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

:root {
  --accent: #10B981;
  --accent-hover: #059669;
  --bg: #ffffff;
  --bg-alt: #f8faf9;
  --text: #1a1a1a;
  --text-muted: #666666;
  --border: #e0e0e0;
  --font: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'SF Mono', Consolas, monospace;
}

html {
  background: var(--bg);
}

body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1rem 0;
}

/* Header Bar */
header {
  position: sticky;
  top: 0;
  background: var(--bg);
  z-index: 100;
  margin: 0 -1rem;
  padding: 0 1rem;
}

header::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 100vw;
  height: 1px;
  background: var(--border);
}

.header-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.75rem 0;
  max-width: 1200px;
  margin: 0 auto;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
  font-size: 1.1rem;
  text-decoration: none;
  color: var(--text);
}

.logo:hover {
  opacity: 0.8;
}

.logo-icon {
  flex-shrink: 0;
}

.header-right {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.view-count {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.logo-text {
  color: var(--accent);
}

/* Share Button */
.share-btn {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.5rem 0.9rem;
  background: var(--accent);
  color: white;
  border: none;
  border-radius: 6px;
  font-size: 0.85rem;
  font-weight: 500;
  font-family: var(--font);
  cursor: pointer;
  transition: background 0.15s;
}

.share-btn:hover {
  background: var(--accent-hover);
}

/* Intro */
.intro {
  padding: 2rem 0 1.5rem;
}

h1 {
  font-size: 1.75rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.nominal-tag {
  font-weight: 400;
  color: var(--text-muted);
}

.description {
  color: var(--text-muted);
  font-size: 0.95rem;
  max-width: 700px;
}

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

.description a:hover {
  text-decoration: underline;
}

/* Chart Section */
.chart-section {
  margin-bottom: 3rem;
}

.chart-layout {
  display: flex;
  gap: 1rem;
  min-height: 450px;
}

/* Country Panel */
.country-panel {
  width: 240px;
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  background: var(--bg);
}

.panel-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.6rem 0.75rem;
  border-bottom: 1px solid var(--border);
  background: var(--bg-alt);
}

.panel-title {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-muted);
}

.clear-btn {
  padding: 0.25rem 0.5rem;
  background: none;
  border: 1px solid var(--border);
  border-radius: 4px;
  font-size: 0.75rem;
  color: var(--text-muted);
  cursor: pointer;
  font-family: var(--font);
}

.clear-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.country-search {
  padding: 0.5rem;
  border-bottom: 1px solid var(--border);
}

.country-search input {
  width: 100%;
  padding: 0.5rem 0.6rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  font-size: 0.85rem;
  font-family: var(--font);
}

.country-search input:focus {
  outline: none;
  border-color: var(--accent);
}

.country-list {
  flex: 1;
  overflow-y: auto;
  max-height: 380px;
}

.country-section-label {
  padding: 0.4rem 0.6rem;
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  background: var(--bg-alt);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 1;
}

.country-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.45rem 0.6rem;
  cursor: pointer;
  font-size: 0.85rem;
  border-bottom: 1px solid var(--border);
  transition: background 0.1s;
}

.country-item:hover {
  background: var(--bg-alt);
}

.country-item.selected {
  background: var(--bg-alt);
}

.country-checkbox {
  width: 14px;
  height: 14px;
  border: 1.5px solid var(--border);
  border-radius: 3px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}

.country-item.selected .country-checkbox {
  background: var(--accent);
  border-color: var(--accent);
}

.country-item.selected .country-checkbox::after {
  content: '✓';
  color: white;
  font-size: 10px;
  font-weight: bold;
}

.country-info {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.country-name {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.country-bar-container {
  height: 4px;
  background: var(--border);
  border-radius: 2px;
  overflow: hidden;
}

.country-bar {
  height: 100%;
  border-radius: 2px;
  transition: width 0.3s;
}

.country-value {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  flex-shrink: 0;
}

/* Chart Area */
.chart-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.chart-container {
  position: relative;
  background: var(--bg-alt);
  border-radius: 8px;
  padding: 1rem;
  flex: 1;
}

#chart {
  width: 100%;
  height: 100%;
  display: block;
}

.country-label {
  font-size: 11px;
  font-weight: 500;
  transition: opacity 0.15s;
}

