/* ZDDC — Zero Day Document Control */
/* Professional, trustworthy, reliable — but friendly and inviting */

/* ── Design tokens ── */
:root {
  /* Typography */
  --font-sans:    'Inter', system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, sans-serif;
  --font-mono:    'SF Mono', 'Fira Code', 'Consolas', monospace;
  
  /* Color palette - Steel blue accent (#2a5a8a) */
  --color-accent:     #2a5a8a;
  --color-accent-hover: #1d4060;
  --color-accent-soft: #e8f0f7;
  --color-accent-dark: #3d7ab5;
  
  --color-bg:         #ffffff;
  --color-bg-subtle:  #f8f9fa;
  --color-bg-muted:   #e9ecef;
  
  --color-text:       #1f2937;
  --color-text-muted: #6b7280;
  --color-text-light: #9ca3af;
  
  --color-border:     #e5e7eb;
  
  /* Semantic colors */
  --color-Tracking:   #dbeafe;    /* blue-tint */
  --color-Revision:   #bbf7d0;    /* green-tint */
  --color-Status:     #fde68a;    /* amber-tint */
  --color-Title:      #f3f4f6;    /* gray-tint */
  
  /* Spacing */
  --spacing-xs:   0.25rem;
  --spacing-sm:   0.5rem;
  --spacing-md:   1rem;
  --spacing-lg:   1.5rem;
  --spacing-xl:   2rem;
  --spacing-2xl:  3rem;
  
  /* Sizing */
  --radius-sm:    6px;
  --radius-md:    8px;
  --radius-lg:    12px;
  --radius-xl:    16px;
  
  /* Shadows */
  --shadow-sm:    0 1px 2px rgba(0,0,0,0.05);
  --shadow-md:    0 2px 4px rgba(0,0,0,0.05);
  --shadow-lg:    0 4px 8px rgba(0,0,0,0.08);
  --shadow-xl:    0 10px 15px -3px rgba(0,0,0,0.1);
  
  /* Max width & typography */
  --max-width: 900px;
  --font-size-base: 16px;
  --line-height:  1.6;
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { 
  font-size: var(--font-size-base);
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: var(--line-height);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ── Layout ── */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}


/* ── Header ── */
.site-header {
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  padding: var(--spacing-sm) 0;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}

.header-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--spacing-md);
}

.brand {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  text-decoration: none;
  color: var(--color-text);
  font-weight: 600;
  font-size: 1.1rem;
}

.brand-logo {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
  display: block;
}

/* ── Header Navigation ── */
.header-nav {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.nav-link {
  color: var(--color-text);
  text-decoration: none;
  font-size: 0.9rem;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  transition: background 0.2s, color 0.2s;
}

.nav-link:hover {
  background: var(--color-bg-subtle);
  color: var(--color-accent);
}

.nav-link.active {
  color: var(--color-accent);
  font-weight: 600;
}

.dropdown {
  position: relative;
}

.dropdown-toggle {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  color: var(--color-text);
  text-decoration: none;
  font-size: 0.9rem;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  cursor: pointer;
  background: transparent;
  border: none;
  transition: background 0.2s;
}

.dropdown-toggle:hover {
  background: var(--color-bg-subtle);
}

.dropdown-menu {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  /* transparent top padding bridges the gap between button and menu */
  padding-top: 6px;
  z-index: 1000;
}

.dropdown-menu__inner {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  min-width: 200px;
  padding: var(--spacing-xs);
}

/* Show on JS class OR on CSS hover of the whole .dropdown wrapper */
.dropdown-menu.show,
.dropdown:hover .dropdown-menu {
  display: block;
}

.dropdown-menu a {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-xs) var(--spacing-sm);
  color: var(--color-text);
  text-decoration: none;
  white-space: nowrap;
  font-size: 0.9rem;
  border-radius: var(--radius-sm);
  transition: background 0.2s;
}

.dropdown-menu a:hover {
  background: var(--color-bg-subtle);
  color: var(--color-accent);
}

.dropdown-menu-icon {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
  opacity: 0.6;
  fill: currentColor;
}

/* ── Main Content ── */
main {
  flex: 1;
}

/* ── Hero Section ── */
.hero {
  padding: var(--spacing-2xl) 0 var(--spacing-xl);
  text-align: center;
  /* Subtle radial gradient background */
  background: radial-gradient(circle at center, rgba(42, 90, 138, 0.03) 0%, transparent 60%);
}

