:root {
  --primary-color: #212121;
  --accent-color: #4FC3F7;
  --bg-light: #FAFAFA;
  --bg-dark: #1A237E;
  --text-primary: #212121;
  --text-secondary: #757575;
  --text-light: #FFFFFF;
  --border-color: #E0E0E0;
  --font-heading: 'Lato', sans-serif;
  --font-body: 'Merriweather', serif;
  --spacing-xs: 4px;
  --spacing-s: 8px;
  --spacing-m: 16px;
  --spacing-l: 24px;
  --spacing-xl: 32px;
  --spacing-xxl: 64px;
  --spacing-xxxl: 80px;
  --border-radius: 8px;
  --shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
}

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

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

body {
  font-family: var(--font-body);
  color: var(--text-primary);
  line-height: 1.7;
  background-color: #FFFFFF;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--spacing-l);
}

h1 { font-size: clamp(2.5rem, 5vw, 4rem); font-weight: 900; }
h2 { font-size: clamp(2rem, 4vw, 3rem); }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

p { margin-bottom: var(--spacing-m); }
a { color: var(--accent-color); text-decoration: none; transition: color 0.3s ease; }
a:hover, a:focus { color: var(--primary-color); }
ul, ol { list-style-position: inside; padding-left: var(--spacing-m); margin-bottom: var(--spacing-m); }
img { max-width: 100%; height: auto; display: block; border-radius: var(--border-radius); }

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-l);
}

.text-center { text-align: center; }
.bg-light { background-color: var(--bg-light); }
.max-width-large { max-width: 900px; margin-left: auto; margin-right: auto; }
.text-center-prose { text-align: left; }
.text-center-prose > p { text-align: center; }


/* --- HEADER & NAVIGATION --- */
.main-header {
  position: sticky;
  top: 0;
  width: 100%;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  z-index: 1000;
  border-bottom: 1px solid var(--border-color);
}
.main-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: var(--spacing-xxxl);
}
.logo {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 1.5rem;
  color: var(--primary-color);
}
.nav-links {
  display: flex;
  align-items: center;
  gap: var(--spacing-xl);
  list-style: none;
}
.nav-link {
  font-family: var(--font-heading);
  font-weight: 700;
  color: var(--text-primary);
  padding: var(--spacing-s) 0;
  position: relative;
}
.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--accent-color);
  transition: width 0.3s ease;
}
.nav-link:hover::after, .nav-link.active::after {
  width: 100%;
}
.nav-link.active {
    color: var(--primary-color);
}

/* Dropdown */
.nav-dropdown { position: relative; }
.dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  background-color: white;
  min-width: 220px;
  list-style: none;
  padding: var(--spacing-m);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s;
  padding-left: 0;
}
.nav-dropdown:hover .dropdown-menu,
.nav-dropdown:focus-within .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.dropdown-menu li { padding: 0; }
.dropdown-menu li a {
  display: block;
  padding: var(--spacing-s) var(--spacing-m);
  color: var(--text-primary);
  font-family: var(--font-heading);
  border-radius: 4px;
}
.dropdown-menu li a:hover {
  background-color: var(--bg-light);
  color: var(--primary-color);
}

/* Hamburger */
.hamburger {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0;
    width: 24px;
    height: 18px;
    position: relative;
}
.hamburger span {
    display: block;
    width: 100%;
    height: 2px;
    background-color: var(--primary-color);
    position: absolute;
    left: 0;
    transition: all 0.3s ease;
}
.hamburger span:nth-child(1) { top: 0; }
.hamburger span:nth-child(2) { top: 8px; }
.hamburger span:nth-child(3) { bottom: 0; }

.hamburger.is-active span:nth-child(1) { transform: translateY(8px) rotate(45deg); }
.hamburger.is-active span:nth-child(2) { opacity: 0; }
.hamburger.is-active span:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }

/* --- HERO SECTIONS --- */
.hero {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-light);
  padding: 120px var(--spacing-l);
  background-size: cover;
  background-position: center;
}
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-color: rgba(0, 0, 0, 0.6);
}
.hero-content {
  position: relative;
  z-index: 1;
  max-width: 900px;
}
.hero-home {
  min-height: 80vh;
  background-image: url('https://images.pexels.com/photos/11122555/pexels-photo-11122555.jpeg?auto=compress&cs=tinysrgb&dpr=2&h=650&w=940');
}
.hero-page { min-height: 40vh; }
.hero-article {
    min-height: 40vh;
    background-color: var(--primary-color);
}
.hero-title { margin-bottom: var(--spacing-l); }
.hero-subtitle { font-size: 1.25rem; opacity: 0.9; }

