/* ============================================================
   Frank Tsuro — Executive Advisor
   Rebuilt: natural smooth scroll · premium editorial · mobile-first
   ============================================================ */

/* ---- 1. Design tokens ------------------------------------ */
:root {
  --ink: #11110f;
  --ink-soft: #1b1b18;
  --ink-deep: #0d0d0b;
  --bone: #eee9dd;
  --paper: #f7f4ec;
  --paper-deep: #ded7c7;
  --copper: #b08a2e;
  --copper-dark: #7f5c20;
  --acid: #d4b24c;
  --acid-bright: #e4c25a;
  --muted: #77756d;

  --line-dark: rgba(23, 23, 19, 0.19);
  --line-light: rgba(247, 244, 236, 0.16);

  --font-display: "EB Garamond", Georgia, serif;
  --font-sans: "Inter", Arial, sans-serif;

  --gutter: clamp(1.35rem, 4vw, 4.5rem);
  --max: 90rem;

  --header-h: 4.5rem;          /* mobile header height   */
  --scroll-offset: 5rem;       /* anchor scroll padding  */

  --ease: cubic-bezier(0.2, 0.75, 0.25, 1);
}

/* ---- 2. Reset & base ------------------------------------- */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--scroll-offset);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  overflow-x: hidden;
  color: var(--ink);
  background: var(--bone);
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.55;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body.menu-open {
  overflow: hidden;
}

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

a {
  color: inherit;
  text-decoration: none;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

button:focus-visible,
a:focus-visible {
  outline: 2px solid var(--acid);
  outline-offset: 4px;
  border-radius: 2px;
}

h1, h2, h3, h4, p {
  overflow-wrap: break-word;
}

/* ---- 3. Utilities ---------------------------------------- */
.skip-link {
  position: fixed;
  z-index: 1000;
  top: 1rem;
  left: 1rem;
  padding: 0.8rem 1rem;
  color: var(--paper);
  background: var(--ink);
  transform: translateY(-180%);
  transition: transform 200ms var(--ease);
}
.skip-link:focus {
  transform: translateY(0);
}

.eyebrow {
  margin: 0 0 1.6rem;
  color: var(--copper-dark);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.17em;
  text-transform: uppercase;
}
.eyebrow--light {
  color: var(--acid);
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  min-width: min(15rem, 100%);
  max-width: 100%;
  padding: 1rem 1.2rem;
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  transition: color 200ms var(--ease), background 200ms var(--ease),
    transform 200ms var(--ease), box-shadow 200ms var(--ease);
}
.button:hover {
  transform: translateY(-3px);
}
.button--light {
  color: var(--ink);
  background: var(--acid);
}
.button--light:hover {
  background: var(--acid-bright);
  box-shadow: 0 14px 34px -18px rgba(212, 178, 76, 0.9);
}
.button--dark {
  color: var(--paper);
  background: var(--ink);
}
.button--dark:hover {
  background: var(--ink-soft);
  box-shadow: 0 16px 36px -20px rgba(17, 17, 15, 0.8);
}

.text-link {
  color: rgba(247, 244, 236, 0.72);
  font-size: 0.82rem;
  padding-bottom: 2px;
  border-bottom: 1px solid rgba(247, 244, 236, 0.35);
  transition: color 180ms var(--ease), border-color 180ms var(--ease);
}
.text-link:hover {
  color: var(--paper);
  border-color: var(--paper);
}

/* Reveal-on-scroll */
.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 640ms var(--ease), transform 640ms var(--ease);
}
.reveal.is-visible {
  opacity: 1;
  transform: none;
}

/* ---- 4. Scroll progress bar ------------------------------ */
.scroll-progress {
  position: fixed;
  z-index: 200;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: transparent;
  pointer-events: none;
}
.scroll-progress span {
  display: block;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, var(--copper), var(--acid));
  transform: scaleX(0);
  transform-origin: left;
}

/* ---- 5. Header + navigation ------------------------------ */
.site-header {
  position: fixed;
  z-index: 100;
  top: 0;
  left: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  height: var(--header-h);
  padding: 0 var(--gutter);
  color: var(--paper);
  border-bottom: 1px solid rgba(247, 244, 236, 0.1);
  background: rgba(23, 23, 19, 0.82);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  transition: height 280ms var(--ease), background 280ms var(--ease);
}
.site-header.is-scrolled {
  background: rgba(20, 20, 17, 0.95);
}