.hero h1 {
  font-size: clamp(2.5rem, 7vw, 3.75rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: var(--spacing-md);
  color: var(--color-text);
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--color-text-muted);
  max-width: 600px;
  margin: 0 auto var(--spacing-xl);
  line-height: 1.6;
  font-weight: 400;
}

/* ── Pain Point Sections ── */
.pain-section {
  padding: var(--spacing-2xl) 0;
  background: #fff8f8;
  border-top: 1px solid #fce8e8;
  border-bottom: 1px solid #fce8e8;
  margin-bottom: -1px; /* collapse adjacent borders */
}

.pain-section__badge {
  display: inline-block;
  background: #fef2f2;
  color: #991b1b;
  border: 1px solid #fecaca;
  font-size: 0.75rem;
  font-weight: 700;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: 50px;
  margin-bottom: var(--spacing-md);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.pain-section__heading {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: var(--spacing-md);
  color: var(--color-text);
}

.pain-section__body {
  color: var(--color-text-muted);
  line-height: 1.65;
  max-width: 700px;
}

/* ── Solution sections ── */
.solution-section {
  padding: var(--spacing-2xl) 0;
  background: #f4fbf6;
  border-top: 1px solid #d1ead9;
  border-bottom: 1px solid #d1ead9;
  margin-bottom: -1px;
}

.solution-section__badge {
  display: inline-block;
  background: #f0faf4;
  color: #166534;
  border: 1px solid #bbf7d0;
  font-size: 0.75rem;
  font-weight: 700;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: 50px;
  margin-bottom: var(--spacing-md);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.solution-section__heading {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: var(--spacing-md);
  color: var(--color-text);
}

.solution-section__body {
  color: var(--color-text-muted);
  line-height: 1.65;
  max-width: 700px;
}

/* ── Zone dividers (between problem and solution bands) ── */
.zone-break {
  padding: var(--spacing-2xl) 0;
  background: var(--color-bg);
  text-align: center;
}

.zone-break__heading {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--color-text);
  margin-bottom: var(--spacing-sm);
}

.zone-break__sub {
  color: var(--color-text-muted);
  max-width: 560px;
  margin: 0 auto;
  font-size: 1.05rem;
  line-height: 1.6;
}

/* ── Filename Anatomy ── */
.filename-anatomy {
  font-family: var(--font-mono);
  font-size: 0.95rem;
  background: var(--color-bg-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--spacing-lg);
  overflow-x: auto;
  white-space: nowrap;
}

.filename-anatomy__part {
  padding: 2px 4px;
  border-radius: 4px;
}

.filename-anatomy__part--tracking {
  background: var(--color-Tracking);
  color: #1e40af;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]):not([data-theme="dark"]) .filename-anatomy__part--tracking {
    color: #93c5fd;
  }
}
html[data-theme="dark"] .filename-anatomy__part--tracking {
  color: #93c5fd;
}

.filename-anatomy__part--revision {
  background: var(--color-Revision);
  color: #166534;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]):not([data-theme="dark"]) .filename-anatomy__part--revision {
    color: #86efac;
  }
}
html[data-theme="dark"] .filename-anatomy__part--revision {
  color: #86efac;
}

.filename-anatomy__part--status {
  background: var(--color-Status);
  color: #92400e;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]):not([data-theme="dark"]) .filename-anatomy__part--status {
    color: #fcd34d;
  }
}
html[data-theme="dark"] .filename-anatomy__part--status {
  color: #fcd34d;
}

.filename-anatomy__part--title {
  background: var(--color-Title);
  color: var(--color-text);
}

.filename-parts {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-sm);
  margin-top: var(--spacing-md);
}

.filename-parts__dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  display: inline-block;
  margin-right: var(--spacing-xs);
}

.filename-parts__dot--tracking { background: #1e40af; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]):not([data-theme="dark"]) .filename-parts__dot--tracking {
    background: #93c5fd;
  }
}
html[data-theme="dark"] .filename-parts__dot--tracking {
  background: #93c5fd;
}

.filename-parts__dot--revision { background: #166534; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]):not([data-theme="dark"]) .filename-parts__dot--revision {
    background: #86efac;
  }
}
html[data-theme="dark"] .filename-parts__dot--revision {
  background: #86efac;
}

