/* ==========================================
   Vision & Neuroscience Research Website
   Plain CSS (RTF wrapper removed)
   ========================================== */

/* Base / Tokens */
:root {
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-serif: ui-serif, Georgia, "Times New Roman", serif;

  --bg: #f6f4ef;
  --surface: rgba(255, 255, 255, 0.82);
  --surface-solid: #ffffff;
  --text: #131a1f;
  --muted: rgba(19, 26, 31, 0.72);
  --hairline: rgba(19, 26, 31, 0.12);

  --brand: #143a5b;
  --brand-2: #1d5a7a;
  --accent: #c86b3c;

  --shadow-sm: 0 10px 24px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 18px 40px rgba(0, 0, 0, 0.14);

  --r-sm: 12px;
  --r-md: 16px;
  --r-lg: 22px;

  --space-1: 0.5rem;
  --space-2: 0.75rem;
  --space-3: 1rem;
  --space-4: 1.5rem;
  --space-5: 2rem;
  --space-6: 3rem;
  --space-7: 4rem;

  --container: 1120px;
  --ease: cubic-bezier(0.2, 0.8, 0.2, 1);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--text);
  line-height: 1.6;
  background:
    radial-gradient(1000px 560px at 15% 10%, rgba(29, 90, 122, 0.12), transparent 55%),
    radial-gradient(900px 520px at 85% 18%, rgba(200, 107, 60, 0.12), transparent 58%),
    linear-gradient(180deg, #fbfaf7 0%, var(--bg) 55%, #f3f1ea 100%);
}

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

.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--space-5);
}

/* Typography */
h1, h2, h3, h4 {
  margin: 0 0 var(--space-3);
  line-height: 1.15;
  letter-spacing: -0.02em;
}

h1 {
  font-size: clamp(1.6rem, 2.4vw, 2.3rem);
}

h2 {
  font-size: clamp(1.45rem, 2.2vw, 2.05rem);
}

h3 {
  font-size: 1.25rem;
}

p {
  margin: 0 0 var(--space-3);
  color: var(--muted);
}

.lead {
  font-size: clamp(1.05rem, 1.2vw, 1.2rem);
  line-height: 1.8;
}

a {
  color: var(--brand-2);
  text-decoration: none;
  text-underline-offset: 0.2em;
}

a:hover {
  color: var(--accent);
  text-decoration: underline;
}

::selection {
  background: rgba(200, 107, 60, 0.25);
}

/* Focus */
:focus-visible {
  outline: 3px solid rgba(200, 107, 60, 0.55);
  outline-offset: 3px;
  border-radius: 10px;
}

/* Navigation */
.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  background: rgba(251, 250, 247, 0.72);
  border-bottom: 1px solid rgba(19, 26, 31, 0.08);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-3) var(--space-5);
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.nav-brand h1 {
  margin: 0;
  font-size: 1.05rem;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: rgba(19, 26, 31, 0.82);
}

.nav-menu {
  list-style: none;
  display: flex;
  gap: var(--space-2);
  padding: 0;
  margin: 0;
}

.nav-menu a {
  display: inline-flex;
  align-items: center;
  height: 38px;
  padding: 0 14px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  color: rgba(19, 26, 31, 0.78);
  text-decoration: none;
  transition: transform 140ms var(--ease), background 140ms var(--ease), color 140ms var(--ease);
}

.nav-menu a:hover {
  background: rgba(29, 90, 122, 0.12);
  color: var(--text);
  transform: translateY(-1px);
}

.nav-menu a.active {
  background: rgba(20, 58, 91, 0.16);
  color: var(--text);
}

/* Hero */
.hero {
  padding: var(--space-7) 0 var(--space-6);
}

.hero .container {
  position: relative;
}

.hero-content {
  max-width: 920px;
  margin: 0 auto;
  padding: var(--space-6);
  border-radius: var(--r-lg);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.86) 0%, rgba(255, 255, 255, 0.72) 100%);
  border: 1px solid rgba(19, 26, 31, 0.08);
  box-shadow: var(--shadow-md);
}

.hero-content h2 {
  font-family: var(--font-serif);
  color: var(--text);
  font-weight: 700;
  margin-bottom: var(--space-3);
}

.hero-content .lead {
  max-width: 75ch;
  margin: 0;
}

/* Introduction */
.introduction {
  padding: var(--space-6) 0;
}

.intro-text {
  max-width: 900px;
  margin: 0 auto;
  padding: var(--space-5);
  border-radius: var(--r-md);
  background: rgba(255, 255, 255, 0.66);
  border: 1px solid rgba(19, 26, 31, 0.08);
  box-shadow: var(--shadow-sm);
}

.intro-text p {
  margin-bottom: var(--space-4);
}

/* Research categories */
.research-categories {
  padding: var(--space-6) 0 var(--space-7);
}

.section-title {
  text-align: center;
  font-family: var(--font-serif);
  letter-spacing: -0.01em;
  color: rgba(19, 26, 31, 0.9);
}

.categories-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-4);
  margin-top: var(--space-5);
}