.wordmark {
  display: inline-flex;
  align-items: baseline;
  gap: 0.85rem;
  letter-spacing: -0.01em;
}
.wordmark__name {
  font-family: var(--font-display);
  font-size: 1.4rem;
}
.wordmark__role {
  color: rgba(247, 244, 236, 0.55);
  font-size: 0.64rem;
  font-weight: 600;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}

/* Mobile-first: hamburger toggle + fullscreen drawer */
.menu-toggle {
  position: relative;
  z-index: 102;
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  padding: 0.5rem 0.75rem;
  color: var(--paper);
  font: 600 0.75rem var(--font-sans);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(247, 244, 236, 0.15);
  border-radius: 2px;
  cursor: pointer;
}
.menu-toggle__icon,
.menu-toggle__icon::after {
  content: "";
  display: block;
  width: 1.1rem;
  height: 1px;
  background: currentColor;
  transition: transform 200ms var(--ease);
}
.menu-toggle__icon::after { transform: translateY(4px); }
.menu-toggle[aria-expanded="true"] .menu-toggle__icon {
  transform: rotate(45deg) translateY(0.5px);
}
.menu-toggle[aria-expanded="true"] .menu-toggle__icon::after {
  transform: rotate(-90deg) translateY(-1px) translateX(0.5px);
}

.primary-nav {
  position: fixed;
  z-index: 101;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  gap: 0;
  padding: 6.5rem 1.5rem 2.5rem;
  visibility: hidden;
  opacity: 0;
  background: var(--ink);
  transition: opacity 280ms var(--ease), visibility 280ms step-end;
}
.primary-nav.is-open {
  visibility: visible;
  opacity: 1;
  transition: opacity 280ms var(--ease), visibility 280ms step-start;
}
.primary-nav > a:not(.nav-cta) {
  position: relative;
  width: 100%;
  padding: 1.5rem 0;
  color: var(--paper);
  font-family: var(--font-display);
  font-size: clamp(2.2rem, 8vw, 3.2rem);
  border-bottom: 1px solid rgba(247, 244, 236, 0.08);
  transition: color 200ms var(--ease);
}
.primary-nav > a:not(.nav-cta):hover { color: var(--acid); }

.nav-cta {
  margin-top: auto;
  padding: 1.25rem;
  color: var(--ink);
  background: var(--acid);
  font-weight: 600;
  text-align: center;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  transition: background 200ms var(--ease), transform 200ms var(--ease);
}
.nav-cta:hover { background: var(--acid-bright); }

/* ---- 6. Section rail (desktop indicator) ----------------- */
.section-nav {
  position: fixed;
  z-index: 90;
  top: 50%;
  right: clamp(0.65rem, 1.35vw, 1.35rem);
  display: none;                 /* shown on large screens */
  grid-template-rows: 2.35rem auto 2.35rem;
  align-items: center;
  width: 2.7rem;
  padding: 0.2rem;
  color: var(--paper);
  border: 1px solid rgba(247, 244, 236, 0.16);
  background: rgba(17, 17, 15, 0.78);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  transform: translateY(-50%);
}
.section-nav__control {
  display: grid;
  place-items: center;
  width: 100%;
  height: 2.35rem;
  color: rgba(247, 244, 236, 0.78);
  font-size: 0.9rem;
  line-height: 1;
  transition: color 180ms var(--ease), background 180ms var(--ease);
}
.section-nav__control:hover,
.section-nav__control:focus-visible {
  color: var(--ink);
  background: var(--acid);
}
.section-nav__control[aria-disabled="true"] {
  pointer-events: none;
  color: rgba(247, 244, 236, 0.2);
}
.section-nav__count {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.08rem;
  padding: 0.7rem 0;
  color: rgba(247, 244, 236, 0.46);
  font-size: 0.52rem;
  font-weight: 600;
  line-height: 1;
  letter-spacing: 0.1em;
}
.section-nav__count [data-section-current] {
  color: var(--acid);
}

/* ---- 7. Hero --------------------------------------------- */
.hero {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 2.5rem;
  min-height: 100svh;
  padding: calc(var(--header-h) + 2.5rem) var(--gutter) 3rem;
  overflow: hidden;
  color: var(--paper);
  background:
    linear-gradient(rgba(255, 255, 255, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.025) 1px, transparent 1px),
    var(--ink);
  background-size: 4.5rem 4.5rem;
}