.filename-parts__dot--status { background: #92400e; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]):not([data-theme="dark"]) .filename-parts__dot--status {
    background: #fcd34d;
  }
}
html[data-theme="dark"] .filename-parts__dot--status {
  background: #fcd34d;
}

.filename-parts__dot--title { background: var(--color-text-muted); }

.filename-parts__label {
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

/* ── Status Badge ── */
.status-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  background: var(--color-accent-soft);
  color: var(--color-accent);
  padding: 2px 6px;
  border-radius: 4px;
  font-weight: 600;
}

/* ── Tool Cards ── */
.tool-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 10px;
  padding: 24px;
  transition: transform 0.2s, box-shadow 0.2s;
}

.tool-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
}

.tool-card__title {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: var(--spacing-sm);
  color: var(--color-text);
}

.tool-card__desc {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: var(--spacing-lg);
}

.tool-card__link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--color-accent);
  color: white;
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--radius-md);
  font-weight: 600;
  text-decoration: none;
  font-size: 0.9rem;
  transition: background 0.2s;
}

.tool-card__link:hover {
  background: var(--color-accent-hover);
}

/* Three tool cards: all three side by side on wide screens, all three
   stacked on narrow screens — never a 2-then-1 wrap. */
.tools-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-lg);
  margin-top: var(--spacing-lg);
  align-items: start;
}
@media (min-width: 860px) {
  .tools-grid { grid-template-columns: repeat(3, 1fr); }
}

/* ── Steps List ── */
.steps {
  margin: var(--spacing-xl) 0;
  padding-left: 0;
}

.step {
  display: flex;
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
}

.step:last-child {
  margin-bottom: 0;
}

.step__number {
  flex-shrink: 0;
  width: 36px;
  height: 36px;
  background: var(--color-accent);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1rem;
  flex-shrink: 0;
}

.step__content {
  flex: 1;
}

.step__content h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: var(--spacing-xs);
  color: var(--color-text);
}

.step__content p {
  margin: 0;
  color: var(--color-text-muted);
  line-height: 1.55;
}

/* ── Highlight Box ── */
.highlight-box {
  background: var(--color-bg-subtle);
  border-left: 3px solid var(--color-accent);
  padding: var(--spacing-lg);
  margin: var(--spacing-lg) 0;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

.highlight-box p {
  margin-bottom: 0;
  line-height: 1.65;
  color: var(--color-text);
}

/* ── Reference Layout ── */
.ref-layout {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: var(--spacing-2xl);
  margin-top: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
  max-width: 1100px;
}

.ref-toc {
  position: sticky;
  top: 80px;
  height: fit-content;
}

.ref-toc__item {
  margin-bottom: var(--spacing-xs);
}

.ref-toc__link {
  display: block;
  padding: var(--spacing-xs) var(--spacing-sm);
  color: var(--color-text-muted);
  text-decoration: none;
  font-size: 0.9rem;
  border-radius: var(--radius-sm);
  transition: all 0.2s;
}

.ref-toc__link:hover {
  color: var(--color-accent);
  background: var(--color-bg-subtle);
}

.ref-toc__link--active {
  color: var(--color-accent);
  background: var(--color-accent-soft);
  font-weight: 600;
}

.ref-content {
  min-width: 0;
  padding-top: var(--spacing-sm);
}

.ref-content h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-top: var(--spacing-2xl);
  margin-bottom: var(--spacing-lg);
  color: var(--color-text);
}

.ref-content p {
  color: var(--color-text-muted);
  line-height: 1.65;
  margin-bottom: var(--spacing-md);
}

.ref-content code {
  font-family: var(--font-mono);
  color: var(--color-accent);
  background: var(--color-bg-subtle);
  padding: 2px 6px;
  border-radius: 3px;
  font-size: 0.9em;
}

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

.ref-content a:hover {
  text-decoration: underline;
}

/* ── Tables ── */
table {
  width: 100%;
  border-collapse: collapse;
  margin-top: var(--spacing-lg);
  font-size: 0.875rem;
}

th, td {
  padding: 0.375rem var(--spacing-sm);
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}

th {
  background: var(--color-bg-subtle);
  font-weight: 600;
  color: var(--color-text);
}

tr:nth-child(even) {
  background: var(--color-bg-subtle);
}

tr:nth-child(even) td {
  background: var(--color-bg-subtle);
}

/* ── Section Divider ── */
.section-divider {
  height: 1px;
  background: linear-gradient(to right, transparent, var(--color-border), transparent);
  margin: var(--spacing-2xl) 0;
  border: none;
}

