/* ==========================================================================
   Base
   ========================================================================== */

:root {
  --color-bg: #ffffff;
  --color-bg-alt: #f5f6f8;
  --color-text: #1c1e21;
  --color-text-muted: #55595e;
  --color-border: #d9dce0;
  --color-primary: #1a4d8f;
  --color-primary-dark: #123a6b;
  --color-accent: #eef3fa;
  --max-width: 960px;
  --radius: 6px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.55;
}

a {
  color: var(--color-primary);
}

a:hover {
  color: var(--color-primary-dark);
}

h1, h2, h3 {
  line-height: 1.25;
}

img {
  max-width: 100%;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.25rem;
}

/* ==========================================================================
   Skip link (accessibility)
   ========================================================================== */

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--color-primary);
  color: #fff;
  padding: 0.6rem 1rem;
  z-index: 100;
}

.skip-link:focus {
  left: 0.5rem;
  top: 0.5rem;
}

/* ==========================================================================
   Header / Navigation
   ========================================================================== */

.site-header {
  border-bottom: 1px solid var(--color-border);
  background: var(--color-bg);
  position: sticky;
  top: 0;
  z-index: 10;
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  padding-top: 0.9rem;
  padding-bottom: 0.9rem;
  gap: 0.75rem;
}

.site-title {
  font-size: 1.15rem;
  font-weight: 700;
  text-decoration: none;
  color: var(--color-text);
}

.site-title:hover {
  color: var(--color-primary);
}

.main-nav ul {
  list-style: none;
  display: flex;
  gap: 1.25rem;
  margin: 0;
  padding: 0;
  flex-wrap: wrap;
}

.main-nav a {
  text-decoration: none;
  color: var(--color-text);
  font-weight: 500;
  padding: 0.25rem 0;
  border-bottom: 2px solid transparent;
}

.main-nav a:hover,
.main-nav a[aria-current="page"] {
  color: var(--color-primary);
  border-bottom-color: var(--color-primary);
}

/* ==========================================================================
   Hero
   ========================================================================== */

.hero {
  background: var(--color-accent);
  border-bottom: 1px solid var(--color-border);
}

.hero .container {
  padding-top: 1.5rem;
  padding-bottom: 1.5rem;
}

.hero h1 {
  margin-top: 0;
  font-size: 2rem;
}

.hero p {
  font-size: 1.05rem;
  color: var(--color-text-muted);
  max-width: 60ch;
}

/* ==========================================================================
   Buttons
   ========================================================================== */

.btn {
  display: inline-block;
  padding: 0.6rem 1.1rem;
  border-radius: var(--radius);
  text-decoration: none;
  font-weight: 600;
  border: 1px solid var(--color-primary);
}

.btn-primary {
  background: var(--color-primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--color-primary-dark);
  border-color: var(--color-primary-dark);
  color: #fff;
}

.btn-secondary {
  background: transparent;
  color: var(--color-primary);
}

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

.btn-row {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-top: 1.5rem;
}

/* ==========================================================================
   Main content sections
   ========================================================================== */

main {
  padding: 2.5rem 0 3rem;
}

main code {
  background: var(--color-accent);
  color: var(--color-primary);
  padding: 0.15rem 0.6rem;
  border-radius: 999px;
  font-size: 0.85em;
  font-family: inherit;
}

.lang-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin: 1rem 0 2rem;
}

.lang-pill {
  display: inline-block;
  background: var(--color-accent);
  color: var(--color-primary);
  padding: 0.35rem 0.9rem;
  border-radius: 999px;
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
  transition: opacity 0.15s ease;
}

.lang-pill:hover,
.lang-pill:focus {
  opacity: 0.75;
}

.section {
  margin-bottom: 2.5rem;
}

main table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.95rem;
  display: block;
  overflow-x: auto;
}

main th,
main td {
  border: 1px solid var(--color-border);
  padding: 0.6rem 0.9rem;
  text-align: left;
  word-wrap: break-word;
}

main th {
  background: var(--color-accent);
  color: var(--color-primary);
  font-weight: 600;
}

main tbody tr:nth-child(even) {
  background: var(--color-bg-alt);
}

/* Scoped to tables that should have evenly-sized columns regardless of
   content length (e.g. the Business Case comparison table). Most tables
   (long technical tables with varied column widths) should NOT use this —
   they read better sized to their content. */
.table-fixed table {
  table-layout: fixed;
}

