/* === Base Reset & Variables === */
:root {
  --color-bg: #ffffff;
  --color-text: #1a1a2e;
  --color-text-secondary: #4a4a6a;
  --color-accent: #c0392b;
  --color-accent-light: #e74c3c;
  --color-accent-dark: #a33025;
  --color-accent-bg: #fdf2f0;
  --color-border: #e0e0e8;
  --color-card-bg: #f8f8fc;
  --color-code-bg: #f4f4f8;
  --color-success: #27ae60;
  --color-warning: #f39c12;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
  --max-width: 960px;
  --section-gap: 4rem;
  --border-radius: 12px;
  --border-radius-sm: 8px;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.12);
  --transition: all 0.2s ease;
}

*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.7;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

/* === Layout === */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 2rem;
}

section {
  padding: var(--section-gap) 0;
}

section + section {
  border-top: 1px solid var(--color-border);
}

/* === Hero Section === */
.hero {
  text-align: center;
  padding: 5rem 0 3rem;
  background: linear-gradient(180deg, var(--color-accent-bg) 0%, var(--color-bg) 100%);
}

.hero h1 {
  font-size: 3rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 0.75rem;
  color: var(--color-accent);
  background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-accent-light) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero .subtitle {
  font-size: 1.2rem;
  color: var(--color-text-secondary);
  max-width: 720px;
  margin: 0 auto 2rem;
  line-height: 1.6;
  font-weight: 400;
}

/* === Author List === */
.authors {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.3rem 1.5rem;
  margin-bottom: 1.5rem;
  font-size: 1rem;
}

.authors .author {
  white-space: nowrap;
}

.authors .author a {
  color: var(--color-text);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: var(--transition);
}

.authors .author a:hover {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

.authors .corresponding {
  font-weight: 600;
}

.affiliations {
  font-size: 0.88rem;
  color: var(--color-text-secondary);
  margin-bottom: 2rem;
  line-height: 1.9;
}

.affiliations sup {
  color: var(--color-accent);
  font-weight: 600;
  margin-right: 2px;
}

/* === Buttons === */
.btn-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 1.4rem;
  border-radius: var(--border-radius-sm);
  font-size: 0.92rem;
  font-weight: 500;
  text-decoration: none;
  transition: var(--transition);
  border: 1.5px solid var(--color-border);
  color: var(--color-text);
  background: var(--color-bg);
}

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

.btn.primary {
  background: var(--color-accent);
  color: #fff;
  border-color: var(--color-accent);
}

.btn.primary:hover {
  background: var(--color-accent-light);
  border-color: var(--color-accent-light);
  color: #fff;
}

.btn.disabled {
  opacity: 0.6;
  cursor: not-allowed;
  pointer-events: none;
}

/* === Section Headers === */
.section-title {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  color: var(--color-text);
  letter-spacing: -0.02em;
}

.section-intro {
  margin-bottom: 2rem;
}

/* === Abstract === */
.abstract-text {
  font-size: 1.05rem;
  line-height: 1.85;
  color: var(--color-text-secondary);
  text-align: justify;
}

.abstract-text strong {
  color: var(--color-text);
}

.abstract-continued {
  margin-top: 1rem;
}

/* === Stats Section === */
.stats-section {
  padding: 2.5rem 0;
  background: var(--color-bg);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.2rem;
}

.stat-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  padding: 1.5rem 1rem;
  text-align: center;
  transition: var(--transition);
}

.stat-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-accent);
}

.stat-card .number {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--color-accent);
  font-family: var(--font-mono);
  line-height: 1.2;
}

.stat-card .label {
  font-size: 0.82rem;
  color: var(--color-text-secondary);
  margin-top: 0.4rem;
  font-weight: 500;
}

/* === Callout === */
.callout {
  background: linear-gradient(135deg, var(--color-accent-bg) 0%, #fff5f3 100%);
  border-left: 4px solid var(--color-accent);
  border-radius: 0 var(--border-radius) var(--border-radius) 0;
  padding: 1.5rem 2rem;
  margin-bottom: 2rem;
}

