/*
 * FES visual identity for sphinx-book-theme (pydata-sphinx-theme).
 *
 * The palette is defined once as --fes-* tokens, then mapped onto the
 * theme's --pst-color-* variables. Only a few targeted rules follow; the
 * layout of the theme is left untouched. MathJax output is not restyled.
 *
 * Contrast (WCAG 2.x), text or link colour on background:
 *
 *   Light                       on #FFFFFF   on Estran #EEF4F6
 *   Text        #1A2433         15.62        14.07
 *   Muted       #4A5869          7.26         6.54
 *   Abyss       #0B2545         15.39        13.85
 *   Tide (link) #0C747E          5.50         4.96
 *   Tide hover  #0B5F67          7.38         6.64
 *
 *   Dark                        on #0A1626   on Estran #132235
 *   Text        #E6EDF3         15.38        13.59
 *   Muted       #A9B8C7          8.97         7.93
 *   Abyss       #9FC3E7          9.89         8.74
 *   Tide (link) #4FD1C5          9.74         8.61
 *   Tide hover  #8BE3DA         12.20        10.78
 *
 * Spring tide #F2A541 is for charts and illustrations only, never text
 * (2.05:1 on white).
 */

html[data-theme="light"] {
  --fes-background: #ffffff;
  --fes-text: #1a2433;
  --fes-muted: #4a5869;
  --fes-abyss: #0b2545;
  --fes-tide: #0c747e;
  --fes-tide-hover: #0b5f67;
  --fes-estran: #eef4f6;
  --fes-border: #d5dee6;
  --fes-spring-tide: #f2a541;
}

html[data-theme="dark"] {
  --fes-background: #0a1626;
  --fes-text: #e6edf3;
  --fes-muted: #a9b8c7;
  --fes-abyss: #9fc3e7;
  --fes-tide: #4fd1c5;
  --fes-tide-hover: #8be3da;
  --fes-estran: #132235;
  --fes-border: #23364d;
  --fes-spring-tide: #f2a541;
}

html[data-theme="light"],
html[data-theme="dark"] {
  --pst-color-background: var(--fes-background);
  --pst-color-on-background: var(--fes-background);
  --pst-color-surface: var(--fes-estran);
  --pst-color-on-surface: var(--fes-estran);
  --pst-color-text-base: var(--fes-text);
  --pst-color-text-muted: var(--fes-muted);
  --pst-color-heading: var(--fes-abyss);
  --pst-color-border: var(--fes-border);
  --pst-color-primary: var(--fes-tide);
  --pst-color-secondary: var(--fes-abyss);
  --pst-color-accent: var(--fes-tide);
  --pst-color-link: var(--fes-tide);
  --pst-color-link-hover: var(--fes-tide-hover);
  --pst-color-inline-code: var(--fes-tide-hover);
  --pst-color-inline-code-links: var(--fes-tide);
  --pst-color-target: var(--fes-estran);
  --pst-color-table-row-hover-bg: var(--fes-estran);

  /* System fonts only: nothing is downloaded. */
  --pst-font-family-base: system-ui, -apple-system, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, sans-serif;
  --pst-font-family-heading: var(--pst-font-family-base);
  --pst-font-family-monospace: ui-monospace, "SF Mono", Menlo, Consolas,
    "Liberation Mono", monospace;
}

/* Headings ---------------------------------------------------------------- */

.bd-content h1,
.bd-content h2,
.bd-content h3,
.bd-content h4 {
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--fes-abyss);
}

/* Sidebar logo: the horizontal lockup would otherwise fill the sidebar. */

.bd-sidebar-primary .navbar-brand img.logo__image {
  height: 3rem;
  width: auto;
}

/* Home page banner (index.rst) -------------------------------------------- */

/* The page title stays in the document for search and screen readers; the
   banner shows the logo in its place. */
section:has(> .fes-hero) > h1 {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
}

.fes-hero {
  margin: 0.5rem 0 2rem;
  padding: 1.5rem 0 1.75rem;
  border-bottom: 1px solid var(--fes-border);
}

.fes-hero img.fes-hero-logo {
  display: block;
  height: 72px;
  width: auto;
  max-width: 100%;
  margin: 0 0 1rem;
}

.fes-hero p {
  margin: 0;
  max-width: 40rem;
  font-size: 1.2rem;
  line-height: 1.5;
  color: var(--fes-muted);
}

/* Admonitions: flatter boxes on the Estran surface. Semantic colours of
   warnings and errors are kept. */

.bd-content .admonition {
  border-radius: 4px;
  box-shadow: none;
  background-color: var(--fes-estran);
}

.bd-content .admonition.note,
.bd-content .admonition.seealso,
.bd-content .admonition.hint {
  border-color: var(--fes-tide);
}

.bd-content .admonition.note > .admonition-title,
.bd-content .admonition.seealso > .admonition-title,
.bd-content .admonition.hint > .admonition-title {
  background-color: var(--fes-estran);
}

.bd-content .admonition.note > .admonition-title::after,
.bd-content .admonition.seealso > .admonition-title::after,
.bd-content .admonition.hint > .admonition-title::after {
  color: var(--fes-tide);
}

/* Tables (constituent lists): aligned figures, Estran header. */

.bd-content table.docutils {
  font-variant-numeric: tabular-nums;
}

.bd-content table.docutils th {
  background-color: var(--fes-estran);
  color: var(--fes-abyss);
}

/* Gallery cards (sphinx-gallery). */

.sphx-glr-thumbcontainer {
  border-color: var(--fes-border) !important;
  border-radius: 6px;
  box-shadow: none !important;
}

.sphx-glr-thumbcontainer:hover {
  border-color: var(--fes-tide) !important;
}

.sphx-glr-thumbcontainer a.internal,
.sphx-glr-thumbcontainer .sphx-glr-thumbnail-title {
  color: var(--fes-abyss);
}

/* Partner logos in the footer (see _static/partners/README.md). */

.fes-partners {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  align-items: center;
  margin-top: 0.75rem;
}

.fes-partners img {
  height: 40px;
  width: auto;
}