.country-label.dimmed {
  opacity: 0.2;
}

.chart-line {
  transition: opacity 0.15s;
}

.chart-line.dimmed {
  opacity: 0.15;
}

.chart-point {
  transition: opacity 0.15s;
}

.chart-point.dimmed {
  opacity: 0.15;
}

/* Chart Footer */
.chart-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 0.75rem;
  padding: 0 0.25rem;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.chart-legend {
  display: flex;
  gap: 1rem;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.8rem;
  color: var(--text-muted);
}

.legend-color {
  width: 16px;
  height: 2px;
  background: var(--text-muted);
}

.legend-color.dashed {
  background: repeating-linear-gradient(
    90deg,
    var(--text-muted) 0,
    var(--text-muted) 4px,
    transparent 4px,
    transparent 8px
  );
}

.chart-actions {
  display: flex;
  gap: 0.5rem;
}

.action-btn {
  display: flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.35rem 0.6rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--bg);
  font-size: 0.75rem;
  font-family: var(--font);
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.15s;
}

.action-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* Tooltip */
.tooltip {
  position: absolute;
  background: rgba(26, 26, 26, 0.95);
  color: white;
  padding: 0.5rem 0.75rem;
  border-radius: 6px;
  font-size: 0.8rem;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.15s;
  z-index: 50;
  max-width: 220px;
}

.tooltip.active {
  opacity: 1;
}

.tooltip-year {
  font-weight: 600;
  margin-bottom: 0.25rem;
  border-bottom: 1px solid rgba(255,255,255,0.2);
  padding-bottom: 0.25rem;
}

.tooltip-row {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.15rem 0;
}

.tooltip-country {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.tooltip-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}

.tooltip-value {
  font-family: var(--font-mono);
  font-size: 0.75rem;
}

.crosshair {
  stroke: var(--text-muted);
  stroke-width: 1;
  stroke-dasharray: 3, 3;
  opacity: 0.5;
}

/* FAQ Section */
.faq-section {
  margin-bottom: 3rem;
}

.faq-section h2 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

details {
  border-bottom: 1px solid var(--border);
}

details:first-of-type {
  border-top: 1px solid var(--border);
}

summary {
  padding: 1rem 0;
  cursor: pointer;
  font-weight: 500;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

summary::after {
  content: '−';
  font-size: 1.25rem;
  color: var(--text-muted);
}

details:not([open]) summary::after {
  content: '+';
}

summary::-webkit-details-marker {
  display: none;
}

details p {
  padding-bottom: 1rem;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.reference {
  font-size: 0.85rem;
  padding-bottom: 1rem;
}

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

.reference a:hover {
  text-decoration: underline;
}

/* Source Section */
.source-section {
  margin-bottom: 2rem;
}

.source-section h2 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

.source-info {
  background: var(--bg-alt);
  padding: 1rem;
  border-radius: 8px;
}

.source-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 0.75rem;
}

.source-item {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
}

.source-label {
  font-size: 0.7rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.source-value {
  font-size: 0.9rem;
}

.source-value a {
  color: var(--accent);
  text-decoration: none;
}

.source-value a:hover {
  text-decoration: underline;
}

.source-note {
  color: var(--text-muted);
  font-size: 0.85rem;
  font-style: italic;
  margin-top: 1rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--border);
}

/* Reuse Section */
.reuse-section {
  margin-bottom: 2rem;
}

.reuse-section h2 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
}

.reuse-section > p {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
}

.reuse-section a {
  color: var(--accent);
  text-decoration: none;
}

.reuse-section a:hover {
  text-decoration: underline;
}

.reuse-section h3 {
  font-size: 1rem;
  font-weight: 500;
  margin-bottom: 0.5rem;
}

.citation-box {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  background: var(--bg-alt);
  padding: 0.75rem 1rem;
  border-radius: 6px;
  flex-wrap: wrap;
}

.citation-box code {
  flex: 1;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text);
}

.copy-citation {
  padding: 0.35rem 0.75rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--bg);
  font-size: 0.8rem;
  font-family: var(--font);
  cursor: pointer;
  transition: all 0.15s;
}

