/*
 * The visual design of the service.
 *
 * The palette is a single dark theme. Colour carries meaning in the graph
 * and in the tables, so the variables are named by role rather than by hue.
 */

:root {
  color-scheme: dark;

  --background: #0b0f17;
  --surface: #121826;
  --surface-raised: #18202f;
  --border: #243044;
  --border-strong: #35455f;

  --text: #dfe7f1;
  --text-muted: #93a2b8;
  --text-faint: #64748b;

  --accent: #7fd1ff;
  --accent-strong: #4cb4e8;
  --accent-soft: rgba(127, 209, 255, 0.12);

  --positive: #5fd39a;
  --warning: #e8c26a;
  --negative: #f28b82;

  --group-overview: #7fd1ff;
  --group-time: #b8a2ff;
  --group-geometry: #5fd39a;
  --group-elements: #e8c26a;
  --group-propagation: #f28b82;
  --group-methods: #93a2b8;
  --group-input: #93a2b8;
  --group-prepare: #b8a2ff;
  --group-branch: #e8c26a;
  --group-propagate: #7fd1ff;
  --group-verify: #5fd39a;
  --group-fields: #5fd39a;
  --group-crosscheck: #e8c26a;
  --group-error: #f28b82;
  --group-output: #5fd39a;
  --group-validate: #b8a2ff;
  --group-convert: #7fd1ff;
  --group-store: #b8a2ff;
  --group-frames: #5fd39a;
  --group-rotate: #7fd1ff;
  --group-geodetic: #e8c26a;

  --radius: 8px;
  --radius-small: 5px;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
  --sidebar-width: 19rem;
  --toc-width: 15rem;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  height: 100%;
}

body {
  background: var(--background);
  color: var(--text);
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

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

a:hover {
  text-decoration: underline;
}

h1,
h2,
h3,
h4 {
  line-height: 1.25;
  font-weight: 600;
}

h1 {
  font-size: 1.9rem;
  margin: 0 0 0.5rem;
}

h2 {
  font-size: 1.35rem;
  margin: 2.25rem 0 0.75rem;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid var(--border);
}

h3 {
  font-size: 1.1rem;
  margin: 1.75rem 0 0.5rem;
}

h4 {
  font-size: 1rem;
  margin: 1.25rem 0 0.4rem;
  color: var(--text-muted);
}

p {
  margin: 0.75rem 0;
}

ul,
ol {
  margin: 0.75rem 0;
  padding-left: 1.5rem;
}

li {
  margin: 0.3rem 0;
}

code {
  font-family: var(--mono);
  font-size: 0.88em;
  background: var(--surface-raised);
  padding: 0.12em 0.35em;
  border-radius: var(--radius-small);
}

pre {
  margin: 0;
  overflow-x: auto;
}

pre code {
  background: none;
  padding: 0;
  font-size: 0.85rem;
  line-height: 1.6;
}

blockquote {
  margin: 1rem 0;
  padding: 0.25rem 1rem;
  border-left: 3px solid var(--border-strong);
  color: var(--text-muted);
}

hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 2rem 0;
}

/* Layout */

.app {
  display: flex;
  min-height: 100vh;
}

/* The frame carries the surface and the rule, so the column is drawn for
   the whole page. The sidebar itself is sticky and scrolls; without the
   frame the column would end one viewport down and look cut off on a long
   page. */
.sidebar-frame {
  flex: 0 0 var(--sidebar-width);
  background: var(--surface);
  border-right: 1px solid var(--border);
}

.sidebar {
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
  padding: 1.25rem 0 2rem;
}

.sidebar-brand {
  display: block;
  padding: 0 1.25rem 1rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 1rem;
}

.sidebar-brand a {
  color: var(--text);
  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: 0.01em;
}

.sidebar-brand p {
  margin: 0.15rem 0 0;
  color: var(--text-faint);
  font-size: 0.78rem;
}

.sidebar nav {
  padding: 0 0.75rem;
}

.sidebar-section {
  margin-bottom: 1.5rem;
}

.sidebar-section h2 {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-faint);
  margin: 0 0 0.5rem 0.5rem;
  border: none;
  padding: 0;
}