.hero__copy {
  z-index: 1;
  max-width: 52rem;
}
.hero .eyebrow {
  color: var(--acid);
}
.hero h1 {
  max-width: 15ch;
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(3rem, 11vw, 7.5rem);
  font-weight: 400;
  line-height: 0.94;
  letter-spacing: -0.045em;
}
.hero h1 em,
.engagements__header h2 em,
.closing h2 em {
  color: var(--copper);
  font-weight: 400;
}
.hero__intro {
  max-width: 37rem;
  margin: 1.9rem 0 0;
  color: rgba(247, 244, 236, 0.72);
  font-size: clamp(1rem, 1.3vw, 1.2rem);
}
.hero__actions {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 1.3rem;
  margin-top: 2.4rem;
}
.hero__actions .button {
  width: 100%;
  max-width: 24rem;
}

/* Hero diagram */
.hero__visual {
  position: relative;
  z-index: 1;
  display: none;               /* shown on desktop */
  min-height: 30rem;
  border: 1px solid var(--line-light);
  background: rgba(255, 255, 255, 0.018);
}
.diagram-kicker {
  position: absolute;
  top: 1.5rem;
  left: 1.5rem;
  margin: 0;
  color: rgba(247, 244, 236, 0.42);
  font-size: 0.66rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
}
.signal-map {
  position: absolute;
  inset: 5rem 2rem 6rem;
}
.signal-map::before,
.signal-map::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  border: 1px solid rgba(247, 244, 236, 0.08);
  border-radius: 50%;
  transform: translate(-50%, -50%);
}
.signal-map::before { width: 18rem; height: 18rem; }
.signal-map::after  { width: 11rem; height: 11rem; }

.signal-line {
  position: absolute;
  top: 50%;
  right: 8%;
  left: 8%;
  height: 1px;
  background: rgba(247, 244, 236, 0.28);
}
.signal-break {
  position: absolute;
  z-index: 3;
  top: calc(50% - 7px);
  left: 57%;
  width: 2.8rem;
  height: 15px;
  background: var(--ink);
}
.signal-break::before,
.signal-break::after {
  content: "";
  position: absolute;
  top: 7px;
  width: 14px;
  height: 1px;
  background: var(--acid);
}
.signal-break::before { left: 7px; transform: rotate(-55deg); }
.signal-break::after  { right: 7px; transform: rotate(-55deg); }

.signal-node {
  position: absolute;
  z-index: 2;
  top: calc(50% - 5px);
  width: 11px;
  height: 11px;
  background: var(--ink);
  border: 1px solid var(--paper);
  border-radius: 50%;
}
.signal-node--1 { left: 8%; }
.signal-node--2 { left: 33%; }
.signal-node--3 { left: 63%; border-color: var(--acid); }
.signal-node--4 { right: 8%; }

.signal-label {
  position: absolute;
  top: calc(50% + 1.5rem);
  color: rgba(247, 244, 236, 0.5);
  font-size: 0.67rem;
}
.signal-label--1 { left: 5%; }
.signal-label--2 { left: 27%; }
.signal-label--3 { left: 58%; color: var(--acid); }
.signal-label--4 { right: 4%; }

.signal-note {
  position: absolute;
  top: calc(50% - 3.3rem);
  left: 53%;
  color: var(--acid);
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-style: italic;
  transform: rotate(-7deg);
}

.visual-caption {
  position: absolute;
  right: 1.5rem;
  bottom: 1.5rem;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.2rem;
  text-align: right;
}
.visual-caption span {
  color: rgba(247, 244, 236, 0.4);
  font-size: 0.63rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
.visual-caption strong {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 400;
}

.hero__foot {
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 2rem;
  justify-content: space-between;
  color: rgba(247, 244, 236, 0.42);
  font-size: 0.66rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.hero__foot p { margin: 0; }

/* ---- 8. Section scaffold --------------------------------- */
.section {
  padding: clamp(4.5rem, 9vw, 8rem) var(--gutter);
}
.section-index {
  display: grid;
  grid-template-columns: 2.5rem 1fr;
  gap: 1rem;
  margin-bottom: clamp(2.5rem, 6vw, 4.5rem);
  padding-top: 0.9rem;
  color: var(--muted);
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  border-top: 1px solid var(--line-dark);
}
.section-index--light {
  color: rgba(247, 244, 236, 0.5);
  border-color: var(--line-light);
}

/* ---- 9. Thesis ------------------------------------------- */
.thesis {
  background: var(--paper);
}
.statement {
  max-width: 22ch;
  margin: 0 0 clamp(3rem, 7vw, 5rem);
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 8.5vw, 5rem);
  line-height: 1;
  letter-spacing: -0.035em;
  text-wrap: balance;
}
.statement em {
  color: var(--copper-dark);
  font-weight: 400;
}