.copy-citation:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* Footer */
footer {
  margin-top: 3rem;
  padding: 2rem 1rem 3rem;
  position: relative;
  background: var(--bg-alt);
  margin-left: -1rem;
  margin-right: -1rem;
  /* Extend gray background full width using box-shadow */
  box-shadow: 0 0 0 100vmax var(--bg-alt);
  clip-path: inset(0 -100vmax);
}

footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 100vw;
  height: 1px;
  background: var(--border);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 2rem;
  flex-wrap: wrap;
}

.footer-about {
  flex: 1;
  min-width: 280px;
  max-width: 600px;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
  font-size: 1rem;
  color: var(--accent);
  margin-bottom: 0.75rem;
}

.footer-about p {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.footer-about a {
  color: var(--accent);
  text-decoration: none;
}

.footer-about a:hover {
  text-decoration: underline;
}

.footer-links {
  display: flex;
  gap: 3rem;
}

.footer-column {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.footer-column-title {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text);
  margin-bottom: 0.25rem;
}

.footer-links a {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.85rem;
  transition: color 0.15s;
}

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

/* Page content (for static pages like changelog) */
.page-content {
  padding: 2rem 0 3rem;
}

.page-content h1 {
  font-size: 2rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.page-description {
  color: var(--text-muted);
  font-size: 1rem;
  margin-bottom: 2rem;
}

/* Article */
.article-content {
  max-width: 900px;
}

.article-content article {
  width: 100%;
}

.article-layout {
  display: flex;
  gap: 3rem;
}

.article-layout .article-body {
  flex: 1;
  max-width: 680px;
}

/* Article page - non-sticky main header */
body.article-page > header {
  position: relative;
  z-index: 1;
}

/* Article sticky nav bar */
.article-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
  opacity: 0;
  pointer-events: none;
}

.article-nav.visible {
  opacity: 1;
  pointer-events: auto;
}

.article-nav-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0.75rem 1rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.article-nav-title {
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--text);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.article-nav-cta {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.5rem 0.9rem;
  background: var(--accent);
  color: white;
  border: none;
  border-radius: 6px;
  font-size: 0.85rem;
  font-weight: 500;
  text-decoration: none;
  transition: background 0.15s;
  flex-shrink: 0;
}

.article-nav-cta:hover {
  background: var(--accent-hover);
}

/* Table of contents */
.toc {
  position: sticky;
  top: 5rem;
  width: 180px;
  flex-shrink: 0;
  align-self: flex-start;
  height: fit-content;
}

.toc-title {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 1.25rem;
}

.toc-list {
  list-style: none;
  padding: 0;
  margin: 0;
  padding-top: 0.5rem;
}

.toc-list li {
  margin-bottom: 0.5rem;
}

.toc-list a {
  display: block;
  font-size: 0.85rem;
  color: var(--text-muted);
  text-decoration: none;
  padding: 0.25rem 0;
  padding-left: 0.75rem;
  border-left: 2px solid var(--border);
  transition: all 0.15s;
}

.toc-list a:hover {
  color: var(--text);
}

.toc-list a.active {
  color: var(--accent);
  border-left-color: var(--accent);
  font-weight: 500;
}

.article-header {
  margin-bottom: 2rem;
  padding-bottom: 2rem;
  position: relative;
}

.article-header::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 100vw;
  height: 1px;
  background: var(--border);
}

.article-date {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}

.article-header h1 {
  font-size: 2.25rem;
  line-height: 1.2;
  margin-bottom: 1rem;
}

.article-subtitle {
  font-size: 1.15rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.article-body h2 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  scroll-margin-top: 5rem;
}

.article-body h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-top: 2rem;
  margin-bottom: 0.75rem;
}

.article-body p {
  margin-bottom: 1rem;
  line-height: 1.7;
  color: var(--text);
}

.article-body a {
  color: var(--accent);
  text-decoration: none;
}

.article-body a:hover {
  text-decoration: underline;
}

.article-body ul {
  margin-bottom: 1.5rem;
  padding-left: 1.5rem;
}

.article-body li {
  margin-bottom: 0.5rem;
  line-height: 1.6;
}

.article-body strong {
  font-weight: 600;
}

/* Tweet/Quote style */
.tweet-quote {
  background: var(--bg-alt);
  border-left: 3px solid var(--accent);
  padding: 1.25rem 1.5rem;
  margin: 1.5rem 0;
  border-radius: 0 8px 8px 0;
}

.tweet-quote p {
  font-size: 1.05rem;
  line-height: 1.6;
  margin-bottom: 0.75rem;
  color: var(--text);
}

