/* ============================================================
   Paper Browser — base tokens, paper theme, shared rules
   ============================================================ */

:root {
  --scale: 1;
  --sanitary-half: 10px;
  --hud-height: 48px;
  --split-left: 50%;

  --font-serif: Georgia, "Times New Roman", serif;
  --font-mono: "JetBrains Mono", "SF Mono", Consolas, monospace;

  /* Timeline (scale-aware) */
  --font-year: calc(11px * var(--scale));
  --font-item: calc(14px * var(--scale));
  --font-item-sub: calc(11px * var(--scale));

  /* Article pane (NOT scale-aware) */
  --font-article-title: 34px;
  --font-article-description: 16px;
  --font-article-body: 16px;

  /* HUD (chrome) */
  --font-hud: 12px;

  /* Reference marks (fixed) */
  --font-axis-year: 9px;
  --font-conn-year: 9px;

  /* Paper theme */
  --paper: #f5efe0;
  --paper-raised: #faf5e8;
  --paper-edge: #dcd4c0;
  --ink: #2a2620;
  --ink-muted: #6a5f50;
  --ink-faint: #9e9179;
  --rule: #aa9f86;
  --relation: #6b3a2a;
  --highlight: #c77b4a;
}

/* ============================================================
   Reset + base
   ============================================================ */

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-serif);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
}

a { color: inherit; }

/* ============================================================
   HUD
   ============================================================ */

#hud {
  height: var(--hud-height);
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 0 12px;
  background: var(--paper-raised);
  border-bottom: 1px solid var(--paper-edge);
  font-size: var(--font-hud);
  color: var(--ink-muted);
  letter-spacing: 0.02em;
  z-index: 100;
}

.hud-logo {
  font-family: var(--font-serif);
  font-size: 14px;
  font-style: italic;
  color: var(--ink);
  text-decoration: none;
  letter-spacing: 0.01em;
}

.hud-logo:hover { color: var(--highlight); }

.hud-spacer { flex: 1 1 auto; }

.hud-stats {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--ink-faint);
  white-space: nowrap;
}

.hud-scale {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 0 4px;
  border: 1px solid var(--paper-edge);
  border-radius: 4px;
  background: var(--paper);
}

.hud-scale-label {
  font-family: var(--font-mono);
  font-size: 11px;
  min-width: 38px;
  text-align: center;
  color: var(--ink-muted);
}

.hud-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 28px;
  min-width: 28px;
  padding: 0 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ink-muted);
  border-radius: 4px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.hud-btn:hover {
  background: var(--paper);
  color: var(--ink);
}

.hud-save {
  border: 1px solid var(--paper-edge);
}

#hud-tabs {
  display: none;
  gap: 4px;
}

#hud-tabs .tab {
  padding: 4px 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--ink-faint);
  border-bottom: 2px solid transparent;
}

#hud-tabs .tab.active {
  color: var(--ink);
  border-color: var(--highlight);
}

/* ============================================================
   Split layout
   ============================================================ */

#split {
  flex: 1 1 auto;
  display: grid;
  grid-template-columns: var(--split-left) 8px 1fr;
  grid-template-rows: 1fr;
  height: calc(100vh - var(--hud-height));
  overflow: hidden;
}

#timeline-pane {
  position: relative;
  overflow-x: hidden;
  overflow-y: auto;
  background: var(--paper);
}

#article-pane {
  overflow-y: auto;
  background: var(--paper-raised);
  border-left: 1px solid var(--paper-edge);
}

#split-divider {
  background: var(--paper-edge);
  cursor: col-resize;
  transition: background 120ms;
}

#split-divider:hover {
  background: var(--ink-faint);
}

/* ============================================================
   Timeline SVG
   ============================================================ */

#stage {
  display: block;
  width: 100%;
  touch-action: none;
  user-select: none;
  -webkit-user-select: none;
}

.axis-line {
  stroke: var(--ink);
  stroke-width: 1.3px;
  opacity: 0.8;
}

.grid-major-line {
  stroke: var(--ink-faint);
  stroke-width: 1px;
  opacity: 0.28;
}