/* --- SECTIONS & GRIDS --- */
.content-section {
  padding: var(--spacing-xxxl) 0;
}
.section-title {
  margin-bottom: var(--spacing-xxl);
}
.grid {
  display: grid;
  gap: var(--spacing-xl);
}
.grid-2-cols { grid-template-columns: 1fr; }
.grid-3-cols { grid-template-columns: 1fr; }
.grid-4-cols { grid-template-columns: 1fr; }

@media (min-width: 768px) {
  .grid-2-cols { grid-template-columns: repeat(2, 1fr); gap: var(--spacing-xxl); }
  .grid-3-cols { grid-template-columns: repeat(3, 1fr); }
  .grid-4-cols { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 1024px) {
  .grid-4-cols { grid-template-columns: repeat(4, 1fr); }
}

.align-center { align-items: center; }

/* --- COMPONENTS --- */
.btn {
  display: inline-block;
  font-family: var(--font-heading);
  font-weight: 700;
  padding: var(--spacing-m) var(--spacing-xl);
  border-radius: var(--border-radius);
  border: 2px solid transparent;
  cursor: pointer;
  transition: all 0.3s ease;
  font-size: 1rem;
}
.btn-primary {
  background-color: var(--accent-color);
  color: var(--text-primary);
  border-color: var(--accent-color);
}
.btn-primary:hover {
  background-color: transparent;
  color: var(--accent-color);
}
.btn-secondary {
    background-color: transparent;
    border-color: var(--text-secondary);
    color: var(--text-secondary);
}
.btn-secondary:hover {
    background-color: var(--text-secondary);
    color: white;
}
.btn-block {
    display: block;
    width: 100%;
    text-align: center;
}

.text-link {
  font-family: var(--font-heading);
  font-weight: 700;
  color: var(--accent-color);
}

.text-card {
    background: #fff;
    padding: var(--spacing-xl);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    height: 100%;
}

.feature-card {
    background: #fff;
    padding: var(--spacing-xl);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
}

.publications-list {
  display: grid;
  gap: var(--spacing-xl);
}
.publication-item {
  border-bottom: 1px solid var(--border-color);
  padding-bottom: var(--spacing-xl);
}
.publication-item:last-child { border-bottom: none; }
.publication-item h4 { margin-bottom: var(--spacing-s); }
.publication-item p { color: var(--text-secondary); margin-bottom: var(--spacing-m); }

/* --- ARTICLE STYLES --- */
.article-meta {
  font-family: var(--font-heading);
  font-weight: 700;
  color: var(--accent-color);
  margin-bottom: var(--spacing-m);
}
.article-title { margin: 0; }

.article-body {
  max-width: 800px;
  margin: 0 auto;
}
.article-body h2 {
    margin-top: var(--spacing-xxl);
    margin-bottom: var(--spacing-l);
    font-size: 1.8rem;
    border-bottom: 2px solid var(--accent-color);
    padding-bottom: var(--spacing-s);
}
.article-body figure {
    margin: var(--spacing-xl) 0;
}
.article-body figcaption {
    font-size: 0.9rem;
    color: var(--text-secondary);
    text-align: center;
    margin-top: var(--spacing-s);
}
.breadcrumbs {
  margin-bottom: var(--spacing-xl);
  font-size: 0.9rem;
}
.breadcrumbs ol {
  display: flex;
  flex-wrap: wrap;
  list-style: none;
  padding: 0;
  margin: 0;
}
.breadcrumbs li::after {
  content: '/';
  margin: 0 var(--spacing-s);
  color: var(--text-secondary);
}
.breadcrumbs li:last-child::after { content: ''; }
.breadcrumbs a { color: var(--text-secondary); }
.breadcrumbs span { color: var(--text-primary); font-weight: 700; }

.callout {
    background-color: var(--bg-light);
    border-left: 4px solid var(--accent-color);
    padding: var(--spacing-l);
    margin: var(--spacing-xl) 0;
    border-radius: 0 var(--border-radius) var(--border-radius) 0;
}

.diagram-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    background: var(--bg-light);
    border: 1px dashed var(--border-color);
    border-radius: var(--border-radius);
    padding: var(--spacing-xxl);
    margin: var(--spacing-xl) 0;
}
.diagram-box {
    text-align: center;
    font-family: var(--font-heading);
    color: var(--text-secondary);
}
.diagram-title { font-weight: 700; color: var(--primary-color); }
.diagram-content span {
    display: block;
    border: 1px solid var(--border-color);
    padding: var(--spacing-m);
    background: #fff;
    border-radius: var(--border-radius);
    margin-top: var(--spacing-m);
}
.diagram-arrows { font-size: 1.5rem; color: var(--accent-color); font-weight: 900; }