.callout p {
  font-size: 1.05rem;
  line-height: 1.7;
  color: var(--color-text-secondary);
  margin: 0;
}

.callout strong {
  color: var(--color-accent-dark);
}

/* === Impact Grid === */
.impact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.impact-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  padding: 1.75rem;
  text-align: center;
  transition: var(--transition);
}

.impact-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.impact-icon {
  width: 56px;
  height: 56px;
  margin: 0 auto 1rem;
  background: var(--color-accent-bg);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  color: var(--color-accent);
}

.impact-card h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--color-text);
}

.impact-card p {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

/* === Figures === */
.figure-block {
  margin: 2rem 0;
}

.figure-block img {
  width: 100%;
  border-radius: var(--border-radius-sm);
  border: 1px solid var(--color-border);
  transition: var(--transition);
}

.figure-block img:hover {
  box-shadow: var(--shadow-md);
}

.figure-block.half img {
  width: 85%;
  display: block;
  margin: 0 auto;
}

.figure-caption {
  font-size: 0.88rem;
  color: var(--color-text-secondary);
  margin-top: 0.75rem;
  text-align: center;
  line-height: 1.6;
}

/* === Properties Cards === */
.properties-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.2rem;
  margin-bottom: 2rem;
}

.property-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  padding: 1.5rem;
  text-align: center;
  transition: var(--transition);
}

.property-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-accent);
}

.property-icon {
  width: 48px;
  height: 48px;
  margin: 0 auto 1rem;
  background: var(--color-accent-bg);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  color: var(--color-accent);
}

.property-card h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--color-accent);
}

.property-card p {
  font-size: 0.88rem;
  color: var(--color-text-secondary);
  line-height: 1.55;
}

/* === Properties Table === */
.properties-table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.9rem;
  border-radius: var(--border-radius);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.properties-table th,
.properties-table td {
  padding: 0.85rem 1rem;
  text-align: center;
  border-bottom: 1px solid var(--color-border);
}

.properties-table th {
  background: var(--color-card-bg);
  font-weight: 600;
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-text-secondary);
}

.properties-table td:first-child {
  text-align: left;
  font-weight: 500;
}

.properties-table tbody tr {
  transition: var(--transition);
}

.properties-table tbody tr:hover {
  background: var(--color-accent-bg);
}

.properties-table .highlight-row {
  background: var(--color-accent-bg);
}

.properties-table .highlight-row:hover {
  background: #fde8e5;
}

.properties-table .check {
  color: var(--color-success);
}

.properties-table .cross {
  color: var(--color-accent);
}

/* === Defense Table Specific === */
.defense-table .detected {
  color: var(--color-accent);
  font-weight: 600;
}

.defense-table .bypassed {
  color: var(--color-success);
  font-weight: 600;
}

.defense-table .low {
  color: var(--color-warning);
}

.defense-table .na {
  color: var(--color-text-secondary);
  opacity: 0.6;
}

.table-note {
  font-size: 0.82rem;
  color: var(--color-text-secondary);
  text-align: center;
  margin-top: 0.75rem;
  font-style: italic;
}

/* === Method Steps === */
.method-steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.2rem;
  margin: 1.5rem 0;
}

.method-step {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  padding: 1.5rem;
  position: relative;
  transition: var(--transition);
}

.method-step:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-accent);
}

.step-number {
  position: absolute;
  top: -10px;
  left: 1.5rem;
  width: 28px;
  height: 28px;
  background: var(--color-accent);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.85rem;
  font-weight: 600;
  box-shadow: var(--shadow-sm);
}

.method-step h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  margin-top: 0.25rem;
  color: var(--color-accent);
}

.method-step p {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

.method-step code {
  background: var(--color-code-bg);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  font-size: 0.8rem;
  font-family: var(--font-mono);
  color: var(--color-text);
}