.sidebar-chapter {
  margin-bottom: 0.75rem;
}

.sidebar-chapter-title {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin: 0 0 0.2rem 0.5rem;
  font-weight: 600;
}

.sidebar a.item {
  display: block;
  padding: 0.3rem 0.5rem;
  border-radius: var(--radius-small);
  color: var(--text-muted);
  font-size: 0.88rem;
}

.sidebar a.item:hover {
  background: var(--surface-raised);
  color: var(--text);
  text-decoration: none;
}

.sidebar a.item.active {
  background: var(--accent-soft);
  color: var(--accent);
}

.main {
  flex: 1 1 auto;
  min-width: 0;
  display: flex;
  flex-direction: column;
}

.topbar {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1.5rem;
  border-bottom: 1px solid var(--border);
  background: rgba(11, 15, 23, 0.9);
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(6px);
}

.search-box {
  flex: 0 1 auto;
  max-width: 34rem;
  display: flex;
  gap: 0.5rem;
  align-items: stretch;
}

.search-box input {
  flex: 1 1 auto;
  /* Without this the input keeps its intrinsic width as its minimum and
     squeezes the button until the label wraps. */
  min-width: 0;
}

/* A button label is a single line; a narrow flex item must not break it. */
button {
  white-space: nowrap;
  flex-shrink: 0;
}

.content {
  padding: 1.75rem 2.5rem 4rem;
  width: 100%;
  flex: 1 1 auto;
}

/* A document is a measure of text plus the table of contents beside it, so
   the reading column keeps a comfortable line length while the table of
   contents sits at its right. The width is capped so that the pair stays
    centred on a very wide screen rather than drifting apart. */
.content.doc {
  max-width: calc(62rem + var(--toc-width) + 2.5rem);
  margin: 0 auto;
}

/* The graph and the crate grid use the whole width; a wide screen shows
   more of them rather than more margin. */
.content.wide {
  max-width: none;
}

/* Controls */

input,
select,
textarea,
button {
  font-family: inherit;
  font-size: 0.9rem;
}

input[type='text'],
input[type='number'],
input[type='search'],
select,
textarea {
  width: 100%;
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius-small);
  padding: 0.45rem 0.6rem;
  transition: border-color 0.12s ease;
}

input:focus,
select:focus,
textarea:focus {
  outline: none;
  border-color: var(--accent-strong);
}

textarea {
  font-family: var(--mono);
  font-size: 0.82rem;
  line-height: 1.5;
  resize: vertical;
  min-height: 6rem;
}

button {
  background: var(--accent-strong);
  color: #04121c;
  border: none;
  border-radius: var(--radius-small);
  padding: 0.45rem 0.9rem;
  font-weight: 600;
  cursor: pointer;
}

button:hover:not(:disabled) {
  background: var(--accent);
}

button:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

button.secondary {
  background: var(--surface-raised);
  color: var(--text);
  border: 1px solid var(--border-strong);
}

button.secondary:hover:not(:disabled) {
  background: var(--border);
}

button.ghost {
  background: none;
  color: var(--text-muted);
  border: 1px solid var(--border);
}

button.ghost:hover:not(:disabled) {
  background: var(--surface-raised);
  color: var(--text);
}

/* Cards and panels */

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.1rem 1.25rem;
}

.card + .card {
  margin-top: 1rem;
}

/* A filter field is a control, not a paragraph, so it is given a measure
   rather than the whole width of the page. */
.filter-field {
  max-width: 34rem;
}

.card h3 {
  margin-top: 0;
}

/* A grid of cards stretches every card in a row to the height of the
   tallest. The card is a column so that its action sits at the bottom of
   every card rather than floating at the height of the text above it. */
.grid.cards > .card {
  display: flex;
  flex-direction: column;
  height: 100%;
}

.card-action {
  margin-top: auto;
  padding-top: 0.75rem;
  align-self: flex-start;
}

/* A card is a column, so its button would otherwise stretch across the
   whole card rather than sit under the text. */
.grid.cards > .card > button,
.grid.cards > .card > a {
  align-self: flex-start;
}

/* The tag row follows the summary; only the action is pushed to the bottom,
   so the actions of a row line up regardless of how many tags a card has. */
.card-tags {
  padding-top: 0.15rem;
}

