:root {
  /* Clean White Theme - LIFT Style */
  --bg-gradient: #ffffff;
  --accent: #5b8def;
  --accent-dark: #4a7cd6;
  --accent-light: #7ba3f3;
  --accent-glow: rgba(91, 141, 239, 0.3);
  --text-primary: #000000;
  --text-secondary: #333333;
  --text-muted: #666666;
  --text-light: #999999;
  --surface: #ffffff;
  --surface-alt: #fafafa;
  --surface-hover: #f5f5f5;
  --border: rgba(0, 0, 0, 0.1);
  --border-light: rgba(0, 0, 0, 0.06);
  --shadow: 0 2px 15px rgba(0, 0, 0, 0.08);
  --shadow-sm: 0 1px 8px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.12);
  font-size: 16px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  margin: 0;
  background: #ffffff;
  color: var(--text-secondary);
  line-height: 1.65;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.25s ease;
}

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

ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

img {
  max-width: 100%;
  display: block;
  border-radius: 8px;
}

h2, h3, h4 {
  font-family: 'Inter', sans-serif;
  color: var(--text-primary);
  font-weight: 600;
}

p {
  margin: 0.8rem 0;
}

/* Hero Section - Centered Layout (LIFT Style) */
.hero {
  min-height: 70vh;
  padding: 4rem clamp(2rem, 4vw, 5rem) 2rem;
  background: #ffffff;
  position: relative;
  overflow: visible;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  text-align: center;
}

/* Navigation */
.nav {
  position: absolute;
  top: 2rem;
  left: clamp(2rem, 4vw, 5rem);
  right: clamp(2rem, 4vw, 5rem);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1.5rem;
  z-index: 10;
}

.brand {
  font-family: 'Space Grotesk', sans-serif;
  font-weight: 600;
  font-size: 1.3rem;
  color: var(--text-primary);
  letter-spacing: 0.08em;
}

.nav-links {
  display: flex;
  gap: 1.2rem;
  font-size: 0.95rem;
}

.nav-links a {
  color: var(--text-secondary);
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  transition: background 0.3s ease, color 0.3s ease;
  font-weight: 500;
}

.nav-links a:hover {
  background: rgba(99, 102, 241, 0.1);
  color: var(--accent);
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border: 1px solid rgba(0, 0, 0, 0.15);
  border-radius: 12px;
  background: var(--surface);
  position: relative;
  cursor: pointer;
}

.nav-toggle::before,
.nav-toggle::after {
  content: "";
  position: absolute;
  left: 12px;
  right: 12px;
  height: 2px;
  background: var(--text-primary);
  transition: transform 0.3s ease, top 0.3s ease;
}

.nav-toggle::before {
  top: 16px;
}

.nav-toggle::after {
  top: 24px;
}

.nav-toggle.open::before {
  transform: rotate(45deg);
  top: 20px;
}

.nav-toggle.open::after {
  transform: rotate(-45deg);
  top: 20px;
}

/* Hero Content - Centered */
.hero-content {
  position: relative;
  z-index: 2;
  max-width: 900px;
  margin: 0 auto;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.4rem 1rem;
  border-radius: 999px;
  background: rgba(91, 141, 239, 0.1);
  color: var(--accent);
  font-weight: 600;
  font-size: 0.875rem;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  border: none;
  margin-bottom: 2rem;
}

h1 {
  font-family: 'Inter', sans-serif;
  font-size: clamp(2.5rem, 5vw, 3.5rem);
  margin: 0 0 1.2rem;
  color: var(--text-primary);
  letter-spacing: -0.03em;
  font-weight: 700;
  line-height: 1.2;
}

.hero-subtitle {
  font-size: clamp(1.1rem, 2.5vw, 1.35rem);
  color: var(--text-secondary);
  margin: 0 0 1.2rem;
  font-weight: 400;
  line-height: 1.5;
}

.hero-copy {
  max-width: 700px;
  margin: 0 auto 2rem;
  font-size: 1.05rem;
  color: var(--text-muted);
  line-height: 1.8;
}

.cta-group {
  display: flex;
  gap: 1rem;
  margin-bottom: 2.5rem;
  flex-wrap: wrap;
  justify-content: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.8rem 1.6rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-weight: 600;
  letter-spacing: 0.01em;
  transition: transform 0.25s ease, box-shadow 0.25s ease, background 0.25s ease;
  cursor: pointer;
  font-size: 0.95rem;
}

.btn.primary {
  background: var(--accent);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(99, 102, 241, 0.4);
}

