/* ========================================
   GLOBAL STYLES
   ======================================== */

:root {
  --bg-primary: #1f2937;
  --bg-secondary: #2d3748;
  --accent-primary: #e6c547;
  --accent-secondary: #58a6ff;
  --text-primary: #f0f6fc;
  --text-muted: #a0aec0;
  --border-color: #4a5568;
  --heatmap-low: #0066ff;
  --heatmap-high: #ffd700;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ========================================
   TYPOGRAPHY
   ======================================== */

h1 {
  font-size: 3.5rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  letter-spacing: -0.02em;
}

h2 {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  letter-spacing: -0.01em;
}

h3 {
  font-size: 1.3rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

p {
  margin-bottom: 1rem;
  color: var(--text-primary);
}

a {
  color: var(--accent-secondary);
  text-decoration: none;
  transition: color 0.3s ease;
}

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

code {
  background-color: var(--bg-secondary);
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
  font-family: 'Courier New', monospace;
  font-size: 0.9rem;
}

/* ========================================
   BUTTONS
   ======================================== */

.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  border-radius: 6px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  border: none;
  text-align: center;
  font-size: 1rem;
}

.btn-primary {
  background-color: var(--accent-primary);
  color: #000;
}

.btn-primary:hover {
  background-color: #f5d76e;
  transform: translateY(-2px);
}

.btn-secondary {
  background-color: transparent;
  color: var(--accent-secondary);
  border: 2px solid var(--accent-secondary);
}

.btn-secondary:hover {
  background-color: var(--accent-secondary);
  color: var(--bg-primary);
  transform: translateY(-2px);
}

.btn-large {
  padding: 1rem 2rem;
  font-size: 1.1rem;
}

.copy-btn {
  background-color: var(--accent-secondary);
  color: var(--bg-primary);
  border: none;
  padding: 0.4rem 0.8rem;
  border-radius: 4px;
  cursor: pointer;
  font-weight: 600;
  font-size: 0.85rem;
  margin-left: 0.5rem;
  transition: background-color 0.3s ease;
}

.copy-btn:hover {
  background-color: var(--accent-primary);
  color: #000;
}

/* ========================================
   SECTIONS
   ======================================== */

section {
  padding: 4rem 0;
  border-bottom: 1px solid var(--border-color);
}

section:last-of-type {
  border-bottom: none;
}

/* Hero */
.hero {
  background: linear-gradient(135deg, rgba(31, 41, 55, 0.85) 0%, rgba(45, 55, 72, 0.85) 100%),
              url('hero-image.webp') center/cover no-repeat;
  padding: 6rem 0;
  text-align: center;
  min-height: 500px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero h1 {
  color: var(--accent-primary);
  margin-bottom: 1rem;
}

.subtitle {
  font-size: 1.3rem;
  color: var(--text-muted);
  margin-bottom: 2rem;
}

.cta-buttons {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 2rem;
}

/* About */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: start;
}

.about-facts h2 {
  color: var(--accent-primary);
  margin-bottom: 1.5rem;
}

.facts-list {
  list-style: none;
}

.facts-list li {
  padding: 0.75rem 0;
  border-bottom: 1px solid var(--border-color);
  font-size: 1.05rem;
}

.facts-list li:last-child {
  border-bottom: none;
}

.facts-list strong {
  color: var(--accent-secondary);
}

.trust-measures-definitions {
  margin-top: 2rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
}

.trust-measures-definitions h3 {
  color: var(--accent-secondary);
  font-size: 1.1rem;
  margin-bottom: 1rem;
}

.trust-measures-definitions p {
  margin-bottom: 0.75rem;
  font-size: 0.95rem;
  line-height: 1.5;
  color: var(--text-primary);
}

.trust-measures-definitions strong {
  color: var(--accent-secondary);
}

.about-text h2 {
  color: var(--accent-primary);
}

.citation-box {
  background-color: var(--bg-secondary);
  padding: 1.5rem;
  border-left: 4px solid var(--accent-primary);
  border-radius: 4px;
  margin-top: 2rem;
}

.citation-label {
  font-weight: 600;
  color: var(--accent-secondary);
  margin-bottom: 0.5rem;
}

.citation-content {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 0.75rem;
}