.signal-list {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line-dark);
}
.signal-card {
  padding: 1.6rem 0 1.8rem;
  border-bottom: 1px solid var(--line-dark);
}
.signal-card:last-child { border-bottom: 0; }
.signal-card__number {
  color: var(--copper-dark);
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.12em;
}
.signal-card h2 {
  max-width: 14ch;
  margin: 1.4rem 0 0.9rem;
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 5vw, 2.5rem);
  font-weight: 400;
  line-height: 1;
}
.signal-card p {
  max-width: 34rem;
  margin: 0;
  color: var(--muted);
  font-size: clamp(0.94rem, 1.05vw, 1.02rem);
  line-height: 1.6;
}

/* ---- 10. Diagnostic / FRANK model ------------------------ */
.diagnostic {
  color: var(--paper);
  background: var(--ink-soft);
}
.diagnostic__intro {
  display: grid;
  gap: 1.4rem;
}
.diagnostic__intro h2 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(2.6rem, 8vw, 5.5rem);
  font-weight: 400;
  line-height: 0.98;
  letter-spacing: -0.04em;
  text-wrap: balance;
}
.diagnostic-bridge-text {
  max-width: 34rem;
  margin: 0;
  color: rgba(247, 244, 236, 0.75);
  font-size: clamp(1.02rem, 1.3vw, 1.2rem);
  line-height: 1.62;
}

.investigation {
  margin-top: clamp(2.75rem, 6vw, 4rem);
  border-top: 1px solid rgba(212, 178, 76, 0.6);
  border-bottom: 1px solid var(--line-light);
}
.investigation__steps {
  margin: 0;
  padding: 0;
  list-style: none;
}
.investigation__steps li {
  display: grid;
  grid-template-columns: 2.25rem 1fr;
  gap: 0.35rem 1rem;
  padding: 1.4rem 0;
  color: rgba(247, 244, 236, 0.72);
  border-bottom: 1px solid var(--line-light);
}
.investigation__steps li:last-child { border-bottom: 0; }
.investigation__steps li span {
  grid-row: span 2;
  color: var(--acid);
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  padding-top: 0.35rem;
}
.investigation__steps li strong {
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 4vw, 1.6rem);
  font-weight: 400;
  line-height: 1.05;
  color: rgba(247, 244, 236, 0.95);
}
.investigation__steps li small {
  color: rgba(247, 244, 236, 0.6);
  font-size: 0.9rem;
  line-height: 1.5;
}
.investigation__outcome {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  padding: 1.6rem 0 0.4rem;
}
.investigation__outcome p {
  margin: 0;
  color: var(--acid);
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}
.investigation__outcome strong {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 5vw, 2.4rem);
  font-weight: 400;
  line-height: 1.1;
}

/* ---- 11. Engagements ------------------------------------- */
.engagements {
  background: var(--bone);
}
.engagements__header {
  margin-bottom: clamp(2.5rem, 6vw, 4rem);
}
.engagements__header h2 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(3rem, 9vw, 6rem);
  font-weight: 400;
  line-height: 0.92;
  letter-spacing: -0.045em;
}

.engagement-grid {
  display: grid;
  gap: 0;
  border: 1px solid var(--line-dark);
  border-bottom: 0;
}
.engagement {
  position: relative;
  display: flex;
  flex-direction: column;
  min-height: 20rem;
  padding: 1.6rem;
  overflow: hidden;
  border-bottom: 1px solid var(--line-dark);
}
.engagement__topline {
  display: flex;
  justify-content: space-between;
  color: var(--muted);
  font-size: 0.64rem;
  font-weight: 600;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}
.engagement h3 {
  margin: 1.6rem 0 1rem;
  font-family: var(--font-display);
  font-size: clamp(2rem, 6vw, 2.85rem);
  font-weight: 400;
  line-height: 0.98;
}
.engagement p {
  max-width: 34rem;
  margin: 0 0 1.5rem;
  color: var(--muted);
  font-size: clamp(0.92rem, 1.05vw, 1rem);
  line-height: 1.6;
}
.engagement__detail {
  margin-top: auto;
  color: var(--copper-dark);
  font-size: 0.67rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}
.engagement a,
.engagement__action {
  display: flex;
  justify-content: space-between;
  margin-top: auto;
  padding-top: 1rem;
  font-size: 0.77rem;
  font-weight: 600;
  color: var(--copper-dark);
  border-top: 1px solid var(--line-dark);
  transition: color 180ms var(--ease);
}
.engagement a:hover,
.engagement__action:hover {
  color: var(--ink);
}