/* ── Grid Utilities ── */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--spacing-lg);
  margin: var(--spacing-xl) 0;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-lg);
  margin: var(--spacing-xl) 0;
}

/* ── Responsive grids ── */
@media (max-width: 900px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .filename-parts { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
  /* Container */
  .container { padding: 0 var(--spacing-md); }

  /* Header: brand left, nav below, theme toggle at end */
  .header-content { flex-wrap: wrap; gap: var(--spacing-xs); }
  .brand { flex: 1; }
  .header-nav { width: 100%; justify-content: flex-start; }

  /* Hero */
  .hero { padding: var(--spacing-xl) 0 var(--spacing-lg); }
  .hero-cta-group { flex-direction: column; align-items: center; }

  /* Grids */
  .grid-2, .grid-4 { grid-template-columns: 1fr; }
  .filename-parts { grid-template-columns: repeat(2, 1fr); }

  /* Reference page: sidebar becomes plain list above content */
  .ref-layout { grid-template-columns: 1fr; gap: var(--spacing-lg); }
  .ref-toc { position: static; }

  /* Misc */
  .filename-anatomy { font-size: 0.85rem; }
}

/* ── Content Block ── */
.content-block {
  margin-bottom: var(--spacing-xl);
}

.content-block h2 {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-lg);
  font-weight: 700;
  color: var(--color-text);
}

.content-block h3 {
  font-size: 1.25rem;
  margin-top: var(--spacing-xl);
  margin-bottom: var(--spacing-md);
  font-weight: 600;
  color: var(--color-text);
}

.content-block p {
  margin-bottom: var(--spacing-md);
  line-height: 1.65;
  color: var(--color-text-muted);
}

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

.content-block a:hover {
  text-decoration: underline;
}

/* ── Feature Cards ── */
.feature-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
  transition: border-color 0.2s;
}

.feature-card:hover {
  border-color: var(--color-accent);
}

.feature-title {
  font-weight: 600;
  font-size: 1.1rem;
  margin-bottom: var(--spacing-sm);
  color: var(--color-text);
}

.feature-desc {
  color: var(--color-text-muted);
  font-size: 1rem;
  line-height: 1.6;
}

/* ── Code Blocks ── */
.code-block {
  background: var(--color-bg-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--spacing-lg);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  overflow-x: auto;
  white-space: pre;
  margin: var(--spacing-md) 0;
}

.code-block code {
  color: var(--color-text);
  font-family: var(--font-mono);
}

/* ── Filename Example ── */
.filename-example {
  background: var(--color-bg-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--spacing-lg);
  font-family: var(--font-mono);
  font-size: 0.95rem;
  white-space: pre-wrap;
  word-break: break-all;
  margin-top: var(--spacing-lg);
}

.filename-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-sm);
  margin-top: var(--spacing-md);
}

.filename-item {
  text-align: center;
  padding: var(--spacing-sm);
  border-radius: var(--radius-sm);
  background: var(--color-bg);
}

.filename-item .name {
  font-weight: 600;
  font-size: 0.85rem;
  margin-bottom: var(--spacing-xs);
  color: var(--color-text);
}

.filename-item .desc {
  font-size: 0.75rem;
  color: var(--color-text-muted);
  line-height: 1.4;
}

/* ── Process Flow ── */
.process-flow {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
  margin: var(--spacing-xl) 0;
}

.process-step {
  display: flex;
  align-items: flex-start;
  gap: var(--spacing-lg);
}

.process-icon {
  width: 40px;
  height: 40px;
  background: var(--color-accent-soft);
  color: var(--color-accent);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.process-icon svg {
  width: 20px;
  height: 20px;
}

.process-content {
  flex: 1;
}

.process-content h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: var(--spacing-xs);
  color: var(--color-text);
}

.process-content p {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

/* ── Footer ── */
.site-footer {
  background: var(--color-bg);
  border-top: 1px solid var(--color-border);
  padding: var(--spacing-xl) 0;
  margin-top: var(--spacing-2xl);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--spacing-md);
}

.footer-links {
  display: flex;
  gap: var(--spacing-md);
}

.footer-links a {
  color: var(--color-text-muted);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color 0.2s;
}