/* ==========================================================================
   Whitepaper pages
   ========================================================================== */

.whitepaper h2 {
  margin-top: 2.75rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--color-accent);
}

.whitepaper h3 {
  margin-top: 2rem;
  color: var(--color-primary);
}

.whitepaper p,
.whitepaper > ul,
.whitepaper > ol {
  max-width: 72ch;
  line-height: 1.7;
}

.whitepaper li {
  margin-bottom: 0.4rem;
}

.whitepaper blockquote {
  margin: 1.5rem 0;
  padding: 0.85rem 1.25rem;
  max-width: 72ch;
  border-left: 3px solid var(--color-primary);
  background: var(--color-bg-alt);
  border-radius: 0 var(--radius) var(--radius) 0;
}

.whitepaper blockquote p {
  margin: 0.4rem 0;
  color: var(--color-text-muted);
  font-size: 0.95rem;
  max-width: none;
}

.whitepaper code {
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  padding: 0.1rem 0.4rem;
  font-size: 0.88em;
  color: var(--color-text);
}

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

/* Full abstract/keywords callout (Conformance Evidence, UBD) */
.whitepaper-abstract {
  max-width: 72ch;
  margin: 1.5rem 0 2rem;
  padding: 1.25rem 1.5rem;
  background: var(--color-accent);
  border-left: 4px solid var(--color-primary);
  border-radius: 0 var(--radius) var(--radius) 0;
}

.whitepaper-abstract p {
  max-width: none;
  margin: 0.6rem 0;
  color: var(--color-text);
}

.whitepaper-abstract p:first-child {
  margin-top: 0;
}

.whitepaper-abstract p:last-child {
  margin-bottom: 0;
}

/* Short one-line italic notes (e.g. "First draft", "Created 2026-06-25...") */
.whitepaper-meta {
  max-width: 72ch;
  margin: 0.5rem 0 2rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-size: 0.9rem;
  font-style: italic;
}

/* Highlights the last column (Miguel's Version in the Business Case table)
   with a bold outline around the whole column (not between each row), so it
   stands out from the other columns being compared. Background is left
   alone so it follows the same white/grey row striping as every other
   column instead of a distinct tint. */
.table-fixed th:last-child,
.table-fixed td:last-child {
  border-left: 2px solid var(--color-primary);
  border-right: 2px solid var(--color-primary);
}

.table-fixed thead th:last-child {
  border-top: 2px solid var(--color-primary);
}

.table-fixed tbody tr:last-child td:last-child {
  border-bottom: 2px solid var(--color-primary);
}

.screenshot-gallery {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: center;
  gap: 1rem;
  margin: 1.5rem 0;
}

.screenshot-gallery img {
  height: 260px;
  width: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
}

@media (max-width: 700px) {
  .screenshot-gallery {
    flex-direction: column;
    align-items: center;
  }

  .screenshot-gallery img {
    height: auto;
    width: 100%;
    max-width: 400px;
  }
}

.note {
  font-weight: 700;
}

.note a {
  font-weight: 400;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1rem;
  margin-top: 1.25rem;
}

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

.card h3 {
  margin-top: 0;
}

.repo-list {
  list-style: none;
  padding: 0;
  margin: 1.25rem 0 0;
  display: grid;
  gap: 0.75rem;
}

.repo-list li {
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 0.85rem 1rem;
}

.repo-list a {
  font-weight: 600;
  text-decoration: none;
}

.repo-list a:hover {
  text-decoration: underline;
}

.repo-list p {
  margin: 0.3rem 0 0;
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

/* ==========================================================================
   Publications page section distinction
   ========================================================================== */

.pub-jumpnav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin: 0 0 2rem;
}

.pub-jumpnav a {
  display: inline-block;
  background: var(--color-accent);
  color: var(--color-primary);
  padding: 0.35rem 0.9rem;
  border-radius: 999px;
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
}