.citation-content code {
  flex: 1;
  min-width: 250px;
  background-color: var(--bg-primary);
  padding: 0.75rem;
}

.citation-note {
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* Heatmap */
.heatmap-section {
  background-color: var(--bg-secondary);
}

.heatmap-section h2 {
  color: var(--accent-primary);
}

.section-description {
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  font-size: 1rem;
}

.controls {
  margin-bottom: 2rem;
  display: flex;
  gap: 1rem;
  align-items: center;
  flex-wrap: wrap;
}

.controls label {
  font-weight: 600;
  color: var(--accent-secondary);
}

.controls select {
  padding: 0.5rem 1rem;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  cursor: pointer;
  font-family: 'Inter', sans-serif;
}

.controls select:hover {
  border-color: var(--accent-primary);
}

#heatmap-container {
  background-color: var(--bg-primary);
  padding: 2rem;
  border-radius: 8px;
  overflow-x: auto;
  margin-bottom: 1rem;
  display: flex;
  justify-content: center;
}

.heatmap-note {
  font-size: 0.9rem;
  color: var(--text-muted);
  text-align: center;
}

/* Explorer */
.explorer-section h2 {
  color: var(--accent-primary);
}

.explorer-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  margin-top: 2rem;
}

.explorer-map-panel {
  background-color: var(--bg-secondary);
  padding: 1.5rem;
  border-radius: 8px;
}

.explorer-map-panel h3 {
  color: var(--accent-secondary);
  margin-bottom: 1rem;
}

#outgoing-map svg,
#incoming-map svg {
  width: 100%;
  height: auto;
  display: block;
}

/* Map country styling */
.map-country {
  stroke: var(--bg-primary);
  stroke-width: 0.5px;
  cursor: pointer;
  transition: opacity 0.15s ease;
}

.map-country:hover {
  opacity: 0.8;
  stroke: var(--accent-secondary);
  stroke-width: 1.5px;
}

.map-country-nodata {
  fill: #3a3f4b;
}

/* Download */
.download-section {
  text-align: center;
  background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
}

.download-section h2 {
  color: var(--accent-primary);
  margin-bottom: 1rem;
}

.download-section p {
  margin-bottom: 1.5rem;
}

.download-buttons {
  display: flex;
  gap: 1.5rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 1.5rem;
}

.download-note {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-top: 1.5rem;
}

/* Footer */
.footer {
  background-color: var(--bg-secondary);
  padding: 2rem 0;
  text-align: center;
  border-top: 1px solid var(--border-color);
}

.footer p {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}

.footer strong {
  color: var(--accent-secondary);
}

/* ========================================
   RESPONSIVE DESIGN
   ======================================== */

@media (max-width: 768px) {
  h1 {
    font-size: 2.5rem;
  }

  h2 {
    font-size: 1.8rem;
  }

  section {
    padding: 2.5rem 0;
  }

  .about-grid,
  .explorer-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .cta-buttons {
    flex-direction: column;
    align-items: center;
  }

  .btn {
    width: 100%;
    max-width: 300px;
  }

  .citation-content {
    flex-direction: column;
  }

  .citation-content code {
    width: 100%;
    min-width: auto;
  }

  .copy-btn {
    width: 100%;
  }

  .controls {
    flex-direction: column;
    align-items: flex-start;
  }

  .controls select {
    width: 100%;
  }

  #heatmap-container {
    padding: 1rem;
    font-size: 0.9rem;
  }
}

/* ========================================
   D3 HEATMAP STYLING
   ======================================== */

.cell {
  stroke: var(--bg-primary);
  stroke-width: 1px;
  cursor: pointer;
}

.cell:hover {
  stroke: var(--accent-secondary);
  stroke-width: 2px;
}

.tooltip {
  position: absolute;
  background-color: var(--bg-secondary);
  color: var(--text-primary);
  padding: 0.75rem;
  border: 1px solid var(--accent-primary);
  border-radius: 4px;
  font-size: 0.9rem;
  pointer-events: none;
  z-index: 1000;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.5);
}

.axis-label {
  font-size: 12px;
  fill: var(--text-muted);
}

.axis-label:hover {
  fill: var(--accent-secondary);
  font-weight: 600;
}