.btn.primary:hover {
  transform: translateY(-2px);
  background: var(--accent-dark);
  box-shadow: 0 6px 20px rgba(99, 102, 241, 0.5);
}

.btn.outline {
  border: 1.5px solid var(--border);
  color: var(--text-primary);
  background: var(--surface);
}

.btn.outline:hover {
  background: var(--surface-hover);
  transform: translateY(-2px);
  border-color: var(--accent);
  box-shadow: var(--shadow-sm);
}

.btn.small {
  padding: 0.6rem 1.2rem;
  font-size: 0.9rem;
}

.author-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.2rem;
  color: var(--text-muted);
  font-size: 0.95rem;
  margin: 0 auto 0.8rem;
  justify-content: center;
}

.affiliation-note {
  font-size: 0.85rem;
  color: var(--text-light);
  font-style: italic;
  margin: 0.5rem 0;
}

.institution-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.2rem;
  font-size: 0.88rem;
  color: var(--text-light);
  margin-top: 1rem;
  justify-content: center;
}

.institution-list span::before {
  content: "•";
  margin-right: 0.4rem;
  color: var(--accent);
}

/* Hero Teaser Section - Side by Side Layout */
.hero-teaser-section {
  position: relative;
  z-index: 2;
  max-width: 1200px;
  margin: 3rem auto 0;
  padding: 0 2rem;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

.teaser-text {
  padding-right: 1rem;
}

.teaser-text h2 {
  font-size: 1.8rem;
  margin: 0 0 1rem;
  color: var(--text-primary);
  font-weight: 600;
  letter-spacing: -0.02em;
}

.teaser-text p {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-secondary);
  margin: 0.8rem 0;
}

.teaser-figure {
  background: #ffffff;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 2px 16px rgba(0, 0, 0, 0.08);
  border: 1px solid var(--border-light);
}

.teaser-figure img {
  width: 100%;
  display: block;
  border-radius: 0;
}

.teaser-figure figcaption {
  padding: 1rem 1.2rem;
  text-align: center;
  font-size: 0.85rem;
  line-height: 1.5;
  color: var(--text-muted);
  background: #fafafa;
}

/* Section Styles */
.section {
  padding: clamp(3.5rem, 7vw, 6rem) clamp(2rem, 5vw, 5rem);
  background: var(--surface);
}

.section:nth-of-type(even) {
  background: var(--surface-alt);
}

.section.accent {
  background: #fafafa;
}

.section-heading {
  margin-bottom: 2.5rem;
  text-align: center;
}

.section-heading h2 {
  margin: 0 0 0.8rem;
  font-family: 'Inter', sans-serif;
  font-size: clamp(2rem, 4vw, 2.8rem);
  color: var(--text-primary);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.section-heading p {
  margin: 0 auto;
  max-width: 650px;
  color: var(--text-muted);
  font-size: 1.05rem;
}

.section-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: clamp(1.5rem, 5vw, 3.5rem);
  margin-top: 2.5rem;
  align-items: start;
}

.section-grid-compact {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
  margin-top: 2rem;
  align-items: start;
}

.text-col {
  font-size: 1.02rem;
  line-height: 1.8;
}

.text-col p {
  margin: 1rem 0;
  color: var(--text-secondary);
}

.text-col strong {
  color: var(--accent);
  font-weight: 600;
}

.text-col em {
  color: var(--text-primary);
}

.media-col {
  background: var(--surface);
  padding: 1.2rem;
  border-radius: 16px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.media-col.wide {
  grid-column: 1 / -1;
}

.media-col img {
  border-radius: 12px;
  width: 100%;
  border: 1px solid var(--border-light);
}

.media-col figcaption {
  font-size: 0.9rem;
  margin-top: 0.8rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* Card Layouts */
.card-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
  margin-top: 2.5rem;
}

.card {
  padding: 1.8rem;
  background: var(--surface);
  border-radius: 16px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-light);
  box-shadow: var(--shadow);
}

.card h3 {
  margin-top: 0;
  margin-bottom: 0.8rem;
  color: var(--text-primary);
  font-family: 'Inter', sans-serif;
  font-size: 1.1rem;
  font-weight: 600;
}

.card p {
  margin-bottom: 0;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* Method Blocks */
.method-blocks {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  margin-top: 2.5rem;
}

.method-block {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1.5rem;
  padding: 2rem;
  background: var(--surface);
  border-radius: 16px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  align-items: start;
}

