:root {
  --ink-950: #0b0e14;
  --ink-900: #10141d;
  --ink-800: #171d29;
  --ink-700: #232a3a;
  --paper-100: #eae5d8;
  --paper-300: #cfc9b8;
  --slate-400: #8891a3;
  --brass-300: #e3c878;
  --brass-500: #c9a24b;
  --brass-700: #8f6f2f;

  --font-display: "Source Serif 4", Georgia, serif;
  --font-body: "Inter", -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, monospace;

  --measure: 42rem;
  --gutter: clamp(1.25rem, 5vw, 4rem);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  * {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

body {
  margin: 0;
  background: var(--ink-950);
  color: var(--paper-100);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--brass-300);
  text-decoration-color: rgba(227, 200, 120, 0.4);
  text-underline-offset: 3px;
}

a:hover {
  color: var(--brass-500);
}

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--brass-300);
  outline-offset: 3px;
}

/* ---------- Header / Table of Contents ---------- */

.masthead {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(11, 14, 20, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--ink-700);
}

.masthead-inner {
  max-width: 68rem;
  margin: 0 auto;
  padding: 1rem var(--gutter);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
}

.wordmark {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--paper-100);
  text-decoration: none;
  white-space: nowrap;
}

.wordmark span {
  color: var(--brass-500);
}

.contents-nav {
  display: flex;
  gap: 1.25rem;
  overflow-x: auto;
  scrollbar-width: none;
  list-style: none;
  margin: 0;
  padding: 0;
}

.contents-nav::-webkit-scrollbar {
  display: none;
}

.contents-nav a {
  display: inline-flex;
  align-items: baseline;
  gap: 0.4em;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--slate-400);
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.15s ease;
}

.contents-nav a:hover,
.contents-nav a:focus-visible {
  color: var(--brass-300);
}

.contents-nav .num {
  color: var(--brass-700);
}

/* ---------- Hero ---------- */

.hero {
  max-width: 68rem;
  margin: 0 auto;
  padding: clamp(4rem, 12vw, 8rem) var(--gutter) clamp(3rem, 8vw, 5rem);
}

.hero-eyebrow {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--brass-500);
  margin: 0 0 1.5rem;
}

.hero h1 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(2.4rem, 6vw, 4.2rem);
  line-height: 1.08;
  letter-spacing: -0.01em;
  max-width: 18ch;
  margin: 0 0 1.75rem;
  color: var(--paper-100);
}

.hero-sub {
  max-width: 42rem;
  font-size: 1.15rem;
  color: var(--paper-300);
  margin: 0 0 0.5rem;
}

.hero-note {
  max-width: 42rem;
  font-size: 0.95rem;
  color: var(--slate-400);
  border-left: 2px solid var(--brass-700);
  padding-left: 1rem;
  margin-top: 2rem;
}

/* ---------- Sections ---------- */

.chapter {
  border-top: 1px solid var(--ink-700);
  padding: clamp(3rem, 8vw, 5rem) var(--gutter);
}

.chapter-inner {
  max-width: 68rem;
  margin: 0 auto;
  display: grid;
  grid-template-columns: minmax(0, 9rem) minmax(0, var(--measure));
  gap: clamp(1.5rem, 4vw, 4rem);
}

.chapter-marker {
  font-family: var(--font-mono);
  color: var(--brass-700);
}

.chapter-marker .num {
  display: block;
  font-size: 2.4rem;
  line-height: 1;
  color: var(--brass-500);
}

.chapter-marker .label {
  display: block;
  margin-top: 0.5rem;
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--slate-400);
}

.chapter h2 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(1.6rem, 3.2vw, 2.1rem);
  margin: 0 0 1.25rem;
  color: var(--paper-100);
}

.chapter p {
  color: var(--paper-300);
  margin: 0 0 1.1rem;
}

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

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: 1.5rem;
}

.tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  color: var(--paper-300);
  border: 1px solid var(--ink-700);
  border-radius: 3px;
  padding: 0.35rem 0.65rem;
}

/* ---------- Product: shelf (horizontal scroll gallery) ---------- */

.shelf-wrap {
  position: relative;
  margin-top: 2.25rem;
  /* let the shelf bleed to the viewport edge while text stays in-measure */
  margin-left: calc(-1 * var(--gutter));
  margin-right: calc(-1 * var(--gutter));
}