/* Feature card (Diagnostic Call) */
.engagement--feature {
  color: var(--paper);
  background: var(--copper-dark);
}
.engagement--feature .engagement__topline { color: rgba(247, 244, 236, 0.6); }
.engagement--feature p { color: rgba(247, 244, 236, 0.75); }
.engagement--feature a {
  color: var(--paper);
  border-top-color: rgba(247, 244, 236, 0.32);
}
.engagement--feature a:hover { color: var(--acid); }

/* Keynote card (abstract grid, dark) */
.engagement--abstract-grid {
  color: var(--paper);
  background: var(--ink);
  border-color: var(--ink);
}
.abstract-grid-overlay {
  position: absolute;
  inset: 0;
  z-index: 1;
  opacity: 0.14;
  background-image:
    linear-gradient(rgba(247, 244, 236, 0.1) 1px, transparent 1px),
    linear-gradient(90deg, rgba(247, 244, 236, 0.1) 1px, transparent 1px);
  background-size: 20px 20px;
  mask-image: radial-gradient(circle at 50% 50%, black, transparent 75%);
  -webkit-mask-image: radial-gradient(circle at 50% 50%, black, transparent 75%);
  pointer-events: none;
}
.engagement--abstract-grid::before {
  content: "";
  position: absolute;
  top: 55%;
  left: -10%;
  z-index: 1;
  width: 120%;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--acid), transparent);
  opacity: 0.45;
  transform: rotate(-15deg);
}
.engagement--abstract-grid::after {
  content: "";
  position: absolute;
  top: 55%;
  left: 60%;
  z-index: 2;
  width: 8px;
  height: 8px;
  background: var(--acid);
  border-radius: 50%;
  box-shadow: 0 0 12px var(--acid);
  transform: translate(-50%, -50%);
  animation: pulseNode 3s infinite alternate;
}
@keyframes pulseNode {
  0%   { transform: translate(-50%, -50%) scale(0.9); opacity: 0.6; }
  100% { transform: translate(-50%, -50%) scale(1.3); opacity: 1; }
}
.engagement--abstract-grid > *:not(.abstract-grid-overlay) {
  position: relative;
  z-index: 3;
}
.engagement--abstract-grid .engagement__topline { color: var(--acid); }
.engagement--abstract-grid p { color: rgba(247, 244, 236, 0.75); }
.engagement--abstract-grid .engagement__action {
  color: var(--paper);
  border-top-color: rgba(247, 244, 236, 0.22);
}
.engagement--abstract-grid .engagement__action:hover { color: var(--acid); }

/* ---- 11b. Case study (native details) -------------------- */
.case-study-trigger {
  margin-top: clamp(3rem, 6vw, 5rem);
  padding-top: clamp(2rem, 4vw, 3.5rem);
  border-top: 1px solid var(--line-dark);
}
.case-study-eyebrow {
  margin: 0 0 1.25rem;
  color: var(--copper-dark);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
}
.case-study-details {
  background: rgba(247, 244, 236, 0.4);
  border: 1px solid var(--line-dark);
  transition: background 280ms var(--ease);
}
.case-study-details[open] { background: var(--paper); }
.case-study-summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.6rem clamp(1.25rem, 3vw, 2.5rem);
  color: var(--ink);
  font-family: var(--font-display);
  font-size: clamp(1.3rem, 4vw, 2.1rem);
  font-style: italic;
  list-style: none;
  cursor: pointer;
  user-select: none;
}
.case-study-summary::-webkit-details-marker { display: none; }
.case-study-icon {
  flex-shrink: 0;
  font-family: var(--font-sans);
  font-size: 1.25rem;
  font-style: normal;
  transition: transform 280ms var(--ease);
}
.case-study-details[open] .case-study-icon { transform: rotate(180deg); }
.case-study-body {
  padding: 0 clamp(1.25rem, 3vw, 2.5rem) 2.5rem;
}
.case-study-meta {
  display: grid;
  gap: 1.25rem;
  margin-bottom: 2.25rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--line-dark);
}
.meta-item {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}
.meta-item span {
  color: var(--muted);
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}
.meta-item strong {
  color: var(--ink);
  font-family: var(--font-display);
  font-size: clamp(1rem, 1.35vw, 1.3rem);
  font-weight: 400;
  line-height: 1.25;
}
.case-study-text {
  display: grid;
  gap: 1.85rem;
}
.text-block h4 {
  margin: 0 0 0.8rem;
  color: var(--copper-dark);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
.text-block p {
  margin: 0;
  color: var(--muted);
  font-size: clamp(0.92rem, 1.05vw, 0.98rem);
  line-height: 1.62;
}