.pub-jumpnav a:hover {
  opacity: 0.8;
}

.pub-section {
  padding: 1.75rem 1.75rem 2rem;
  border-radius: var(--radius);
  border: 1px solid var(--color-border);
  margin-top: 2.25rem;
}

.pub-section:first-of-type {
  margin-top: 0;
}

.pub-section--whitepapers {
  background: var(--color-bg);
}

.pub-section--reviews {
  background: var(--color-bg-alt);
}

.heading-row {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-bottom: 0.75rem;
}

.heading-row h2 {
  margin: 0;
}

.heading-subtitle {
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

.pub-eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--color-text-muted);
}

.pub-intro {
  color: var(--color-text-muted);
}

/* ==========================================================================
   Q&A table of contents
   ========================================================================== */

.qa-index {
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-bg-alt);
  padding: 1.5rem;
  margin-bottom: 2rem;
}

.qa-index h2 {
  margin-top: 0;
  margin-bottom: 1.25rem;
  font-size: 1.15rem;
}

.qa-index-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 1.5rem;
}

.qa-index-group h3 {
  margin: 0 0 0.5rem;
  font-size: 0.95rem;
  color: var(--color-primary);
}

.qa-index-group ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.qa-index-group li {
  margin-bottom: 0.4rem;
}

.qa-index-group a {
  font-size: 0.9rem;
  text-decoration: none;
  color: var(--color-text);
}

.qa-index-group a:hover {
  color: var(--color-primary);
  text-decoration: underline;
}

/* ==========================================================================
   Knowledge base / FAQ
   ========================================================================== */

.kb-controls {
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
  margin-bottom: 1.75rem;
}

.kb-search-field {
  position: relative;
}

#kb-search-input {
  width: 100%;
  padding: 0.65rem 0.9rem;
  font-size: 1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
}

#kb-search-input:focus {
  outline: 2px solid var(--color-primary);
  outline-offset: 1px;
}

.kb-categories {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.kb-category-btn {
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  color: var(--color-text);
  padding: 0.4rem 0.85rem;
  border-radius: 999px;
  font-size: 0.9rem;
  cursor: pointer;
}

.kb-category-btn:hover {
  border-color: var(--color-primary);
}

.kb-category-btn[aria-pressed="true"] {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: #fff;
}

.kb-meta {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  margin-bottom: 1rem;
}

.kb-results {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.kb-entry {
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-bg);
}

.kb-entry summary {
  cursor: pointer;
  padding: 0.9rem 1.1rem;
  font-weight: 600;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
}

.kb-entry summary::-webkit-details-marker {
  display: none;
}

.kb-entry summary::after {
  content: "+";
  font-weight: 400;
  color: var(--color-text-muted);
  flex-shrink: 0;
}

.kb-entry[open] summary::after {
  content: "\2212";
}

.kb-entry-body {
  padding: 0 1.1rem 1.1rem;
  color: var(--color-text-muted);
}

.kb-tag {
  display: inline-block;
  background: var(--color-accent);
  color: var(--color-primary);
  border-radius: 999px;
  padding: 0.15rem 0.6rem;
  font-size: 0.78rem;
  margin: 0.6rem 0.4rem 0 0;
}

.kb-category-label {
  display: block;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--color-text-muted);
  font-weight: 600;
  margin-bottom: 0.15rem;
}

.kb-no-results {
  color: var(--color-text-muted);
  padding: 1.5rem 0;
}

mark {
  background: #fff2ac;
  color: inherit;
  padding: 0 0.1em;
}

/* ==========================================================================
   Footer
   ========================================================================== */

.site-footer {
  border-top: 1px solid var(--color-border);
  background: var(--color-bg-alt);
}

.site-footer .container {
  padding-top: 1.5rem;
  padding-bottom: 1.5rem;
  color: var(--color-text-muted);
  font-size: 0.9rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.5rem;
  justify-content: space-between;
}

.site-footer a {
  color: var(--color-text-muted);
}

.site-footer a:hover {
  color: var(--color-primary);
}

/* ==========================================================================
   Utility
   ========================================================================== */

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

@media (max-width: 600px) {
  .hero h1 {
    font-size: 1.6rem;
  }
}