/* --- FOOTER --- */
.main-footer {
  background-color: var(--primary-color);
  color: var(--text-light);
  padding-top: var(--spacing-xxl);
}
.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-xl);
  padding-bottom: var(--spacing-xxl);
}
@media (min-width: 768px) {
  .footer-grid { grid-template-columns: 2fr 1fr 1fr 1fr; }
}
.footer-column h4 { color: var(--accent-color); font-size: 1.2rem; }
.footer-column p { color: #BDBDBD; }
.footer-column ul { list-style: none; padding: 0; }
.footer-column ul li { margin-bottom: var(--spacing-s); }
.footer-column a { color: #BDBDBD; }
.footer-column a:hover { color: var(--text-light); }

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: var(--spacing-l) 0;
  text-align: center;
  font-size: 0.9rem;
  color: #BDBDBD;
}

/* --- CONTACT PAGE --- */
.contact-form-wrapper {
    background-color: #fff;
    padding: var(--spacing-xl);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
}
.contact-form .form-group { margin-bottom: var(--spacing-l); }
.contact-form label { display: block; font-weight: 700; margin-bottom: var(--spacing-s); }
.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: var(--spacing-m);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-family: var(--font-body);
    font-size: 1rem;
}
.contact-form input:focus,
.contact-form textarea:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 2px rgba(79, 195, 247, 0.3);
}
.form-disclaimer {
    font-size: 0.8rem;
    color: var(--text-secondary);
    background: var(--bg-light);
    padding: var(--spacing-s);
    border-radius: 4px;
    margin-bottom: var(--spacing-l);
}
.contact-info .info-item {
    margin-bottom: var(--spacing-xl);
}
.contact-info h3 {
    font-size: 1.2rem;
    color: var(--primary-color);
}
.map-container {
  width: 100%;
  height: 450px;
  border-radius: var(--border-radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  margin: var(--spacing-xxl) 0;
}
.map-container iframe { width: 100%; height: 100%; border: none; }

/* --- THANK YOU PAGE --- */
.thank-you-section {
  min-height: 60vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: var(--spacing-xxxl) var(--spacing-l);
}
.thank-you-icon {
  width: 80px;
  height: 80px;
  background: var(--accent-color);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 30px;
}
.thank-you-icon svg { width: 40px; height: 40px; color: white; }
.thank-you-section h1 { font-size: clamp(2.5rem, 5vw, 4rem); }
.thank-you-section p { font-size: 1.2rem; color: var(--text-secondary); max-width: 600px; margin-bottom: var(--spacing-xl); }

/* --- COOKIE BANNER --- */
.cookie-banner {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background-color: var(--primary-color);
  color: var(--text-light);
  padding: var(--spacing-l);
  display: none;
  align-items: center;
  justify-content: space-between;
  gap: var(--spacing-l);
  z-index: 9999;
  box-shadow: 0 -4px 15px rgba(0,0,0,0.1);
}
.cookie-banner p { margin: 0; font-size: 0.9rem; }
.cookie-banner a { color: var(--accent-color); text-decoration: underline; }
.cookie-buttons { display: flex; gap: var(--spacing-m); }
.cookie-banner .btn { padding: var(--spacing-s) var(--spacing-m); }

/* --- RESPONSIVE --- */
@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: var(--spacing-xxxl);
    left: 0;
    width: 100%;
    height: calc(100vh - var(--spacing-xxxl));
    background-color: white;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xl);
    transform: translateX(-100%);
    transition: transform 0.3s ease;
    padding-left: 0;
  }
  .nav-links.is-active { transform: translateX(0); }
  .hamburger { display: block; }
  .nav-dropdown:hover .dropdown-menu {
      opacity: 0;
      visibility: hidden;
      transform: translateY(10px);
  }
  .nav-dropdown.open .dropdown-menu {
      position: static;
      opacity: 1;
      visibility: visible;
      transform: none;
      box-shadow: none;
      background: var(--bg-light);
      width: 100%;
      text-align: center;
  }
  .content-section { padding: var(--spacing-xxl) 0; }
  .grid-2-cols .content-image { order: -1; }
  .footer-grid { grid-template-columns: 1fr; }
  .cookie-banner { flex-direction: column; text-align: center; }
}