:root {
  --bg: #0f1724;
  --surface: #0b1220;
  --surface-2: #111a2b;
  --border: rgba(255, 255, 255, 0.08);
  --muted: #9aa4b2;
  --text: #e6eef6;
  --accent: #3b82f6;
  --accent-strong: #0b5fff;
  --shadow: 0 24px 60px rgba(0, 0, 0, 0.18);
  --radius: 16px;
  --max-width: 1120px;
}

:root.light {
  --bg: #f7fafc;
  --surface: #ffffff;
  --surface-2: #eef3f8;
  --border: rgba(15, 23, 36, 0.08);
  --muted: #475569;
  --text: #0f1724;
  --accent: #0b5fff;
  --accent-strong: #0844c4;
  --shadow: 0 18px 40px rgba(15, 23, 36, 0.08);
}

html {
  color-scheme: dark light;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  background:
    radial-gradient(circle at top, rgba(59, 130, 246, 0.14), transparent 40%),
    var(--bg);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
  line-height: 1.6;
}

img {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
}

.container {
  width: min(var(--max-width), calc(100% - 2rem));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  border-bottom: 1px solid var(--border);
  background: rgba(10, 16, 28, 0.82);
  backdrop-filter: blur(12px);
}

:root.light .site-header {
  background: rgba(247, 250, 252, 0.86);
}

.site-header__inner,
.site-footer__inner {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem 0;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  min-width: fit-content;
}

.logo {
  width: 40px;
  height: 40px;
}

.name {
  font-weight: 650;
  letter-spacing: 0.01em;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
  margin-left: auto;
}

.nav a {
  color: var(--muted);
  text-decoration: none;
  padding: 0.55rem 0.75rem;
  border-radius: 999px;
  transition:
    color 0.15s ease,
    background-color 0.15s ease;
}

.nav a:hover,
.nav a:focus-visible {
  color: var(--text);
  background: var(--surface-2);
}

.nav a[aria-current="page"] {
  color: var(--text);
  background: var(--surface-2);
  box-shadow: inset 0 0 0 1px var(--border);
}

.actions {
  display: flex;
  align-items: center;
}

#theme-toggle {
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 999px;
  cursor: pointer;
  box-shadow: var(--shadow);
}

#theme-toggle:hover,
#theme-toggle:focus-visible {
  border-color: color-mix(in srgb, var(--accent) 45%, var(--border));
}

.page {
  padding: 2.5rem 0 4rem;
}

.page--book {
  padding-bottom: 5rem;
}

.page-header {
  display: grid;
  gap: 1rem;
  margin-bottom: 2rem;
  max-width: 48rem;
}

.eyebrow,
.meta {
  color: var(--muted);
  font-size: 0.95rem;
  margin: 0;
}

.page-header h1,
.hero h1 {
  margin: 0;
  line-height: 1.08;
  letter-spacing: -0.03em;
}

.page-header h1 {
  font-size: clamp(2rem, 5vw, 3.4rem);
}

.hero {
  padding: 1rem 0 2rem;
}

.hero-grid,
.split {
  display: grid;
  gap: 1.5rem;
  align-items: start;
}

.hero-grid {
  grid-template-columns: 1fr;
}

.hero h1 {
  font-size: clamp(2.2rem, 6vw, 4rem);
  max-width: 12ch;
}

.book-hero {
  display: grid;
  gap: 1.5rem;
  align-items: start;
  margin-bottom: 2rem;
}

.book-hero__content {
  display: grid;
  gap: 1rem;
  align-content: start;
  max-width: 50rem;
}

.lead {
  margin: 1rem 0 0;
  color: var(--muted);
  max-width: 40rem;
  font-size: 1.05rem;
}

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.8rem 1rem;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 600;
  border: 1px solid transparent;
}

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

.btn.primary:hover,
.btn.primary:focus-visible {
  background: var(--accent-strong);
}

.btn.outline {
  border-color: var(--border);
  color: var(--text);
  background: transparent;
}