.method-number {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: var(--accent);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  font-weight: 600;
  font-family: 'Inter', sans-serif;
  flex-shrink: 0;
}

.method-content h3 {
  margin: 0 0 0.8rem;
  color: var(--text-primary);
  font-size: 1.3rem;
}

.method-content p {
  margin: 0;
  color: var(--text-secondary);
  line-height: 1.8;
}

.method-content em {
  color: var(--text-primary);
  font-style: normal;
  font-family: 'Courier New', monospace;
  font-size: 0.95rem;
  background: rgba(99, 102, 241, 0.08);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
}

/* Pills */
.pill {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 1.5rem;
  margin-bottom: 1.2rem;
  box-shadow: var(--shadow-sm);
}

.pill h3 {
  margin: 0 0 0.6rem;
  color: var(--text-primary);
  font-family: 'Space Grotesk', sans-serif;
  font-size: 1.1rem;
}

.pill p {
  margin: 0;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* Masonry / Tiles */
.masonry {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 2.5rem;
}

.tile {
  background: var(--surface);
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.tile:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}

.tile img {
  border-bottom: 1px solid var(--border);
  border-radius: 0;
}

.tile-body {
  padding: 1.5rem;
}

.tile-body h3 {
  margin: 0 0 0.6rem;
  color: var(--text-primary);
  font-family: 'Space Grotesk', sans-serif;
}

.tile-body p {
  margin: 0;
  color: var(--text-secondary);
}

/* Highlight Box */
.highlight {
  margin-top: 3rem;
  padding: 2rem;
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.05), rgba(168, 85, 247, 0.03));
  border-radius: 20px;
  border: 1px solid rgba(99, 102, 241, 0.2);
  display: grid;
  gap: 2rem;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  align-items: center;
}

.highlight-copy h3 {
  margin: 0 0 0.8rem;
  color: var(--text-primary);
  font-family: 'Space Grotesk', sans-serif;
  font-size: 1.4rem;
}

.highlight-copy p {
  margin: 0;
  line-height: 1.8;
  color: var(--text-secondary);
}

.highlight img {
  border-radius: 12px;
  border: 1px solid var(--border);
}

.centered {
  margin: 2.5rem auto 0;
  max-width: 960px;
  text-align: center;
}

.centered figcaption {
  margin-top: 0.8rem;
  color: var(--text-muted);
}

/* Results Subsections */
.results-subsection {
  margin-top: 3.5rem;
  padding-top: 2.5rem;
  border-top: 2px solid var(--border-light);
}

.results-subsection:first-child {
  margin-top: 0;
  padding-top: 0;
  border-top: none;
}

.subsection-title {
  font-size: 1.8rem;
  margin: 0 0 1.5rem;
  color: var(--text-primary);
  font-weight: 600;
  text-align: center;
}

/* Tables */
.table-container {
  margin: 2rem 0;
  overflow-x: auto;
}

.table-caption {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-bottom: 1rem;
  line-height: 1.6;
  text-align: center;
}

.results-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--surface);
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--border);
  font-size: 0.9rem;
}

.results-table thead {
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.08), rgba(168, 85, 247, 0.05));
}

.results-table th {
  padding: 1rem 0.8rem;
  text-align: left;
  color: var(--text-primary);
  font-weight: 600;
  border-bottom: 2px solid var(--border);
  font-family: 'Space Grotesk', sans-serif;
}

.results-table td {
  padding: 0.8rem;
  border-bottom: 1px solid var(--border-light);
  color: var(--text-secondary);
}

.results-table tbody tr:hover {
  background: var(--surface-hover);
}

.results-table tbody tr:last-child td {
  border-bottom: none;
}

.results-table .best-row {
  background: rgba(99, 102, 241, 0.05);
  font-weight: 500;
}

.results-table .best-row td {
  color: var(--text-primary);
}

.results-table.compact td,
.results-table.compact th {
  padding: 0.6rem 0.7rem;
  font-size: 0.88rem;
}

.highlight-best {
  color: var(--accent);
  font-weight: 700;
}

.highlight-second {
  color: var(--accent-light);
  font-weight: 600;
}

/* Resources */
.resource-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
  margin-top: 2.5rem;
}

.resource-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 1.8rem;
  box-shadow: var(--shadow-sm);
  transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

.resource-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-light);
  box-shadow: var(--shadow);
}

.resource-card h3 {
  margin-top: 0;
  margin-bottom: 0.8rem;
  color: var(--text-primary);
  font-family: 'Space Grotesk', sans-serif;
}