.grid-minor-line {
  stroke: var(--rule);
  stroke-width: 1px;
  opacity: 0.18;
}

.grid-micro-line {
  stroke: var(--rule);
  stroke-width: 1px;
  opacity: 0.07;
}

.year-label {
  font-family: var(--font-mono);
  font-size: 11px;
  fill: var(--ink-faint);
  opacity: 0.6;
}

.axis-year-label {
  font-family: var(--font-mono);
  font-size: var(--font-axis-year);
  fill: var(--ink-muted);
  opacity: 0.7;
  paint-order: stroke fill;
  stroke: var(--paper);
  stroke-width: 3px;
  stroke-linejoin: round;
}

.connector-year {
  font-family: var(--font-mono);
  font-size: var(--font-conn-year);
  fill: var(--ink-muted);
  opacity: 0.7;
  paint-order: stroke fill;
  stroke: var(--paper);
  stroke-width: 3px;
  stroke-linejoin: round;
}

/* Item marker */
.item-marker {
  fill: var(--ink);
  stroke: var(--ink);
  stroke-width: 1px;
  cursor: pointer;
}

.item-marker.current-item {
  fill: var(--highlight);
  stroke: var(--highlight);
  stroke-width: 1.5px;
}

.range-bar {
  fill: var(--ink);
  fill-opacity: 0.12;
  stroke: var(--ink);
  stroke-width: 1px;
  cursor: pointer;
}

.range-bar.current-item {
  fill: var(--highlight);
  fill-opacity: 0.2;
  stroke: var(--highlight);
  stroke-width: 1.5px;
}

.item-connector {
  stroke: var(--ink-faint);
  stroke-width: 1px;
  stroke-dasharray: 2 3;
  opacity: 0.8;
  pointer-events: none;
}

.item-connector.fading {
  stroke-dasharray: 1 4;
}

.item-title {
  font-family: var(--font-serif);
  font-size: var(--font-item);
  fill: var(--ink);
  cursor: pointer;
  paint-order: stroke fill;
  stroke: var(--paper);
  stroke-width: 3px;
  stroke-linejoin: round;
}

.item-subtitle {
  font-family: var(--font-serif);
  font-size: var(--font-item-sub);
  font-style: italic;
  fill: var(--ink-muted);
  cursor: pointer;
  paint-order: stroke fill;
  stroke: var(--paper);
  stroke-width: 3px;
  stroke-linejoin: round;
}

.item-recent-indicator {
  font-family: var(--font-mono);
  font-size: 9px;
  fill: var(--ink-faint);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  pointer-events: none;
}

.item-pin-indicator {
  font-family: var(--font-serif);
  font-size: calc(12px * var(--scale));
  fill: var(--highlight);
  pointer-events: none;
}

.item-primary-label {
  font-family: var(--font-mono);
  font-size: 9px;
  fill: var(--highlight);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  pointer-events: none;
}

.relation-path {
  fill: none;
  stroke: var(--relation);
  stroke-width: 1.2px;
  stroke-linecap: round;
  stroke-linejoin: round;
  pointer-events: none;
}

.relation-path.relation-dim {
  opacity: 0.35;
  stroke-width: 1px;
}

/* ============================================================
   Article pane
   ============================================================ */

.article-chrome {
  position: sticky;
  top: 0;
  background: var(--paper-raised);
  border-bottom: 1px solid var(--paper-edge);
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 8px 20px;
  z-index: 10;
}

.article-back {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-muted);
  padding: 4px 8px;
  border-radius: 4px;
}

.article-back:hover {
  background: var(--paper);
  color: var(--ink);
}

.article-external {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ink-muted);
  text-decoration: none;
}

.article-external:hover { color: var(--highlight); }

.article-body {
  font-family: var(--font-serif);
  font-size: var(--font-article-body);
  line-height: 1.6;
  color: var(--ink);
  max-width: 720px;
  margin: 0 auto;
  padding: 24px 24px 96px;
}

.article-body h1.article-title {
  font-size: var(--font-article-title);
  font-weight: 700;
  margin: 12px 0 8px;
  line-height: 1.15;
  letter-spacing: -0.01em;
}