.btn.outline:hover,
.btn.outline:focus-visible {
  background: var(--surface-2);
}

.page-grid,
.highlights {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}

.section {
  margin-top: 2rem;
}

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

.section__heading {
  display: grid;
  gap: 0.35rem;
  margin: 0 0 1rem;
}

.section__heading h2 {
  margin: 0;
  font-size: 1.35rem;
  letter-spacing: -0.02em;
}

.section__heading p {
  margin: 0;
  color: var(--muted);
}

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

.section-grid--two {
  grid-template-columns: 1fr;
}

.section-grid--three {
  grid-template-columns: 1fr;
}

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

.card h2,
.card h3 {
  margin-top: 0;
  margin-bottom: 0.5rem;
}

.card p:last-child,
.card ul:last-child {
  margin-bottom: 0;
}

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

.link:hover,
.link:focus-visible {
  text-decoration: underline;
}

.hero-figure {
  margin: 0;
  justify-self: start;
}

.hero-figure img {
  width: min(100%, 280px);
  border-radius: calc(var(--radius) - 2px);
  box-shadow: var(--shadow);
}

.hero-figure figcaption {
  margin-top: 0.75rem;
  color: var(--muted);
  font-size: 0.95rem;
}

.media-card {
  padding: 0;
  overflow: hidden;
}

.media-card img {
  width: 100%;
  height: auto;
}

.media-card .card-body {
  padding: 1.25rem;
}

.book-cover {
  margin: 0;
  width: min(100%, 320px);
  border-radius: calc(var(--radius) - 2px);
  overflow: hidden;
  box-shadow: none;
}

.book-cover img {
  width: 100%;
  height: auto;
  border-radius: 0;
}

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

.stack--wide {
  gap: 1.25rem;
}

.list {
  padding-left: 1.15rem;
  margin: 0;
}

.list li + li {
  margin-top: 0.4rem;
}

.site-footer {
  border-top: 1px solid var(--border);
  margin-top: 2rem;
}

.site-footer__inner {
  flex-wrap: wrap;
  justify-content: space-between;
}

.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.site-footer nav a {
  color: var(--muted);
  text-decoration: none;
}

.site-footer nav a:hover,
.site-footer nav a:focus-visible {
  color: var(--text);
}

.copyright {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

@media (min-width: 720px) {
  .hero-grid,
  .split {
    grid-template-columns: minmax(0, 1.5fr) minmax(240px, 0.9fr);
    align-items: center;
  }

  .book-hero {
    grid-template-columns: minmax(280px, 320px) minmax(0, 1fr);
    align-items: start;
    gap: 2rem;
  }

  .book-hero__content {
    padding-top: 0.25rem;
  }

  .section-grid--two {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .section-grid--three {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .highlights {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (max-width: 680px) {
  .site-header__inner,
  .site-footer__inner {
    align-items: flex-start;
  }

  .nav {
    margin-left: 0;
  }
}

/* Enterprise Intelligence Architecture book page */
.eia-page {
  --eia-rule: color-mix(in srgb, var(--text) 14%, transparent);
  --eia-soft: color-mix(in srgb, var(--surface-2) 78%, transparent);
}

.eia-hero {
  padding: clamp(2.5rem, 7vw, 6rem) 0;
  border-bottom: 1px solid var(--eia-rule);
}

.eia-hero__grid {
  display: grid;
  grid-template-columns: minmax(200px, 280px) minmax(0, 1fr);
  gap: clamp(2.5rem, 7vw, 6.5rem);
  align-items: center;
}

.eia-cover {
  margin: 0;
  width: min(100%, 280px);
}

.eia-cover img {
  width: 100%;
  height: auto;
  border-radius: 6px;
  box-shadow:
    0 2px 6px rgba(0, 0, 0, 0.2),
    0 28px 70px rgba(0, 0, 0, 0.34);
}

.eia-hero__content {
  max-width: 46rem;
}

.eia-kicker {
  margin: 0 0 1rem;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  line-height: 1.4;
  text-transform: uppercase;
}