/* Fade the trailing edge so a partially visible card reads as "more to
   scroll", not a layout error. */
.shelf-wrap::after {
  content: "";
  position: absolute;
  top: 0.5rem;
  bottom: 1.25rem;
  right: 0;
  width: clamp(2rem, 6vw, 4.5rem);
  background: linear-gradient(to right, transparent, var(--ink-950) 88%);
  pointer-events: none;
}

.shelf {
  display: flex;
  gap: 1.1rem;
  overflow-x: auto;
  scroll-snap-type: x proximity;
  padding: 0.5rem var(--gutter) 1.25rem;
  scrollbar-width: thin;
  scrollbar-color: var(--brass-700) transparent;
}

.shelf-item {
  scroll-snap-align: start;
  flex: 0 0 auto;
  width: clamp(13rem, 30vw, 19rem);
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.shelf-item img {
  display: block;
  width: 100%;
  height: clamp(17.5rem, 40vw, 25.5rem);
  object-fit: cover;
  border-radius: 3px;
  border: 1px solid var(--ink-700);
  background: var(--ink-800);
  box-shadow: 0 12px 24px -12px rgba(0, 0, 0, 0.6);
}

.shelf-item.is-wide img {
  object-fit: contain;
  background: #f4f1ea;
}

.shelf-caption {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.03em;
  color: var(--slate-400);
}

.shelf-controls {
  display: flex;
  justify-content: flex-end;
  gap: 0.5rem;
  padding: 0 var(--gutter) 0.6rem;
}

.shelf-btn {
  width: 2rem;
  height: 2rem;
  border-radius: 50%;
  border: 1px solid var(--ink-700);
  background: var(--ink-900);
  color: var(--paper-100);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: border-color 0.15s ease, color 0.15s ease;
}

.shelf-btn:hover {
  border-color: var(--brass-500);
  color: var(--brass-300);
}

/* ---------- Track record: ledger list ---------- */

.ledger {
  margin: 1.75rem 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--ink-700);
}

.ledger li {
  display: flex;
  justify-content: space-between;
  gap: 1.5rem;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--ink-700);
  font-size: 0.95rem;
}

.ledger .client {
  color: var(--paper-100);
}

.ledger .scope {
  color: var(--slate-400);
  text-align: right;
  font-size: 0.85rem;
}

.cert-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: 1.75rem;
}

/* ---------- Why GPT-5.5: two-column comparison ---------- */

.ask-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
  margin-top: 1.75rem;
}

@media (min-width: 640px) {
  .ask-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.ask-card {
  border: 1px solid var(--ink-700);
  border-radius: 4px;
  padding: 1.25rem 1.4rem;
  background: var(--ink-900);
}

.ask-card h3 {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--brass-500);
  margin: 0 0 0.75rem;
}

.ask-card p {
  font-size: 0.92rem;
  margin: 0;
  color: var(--paper-300);
}

/* ---------- Leadership ---------- */

.leadership-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
  margin-top: 0.5rem;
}

@media (min-width: 640px) {
  .leadership-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.leader-card {
  border: 1px solid var(--ink-700);
  border-radius: 4px;
  padding: 1.75rem;
  background: var(--ink-900);
}

.leader-role {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--brass-500);
  margin: 0 0 0.5rem;
}

.leader-card h3 {
  font-family: var(--font-display);
  font-size: 1.35rem;
  margin: 0 0 0.85rem;
  color: var(--paper-100);
}

.leader-card p {
  font-size: 0.92rem;
  color: var(--paper-300);
  margin: 0;
}

.leader-link {
  display: inline-block;
  margin-top: 1rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
}

/* ---------- Contact ---------- */

.contact-block {
  margin-top: 1.5rem;
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.contact-email {
  font-family: var(--font-mono);
  font-size: 1.1rem;
}

/* ---------- Colophon ---------- */

.colophon {
  border-top: 1px solid var(--ink-700);
  padding: 2.5rem var(--gutter) 3.5rem;
}

.colophon-inner {
  max-width: 68rem;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  color: var(--slate-400);
}

@media (max-width: 640px) {
  .chapter-inner {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  .chapter-marker {
    display: flex;
    align-items: baseline;
    gap: 0.6rem;
  }

  .chapter-marker .num {
    font-size: 1.4rem;
  }

  .chapter-marker .label {
    margin-top: 0;
  }

  .masthead-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.75rem;
  }

  .contents-nav {
    width: 100%;
  }

  .ledger li {
    flex-direction: column;
    gap: 0.15rem;
  }

  .ledger .scope {
    text-align: left;
  }
}