:root {
  color-scheme: light;
  /* Canonical ADL brand and surface tokens, from adl-spec.html §02. */
  --as-marine: #075156; --as-marine-hover: #008080; --as-green: #2C8248;
  --as-citrus: #ABDD65; --as-navy: #17232D; --as-pale-blue: #E5EEEF;
  --as-font-display: 'Chronicle Display', Georgia, 'Times New Roman', serif;
  --as-font-body: 'Montserrat', 'Helvetica Neue', Arial, sans-serif;
  --paper: #F2F7F7; --surface: #FFFFFF; --sunk: #E5EEEF; --raise: #FFFFFF;
  --ink: #17232D; --ink-2: #3A434D; --ink-3: #4D5A66; --ink-4: #667682;
  --rule: #CCD2D6; --rule-2: #A6B5BD;
  --accent: #075156; --accent-hover: #008080; --accent-strong: #075156; --accent-soft: #E5EEEF;
  --focus: #075156; --ok: #2e7d32; --warn: #c77700; --danger: #b3261e; --info: #1d70b8;
  --muted: #6b7785; --neutral: #37474f; --flow: var(--accent); --flow-2: var(--accent-hover);
  --lean: var(--as-citrus); --card: var(--raise); --line: var(--rule); --wash: var(--sunk);
  --navy: var(--as-navy); --hero-ink: #FFFFFF;
  --sh-1: 0 1px 2px rgb(23 35 45 / 8%); --sh-2: 0 2px 6px rgb(23 35 45 / 10%), 0 12px 28px -14px rgb(23 35 45 / 28%);
  --shadow: var(--sh-2);
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --paper: #17232D; --surface: #2A323A; --sunk: #2A323A; --raise: #3A434D;
  --ink: #F5F6F7; --ink-2: #CCD2D6; --ink-3: #A9B4BD; --ink-4: #667682;
  --rule: #3A434D; --rule-2: #4D5A66; --accent: #4DB8B8; --accent-hover: #80CCCC;
  --accent-strong: #80CCCC; --accent-soft: color-mix(in srgb, #4DB8B8 20%, #17232D);
  --focus: var(--as-citrus); --ok: #6cbf72; --warn: #e2a53f; --danger: #e8756c;
  --info: #63a4e0; --muted: #9aa3ae; --neutral: #b6bec4; --flow: var(--accent);
  --flow-2: var(--accent-hover); --card: var(--raise); --line: var(--rule); --wash: var(--sunk);
  --navy: var(--as-navy); --hero-ink: #F5F6F7; --shadow: none; --sh-1: none; --sh-2: none;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) { color-scheme: dark; --paper: #17232D; --surface: #2A323A; --sunk: #2A323A; --raise: #3A434D; --ink: #F5F6F7; --ink-2: #CCD2D6; --ink-3: #A9B4BD; --ink-4: #667682; --rule: #3A434D; --rule-2: #4D5A66; --accent: #4DB8B8; --accent-hover: #80CCCC; --accent-strong: #80CCCC; --accent-soft: color-mix(in srgb, #4DB8B8 20%, #17232D); --focus: var(--as-citrus); --ok: #6cbf72; --warn: #e2a53f; --danger: #e8756c; --info: #63a4e0; --muted: #9aa3ae; --neutral: #b6bec4; --flow: var(--accent); --flow-2: var(--accent-hover); --card: var(--raise); --line: var(--rule); --wash: var(--sunk); --navy: var(--as-navy); --hero-ink: #F5F6F7; --shadow: none; --sh-1: none; --sh-2: none; }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; min-width: 320px; background: var(--surface); color: var(--ink); font: 16px/1.6 "Segoe UI", system-ui, sans-serif; }
a { color: inherit; }
.site-header, main, .site-footer { width: min(1160px, calc(100% - 40px)); margin-inline: auto; }
.site-header { display: flex; align-items: center; gap: 28px; padding: 22px 0; }
.brand { display: inline-flex; align-items: center; margin-right: auto; }
.brand-logo { display: block; width: 154px; height: auto; }
.dark-logo { display: none; }
:root[data-theme="dark"] .light-logo { display: none; }
:root[data-theme="dark"] .dark-logo { display: block; }
@media (prefers-color-scheme: dark) { :root:not([data-theme="light"]) .light-logo { display: none; } :root:not([data-theme="light"]) .dark-logo { display: block; } }
.site-nav { display: flex; align-items: center; gap: 24px; color: var(--muted); font-size: .9rem; }
.site-nav a { text-decoration: none; }
.site-nav a:hover, .site-nav a:focus-visible, .text-link:hover, .text-link:focus-visible { color: var(--flow); }
.header-action { border: 0; background: none; color: var(--muted); padding: 7px 0; cursor: pointer; font: inherit; font-size: .82rem; }
.header-action:hover, .header-action:focus-visible { color: var(--flow); }
.theme-toggle { display: inline-flex; gap: 7px; align-items: center; border: 1px solid var(--line); border-radius: 99px; background: var(--card); color: var(--muted); padding: 7px 11px; cursor: pointer; font: inherit; font-size: .78rem; }
.theme-toggle:hover { border-color: var(--flow); color: var(--flow); }
button, a { transition: color 150ms ease, background-color 150ms ease, border-color 150ms ease, transform 150ms ease; }
.hero { display: grid; grid-template-columns: minmax(0, .92fr) minmax(360px, 1.08fr); min-height: 550px; overflow: hidden; border-radius: 12px; background: var(--navy); color: var(--hero-ink); box-shadow: var(--shadow); }
.hero-copy { display: flex; flex-direction: column; justify-content: center; padding: clamp(38px, 7vw, 88px); }
.eyebrow, .card-kicker { margin: 0 0 12px; color: var(--lean); font-size: .72rem; font-weight: 700; letter-spacing: .13em; text-transform: uppercase; }
h1, h2, p { margin-top: 0; }
h1 { max-width: 650px; margin-bottom: 20px; font: 400 clamp(2.9rem, 6vw, 5.2rem)/.98 Georgia, "Times New Roman", serif; letter-spacing: -.055em; }