/* A summary is clamped so that one long paragraph does not stretch its card
   far past the cards beside it. */
.card-clamp {
  display: -webkit-box;
  -webkit-line-clamp: 4;
  line-clamp: 4;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.grid {
  display: grid;
  gap: 1rem;
}

.grid.cards {
  grid-template-columns: repeat(auto-fill, minmax(18rem, 1fr));
}

.grid.metrics {
  grid-template-columns: repeat(auto-fill, minmax(11rem, 1fr));
}

.metric {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.85rem 1rem;
}

.metric .value {
  font-size: 1.45rem;
  font-weight: 600;
  color: var(--accent);
  font-family: var(--mono);
}

.metric .label {
  color: var(--text-faint);
  font-size: 0.78rem;
  letter-spacing: 0.03em;
}

.page-header {
  margin-bottom: 1.5rem;
}

.page-header p {
  color: var(--text-muted);
  max-width: 60rem;
}

.breadcrumb {
  color: var(--text-faint);
  font-size: 0.82rem;
  margin-bottom: 0.4rem;
}

.breadcrumb a {
  color: var(--text-faint);
}

.tag {
  display: inline-block;
  white-space: nowrap;
  background: var(--surface-raised);
  border: 1px solid var(--border);
  color: var(--text-muted);
  border-radius: 999px;
  padding: 0.05rem 0.6rem;
  font-size: 0.75rem;
  margin: 0 0.3rem 0.3rem 0;
}

.badge {
  display: inline-block;
  white-space: nowrap;
  border-radius: var(--radius-small);
  padding: 0.05rem 0.4rem;
  font-size: 0.72rem;
  font-family: var(--mono);
  border: 1px solid var(--border-strong);
  color: var(--text-muted);
}

.notice {
  border-left: 3px solid var(--accent-strong);
  background: var(--accent-soft);
  padding: 0.6rem 0.9rem;
  border-radius: var(--radius-small);
  margin: 1rem 0;
  font-size: 0.88rem;
}

.notice.warning {
  border-color: var(--warning);
  background: rgba(232, 194, 106, 0.1);
}

.notice.error {
  border-color: var(--negative);
  background: rgba(242, 139, 130, 0.1);
}

.notice.muted {
  border-color: var(--border-strong);
  background: var(--surface);
  color: var(--text-muted);
}

.empty {
  color: var(--text-faint);
  font-style: italic;
  padding: 1rem 0;
}

/* Search results */

.result-list {
  list-style: none;
  padding: 0;
  margin: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.result {
  padding: 0.85rem 1.1rem;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}

.result:last-child {
  border-bottom: none;
}

.result:hover {
  background: var(--surface-raised);
}

.result-title {
  font-size: 1rem;
  font-weight: 600;
}

.result-summary {
  margin: 0.35rem 0 0.55rem;
  color: var(--text-muted);
  font-size: 0.88rem;
}

.result-meta {
  display: flex;
  gap: 0.35rem;
  flex-wrap: wrap;
}

/* Documentation */

.doc-body {
  min-width: 0;
}

.doc-body h1,
.doc-body h2,
.doc-body h3 {
  position: relative;
  scroll-margin-top: 4.5rem;
}

.doc-body .anchor {
  opacity: 0;
  margin-left: 0.4rem;
  color: var(--text-faint);
  font-weight: 400;
  text-decoration: none;
}

.doc-body h1:hover .anchor,
.doc-body h2:hover .anchor,
.doc-body h3:hover .anchor {
  opacity: 1;
}

.doc-body figure.code {
  margin: 1rem 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.doc-body figure.code figcaption {
  padding: 0.3rem 0.8rem;
  background: var(--surface-raised);
  border-bottom: 1px solid var(--border);
  color: var(--text-faint);
  font-size: 0.72rem;
  font-family: var(--mono);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.doc-body figure.code pre {
  padding: 0.9rem 1rem;
}

.doc-body a.concept-link {
  border-bottom: 1px dotted var(--accent-strong);
}

.doc-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) var(--toc-width);
  gap: 2.5rem;
  align-items: start;
}