.category-card {
  position: relative;
  display: block;
  padding: var(--space-5);
  border-radius: var(--r-lg);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.9) 0%, rgba(255, 255, 255, 0.72) 100%);
  border: 1px solid rgba(19, 26, 31, 0.08);
  box-shadow: var(--shadow-sm);
  transition: transform 220ms var(--ease), box-shadow 220ms var(--ease), border-color 220ms var(--ease);
}

.category-card::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background:
    radial-gradient(380px 180px at 15% 15%, rgba(29, 90, 122, 0.16), transparent 65%),
    radial-gradient(260px 160px at 85% 10%, rgba(200, 107, 60, 0.18), transparent 65%);
  opacity: 0;
  transition: opacity 220ms var(--ease);
  pointer-events: none;
}

.category-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: rgba(29, 90, 122, 0.22);
}

.category-card:hover::before {
  opacity: 1;
}

.category-card h3 {
  margin: 0;
  color: rgba(19, 26, 31, 0.92);
  font-weight: 750;
  letter-spacing: -0.01em;
  text-align: center;
}

.category-card p {
  margin-top: var(--space-2);
  text-align: center;
}

.read-more {
  display: block;
  margin-top: var(--space-3);
  text-align: center;
  font-weight: 650;
}

/* Breadcrumb */
.breadcrumb {
  padding: var(--space-3) 0;
  border-bottom: 1px solid rgba(19, 26, 31, 0.08);
  background: rgba(255, 255, 255, 0.5);
}

.breadcrumb .container {
  font-size: 0.95rem;
  color: rgba(19, 26, 31, 0.65);
}

.breadcrumb a {
  color: rgba(19, 26, 31, 0.78);
}

.breadcrumb a:hover {
  color: var(--accent);
}

/* Category header */
.category-header {
  padding: var(--space-7) 0 var(--space-6);
}

.category-header-content {
  max-width: 980px;
  margin: 0 auto;
  padding: var(--space-6);
  border-radius: var(--r-lg);
  background: linear-gradient(180deg, rgba(20, 58, 91, 0.92) 0%, rgba(29, 90, 122, 0.86) 100%);
  border: 1px solid rgba(255, 255, 255, 0.16);
  box-shadow: var(--shadow-md);
}

.category-header-text h1 {
  color: rgba(255, 255, 255, 0.96);
  margin-bottom: var(--space-2);
  font-family: var(--font-serif);
}

.category-description {
  color: rgba(255, 255, 255, 0.88);
  font-size: 1.05rem;
  line-height: 1.8;
  margin: 0;
}

/* Publications */
.publications-section {
  padding: var(--space-6) 0 var(--space-7);
}

.publications-list {
  max-width: 980px;
  margin: 0 auto;
}

.publication-item {
  display: flex;
  gap: var(--space-4);
  padding: var(--space-5);
  margin-bottom: var(--space-4);
  border-radius: var(--r-md);
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid rgba(19, 26, 31, 0.08);
  box-shadow: var(--shadow-sm);
  transition: transform 220ms var(--ease), box-shadow 220ms var(--ease);
}

.publication-item:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.pub-year {
  flex: 0 0 auto;
  min-width: 5ch;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: rgba(20, 58, 91, 0.92);
}

.pub-content {
  flex: 1;
}

.pub-title {
  margin: 0 0 var(--space-2);
  color: rgba(19, 26, 31, 0.94);
  font-weight: 750;
}

.pub-authors,
.pub-journal {
  margin: 0 0 var(--space-2);
}

.pub-journal {
  font-style: italic;
}

.pub-links {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: var(--space-2);
}

.pub-link {
  display: inline-flex;
  align-items: center;
  height: 36px;
  padding: 0 14px;
  border-radius: 999px;
  background: rgba(29, 90, 122, 0.12);
  border: 1px solid rgba(29, 90, 122, 0.16);
  color: rgba(19, 26, 31, 0.86);
  font-weight: 650;
  text-decoration: none;
  transition: transform 160ms var(--ease), background 160ms var(--ease), border-color 160ms var(--ease);
}

.pub-link:hover {
  transform: translateY(-1px);
  background: rgba(200, 107, 60, 0.18);
  border-color: rgba(200, 107, 60, 0.28);
  color: rgba(19, 26, 31, 0.92);
  text-decoration: none;
}

.pub-link.secondary {
  background: transparent;
  border: 1px solid rgba(29, 90, 122, 0.35);
}

/* Back section */
.back-section {
  padding: var(--space-6) 0;
}

.btn-back {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 44px;
  padding: 0 18px;
  border-radius: 999px;
  background: rgba(20, 58, 91, 0.92);
  color: rgba(255, 255, 255, 0.96);
  font-weight: 700;
  text-decoration: none;
  box-shadow: var(--shadow-sm);
  transition: transform 160ms var(--ease), filter 160ms var(--ease);
}

.btn-back:hover {
  transform: translateY(-1px);
  filter: brightness(1.06);
  text-decoration: none;
  color: rgba(255, 255, 255, 0.96);
}