.article-body p.article-description {
  font-size: var(--font-article-description);
  font-style: italic;
  color: var(--ink-muted);
  margin: 0 0 24px;
}

.article-hero {
  margin: 0 0 24px;
  text-align: center;
}

.article-hero img {
  max-width: 100%;
  height: auto;
  border: 1px solid var(--paper-edge);
  background: var(--paper);
}

.article-body h2 {
  font-size: 22px;
  font-weight: 600;
  margin: 32px 0 12px;
  padding-bottom: 4px;
  border-bottom: 1px solid var(--paper-edge);
}

.article-body h3 { font-size: 18px; margin: 24px 0 8px; }
.article-body h4 { font-size: 16px; margin: 20px 0 6px; }

.article-body p { margin: 0 0 14px; }

.article-body a {
  color: var(--highlight);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
}

.article-body a:visited { color: var(--ink-muted); }

.article-body img {
  max-width: 100%;
  height: auto;
}

.article-body figure {
  margin: 16px 0;
  text-align: center;
}

.article-body figcaption {
  font-size: 13px;
  color: var(--ink-muted);
  font-style: italic;
  margin-top: 4px;
}

.article-body table {
  border-collapse: collapse;
  margin: 16px 0;
  max-width: 100%;
  font-size: 14px;
}

.article-body table th,
.article-body table td {
  border: 1px solid var(--paper-edge);
  padding: 6px 10px;
  vertical-align: top;
  text-align: left;
}

.article-body table th {
  background: var(--paper);
  font-weight: 600;
}

.article-table-wrap {
  overflow-x: auto;
  margin: 16px 0;
}

.article-body ul,
.article-body ol {
  margin: 0 0 14px 0;
  padding-left: 24px;
}

.article-body li { margin-bottom: 4px; }

.article-body blockquote {
  border-left: 3px solid var(--highlight);
  margin: 14px 0;
  padding: 4px 16px;
  color: var(--ink-muted);
  font-style: italic;
}

.article-body code,
.article-body pre {
  font-family: var(--font-mono);
  font-size: 13px;
  background: var(--paper);
  border: 1px solid var(--paper-edge);
  border-radius: 3px;
}

.article-body code { padding: 1px 4px; }
.article-body pre {
  padding: 8px 12px;
  overflow-x: auto;
  margin: 14px 0;
}

.article-infobox {
  float: right;
  margin: 0 0 14px 20px;
  padding: 10px 14px;
  border: 1px solid var(--paper-edge);
  background: var(--paper);
  max-width: 280px;
  font-size: 13px;
}

@media (max-width: 640px) {
  .article-infobox { float: none; margin: 14px 0; max-width: 100%; }
}

.article-infobox dl { margin: 0; }
.article-infobox dt { font-weight: 600; color: var(--ink-muted); }
.article-infobox dd { margin: 0 0 8px 0; }

.article-bottom-link {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--paper-edge);
  text-align: center;
  font-size: 14px;
}

/* Skeleton */
.article-skeleton {
  padding: 24px;
  max-width: 720px;
  margin: 0 auto;
}

.skel {
  background: var(--paper-edge);
  border-radius: 3px;
  animation: skel-shimmer 1.4s ease-in-out infinite;
  margin-bottom: 10px;
}

.skel-title { height: 32px; width: 60%; }
.skel-desc { height: 14px; width: 80%; }
.skel-line { height: 14px; }
.skel-line.short { width: 70%; }

@keyframes skel-shimmer {
  0%, 100% { opacity: 0.35; }
  50% { opacity: 0.7; }
}

.article-error {
  padding: 48px 24px;
  max-width: 560px;
  margin: 0 auto;
  text-align: center;
}

.article-error h2 {
  font-size: 20px;
  margin: 0 0 12px;
  color: var(--ink-muted);
}

.article-error p {
  color: var(--ink-muted);
  margin-bottom: 16px;
}

.article-error button {
  padding: 8px 20px;
  border: 1px solid var(--paper-edge);
  border-radius: 4px;
  font-size: 13px;
  background: var(--paper);
}