.eia-hero h1 {
  margin: 0;
  max-width: 13ch;
  font-size: clamp(2.65rem, 6.2vw, 5.4rem);
  letter-spacing: -0.055em;
  line-height: 0.98;
}

.eia-subtitle {
  margin: 1.5rem 0 0;
  max-width: 35rem;
  color: var(--text);
  font-size: clamp(1.15rem, 2vw, 1.45rem);
  line-height: 1.45;
}

.eia-summary {
  margin: 1.25rem 0 0;
  max-width: 42rem;
  color: var(--muted);
  font-size: 1rem;
}

.eia-byline {
  margin: 1.5rem 0 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.eia-byline a,
.eia-inline-links a,
.eia-reference-grid a {
  color: var(--text);
  text-decoration-color: color-mix(in srgb, var(--accent) 60%, transparent);
  text-underline-offset: 0.2em;
}

.eia-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.75rem;
}

.eia-release-note {
  margin: 1rem 0 0;
  color: var(--muted);
  font-size: 0.82rem;
}

.eia-contents {
  position: sticky;
  top: 73px;
  z-index: 20;
  border-bottom: 1px solid var(--eia-rule);
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(12px);
}

.eia-contents__inner {
  display: flex;
  gap: 1.5rem;
  align-items: center;
  min-height: 3.5rem;
  overflow-x: auto;
  scrollbar-width: none;
}

.eia-contents__inner::-webkit-scrollbar {
  display: none;
}

.eia-contents span,
.eia-contents a {
  flex: 0 0 auto;
  font-size: 0.82rem;
}

.eia-contents span {
  color: var(--muted);
}

.eia-contents a {
  color: var(--text);
  text-decoration: none;
}

.eia-contents a:hover,
.eia-contents a:focus-visible {
  color: var(--accent);
}

.eia-content {
  padding-bottom: clamp(4rem, 8vw, 7rem);
}

.eia-section {
  display: grid;
  grid-template-columns: minmax(150px, 0.42fr) minmax(0, 1.58fr);
  gap: clamp(2rem, 6vw, 6rem);
  padding: clamp(3.5rem, 7vw, 6.5rem) 0;
  border-bottom: 1px solid var(--eia-rule);
  scroll-margin-top: 9rem;
}

.eia-section__label p {
  margin: 0 0 0.55rem;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.12em;
}

.eia-section__label h2 {
  margin: 0;
  font-size: clamp(1.25rem, 2vw, 1.6rem);
  letter-spacing: -0.025em;
  line-height: 1.2;
}

.eia-prose {
  max-width: 49rem;
}

.eia-prose > :first-child {
  margin-top: 0;
}

.eia-intro {
  max-width: 42rem;
  margin-bottom: 1.25rem;
  color: var(--text);
  font-size: clamp(1.25rem, 2.4vw, 1.7rem);
  letter-spacing: -0.025em;
  line-height: 1.4;
}

.eia-prose > p:not(.eia-intro, .eia-kicker) {
  color: var(--muted);
}

.eia-problem {
  margin-top: 2.25rem;
  padding: 1.5rem;
  border-left: 3px solid var(--accent);
  background: var(--eia-soft);
}

.eia-problem h3,
.eia-featured-resource h3,
.eia-reference-grid h3,
.eia-key-topics h3 {
  margin: 0 0 0.6rem;
  font-size: 1rem;
}

.eia-problem p {
  margin: 0;
  color: var(--muted);
}

.eia-audience-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0;
  margin: 2rem 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--eia-rule);
}

.eia-audience-list li {
  display: grid;
  gap: 0.4rem;
  padding: 1.35rem 1.25rem 1.35rem 0;
  border-bottom: 1px solid var(--eia-rule);
}

.eia-audience-list li:nth-child(even) {
  padding-right: 0;
  padding-left: 1.25rem;
  border-left: 1px solid var(--eia-rule);
}