/* Contact page */
.page-header {
  padding: var(--space-6) 0 var(--space-4);
  text-align: center;
}

.page-header h1 {
  font-family: var(--font-serif);
  color: rgba(19, 26, 31, 0.92);
}

.page-subtitle {
  margin: 0 auto;
  max-width: 70ch;
}

.contact-section {
  padding: var(--space-6) 0 var(--space-7);
}

.contact-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: var(--space-6);
  align-items: start;
}

.contact-info,
.contact-form-wrapper {
  padding: var(--space-5);
  border-radius: var(--r-lg);
  background: rgba(255, 255, 255, 0.76);
  border: 1px solid rgba(19, 26, 31, 0.08);
  box-shadow: var(--shadow-sm);
}

.contact-info h2,
.contact-form-wrapper h2 {
  margin-bottom: var(--space-4);
  font-family: var(--font-serif);
}

.info-item {
  margin-bottom: var(--space-4);
}

.info-item h3 {
  margin: 0 0 var(--space-2);
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: rgba(19, 26, 31, 0.62);
}

/* Form (if present on contact page) */
.contact-form {
  background: rgba(19, 26, 31, 0.04);
  padding: var(--space-4);
  border-radius: var(--r-md);
  border: 1px solid rgba(19, 26, 31, 0.08);
}

.form-group {
  margin-bottom: var(--space-3);
}

.form-group label {
  display: block;
  margin: 0 0 var(--space-1);
  font-weight: 650;
  color: rgba(19, 26, 31, 0.84);
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 12px 12px;
  border-radius: 12px;
  border: 1px solid rgba(19, 26, 31, 0.16);
  background: rgba(255, 255, 255, 0.9);
  color: var(--text);
  font: inherit;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: rgba(200, 107, 60, 0.55);
  box-shadow: 0 0 0 4px rgba(200, 107, 60, 0.15);
}

.btn-submit {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 44px;
  padding: 0 18px;
  border: 0;
  border-radius: 999px;
  cursor: pointer;
  background: rgba(200, 107, 60, 0.92);
  color: rgba(255, 255, 255, 0.96);
  font-weight: 750;
  transition: transform 160ms var(--ease), filter 160ms var(--ease);
}

.btn-submit:hover {
  transform: translateY(-1px);
  filter: brightness(1.06);
}

/* JS features */
.scroll-to-top {
  position: fixed;
  right: 18px;
  bottom: 18px;
  width: 48px;
  height: 48px;
  border-radius: 999px;
  border: 1px solid rgba(19, 26, 31, 0.12);
  background: rgba(255, 255, 255, 0.86);
  color: rgba(19, 26, 31, 0.9);
  box-shadow: var(--shadow-sm);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity 180ms var(--ease), transform 180ms var(--ease), visibility 180ms var(--ease);
  z-index: 999;
}

.scroll-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.search-container {
  max-width: 980px;
  margin: 0 auto var(--space-5);
}

.publication-search-input {
  width: 100%;
  padding: 14px 14px;
  border-radius: var(--r-md);
  border: 1px solid rgba(19, 26, 31, 0.16);
  background: rgba(255, 255, 255, 0.86);
  font: inherit;
}

.publication-search-input:focus {
  outline: none;
  border-color: rgba(200, 107, 60, 0.55);
  box-shadow: 0 0 0 4px rgba(200, 107, 60, 0.15);
}

.publication-count {
  text-align: center;
  color: rgba(19, 26, 31, 0.66);
}

.mobile-menu-toggle {
  display: none;
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid rgba(19, 26, 31, 0.12);
  border-radius: 12px;
  padding: 10px 12px;
  font: inherit;
  cursor: pointer;
}

.external-icon {
  opacity: 0.65;
}

/* Footer */
footer {
  padding: var(--space-6) 0;
  border-top: 1px solid rgba(19, 26, 31, 0.08);
  background: rgba(255, 255, 255, 0.5);
}

footer p {
  margin: 0;
  text-align: center;
  color: rgba(19, 26, 31, 0.62);
}

/* Responsive */
@media (max-width: 968px) {
  .contact-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .container {
    padding: 0 var(--space-4);
  }

  .navbar .container {
    position: relative;
    flex-wrap: wrap;
  }

  .mobile-menu-toggle {
    display: inline-flex;
  }

  .nav-menu {
    width: 100%;
    justify-content: center;
    flex-wrap: wrap;
    padding-bottom: var(--space-2);
  }

  .nav-menu.mobile-hidden {
    display: none;
  }

  .hero-content {
    padding: var(--space-5);
  }

  .category-header-content {
    padding: var(--space-5);
  }

  .publication-item {
    flex-direction: column;
  }
}

@media (prefers-reduced-motion: reduce) {
  * {
    transition: none !important;
    scroll-behavior: auto !important;
  }
}

/* Print */
@media print {
  .navbar,
  .back-section,
  .scroll-to-top {
    display: none !important;
  }

  body {
    background: #fff;
  }

  .publication-item {
    box-shadow: none;
  }
}