/* === Result Highlights === */
.result-highlight {
  background: linear-gradient(135deg, var(--color-accent-bg) 0%, #fff5f3 100%);
  border-radius: var(--border-radius);
  padding: 1.25rem 1.5rem;
  margin: 2rem 0 1rem;
  border-left: 4px solid var(--color-accent);
}

.result-highlight h3 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 0.35rem;
}

.result-highlight p {
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  margin: 0;
  line-height: 1.6;
}

.result-highlight strong {
  color: var(--color-accent);
}

/* === Results Grid === */
.results-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
  margin: 1.5rem 0;
}

.results-grid .figure-block {
  margin: 0;
}

/* === Defense Grid === */
.defense-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.2rem;
  margin-top: 1.5rem;
}

.defense-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  padding: 1.5rem;
  transition: var(--transition);
}

.defense-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-success);
}

.defense-icon {
  width: 44px;
  height: 44px;
  background: rgba(39, 174, 96, 0.1);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  color: var(--color-success);
  margin-bottom: 1rem;
}

.defense-card h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--color-text);
}

.defense-card p {
  font-size: 0.88rem;
  color: var(--color-text-secondary);
  line-height: 1.55;
}

/* === BibTeX === */
.bibtex-block {
  background: var(--color-code-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-sm);
  padding: 1.5rem;
  position: relative;
  overflow-x: auto;
}

.bibtex-block code {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.7;
  display: block;
  white-space: pre;
  color: var(--color-text);
}

.copy-btn {
  position: absolute;
  top: 0.75rem;
  right: 0.75rem;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: 0.4rem 0.75rem;
  font-size: 0.78rem;
  font-weight: 500;
  cursor: pointer;
  color: var(--color-text-secondary);
  transition: var(--transition);
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.copy-btn:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  background: var(--color-accent-bg);
}

.copy-btn.copied {
  border-color: var(--color-success);
  color: var(--color-success);
  background: rgba(39, 174, 96, 0.1);
}

/* === Footer === */
footer {
  text-align: center;
  padding: 2.5rem 0;
  border-top: 1px solid var(--color-border);
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  background: var(--color-card-bg);
}

/* === Responsive === */
@media (max-width: 900px) {
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .properties-cards {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 768px) {
  :root {
    --section-gap: 3rem;
  }

  .hero h1 {
    font-size: 2.2rem;
  }

  .hero .subtitle {
    font-size: 1rem;
  }

  .section-title {
    font-size: 1.5rem;
  }

  .method-steps,
  .results-grid,
  .defense-grid {
    grid-template-columns: 1fr;
  }

  .container {
    padding: 0 1.25rem;
  }

  .callout {
    padding: 1.25rem 1.5rem;
  }

  .abstract-text {
    text-align: left;
  }

  .properties-table {
    font-size: 0.82rem;
  }

  .properties-table th,
  .properties-table td {
    padding: 0.65rem 0.5rem;
  }
}

@media (max-width: 480px) {
  .stats-grid {
    grid-template-columns: 1fr;
  }

  .hero h1 {
    font-size: 1.8rem;
  }

  .stat-card .number {
    font-size: 1.5rem;
  }

  .btn-row {
    flex-direction: column;
    align-items: stretch;
  }

  .btn {
    justify-content: center;
  }

  .figure-block.half img {
    width: 100%;
  }
}

/* === Print Styles === */
@media print {
  .hero {
    background: none;
    padding: 2rem 0;
  }

  .btn-row {
    display: none;
  }

  section {
    padding: 2rem 0;
    page-break-inside: avoid;
  }

  .stat-card,
  .method-step,
  .impact-card,
  .property-card,
  .defense-card {
    box-shadow: none;
    border: 1px solid #ddd;
  }

  .copy-btn {
    display: none;
  }

  a {
    color: var(--color-text);
    text-decoration: none;
  }

  .figure-block img {
    max-width: 100%;
    page-break-inside: avoid;
  }
}