/* Chart panel: axis, state groups, senator bars (vertical default). */

/* Chart panel */
.data-load-error {
  margin: 1.25rem 1rem;
  padding: 1rem 1.15rem;
  max-width: 36rem;
  border: 1px solid var(--border);
  background: var(--surface-2);
  color: var(--text-secondary);
  font-family: var(--font);
  font-size: 1rem;
  line-height: 1.45;
}

.data-load-error strong {
  display: block;
  margin-bottom: 0.35rem;
  color: var(--text);
  font-weight: 600;
}

.data-load-error p {
  margin: 0;
}

.data-load-error code {
  font-family: var(--mono);
  font-size: 1em;
}

.chart-panel {
  max-width: var(--page-max);
  margin: 0 auto;
  padding: 0;
}

/* Drawn horizontal scroller. Native chart bars stay hidden so this rail is the control. */
.timeline-xscroll {
  --xscroll-h: 20px;
  position: sticky;
  top: var(--header-h, 0px);
  z-index: 19;
  box-sizing: content-box;
  height: var(--xscroll-h);
  max-width: 100%;
  margin: 0;
  background: var(--border);
  overflow: hidden;
  touch-action: none;
}

.timeline-xscroll[hidden] {
  display: none;
}

.timeline-xscroll:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

.timeline-xscroll-step {
  position: absolute;
  top: 0;
  z-index: 2;
  height: var(--xscroll-h);
  margin: 0;
  padding: 0 0.4rem;
  border: 0;
  background: var(--border);
  color: var(--text);
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 600;
  line-height: var(--xscroll-h);
  letter-spacing: -0.06em;
  cursor: pointer;
  user-select: none;
}

.timeline-xscroll-step[data-scroll-dir="-1"] {
  left: 0;
}

.timeline-xscroll-step[data-scroll-dir="1"] {
  right: 0;
}

.timeline-xscroll-step:hover,
.timeline-xscroll-step:focus-visible {
  outline: none;
  background: var(--border-light);
  color: var(--text);
}

.timeline-xscroll-step.is-disabled {
  opacity: 0.35;
  cursor: default;
}

.timeline-xscroll-thumb {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 1;
  height: var(--xscroll-h);
  background: var(--accent);
  border-radius: 0;
  cursor: grab;
  touch-action: none;
}

.timeline-xscroll-thumb.is-dragging {
  cursor: grabbing;
}

.timeline-xscroll-thumb:hover,
.timeline-xscroll-thumb.is-dragging {
  background: color-mix(in srgb, var(--accent) 82%, var(--text));
}

.timeline-scroll-clip {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  max-width: 100%;
  margin-top: 0.25rem;
  border-radius: 8px;
  /* Sticky axis and labels otherwise paint over the rounded corners. */
  clip-path: inset(0 round 8px);
}

.chart-panel.is-overflowing .timeline-scroll-clip::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 2;
  pointer-events: none;
  background:
    linear-gradient(to right, color-mix(in srgb, var(--bg) 50%, transparent), transparent 2.75rem),
    linear-gradient(to left, color-mix(in srgb, var(--bg) 50%, transparent), transparent 2.75rem);
}

.chart-slide-hint {
  position: absolute;
  left: 0;
  right: 0;
  z-index: 3;
  height: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  pointer-events: none;
}

.chart-slide-hint[hidden] {
  display: none;
}

.chart-slide-hint-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.35rem;
  padding: 0.7rem 0.9rem;
  border-radius: 1.1rem;
  background: color-mix(in srgb, var(--chart-bg) 88%, transparent);
  box-shadow: 0 10px 28px color-mix(in srgb, var(--text) 22%, transparent);
  color: var(--text);
  font-family: var(--font);
  font-size: 1rem;
  line-height: 1.2;
  white-space: nowrap;
  animation: chart-slide-nudge 1.8s ease-in-out infinite;
}

.chart-slide-hint img {
  width: 4.75rem;
  height: auto;
}

@keyframes chart-slide-nudge {
  0%,
  100% {
    transform: translateX(-0.85rem);
  }
  50% {
    transform: translateX(0.85rem);
  }
}

@media (prefers-reduced-motion: reduce) {
  .chart-slide-hint-card {
    animation: none;
  }
}

[data-theme="dark"] .chart-slide-hint img {
  filter: invert(1);
}

body.is-exporting .chart-slide-hint,
body.is-exporting .chart-panel.is-overflowing .timeline-scroll-clip::before {
  display: none !important;
}

.chart-nav:has(.timeline-xscroll:not([hidden])) + .timeline-scroll-clip {
  margin-top: 0;
}