/* ---- 12. About ------------------------------------------- */
.about {
  position: relative;
  color: var(--paper);
  background: var(--ink-deep);
  overflow: hidden;
}
.about__portrait {
  position: relative;
  width: 100%;
  max-width: 30rem;
  aspect-ratio: 4 / 5;
  margin: 0 0 2.5rem;
  overflow: hidden;
  border: 1px solid rgba(247, 244, 236, 0.12);
  background: #17170f;
  isolation: isolate;
}
.about__portrait::before {
  content: "";
  position: absolute;
  z-index: 2;
  inset: 0;
  background: linear-gradient(180deg, rgba(13, 13, 11, 0.05) 45%, rgba(13, 13, 11, 0.72) 100%);
}
.about__portrait span {
  position: absolute;
  z-index: 3;
  bottom: -0.75rem;
  left: -0.75rem;
  font-family: var(--font-display);
  font-size: clamp(8rem, 26vw, 13rem);
  line-height: 0.7;
  letter-spacing: -0.1em;
  color: transparent;
  -webkit-text-stroke: 1px rgba(247, 244, 236, 0.16);
  pointer-events: none;
  user-select: none;
}
.about__portrait img {
  position: absolute;
  z-index: 1;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: 50% 18%;      /* focal point: face for this shot */
  filter: saturate(0.78) contrast(1.06) brightness(0.94);
}
.about__portrait.no-image img { display: none; }

.about__copy {
  position: relative;
  z-index: 1;
  max-width: 47rem;
}
.about__copy h2 {
  margin: 0 0 1.8rem;
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 7vw, 5rem);
  font-weight: 400;
  line-height: 1;
  letter-spacing: -0.035em;
  text-wrap: balance;
}
.about__lead {
  margin: 0 0 1.4rem;
  color: var(--paper);
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 4vw, 1.9rem);
  line-height: 1.25;
}
.about__copy > p:not(.eyebrow):not(.about__lead) {
  max-width: 41rem;
  margin: 0;
  color: rgba(247, 244, 236, 0.62);
  font-size: clamp(0.94rem, 1.05vw, 1.02rem);
  line-height: 1.62;
}

.experience {
  display: grid;
  gap: 0.75rem 2rem;
  margin-top: 2.75rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line-light);
}
.experience span {
  color: var(--acid);
  font-size: 0.64rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}
.experience strong {
  font-family: var(--font-display);
  font-size: clamp(1.05rem, 1.25vw, 1.25rem);
  font-weight: 400;
}

/* ---- 13. Closing ----------------------------------------- */
.closing {
  position: relative;
  text-align: center;
  background: var(--acid);
  overflow: hidden;
}
.closing::before,
.closing::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  aspect-ratio: 1;
  border-radius: 50%;
  transform: translate(-50%, -50%);
}
.closing::before {
  width: min(78vw, 46rem);
  border: 1px solid rgba(23, 23, 19, 0.16);
}
.closing::after {
  width: min(55vw, 31rem);
  border: 1px solid rgba(23, 23, 19, 0.12);
}
.closing > * {
  position: relative;
  z-index: 1;
}
.closing .eyebrow { color: var(--ink); }
.closing h2 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(3rem, 10vw, 7rem);
  font-weight: 400;
  line-height: 0.92;
  letter-spacing: -0.045em;
  text-wrap: balance;
}
.closing h2 em { color: var(--copper-dark); }
.closing__copy {
  max-width: 34rem;
  margin: 1.8rem auto;
  font-size: clamp(0.94rem, 1.05vw, 1.02rem);
  line-height: 1.6;
}
.closing .button {
  margin-top: 0.5rem;
  color: var(--paper);
  background: var(--ink);
}
.closing .button:hover { background: var(--ink-soft); }

/* ---- 14. Footer ------------------------------------------ */
.site-footer {
  display: grid;
  gap: 2.5rem;
  padding: 3.5rem var(--gutter);
  color: var(--paper);
  background: var(--ink);
}
.wordmark--footer { justify-self: start; }
.footer-brand p {
  margin: 1.25rem 0 0;
  color: rgba(247, 244, 236, 0.4);
  font-size: 0.66rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}
.footer-links {
  display: grid;
  border-top: 1px solid var(--line-light);
}
.footer-links a {
  display: flex;
  gap: 1rem;
  justify-content: space-between;
  padding: 0.95rem 0;
  color: rgba(247, 244, 236, 0.82);
  font-family: var(--font-display);
  font-size: 1.12rem;
  border-bottom: 1px solid var(--line-light);
  transition: color 180ms var(--ease);
}
.footer-links a:hover { color: var(--acid); }
.footer-links a > span:first-child {
  color: var(--acid);
  font: 600 0.58rem var(--font-sans);
  letter-spacing: 0.12em;
}
.footer-contact > span:last-child {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.1rem;
  margin-left: auto;
  color: rgba(247, 244, 236, 0.82);
  text-align: right;
}
.footer-contact strong { font-weight: 400; }
.footer-contact small {
  color: rgba(247, 244, 236, 0.5);
  font: 400 0.68rem var(--font-sans);
}
.footer-bottom {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  padding-top: 1.25rem;
  color: rgba(247, 244, 236, 0.4);
  font-size: 0.65rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border-top: 1px solid var(--line-light);
}

