPHY ============ */
.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-size: 11px;
  font-weight: 500;
  color: var(--muted-teal);
}
.section-eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-size: 11px;
  font-weight: 500;
  color: var(--muted-teal);
  margin-bottom: 48px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}
.section-headline {
  font-size: 36px;
  font-weight: 600;
  letter-spacing: -0.015em;
  color: var(--deep-navy);
  margin-bottom: 32px;
  max-width: 760px;
  line-height: 1.15;
}

/* ============ PAGE SCAFFOLD ============ */
section.content {
  max-width: 1280px;
  margin: 0 auto;
  padding: 100px 48px;
}
section.content-narrow {
  max-width: 880px;
  margin: 0 auto;
  padding: 100px 48px;
}

/* ============ PAGE HERO ============ */
.page-hero {
  max-width: 1280px;
  margin: 0 auto;
  padding: 100px 48px 60px;
  border-bottom: 1px solid var(--border);
}
.page-hero .eyebrow { margin-bottom: 28px; display: block; }
.page-hero h1 {
  font-size: clamp(40px, 5vw, 60px);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.05;
  color: var(--deep-navy);
  margin-bottom: 28px;
  max-width: 920px;
}
.page-hero .subhead {
  font-size: 19px;
  color: var(--slate);
  max-width: 680px;
  line-height: 1.55;
}

/* ============ FOOTER ============ */
footer {
  background: var(--deep-navy);
  color: var(--light-gray);
  padding: 80px 48px 40px;
}
.footer-content {
  max-width: 1280px;
  margin: 0 auto;
}
.footer-disclosure {
  font-size: 13px;
  color: var(--mid-gray);
  margin-bottom: 56px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(203, 213, 225, 0.15);
  font-style: italic;
}
.footer-disclosure strong {
  color: var(--light-gray);
  font-weight: 500;
  font-style: normal;
}
.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 32px;
}
.footer-nav {
  display: flex;
  gap: 28px;
  flex-wrap: wrap;
}
.footer-nav a {
  font-size: 12px;
  color: var(--light-gray);
  font-weight: 500;
  transition: color 0.2s ease;
}
.footer-nav a:hover { color: var(--white); }
.footer-copyright {
  font-size: 12px;
  color: var(--mid-gray);
}

/* ============ COMMON ANIMATIONS ============ */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}
.fade-up {
  animation: fadeUp 0.7s ease-out forwards;
}
.delay-1 { animation-delay: 0.1s; opacity: 0; }
.delay-2 { animation-delay: 0.2s; opacity: 0; }
.delay-3 { animation-delay: 0.3s; opacity: 0; }
.delay-4 { animation-delay: 0.4s; opacity: 0; }

/* ============ RESPONSIVE BASE ============ */
@media (max-width: 900px) {
  nav { padding: 16px 24px; }
  .nav-links { display: none; }
  .page-hero { padding: 60px 24px 40px; }
  .page-hero h1 { font-size: 36px; }
  section.content, section.content-narrow { padding: 60px 24px; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
  footer { padding: 60px 24px 32px; }
}