/* Overview strip and the sideways scroller. Both stick under the header. */
.chart-nav {
  position: sticky;
  top: var(--header-h, 0px);
  z-index: 19;
  background: var(--bg);
}

.chart-nav .timeline-xscroll {
  position: relative;
  top: auto;
}

.minimap {
  position: relative;
  z-index: 1;
  width: 100%;
  margin: 0;
  padding: 0;
}

.minimap[hidden] {
  display: none !important;
}

.minimap-frame {
  position: relative;
  overflow: hidden;
  line-height: 0;
  cursor: pointer;
  touch-action: none;
  user-select: none;
  background: var(--chart-bg);
  border: 1px solid var(--border);
}

.minimap-year {
  position: absolute;
  z-index: 3;
  top: 0;
  padding: 0.12rem 0.4rem 0.16rem;
  font-family: var(--font-chart);
  font-size: 1rem;
  font-weight: 600;
  font-feature-settings: "tnum" 1;
  line-height: 1.1;
  color: var(--text);
  background: color-mix(in srgb, var(--chart-bg) 88%, transparent);
  pointer-events: none;
}

.minimap-year-start {
  left: 0;
}

.minimap-year-end {
  right: 0;
}

.minimap-frame:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

.minimap-frame.is-dragging {
  cursor: grabbing;
}

.minimap-frame canvas {
  display: block;
  width: 100%;
}

.minimap-viewport {
  position: absolute;
  z-index: 1;
  box-sizing: border-box;
  min-width: 6px;
  min-height: 6px;
  border: 2px solid var(--text);
  box-shadow: 0 0 0 1px var(--chart-bg);
}

body.is-exporting .chart-nav,
body.is-exporting .minimap {
  display: none !important;
}

.timeline-scroll {
  /* Vertical: hug filtered content and center in the panel.
     The chart still scrolls; its own bar stays hidden. */
  position: relative;
  z-index: 1;
  width: max-content;
  max-width: 100%;
  overflow-x: auto;
  overflow-y: hidden;
  margin: 0 auto;
  border: none;
  background: var(--chart-bg);
  scrollbar-width: none;
}

.timeline-scroll::-webkit-scrollbar {
  display: none;
  width: 0;
  height: 0;
}



.timeline {
  min-width: max-content;
  min-height: max-content;
  position: relative;
}

.timeline-main {
  display: flex;
  align-items: flex-start;
  gap: var(--state-gap);
}

.chart-note {
  margin: 0.65rem 0 0;
  font-size: 1rem;
  color: var(--text-muted);
  letter-spacing: 0.02em;
}

/* Year axis (Y) + seat columns (X) */
.year-axis-col {
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  position: sticky;
  left: 0;
  z-index: 14;
  background: var(--chart-bg);
  box-shadow: var(--year-axis-shadow);
}

.axis-corner {
  display: block;
  flex-shrink: 0;
  position: sticky;
  top: 0;
  z-index: 16;
  width: var(--year-label-w);
  height: var(--label-h);
  padding: 0;
  overflow: hidden;
  background: var(--chart-bg);
  border-bottom: 1px solid var(--border-light);
  box-sizing: border-box;
}

/* Real SVG line — pseudo-element gradients with calc() are unreliable in export. */
.axis-corner-diag {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

.axis-corner-diag line {
  stroke: var(--border-light);
  stroke-width: 1;
  vector-effect: non-scaling-stroke;
}

.axis-corner-label {
  position: absolute;
  font-family: var(--font-chart);
  font-size: 1rem;
  font-weight: 600;
  font-feature-settings: "tnum" 1, "kern" 1;
  letter-spacing: var(--type-body-tracking);
  color: var(--text);
  line-height: 1;
  user-select: none;
}

.axis-corner-year {
  bottom: 0.4rem;
  left: 0.35rem;
  display: inline-flex;
  align-items: center;
  gap: 0.15rem;
}

/* Arrow points toward newer years (default glyph faces down). */
.axis-corner-year-arrow {
  display: block;
  width: 0.5rem;
  height: 0.5rem;
  flex-shrink: 0;
  color: inherit;
  transform-origin: center;
}

html[data-year-order="descending"] .axis-corner-year-arrow {
  transform: rotate(180deg);
}

html[data-orientation="horizontal"] .axis-corner-year-arrow {
  transform: rotate(-90deg);
}

html[data-orientation="horizontal"][data-year-order="descending"] .axis-corner-year-arrow {
  transform: rotate(90deg);
}