/* ============================================================
   RESPONSIVE — tablet
   ============================================================ */
@media (min-width: 680px) {
  .hero__actions {
    flex-direction: row;
    align-items: center;
    gap: 2rem;
  }
  .hero__actions .button { width: auto; }

  .signal-list {
    grid-template-columns: repeat(3, 1fr);
  }
  .signal-card {
    padding: 1.4rem clamp(1rem, 2vw, 2rem) 1.5rem 0;
    border-bottom: 0;
    border-right: 1px solid var(--line-dark);
  }
  .signal-card:not(:first-child) { padding-left: clamp(1rem, 2vw, 2rem); }
  .signal-card:last-child { border-right: 0; }

  .engagement-grid {
    grid-template-columns: repeat(2, 1fr);
    border-bottom: 1px solid var(--line-dark);
  }
  .engagement { border-right: 1px solid var(--line-dark); }
  .engagement:nth-child(2n) { border-right: 0; }

  .case-study-meta { grid-template-columns: repeat(3, 1fr); gap: 1.5rem; }
  .case-study-text { grid-template-columns: repeat(2, 1fr); gap: 2.5rem clamp(2.5rem, 5vw, 5rem); }

  .investigation__outcome {
    flex-direction: row;
    align-items: baseline;
    justify-content: space-between;
    gap: 1.5rem;
  }

  .experience {
    grid-template-columns: repeat(3, 1fr);
  }
  .experience span { grid-column: 1 / -1; margin-bottom: 0.2rem; }

  .footer-links { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-links a:nth-child(odd) { padding-right: 1.5rem; }
  .footer-links a:nth-child(even) {
    padding-left: 1.5rem;
    border-left: 1px solid var(--line-light);
  }
  .footer-bottom { flex-direction: row; justify-content: space-between; }
}

/* ============================================================
   RESPONSIVE — desktop (premium editorial layout)
   ============================================================ */
@media (min-width: 1000px) {
  :root {
    --header-h: 6.25rem;
    --scroll-offset: 6.5rem;
  }
  .site-header.is-scrolled { height: 5.25rem; }

  .section-nav { display: grid; }

  /* Nav: inline horizontal, hide the hamburger */
  .menu-toggle { display: none; }
  .primary-nav {
    position: static;
    inset: auto;
    flex-direction: row;
    align-items: center;
    gap: clamp(1.1rem, 2.3vw, 2.6rem);
    padding: 0;
    visibility: visible;
    opacity: 1;
    background: transparent;
    font-size: 0.82rem;
  }
  .primary-nav > a:not(.nav-cta) {
    width: auto;
    padding: 0;
    color: rgba(247, 244, 236, 0.72);
    font-family: var(--font-sans);
    font-size: 0.82rem;
    border-bottom: 0;
  }
  .primary-nav > a:not(.nav-cta)::after {
    content: "";
    position: absolute;
    right: 0;
    bottom: -0.45rem;
    left: 0;
    height: 1px;
    background: var(--paper);
    transform: scaleX(0);
    transform-origin: right;
    transition: transform 240ms var(--ease);
  }
  .primary-nav > a:not(.nav-cta):hover { color: var(--paper); }
  .primary-nav > a:not(.nav-cta):hover::after {
    transform: scaleX(1);
    transform-origin: left;
  }
  .nav-cta {
    margin-top: 0;
    padding: 0.72rem 1.05rem;
    text-align: left;
    letter-spacing: normal;
    text-transform: none;
  }
  .nav-cta:hover { transform: translateY(-2px); }

  /* Hero: two columns with dividing rule */
  .hero {
    display: grid;
    grid-template-columns: minmax(0, 1.1fr) minmax(24rem, 0.9fr);
    grid-template-rows: 1fr auto;
    gap: 0 clamp(2rem, 5vw, 6rem);
    align-items: center;
    padding: calc(var(--header-h) + 3.5rem) var(--gutter) 2.5rem;
  }
  .hero::before {
    content: "";
    position: absolute;
    top: var(--header-h);
    right: 38%;
    width: 1px;
    height: calc(100% - var(--header-h));
    background: var(--line-light);
  }
  .hero__copy { padding-right: clamp(2rem, 6vw, 7rem); }
  .hero__visual { display: block; align-self: center; }
  .hero__foot {
    grid-column: 1 / -1;
    padding-top: 2rem;
  }