h2 { margin-bottom: 10px; font: 500 clamp(1.35rem, 2vw, 1.85rem)/1.12 Georgia, "Times New Roman", serif; letter-spacing: -.025em; }
.lede { max-width: 590px; margin-bottom: 28px; color: var(--muted); font-size: 1.1rem; }
.hero .lede { color: color-mix(in srgb, var(--hero-ink) 76%, var(--navy)); }
.hero-actions { display: flex; align-items: center; flex-wrap: wrap; gap: 18px; }
.hero-art { min-height: 420px; background: url("/brand/hero.jpg") center / cover no-repeat; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 44px; border: 1px solid transparent; border-radius: 5px; padding: 10px 17px; font-weight: 700; text-decoration: none; cursor: pointer; }
.button-primary { background: var(--lean); color: var(--as-navy); }
.button-primary:hover, .button-primary:focus-visible { background: color-mix(in srgb, var(--lean) 82%, white); transform: translateY(-1px); }
.button-secondary { border-color: var(--line); background: var(--card); color: var(--ink); }
.text-link { color: color-mix(in srgb, var(--hero-ink) 82%, var(--navy)); font-size: .92rem; text-decoration: none; }
.inline-form { display: inline-flex; }
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px; margin: 52px 0; border-block: 1px solid var(--line); background: var(--line); }
.stats div { display: flex; flex-direction: column; gap: 2px; background: var(--surface); padding: 20px 18px; }
.stats strong { color: var(--flow); font: 500 2rem/1 Georgia, serif; }
.stats span, dt { color: var(--muted); font-size: .77rem; letter-spacing: .08em; text-transform: uppercase; }
.overview-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; margin-bottom: 90px; }
.surface-card, .note-card, .release-row { border: 1px solid var(--line); border-radius: 8px; background: var(--card); }
.surface-card { min-height: 220px; padding: 30px; }
.surface-card p:last-child { max-width: 480px; margin-bottom: 0; color: var(--muted); }
.page-intro { padding: 66px 0 40px; }
.page-intro h1, .error-page h1 { max-width: 760px; font-size: clamp(2.6rem, 5vw, 4.4rem); }
.download-bar { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin-top: 34px; padding: 18px 20px; border: 1px solid var(--line); border-radius: 8px; background: var(--card); box-shadow: var(--shadow); }
.download-bar div { display: flex; flex-direction: column; gap: 3px; }
.download-bar span { color: var(--muted); font-size: .8rem; }
.download-status { min-height: 1.2em; }
.download-bar details { margin-top: 6px; color: var(--muted); font-size: .76rem; }
.download-bar summary { cursor: pointer; }
.hash { display: block; max-width: 100%; color: var(--muted); font: .72rem/1.5 ui-monospace, Consolas, monospace; overflow-wrap: anywhere; }
.guide-list { display: grid; gap: 2px; margin-bottom: 28px; border-top: 1px solid var(--line); }
.guide-section { display: grid; grid-template-columns: 80px minmax(0, 1fr); gap: 24px; padding: 28px 0; border-bottom: 1px solid var(--line); }
.section-number { color: var(--flow); font: 500 1.4rem/1 Georgia, serif; }
.guide-section h2 { margin-bottom: 13px; }
.guide-section ol { display: grid; gap: 8px; margin: 0; padding-left: 20px; color: var(--muted); }
.guide-section li::marker { color: var(--flow); font-weight: 700; }
.note-card { display: flex; gap: 14px; align-items: baseline; margin-bottom: 80px; padding: 18px 20px; color: var(--muted); }
.note-card strong { color: var(--ink); }
.release-row { display: flex; justify-content: space-between; gap: 30px; padding: 28px; margin-bottom: 100px; }
.release-row h2 { margin: 0; font-size: 2.5rem; }
.release-row dl { display: flex; flex-wrap: wrap; gap: 22px; margin: 0; }
.release-row dl div { min-width: 125px; }
.release-row dd { margin: 4px 0 0; color: var(--ink); font-size: .9rem; overflow-wrap: anywhere; }
.error-page { min-height: 62vh; padding: 100px 0; }
.site-footer { display: flex; justify-content: space-between; gap: 20px; padding: 22px 0 30px; border-top: 1px solid var(--line); color: var(--muted); font-size: .75rem; }
:focus-visible { outline: 2px solid var(--flow); outline-offset: 4px; }
@media (max-width: 760px) {
  .site-header, main, .site-footer { width: min(100% - 28px, 600px); }
  .site-header { gap: 14px; padding: 16px 0; }
  .brand-logo { width: 122px; }
  .site-nav { gap: 12px; font-size: .8rem; }
  .theme-toggle { padding-inline: 8px; }
  .theme-toggle span:last-child { display: none; }
  .hero { display: block; }
  .hero-copy { min-height: 440px; padding: 38px 26px; }
  .hero-art { min-height: 215px; }
  .stats { grid-template-columns: repeat(2, 1fr); margin: 34px 0; }
  .overview-grid { grid-template-columns: 1fr; margin-bottom: 52px; }
  .page-intro { padding: 42px 0 24px; }
  .download-bar, .release-row, .site-footer { align-items: flex-start; flex-direction: column; }
  .guide-section { grid-template-columns: 42px minmax(0, 1fr); gap: 12px; }
}
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; } }
@media (prefers-reduced-transparency: reduce) { .surface-card, .note-card, .release-row, .download-bar { background: var(--card); } }