.axis-corner-country {
  top: 0.35rem;
  right: 0.35rem;
}

.year-axis {
  display: block;
  flex-shrink: 0;
  position: relative;
  width: var(--year-label-w);
  background: var(--chart-bg);
}

.axis-ticks {
  position: absolute;
  left: 0;
  top: 0;
  pointer-events: none;
  overflow: visible;
}

.axis-ticks line {
  shape-rendering: crispEdges;
}

.axis-ticks .tick-minor {
  stroke: var(--year-line-minor);
  stroke-width: 1;
}

.axis-ticks .tick-major {
  stroke: var(--year-line-major);
  stroke-width: 1;
}

.axis-ticks .tick-decade {
  stroke: var(--year-line-decade);
  stroke-width: 1.5;
}

.congress-mark {
  display: none;
  position: absolute;
  left: auto;
  right: 0;
  width: var(--congress-rail);
  z-index: 1;
  align-items: center;
  justify-content: center;
  box-sizing: border-box;
  font-family: var(--font-chart);
  font-size: 0.62rem;
  font-weight: 600;
  font-feature-settings: "tnum" 1;
  line-height: 1;
  color: var(--text-muted);
  pointer-events: auto;
  user-select: none;
  background: transparent;
}

/* Numbers sit in a rail beside the years so they do not cover year labels or ticks. */
html.congresses-enabled {
  --congress-rail: 28px;
  --year-label-w: 92px;
}

html.congresses-enabled .axis-year-label {
  right: var(--congress-rail);
}

html.congresses-enabled .congress-mark {
  display: flex;
}

.axis-year-label {
  position: absolute;
  z-index: 2;
  left: 0;
  right: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  box-sizing: border-box;
  font-family: var(--font-chart);
  font-size: 1rem;
  font-weight: 600;
  line-height: 1;
  text-align: center;
  user-select: none;
  font-feature-settings: "tnum" 1, "kern" 1;
  letter-spacing: var(--type-body-tracking);
  color: var(--text);
  pointer-events: none;
}

/* State groups (one label, two seat tracks) */
.state-group {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  flex-shrink: 0;
  background: var(--chart-bg);
}

.state-group:last-child {
  box-shadow: none;
}

.state-group.alt {
  background: var(--row-alt);
}

.state-group.hidden {
  display: none;
}

.state-seats {
  display: flex;
  flex-direction: row;
  align-items: flex-start;
  gap: var(--seat-gap);
  position: relative;
}

.congress-layer {
  display: none;
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
}

html.congresses-enabled .congress-layer {
  display: block;
}

.congress-band {
  position: absolute;
  left: 0;
  right: 0;
  background: var(--congress-band);
}

.event-markers {
  display: none;
  position: absolute;
  inset: 0;
  z-index: 2;
  pointer-events: none;
}

html.ussr-marker-enabled .event-markers {
  display: block;
}

.event-marker {
  position: absolute;
  pointer-events: none;
}

/* USSR dissolution: a solid repeating zigzag cut. Hard mask stops keep a single stroke. */
.event-marker-ussr {
  --a: 68deg;
  --s: 12px;
  --b: 5px;
  z-index: 2;
  background: var(--dissolution);
  opacity: var(--dissolution-opacity);
  overflow: visible;
}

html[data-orientation="horizontal"] .event-marker-ussr {
  top: 0;
  bottom: 0;
  width: calc(var(--b) + var(--s) / (2 * tan(var(--a) / 2)));
  min-width: 7px;
  transform: translateX(-50%);
  --_g: 100% var(--s) repeat-y conic-gradient(
    from calc(90deg - var(--a) / 2) at left,
    #0000 0deg,
    #000 0.2deg calc(var(--a) - 0.2deg),
    #0000 var(--a)
  );
  -webkit-mask: var(--b) 50% / var(--_g) exclude, 0 50% / var(--_g);
  mask: var(--b) 50% / var(--_g) exclude, 0 50% / var(--_g);
}

html[data-orientation="vertical"] .event-marker-ussr {
  left: 0;
  right: 0;
  height: calc(var(--b) + var(--s) / (2 * tan(var(--a) / 2)));
  min-height: 7px;
  transform: translateY(-50%);
  --_g: var(--s) 100% repeat-x conic-gradient(
    from calc(var(--a) / -2) at top,
    #0000 0deg,
    #000 0.2deg calc(var(--a) - 0.2deg),
    #0000 var(--a)
  );
  -webkit-mask: 50% var(--b) / var(--_g) exclude, 50% 0 / var(--_g);
  mask: 50% var(--b) / var(--_g) exclude, 50% 0 / var(--_g);
}