  /* Thesis */
  .thesis {
    display: grid;
    grid-template-columns: minmax(10rem, 0.24fr) minmax(0, 0.76fr);
    gap: clamp(3rem, 6vw, 7rem);
  }
  .thesis .section-index { margin-bottom: 0; }
  .statement {
    max-width: 100%;
    font-size: clamp(2.8rem, 4vw, 4.6rem);
  }

  /* Diagnostic */
  .diagnostic__intro {
    grid-template-columns: minmax(0, 1.15fr) minmax(18rem, 0.85fr);
    gap: clamp(3rem, 6vw, 7rem);
    align-items: end;
  }
  .diagnostic__intro h2 { font-size: clamp(2.8rem, 3.8vw, 4.7rem); }

  .investigation__steps {
    display: grid;
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }
  .investigation__steps li {
    display: flex;
    flex-direction: column;
    gap: 0;
    min-height: 13rem;
    padding: 1.35rem;
    border-right: 1px solid var(--line-light);
    border-bottom: 0;
  }
  .investigation__steps li:last-child { border-right: 0; }
  .investigation__steps li span { padding-top: 0; }
  .investigation__steps li strong {
    display: flex;
    align-items: flex-end;
    min-height: 3.4rem;
    margin: 1.5rem 0 0.85rem;
    font-size: clamp(1.3rem, 1.55vw, 1.65rem);
  }
  .investigation__outcome {
    display: grid;
    grid-template-columns: 7.5rem 1fr;
    gap: 1.5rem;
    align-items: center;
    padding: 1.4rem 1.35rem;
    border-top: 1px solid var(--line-light);
  }
  .investigation__outcome strong { font-size: clamp(1.4rem, 1.7vw, 1.9rem); }

  /* Engagements: single premium row of four */
  .engagement-grid {
    grid-template-columns: 1.1fr repeat(3, minmax(0, 1fr));
  }
  .engagement {
    min-height: clamp(24rem, 34vh, 30rem);
    border-right: 1px solid var(--line-dark);
    border-bottom: 1px solid var(--line-dark);
  }
  .engagement:nth-child(2n) { border-right: 1px solid var(--line-dark); }
  .engagement:last-child { border-right: 0; }
  .engagement h3 {
    margin-top: auto;
    font-size: clamp(1.9rem, 2.3vw, 2.7rem);
  }

  /* About */
  .about {
    display: grid;
    grid-template-columns: minmax(18rem, 0.72fr) minmax(0, 1.28fr);
    gap: clamp(3rem, 7vw, 8rem);
    align-items: center;
  }
  .about .section-index { grid-column: 1 / -1; }
  .about__portrait {
    align-self: center;
    max-width: none;
    margin: 0;
    aspect-ratio: 4 / 5;
  }
  .about__copy h2 { font-size: clamp(2.8rem, 4vw, 4.6rem); }
  .about__lead { font-size: clamp(1.4rem, 1.8vw, 1.85rem); }
  .experience {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  /* Footer */
  .site-footer {
    grid-template-columns: minmax(14rem, 0.8fr) minmax(28rem, 1.2fr);
    gap: 2.5rem 6rem;
    align-items: start;
  }
  .footer-bottom { grid-column: 1 / -1; }
}

/* Extra breathing room on very wide screens */
@media (min-width: 1440px) {
  .section { padding-left: max(var(--gutter), calc((100vw - var(--max)) / 2)); padding-right: max(var(--gutter), calc((100vw - var(--max)) / 2)); }
  .hero,
  .site-header { padding-left: max(var(--gutter), calc((100vw - var(--max)) / 2)); padding-right: max(var(--gutter), calc((100vw - var(--max)) / 2)); }
}

/* ============================================================
   Motion & print
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
  .reveal { opacity: 1; transform: none; }
}

@media print {
  .skip-link,
  .menu-toggle,
  .primary-nav,
  .section-nav,
  .scroll-progress { display: none !important; }
  body { overflow: visible; -webkit-print-color-adjust: exact; print-color-adjust: exact; }
  .site-header { position: static; height: auto; padding: 1rem var(--gutter); }
  .reveal { opacity: 1; transform: none; }
  .hero { min-height: 0; }
}