/* A document with no headings gets the full width rather than an empty
   column at its right. */
.doc-layout.no-toc {
  grid-template-columns: minmax(0, 1fr);
  max-width: 46rem;
}

.doc-toc {
  position: sticky;
  top: 4.5rem;
  align-self: start;
  font-size: 0.85rem;
  max-height: calc(100vh - 6rem);
  overflow-y: auto;
  padding-left: 1rem;
  border-left: 1px solid var(--border);
}

/* Tables */

.table-wrap {
  overflow-x: auto;
  margin: 1rem 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
}

th,
td {
  text-align: left;
  padding: 0.5rem 0.8rem;
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}

/* A table cell that holds an identifier is kept on one line so that the
   column does not break a name across two lines. */
td:first-child {
  white-space: nowrap;
}

th {
  background: var(--surface-raised);
  color: var(--text-muted);
  font-weight: 600;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  white-space: nowrap;
}

th.numeric,
td.numeric {
  text-align: right;
  font-family: var(--mono);
  font-size: 0.82rem;
}

tbody tr:last-child td {
  border-bottom: none;
}

tbody tr:hover {
  background: rgba(127, 209, 255, 0.04);
}

/* Scalars */

.scalars {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(15rem, 1fr));
  gap: 0.6rem 1.5rem;
  margin: 1rem 0;
}

.scalar {
  display: flex;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.35rem 0;
  border-bottom: 1px dashed var(--border);
}

.scalar .label {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.scalar .value {
  font-family: var(--mono);
  font-size: 0.85rem;
  text-align: right;
  white-space: nowrap;
}

.scalar .unit {
  color: var(--text-faint);
  margin-left: 0.3rem;
}

/* Graph and charts */

.graph-canvas {
  width: 100%;
  /* The aspect of the layout space, so the drawing fills the canvas
     instead of being letterboxed inside it. */
  aspect-ratio: 2 / 1;
  min-height: 20rem;
  max-height: 46rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  display: block;
  cursor: grab;
  touch-action: none;
}

.graph-canvas:active {
  cursor: grabbing;
}

.graph-controls {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin: 0.75rem 0;
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 0.5rem;
  font-size: 0.78rem;
  color: var(--text-muted);
}

.legend span {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.legend i {
  width: 0.75rem;
  height: 0.75rem;
  border-radius: 50%;
  display: inline-block;
}

.chart {
  width: 100%;
  height: 14rem;
  display: block;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin: 0.75rem 0;
}

/* Signature and code blocks */

.signature {
  font-family: var(--mono);
  font-size: 0.82rem;
  background: var(--surface-raised);
  border: 1px solid var(--border);
  border-radius: var(--radius-small);
  padding: 0.5rem 0.7rem;
  overflow-x: auto;
  white-space: pre-wrap;
  word-break: break-word;
}

.signature .kw {
  color: #c792ea;
}

.signature .ty {
  color: #82aaff;
}

.signature .fn {
  color: #7fd1ff;
}

.api-item {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  padding: 0.85rem 1rem;
  margin-bottom: 0.6rem;
}

.api-item header {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  flex-wrap: wrap;
}

/* The items of one crate, two to a row, so that a crate with dozens of
   items stays a reasonable height. */
.item-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(28rem, 1fr));
  gap: 0.6rem;
  align-items: start;
}

.item-grid .api-item {
  margin-bottom: 0;
}

.api-item .name {
  font-family: var(--mono);
  font-size: 0.95rem;
  color: var(--accent);
  font-weight: 600;
}

.api-item .doc {
  color: var(--text-muted);
  font-size: 0.85rem;
  margin: 0.5rem 0 0;
  white-space: pre-wrap;
}

/* A doc comment rendered as Markdown. The block spacing is tightened
   because the comment is a fragment rather than a document. */
.api-doc {
  color: var(--text-muted);
  font-size: 0.85rem;
  margin-top: 0.5rem;
}

.api-doc p {
  margin: 0.4rem 0;
}

.api-doc ul,
.api-doc ol {
  margin: 0.4rem 0;
  padding-left: 1.2rem;
}

.api-doc h1,
.api-doc h2,
.api-doc h3,
.api-doc h4 {
  font-size: 0.9rem;
  margin: 0.75rem 0 0.3rem;
  color: var(--text);
}