.tweet-quote cite {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-style: normal;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.tweet-quote cite strong {
  color: var(--text);
}

.tweet-quote cite a {
  color: var(--accent);
  text-decoration: none;
}

.tweet-quote cite a:hover {
  text-decoration: underline;
}

.tweet-quote mark {
  background: rgba(16, 185, 129, 0.2);
  color: inherit;
  padding: 0.1em 0.2em;
  border-radius: 3px;
}

/* Comparison table */
.comparison-table-wrapper {
  overflow-x: auto;
  margin: 1.5rem 0 2rem;
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.comparison-table th,
.comparison-table td {
  padding: 0.75rem 0.5rem;
  text-align: center;
  border-bottom: 1px solid var(--border);
}

.comparison-table th {
  font-weight: 500;
  font-size: 0.8rem;
  color: var(--text-muted);
  background: var(--bg-alt);
}

.comparison-table th:first-child {
  text-align: left;
}

.comparison-table td.source-name {
  text-align: left;
  font-weight: 500;
}

.comparison-table td.yes::before {
  content: '';
  display: inline-block;
  width: 18px;
  height: 18px;
  background: var(--accent);
  border-radius: 50%;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='20 6 9 17 4 12'%3E%3C/polyline%3E%3C/svg%3E");
  background-size: 12px;
  background-position: center;
  background-repeat: no-repeat;
}

.comparison-table td.no::before {
  content: '';
  display: inline-block;
  width: 18px;
  height: 18px;
  background: #ef4444;
  border-radius: 50%;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cline x1='18' y1='6' x2='6' y2='18'%3E%3C/line%3E%3Cline x1='6' y1='6' x2='18' y2='18'%3E%3C/line%3E%3C/svg%3E");
  background-size: 10px;
  background-position: center;
  background-repeat: no-repeat;
}

.comparison-table tr.highlight-row {
  background: rgba(16, 185, 129, 0.08);
}

.comparison-table tr.highlight-row td.source-name {
  color: var(--accent);
  font-weight: 600;
}

/* Changelog */
.changelog-list {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.changelog-entry {
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border);
}

.changelog-entry:last-child {
  border-bottom: none;
}

.changelog-date {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}

.changelog-entry h2 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

.changelog-entry ul {
  padding-left: 1.5rem;
  color: var(--text-muted);
}

.changelog-entry li {
  margin-bottom: 0.5rem;
  font-size: 0.95rem;
}

.changelog-entry a {
  color: var(--accent);
  text-decoration: none;
}

.changelog-entry a:hover {
  text-decoration: underline;
}

/* Toast */
.toast {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  background: var(--text);
  color: white;
  padding: 0.75rem 1.25rem;
  border-radius: 6px;
  font-size: 0.85rem;
  opacity: 0;
  transition: opacity 0.2s;
  z-index: 1001;
}

.toast.active {
  opacity: 1;
}

/* Responsive */
@media (max-width: 900px) {
  .article-layout {
    flex-direction: column;
  }

  .toc {
    position: relative;
    top: 0;
    width: 100%;
    margin-bottom: 1.5rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid var(--border);
  }

  .toc-list {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem 1rem;
  }

  .toc-list li {
    margin-bottom: 0;
  }

  .toc-list a {
    border-left: none;
    padding-left: 0;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
  }

  .toc-list a.active {
    background: rgba(16, 185, 129, 0.1);
  }

  .article-layout .article-body {
    max-width: none;
  }
}

@media (max-width: 768px) {
  .chart-layout {
    flex-direction: column;
    min-height: auto;
  }

  .country-panel {
    width: 100%;
    max-height: none;
  }

  .country-list {
    max-height: 180px;
  }

  .chart-container {
    height: 350px;
    flex: none;
  }

  /* Hide TOC on mobile articles */
  .toc {
    display: none;
  }

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

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

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

  .comparison-table th,
  .comparison-table td {
    padding: 0.5rem 0.35rem;
  }
}

@media (max-width: 640px) {
  body {
    padding: 0 0.75rem 1.5rem;
  }

  h1 {
    font-size: 1.5rem;
  }

  .chart-actions {
    width: 100%;
    justify-content: flex-start;
  }

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

@media (max-width: 370px) {
  .view-count {
    display: none;
  }
}