.resource-card p {
  margin-bottom: 1rem;
  color: var(--text-secondary);
}

.resource-card a {
  color: var(--accent);
  transition: color 0.25s ease;
}

.resource-card a:hover {
  color: var(--accent-dark);
  text-decoration: underline;
}

/* BibTeX */
.bibtex {
  margin-top: 2.5rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 1.8rem;
  overflow-x: auto;
  box-shadow: var(--shadow-sm);
}

.bibtex h3 {
  margin-top: 0;
  margin-bottom: 1rem;
  color: var(--text-primary);
  font-family: 'Space Grotesk', sans-serif;
}

.bibtex pre {
  white-space: pre-wrap;
  margin: 0;
  font-family: 'Courier New', monospace;
  font-size: 0.88rem;
  line-height: 1.6;
  color: var(--text-secondary);
  background: var(--surface-alt);
  padding: 1rem;
  border-radius: 8px;
}

.bibtex code {
  font-family: inherit;
}

/* Acknowledgements */
.acknowledgements {
  margin-top: 2.5rem;
  padding: 1.8rem;
  background: var(--surface-alt);
  border-radius: 16px;
  border: 1px solid var(--border-light);
}

.acknowledgements h3 {
  margin-top: 0;
  margin-bottom: 1rem;
  color: var(--text-primary);
  font-family: 'Space Grotesk', sans-serif;
}

.acknowledgements p {
  color: var(--text-secondary);
  line-height: 1.7;
  font-size: 0.95rem;
}

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

/* Footer */
.footer {
  text-align: center;
  padding: 2.5rem 2rem;
  background: var(--surface-alt);
  color: var(--text-muted);
  font-size: 0.9rem;
  border-top: 1px solid var(--border-light);
}

.footer p {
  margin: 0.3rem 0;
}

.back-to-top {
  display: inline-block;
  margin-top: 0.8rem;
  color: var(--accent);
  font-weight: 600;
  transition: transform 0.25s ease;
}

.back-to-top:hover {
  transform: translateY(-2px);
}

/* Responsive Design */
@media (max-width: 900px) {
  .nav {
    position: static;
    margin-bottom: 2rem;
  }

  .nav-toggle {
    display: inline-block;
  }

  .nav-links {
    position: absolute;
    right: 2rem;
    top: 5.5rem;
    flex-direction: column;
    gap: 0.8rem;
    background: var(--surface);
    padding: 1rem 1.2rem;
    border-radius: 12px;
    border: 1px solid var(--border);
    box-shadow: var(--shadow-lg);
    display: none;
  }

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

  .hero {
    padding-top: 2rem;
    min-height: 85vh;
  }

  .hero-teaser-section {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .section {
    padding: clamp(2.5rem, 5vw, 4rem) clamp(1.5rem, 4vw, 3rem);
  }

  .section-heading h2 {
    font-size: clamp(2rem, 5vw, 2.8rem);
  }

  h1 {
    font-size: clamp(2.5rem, 8vw, 3.8rem);
  }

  .highlight {
    grid-template-columns: 1fr;
  }

  .masonry {
    grid-template-columns: 1fr;
  }

  .card-row {
    grid-template-columns: 1fr;
  }

  .method-blocks {
    gap: 1.2rem;
  }

  .method-block {
    grid-template-columns: 1fr;
    gap: 1rem;
    padding: 1.5rem;
  }

  .method-number {
    width: 45px;
    height: 45px;
    font-size: 1.3rem;
  }

  .section-grid {
    grid-template-columns: 1fr;
  }

  .section-grid-compact {
    grid-template-columns: 1fr;
  }

  .results-table {
    font-size: 0.8rem;
  }

  .results-table th,
  .results-table td {
    padding: 0.6rem 0.5rem;
  }
}

@media (max-width: 600px) {
  .cta-group {
    flex-direction: column;
    width: 100%;
  }

  .btn {
    width: 100%;
    justify-content: center;
  }

  .institution-list {
    flex-direction: column;
    gap: 0.3rem;
  }

  .author-list {
    flex-direction: column;
    gap: 0.4rem;
  }
}

/* Animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.section {
  animation: fadeInUp 0.6s ease-out;
}

/* Scrollbar Styling */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

::-webkit-scrollbar-track {
  background: var(--surface-alt);
}

::-webkit-scrollbar-thumb {
  background: rgba(99, 102, 241, 0.3);
  border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
  background: rgba(99, 102, 241, 0.5);
}