.eia-audience-list span {
  color: var(--muted);
  font-size: 0.92rem;
}

.eia-topic-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin-top: 2.25rem;
  border-top: 1px solid var(--eia-rule);
  border-left: 1px solid var(--eia-rule);
}

.eia-topic-grid article {
  padding: 1.5rem;
  border-right: 1px solid var(--eia-rule);
  border-bottom: 1px solid var(--eia-rule);
}

.eia-topic-grid span {
  color: var(--accent);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.eia-topic-grid h3 {
  margin: 0.65rem 0 0.5rem;
  font-size: 1rem;
}

.eia-topic-grid p {
  margin: 0;
  color: var(--muted);
  font-size: 0.9rem;
}

.eia-key-topics {
  margin-top: 2.25rem;
}

.eia-key-topics ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.eia-key-topics li {
  padding: 0.45rem 0.7rem;
  border: 1px solid var(--eia-rule);
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.8rem;
}

.eia-featured-resource {
  margin-top: 2.25rem;
  padding: clamp(1.5rem, 4vw, 2.25rem);
  border: 1px solid var(--eia-rule);
  background: var(--eia-soft);
}

.eia-featured-resource .eia-kicker {
  margin-bottom: 0.7rem;
}

.eia-featured-resource h3 {
  font-size: 1.35rem;
}

.eia-featured-resource > p:not(.eia-kicker) {
  max-width: 42rem;
  margin-bottom: 0;
  color: var(--muted);
}

.eia-inline-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  margin-top: 1.5rem;
  font-size: 0.9rem;
  font-weight: 650;
}

.eia-reference-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin-top: 1.25rem;
  border-top: 1px solid var(--eia-rule);
  border-left: 1px solid var(--eia-rule);
}

.eia-reference-grid article {
  padding: 1.5rem;
  border-right: 1px solid var(--eia-rule);
  border-bottom: 1px solid var(--eia-rule);
  scroll-margin-top: 9rem;
}

.eia-reference-grid ul {
  margin: 0;
  padding-left: 1.1rem;
  color: var(--muted);
  font-size: 0.9rem;
}

.eia-reference-grid li + li {
  margin-top: 0.45rem;
}

.eia-release {
  margin: 0;
}

.eia-release div {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.4rem 0;
  border-bottom: 1px solid var(--eia-rule);
  font-size: 0.86rem;
}

.eia-release div:last-child {
  border-bottom: 0;
}

.eia-release dt {
  color: var(--muted);
}

.eia-release dd {
  margin: 0;
  text-align: right;
}

@media (max-width: 760px) {
  .eia-hero {
    padding: 2.5rem 0 3.5rem;
  }

  .eia-hero__grid {
    grid-template-columns: minmax(130px, 38vw) minmax(0, 1fr);
    gap: 1.5rem;
    align-items: start;
  }

  .eia-hero h1 {
    font-size: clamp(2rem, 8vw, 3.2rem);
  }

  .eia-subtitle {
    margin-top: 1rem;
    font-size: 1rem;
  }

  .eia-summary {
    grid-column: 1 / -1;
  }

  .eia-contents {
    top: 0;
  }

  .eia-section {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}

@media (max-width: 560px) {
  .eia-site .site-header__inner {
    flex-wrap: wrap;
    align-items: center;
  }

  .eia-site .actions {
    margin-left: auto;
  }

  .eia-site .nav {
    order: 3;
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    width: 100%;
  }

  .eia-site .nav a {
    padding: 0.45rem 0.25rem;
    text-align: center;
  }

  .eia-hero__grid {
    grid-template-columns: 1fr;
  }

  .eia-cover {
    width: min(50vw, 200px);
  }

  .eia-summary {
    grid-column: auto;
  }

  .eia-actions {
    display: grid;
  }

  .eia-actions .btn {
    width: auto;
  }

  .eia-audience-list,
  .eia-topic-grid,
  .eia-reference-grid {
    grid-template-columns: 1fr;
  }

  .eia-audience-list li:nth-child(even) {
    padding-left: 0;
    border-left: 0;
  }
}