.article-error button:hover {
  border-color: var(--ink-muted);
}

/* ============================================================
   Home view
   ============================================================ */

.home-view {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: 80px 24px;
  min-height: 100%;
}

.home-inner {
  max-width: 480px;
  width: 100%;
  text-align: center;
}

.home-title {
  font-family: var(--font-serif);
  font-size: 38px;
  font-weight: 600;
  margin: 0 0 8px;
  letter-spacing: -0.01em;
}

.home-tagline {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 16px;
  color: var(--ink-muted);
  margin: 0 0 32px;
}

.home-search {
  position: relative;
  margin: 0 0 32px;
}

.home-input {
  width: 100%;
  font-family: var(--font-serif);
  font-size: 16px;
  padding: 12px 16px;
  border: 1px solid var(--paper-edge);
  background: var(--paper-raised);
  color: var(--ink);
  border-radius: 4px;
  outline: none;
}

.home-input:focus {
  border-color: var(--highlight);
}

.home-suggest {
  position: absolute;
  left: 0;
  right: 0;
  top: calc(100% + 4px);
  background: var(--paper-raised);
  border: 1px solid var(--paper-edge);
  border-radius: 4px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
  max-height: 280px;
  overflow-y: auto;
  z-index: 5;
  text-align: left;
}

.home-suggest button {
  display: block;
  width: 100%;
  text-align: left;
  padding: 8px 14px;
  font-family: var(--font-serif);
  font-size: 14px;
  border-bottom: 1px solid var(--paper-edge);
}

.home-suggest button:last-child { border-bottom: 0; }

.home-suggest button:hover,
.home-suggest button.active {
  background: var(--paper);
  color: var(--highlight);
}

.home-tryhead {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 8px;
}

.home-try {
  display: flex;
  flex-direction: column;
  gap: 6px;
  align-items: center;
}

.home-try a {
  font-family: var(--font-serif);
  font-size: 15px;
  color: var(--ink);
  text-decoration: none;
  padding: 4px 8px;
}

.home-try a:hover {
  color: var(--highlight);
  text-decoration: underline;
}

/* ============================================================
   Modal
   ============================================================ */

.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(20, 16, 10, 0.4);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 200;
}

.modal {
  background: var(--paper-raised);
  border: 1px solid var(--paper-edge);
  border-radius: 8px;
  padding: 28px 32px;
  max-width: 480px;
  width: calc(100% - 40px);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.25);
}

.modal h2 {
  margin: 0 0 8px;
  font-size: 20px;
  font-family: var(--font-serif);
}

.modal p {
  color: var(--ink-muted);
  font-size: 14px;
  margin: 0 0 14px;
}

.save-url-input {
  width: 100%;
  font-family: var(--font-mono);
  font-size: 12px;
  padding: 8px 10px;
  border: 1px solid var(--paper-edge);
  background: var(--paper);
  color: var(--ink);
  border-radius: 4px;
  margin-bottom: 10px;
  outline: none;
}

.save-copy,
.modal-close {
  padding: 6px 14px;
  font-size: 12px;
  border: 1px solid var(--paper-edge);
  border-radius: 4px;
  background: var(--paper);
  margin-right: 8px;
}

.save-copy:hover,
.modal-close:hover {
  border-color: var(--ink-muted);
}

.save-hint {
  font-size: 12px;
  color: var(--ink-faint);
  margin-top: 6px;
}

/* ============================================================
   Mobile — tabs replace split
   ============================================================ */

@media (max-width: 900px) {
  #split {
    grid-template-columns: 1fr;
  }
  #split-divider { display: none; }
  #timeline-pane,
  #article-pane {
    grid-column: 1;
    grid-row: 1;
  }
  #timeline-pane { display: none; }
  #article-pane { display: block; }
  body.mobile-tab-timeline #timeline-pane { display: block; }
  body.mobile-tab-timeline #article-pane { display: none; }
  #hud-tabs { display: inline-flex !important; }
  #hud-tabs[hidden] { display: inline-flex !important; }
}