.marker {
  position: absolute;
  z-index: 5;
  pointer-events: auto;
  cursor: help;
}

.marker.sovereignty,
.marker.independence {
  display: none;
}

html.sovereignty-markers-enabled .marker.sovereignty,
html.independence-markers-enabled .marker.independence {
  display: block;
}

.marker.sovereignty {
  background: var(--sovereignty);
  box-shadow: 0 0 0 1px var(--sovereignty-edge);
}

.marker.independence {
  background: var(--independence);
  box-shadow: 0 0 0 1px var(--independence-edge);
}

html[data-orientation="horizontal"] .marker {
  top: 4px;
  bottom: 4px;
  width: 3px;
  transform: translateX(-50%);
}

html[data-orientation="horizontal"] .marker::before {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: -6px;
  right: -6px;
}

html[data-orientation="vertical"] .marker {
  left: 3px;
  right: 3px;
  height: 3px;
  transform: translateY(-50%);
}

html[data-orientation="vertical"] .marker::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: -6px;
  bottom: -6px;
}

.event-marker-label {
  position: absolute;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--text-muted);
  white-space: nowrap;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  padding: 0.05rem 0.28rem;
  border-radius: 3px;
}

html[data-orientation="horizontal"] .event-marker-label {
  top: 0.35rem;
  left: calc(100% + 0.35rem);
}

html[data-orientation="vertical"] .event-marker-label {
  top: calc(100% + 0.15rem);
  left: 0.45rem;
}

.country-row {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  flex-shrink: 0;
  width: var(--seat-w);
}

.country-label {
  width: 100%;
  height: var(--label-h);
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.15rem;
  padding: 0.35rem 0.15rem;
  font-size: 1rem;
  font-weight: 500;
  position: sticky;
  top: 0;
  background: inherit;
  z-index: 12;
  border-bottom: 1px solid var(--border);
  box-shadow: var(--label-shadow);
  box-sizing: border-box;
  overflow: visible;
}

.state-group.alt .country-label {
  background: var(--chart-bg-alt);
}

.state-group:not(.alt) .country-label {
  background: var(--chart-bg);
}

/* Transform-only vertical text - writing-mode is unreliable in export. */
.country-name {
  position: absolute;
  left: 50%;
  top: 50%;
  width: calc(var(--label-h) - 8px);
  font-family: var(--font-chart);
  color: var(--text);
  letter-spacing: normal;
  line-height: 1;
  font-size: 1rem;
  font-weight: 600;
  font-feature-settings: normal;
  text-align: center;
  text-transform: uppercase;
  white-space: nowrap;
  overflow: visible;
  transform: translate(-50%, -50%) rotate(-90deg);
  transform-origin: center center;
}

.country-label:has(.country-admitted) .country-name {
  left: 34%;
  top: 50%;
}

.country-admitted {
  position: absolute;
  left: 72%;
  top: 50%;
  font-family: var(--font-chart);
  font-size: 1rem;
  font-weight: 600;
  font-feature-settings: "tnum" 1, "kern" 1;
  letter-spacing: var(--type-body-tracking);
  line-height: 1;
  text-align: center;
  color: var(--text);
  white-space: nowrap;
  pointer-events: auto;
  transform: translate(-50%, -50%) rotate(-90deg);
  transform-origin: center center;
}

html.admission-year-hidden .country-admitted {
  display: none;
}

/* Year gone - re-center the state name in the label strip. */
html.admission-year-hidden .country-label:has(.country-admitted) .country-name {
  left: 50%;
}

.country-track {
  position: relative;
  flex: 0 0 auto;
  width: var(--seat-w);
  background-image:
    repeating-linear-gradient(
      to bottom,
      var(--year-line-decade) 0,
      var(--year-line-decade) 1.5px,
      transparent 1.5px,
      transparent calc(10 * var(--year-h))
    ),
    repeating-linear-gradient(
      to bottom,
      var(--year-line-major) 0,
      var(--year-line-major) 1px,
      transparent 1px,
      transparent calc(5 * var(--year-h))
    ),
    repeating-linear-gradient(
      to bottom,
      var(--year-line-minor) 0,
      var(--year-line-minor) 1px,
      transparent 1px,
      transparent var(--year-h)
    );
  background-repeat: no-repeat, no-repeat, no-repeat;
  background-size: var(--year-tick) 100%, var(--year-tick) 100%, var(--year-tick) 100%;
  background-position-x: center, center, center;
  background-position-y:
    var(--grid-decade-offset, 0),
    var(--grid-major-offset, 0),
    0;
}