.footer-links a:hover {
  color: var(--color-accent);
}

/* ── Utility classes ── */
.muted { color: var(--color-text-muted); }
.text-center { text-align: center; }
.text-left { text-align: left; }
.my-md { margin: var(--spacing-md) 0; }
.my-lg { margin: var(--spacing-lg) 0; }
.text-xs { font-size: 0.75rem; }
.text-sm { font-size: 0.875rem; }
.text-lg { font-size: 1.125rem; }
.text-xl { font-size: 1.25rem; }
.font-mono { font-family: var(--font-mono); }

/* ── Brand color utilities ── */
.accent-text { color: var(--color-accent); }
.accent-bg { background: var(--color-accent-soft); }

/* ── Hero CTA ── */
.hero-cta-group {
  display: flex;
  gap: var(--spacing-sm);
  justify-content: center;
  flex-wrap: wrap;
}

.hero-cta {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  background: var(--color-accent);
  color: white;
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 1rem;
  text-decoration: none;
  transition: background 0.2s;
}

.hero-cta:hover {
  background: var(--color-accent-hover);
}

/* ── Theme Toggle Button ── */
.theme-toggle {
  background: transparent;
  border: none;
  cursor: pointer;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  transition: background 0.2s, color 0.2s;
}

.theme-toggle:hover {
  background: var(--color-bg-subtle);
  color: var(--color-text);
}

.theme-toggle svg {
  width: 16px;
  height: 16px;
  fill: currentColor;
}

/* ── Dark Mode (System Preference) ── */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]):not([data-theme="dark"]) {
    --color-bg: #0d1117;
    --color-bg-subtle: #161b22;
    --color-bg-muted: #21262d;
    --color-text: #e6edf3;
    --color-text-muted: #8b949e;
    --color-text-light: #6e7681;
    --color-border: #30363d;

    --color-accent: #58a6ff;
    --color-accent-hover: #3d84c2;
    --color-accent-soft: #1f4d7a;
    --color-accent-dark: #79c0ff;

    --color-Tracking: #264e7d;
    --color-Revision: #134a29;
    --color-Status: #5c4a00;
    --color-Title: #3a4659;
  }
}

/* ── Dark Theme (Explicit) ── */
html[data-theme="dark"] {
  --color-bg: #0d1117;
  --color-bg-subtle: #161b22;
  --color-bg-muted: #21262d;
  --color-text: #e6edf3;
  --color-text-muted: #8b949e;
  --color-text-light: #6e7681;
  --color-border: #30363d;

  --color-accent: #58a6ff;
  --color-accent-hover: #3d84c2;
  --color-accent-soft: #1f4d7a;
  --color-accent-dark: #79c0ff;

  --color-Tracking: #264e7d;
  --color-Revision: #134a29;
  --color-Status: #5c4a00;
  --color-Title: #3a4659;
}

/* Brand logo's navy bg-rect blends into the dark page bg; lift it. */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]):not([data-theme="dark"]) .brand-logo > rect {
    fill: #2a5a8a;
  }
}
html[data-theme="dark"] .brand-logo > rect {
  fill: #2a5a8a;
}

/* ── Pain badge dark mode ── */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]):not([data-theme="dark"]) .pain-section__badge {
    background: #450a0a;
    color: #fca5a5;
    border-color: #7f1d1d;
  }
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]):not([data-theme="dark"]) .pain-section {
    background: #1c0f0f;
    border-color: #3d1515;
  }
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]):not([data-theme="dark"]) .solution-section {
    background: #0d1f14;
    border-color: #1a3d25;
  }
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]):not([data-theme="dark"]) .solution-section__badge {
    background: #0d1f14;
    color: #86efac;
    border-color: #166534;
  }
}

html[data-theme="dark"] .pain-section {
  background: #1c0f0f;
  border-color: #3d1515;
}

html[data-theme="dark"] .solution-section {
  background: #0d1f14;
  border-color: #1a3d25;
}

html[data-theme="dark"] .solution-section__badge {
  background: #0d1f14;
  color: #86efac;
  border-color: #166534;
}

html[data-theme="dark"] .pain-section__badge {
  background: #450a0a;
  color: #fca5a5;
  border-color: #7f1d1d;
}

/* ── Light Theme (Explicit) ── */
html[data-theme="light"] {
  --color-bg: #ffffff;
  --color-bg-subtle: #f8f9fa;
  --color-bg-muted: #e9ecef;
  --color-text: #1f2937;
  --color-text-muted: #6b7280;
  --color-text-light: #9ca3af;
  --color-border: #e5e7eb;
  