.api-doc figure.code {
  margin: 0.5rem 0;
}

.api-doc figure.code figcaption {
  display: none;
}

.api-doc .table-wrap {
  margin: 0.5rem 0;
}

/* A crate summary on the crate page */

.crate-summary {
  color: var(--text-muted);
  font-size: 0.9rem;
  max-width: 60rem;
  margin-bottom: 0.5rem;
}

.crate-summary p {
  margin: 0.5rem 0;
}

/* A link to another interface item, rendered from a doc comment. */
.api-doc a.api-link,
.crate-summary a.api-link {
  color: var(--accent);
  border-bottom: 1px dotted var(--accent-strong);
}

/* The interface items a tool calls */

.calls {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.9rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--border);
}

.calls-label {
  color: var(--text-faint);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-right: 0.2rem;
}

/* The interface index */

.crate-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(20rem, 1fr));
  gap: 0.75rem;
  margin-top: 1rem;
}

.crate-card {
  display: block;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.85rem 1rem;
  color: var(--text);
}

.crate-card:hover {
  border-color: var(--accent-strong);
  background: var(--surface-raised);
  text-decoration: none;
}

.crate-card header {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.crate-card .name {
  font-family: var(--mono);
  font-size: 0.95rem;
  color: var(--accent);
  font-weight: 600;
}

.crate-card p {
  margin: 0.5rem 0 0;
  color: var(--text-muted);
  font-size: 0.85rem;
}

/* A tool in the tool index. The card is a link, so the whole area is the
   target and the hover is the affordance. */
.tool-card {
  color: var(--text);
}

.tool-card:hover {
  border-color: var(--accent-strong);
  background: var(--surface-raised);
  text-decoration: none;
}

.tool-card h4 {
  margin: 0 0 0.35rem;
  font-size: 0.98rem;
  color: var(--accent);
}

.tool-card p {
  margin: 0;
  color: var(--text-muted);
  font-size: 0.86rem;
}

.tool-card.selected {
  border-color: var(--accent);
  background: var(--accent-soft);
}

/* A row of links that wrap, used for the item filter results. */
.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.85rem;
}

.chip {
  display: inline-flex;
  align-items: baseline;
  gap: 0.4rem;
  background: var(--surface-raised);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.2rem 0.7rem;
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--accent);
}

.chip:hover {
  border-color: var(--accent-strong);
  text-decoration: none;
}

.chip-note {
  color: var(--text-faint);
  font-size: 0.72rem;
}

.kind {
  font-family: var(--mono);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.05rem 0.4rem;
  border-radius: var(--radius-small);
  background: var(--surface-raised);
  border: 1px solid var(--border-strong);
  color: var(--text-muted);
}

/* Tool forms */

.form-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(16rem, 1fr));
  gap: 0.9rem 1.25rem;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.field.wide {
  grid-column: 1 / -1;
}

.field label {
  font-size: 0.82rem;
  color: var(--text-muted);
  font-weight: 600;
}

.field .help {
  font-size: 0.75rem;
  color: var(--text-faint);
}

.field .unit {
  font-size: 0.72rem;
  color: var(--text-faint);
  font-family: var(--mono);
}

.field.invalid input,
.field.invalid textarea,
.field.invalid select {
  border-color: var(--negative);
}

.spinner {
  display: inline-block;
  width: 0.85rem;
  height: 0.85rem;
  border: 2px solid var(--border-strong);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  vertical-align: -0.1rem;
  margin-right: 0.4rem;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* Responsive */

@media (max-width: 700px) {
  /* The counters are a summary, not navigation, so they are the first
     thing to go when the bar is tight. */
  .topbar .badge {
    display: none;
  }

  .topbar {
    padding: 0.6rem 1rem;
  }
}

@media (max-width: 960px) {
  .app {
    flex-direction: column;
  }

  .sidebar {
    width: 100%;
    flex: none;
    height: auto;
    position: relative;
    max-height: 45vh;
  }

  .doc-layout {
    flex-direction: column;
  }

  .doc-toc {
    position: relative;
    top: 0;
    width: 100%;
    flex: none;
    max-height: none;
  }

  .content {
    padding: 1.25rem 1rem 3rem;
  }
}