.state-group .country-row:last-child .country-track {
  border-right: none;
}

.year-grid,
.year-cell {
  display: none;
}

/* Bars */
.bar {
  position: absolute;
  border-radius: var(--bar-radius);
  cursor: default;
  min-height: 2px;
}

.bar.dimmed {
  opacity: 0.28;
}

.bar.focused {
  opacity: 1;
  outline: 1px solid color-mix(in srgb, var(--accent) 55%, transparent);
}

.bar.selected {
  opacity: 1;
  outline: none;
}

/* Quiet dashed edge and a few thin hatch strokes. */
.bar.selected::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  box-sizing: border-box;
  pointer-events: none;
  z-index: 1;
  border: 1px dashed var(--bar-select-stroke, rgba(255, 255, 255, 0.7));
  background: repeating-linear-gradient(
    -45deg,
    transparent 0 8px,
    var(--bar-select-hatch, rgba(255, 255, 255, 0.38)) 8px 9px
  );
}

.bar.ruler {
  left: var(--ruler-inset);
  width: var(--ruler-width);
  border: none;
  z-index: 3;
  cursor: pointer;
}

.bar.ruler.split-lane {
  box-shadow: inset 0 0 0 1px color-mix(in srgb, var(--chart-bg) 55%, transparent);
}

/* Continuous stepped reign: full track when alone, narrow only while contested. */
.bar.ruler.stepped {
  border-radius: 0;
  overflow: visible;
  pointer-events: none;
  /* Override fixed seat inset/width from .bar.ruler — bbox comes from the path. */
  left: 0;
  width: auto;
}

.bar.ruler.stepped .bar-step-svg {
  position: absolute;
  inset: 0;
  display: block;
  pointer-events: none;
  overflow: visible;
}

.bar.ruler.stepped .bar-step-path {
  pointer-events: fill;
  cursor: pointer;
}

.bar.ruler.stepped.selected::after {
  border-radius: 0;
  /* Hatch follows the step, while the name is allowed to cross slices. */
  inset: 0;
  clip-path: var(--step-clip);
}

.bar-label.dimmed {
  opacity: 0.28;
}

.bar.ruler.focused {
  z-index: 6;
}

.bar.ruler.selected {
  z-index: 8;
}

/* Lift the seat track / state so a search outline paints over neighbors */
.country-track:has(.bar.focused) {
  z-index: 4;
}

.country-track:has(.bar.selected) {
  z-index: 5;
}

.state-group:has(.bar.focused) {
  position: relative;
  z-index: 2;
}

.state-group:has(.bar.selected) {
  position: relative;
  z-index: 3;
}

.bar-label {
  position: absolute;
  z-index: 2;
  left: 50%;
  /* Bottom to top, same as the state names. Pin to the past/start end of the bar. */
  transform: translateX(-50%) rotate(180deg);
  max-height: calc(100% - 8px);
  max-width: calc(100% - 2px);
  overflow: hidden;
  pointer-events: none;
  line-height: 0;
  writing-mode: vertical-rl;
  text-orientation: sideways;
  /* Default descending: present at top → start of term at bottom */
  top: auto;
  bottom: 4px;
}

/* Ascending: past at top → start of term at top */
html[data-year-order="ascending"] .bar-label {
  top: 4px;
  bottom: auto;
}

html.bar-labels-hidden .bar-label {
  display: none !important;
}

html.bar-labels-hidden .settings-nest:has(#short-bar-labels) {
  display: none;
}

html[data-color-mode="person"] label:has(#show-party-detail) {
  display: none;
}

html.ruler-bars-hidden .bar.ruler {
  background: transparent !important;
}

html.ruler-bars-hidden .bar.ruler.selected {
  background: transparent !important;
}

html.ruler-bars-hidden.bar-labels-hidden .legend-group-party,
html.ruler-bars-hidden.bar-labels-hidden .legend-group-person {
  display: none;
}

.bar-label-text {
  display: inline-block;
  max-width: 100%;
  max-height: 100%;
  padding: 4px 1px;
  border-radius: 0;
  font-family: var(--font-chart);
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  line-height: 1.2;
  color: var(--bar-label-fixed-fg);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  font-feature-settings: "kern" 1, "liga" 1;
}

.timeline-body {
  position: relative;
  display: flex;
  flex-direction: row;
  align-items: flex-start;
  gap: var(--state-gap);
}

/* Narrow screens: the year column scrolls with the chart instead of covering it. */
@media (max-width: 640px) {
  .year-axis-col {
    position: static;
    left: auto;
    box-shadow: none;
  }
}