  --color-accent: #2a5a8a;
  --color-accent-hover: #1d4060;
  --color-accent-soft: #e8f0f7;
  --color-accent-dark: #3d7ab5;
  
  --color-Tracking: #dbeafe;
  --color-Revision: #bbf7d0;
  --color-Status: #fde68a;
  --color-Title: #f3f4f6;
}

/* ── Responsive (tablet) ── */
@media (max-width: 900px) {
  .ref-layout { gap: var(--spacing-xl); }
}

/* ── Releases page components ─────────────────────────── */
/* Used by website/releases/index.html (rendered by build.sh).
   Reuses existing tokens; adds nothing to the design system that
   isn't load-bearing for the install + version-pinning narrative. */

.version-picker-bar {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm) var(--spacing-md);
  background: var(--color-bg-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin: var(--spacing-md) 0 var(--spacing-lg);
  font-size: 0.95rem;
}
.version-picker-bar label { color: var(--color-text-muted); margin-right: var(--spacing-xs); }
.version-picker-bar select {
  font: inherit;
  padding: 0.25rem 0.5rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-bg);
  color: var(--color-text);
  cursor: pointer;
}
.version-picker-bar select:hover { border-color: var(--color-accent); }
.version-picker-bar .picker-hint { color: var(--color-text-muted); margin-left: auto; font-size: 0.875rem; }

.dl-primary {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: 0.85rem 1.5rem;
  background: var(--color-accent);
  color: #fff;
  text-decoration: none;
  font-weight: 600;
  font-size: 1.05rem;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-md);
  transition: background 0.15s, box-shadow 0.15s, transform 0.05s;
}
.dl-primary:hover { background: var(--color-accent-hover); box-shadow: var(--shadow-lg); }
.dl-primary:active { transform: translateY(1px); }
.dl-primary .dl-icon { font-size: 1.2em; line-height: 1; }
.dl-primary-meta {
  display: block;
  margin-top: var(--spacing-xs);
  color: var(--color-text-muted);
  font-size: 0.875rem;
  font-family: var(--font-mono);
}

.dl-secondary-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm) var(--spacing-md);
  margin-top: var(--spacing-md);
  font-size: 0.92rem;
  color: var(--color-text-muted);
}
.dl-secondary-row > span { color: var(--color-text-muted); }
.dl-secondary-row a {
  color: var(--color-text);
  text-decoration: none;
  padding: 0.2rem 0.5rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
  background: var(--color-bg);
}
.dl-secondary-row a:hover { background: var(--color-accent-soft); border-color: var(--color-accent); color: var(--color-accent); }

.pin-card {
  background: var(--color-bg-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--spacing-md) var(--spacing-lg);
}
.pin-card h3 {
  font-size: 1rem;
  margin: 0 0 var(--spacing-sm);
  color: var(--color-accent);
}
.pin-card p { margin: var(--spacing-sm) 0; color: var(--color-text); }
.pin-card pre {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: var(--spacing-sm) var(--spacing-md);
  margin: var(--spacing-sm) 0;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  overflow-x: auto;
  color: var(--color-text);
}
.pin-card code { font-family: var(--font-mono); font-size: 0.85em; padding: 0.05rem 0.3rem; background: var(--color-bg); border: 1px solid var(--color-border); border-radius: var(--radius-sm); }
.pin-note {
  margin-top: var(--spacing-md);
  padding: var(--spacing-sm) var(--spacing-md);
  background: var(--color-accent-soft);
  border-left: 3px solid var(--color-accent);
  border-radius: var(--radius-sm);
  color: var(--color-text);
  font-size: 0.95rem;
}

/* Channel explainer (bottom of the page) */
.channel-explainer { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--spacing-md); margin-top: var(--spacing-md); }
.channel-explainer > div {
  padding: var(--spacing-md);
  background: var(--color-bg-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}
.channel-explainer h4 { margin: 0 0 var(--spacing-xs); font-size: 0.95rem; }
.channel-explainer h4.alpha  { color: var(--color-text-muted); }
.channel-explainer h4.beta   { color: var(--color-text); }
.channel-explainer h4.stable { color: var(--color-accent); }
.channel-explainer p { margin: 0; font-size: 0.875rem; color: var(--color-text-muted); }

@media (max-width: 700px) {
  .channel-explainer { grid-template-columns: 1fr; }
  .dl-primary { width: 100%; justify-content: center; }
}