:root {
  --cream: #fff8e6;
  --paper: #fffdf7;
  --ink: #333333;
  --muted: #7b756c;
  --teal: #5ba6a0;
  --coral: #f8afa6;
  --orange: #ff7800;
  --line: #e7dcc4;
  --font: "HK Grotesk", Arial, Helvetica, sans-serif;
}

@font-face {
  font-family: "HK Grotesk";
  src: url("https://cdn.glitch.me/605e2a51-d45f-4d87-a285-9410ad350515%2FHKGrotesk-Regular.otf?v=1603136326027") format("opentype");
  font-display: swap;
}

@font-face {
  font-family: "HK Grotesk";
  font-weight: 700;
  src: url("https://cdn.glitch.me/605e2a51-d45f-4d87-a285-9410ad350515%2FHKGrotesk-Bold.otf?v=1603136323437") format("opentype");
  font-display: swap;
}

* {
  box-sizing: border-box;
}

html {
  color: var(--ink);
  background: var(--cream);
  font-family: var(--font);
}

body {
  min-width: 320px;
  margin: 0;
  background: var(--cream);
  font-size: 17px;
  line-height: 1.5;
}

a {
  color: inherit;
  text-decoration-thickness: 1.5px;
  text-underline-offset: 0.18em;
}

a:hover {
  color: var(--teal);
}

a:focus-visible {
  outline: 3px solid var(--orange);
  outline-offset: 4px;
}

img {
  max-width: 100%;
}

/* Concept directory */

.study-index {
  min-height: 100vh;
}

.study-index-header,
.study-index-main {
  width: min(100% - 48px, 1120px);
  margin-inline: auto;
}

.study-index-header {
  display: flex;
  justify-content: space-between;
  padding-block: 28px;
  border-bottom: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.82rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.study-index-header a {
  color: var(--ink);
  font-weight: 700;
  text-decoration: none;
}

.study-index-main {
  padding-block: clamp(64px, 10vw, 128px) 96px;
}

.study-index-kicker {
  margin: 0 0 0.75rem;
  color: var(--teal);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.study-index h1 {
  max-width: 850px;
  margin: 0;
  color: var(--orange);
  font-size: clamp(4rem, 10vw, 8.75rem);
  letter-spacing: -0.075em;
  line-height: 0.82;
}

.study-index-intro {
  max-width: 610px;
  margin: 3rem 0 5rem 25%;
  font-size: 1.15rem;
}

.study-list {
  margin: 0;
  padding: 0;
  border-top: 3px solid var(--ink);
  list-style: none;
}

.study-list li {
  border-bottom: 1px solid var(--line);
}

.study-list a {
  display: grid;
  grid-template-columns: 56px minmax(190px, 0.8fr) minmax(280px, 1.4fr) 24px;
  gap: 1.25rem;
  align-items: baseline;
  padding: 1.55rem 0;
  text-decoration: none;
}

.study-list a:hover {
  color: var(--ink);
}

.study-list a:hover .study-name,
.study-list a:hover .study-arrow {
  color: var(--orange);
}

.study-number {
  color: var(--teal);
  font-size: 0.8rem;
  font-weight: 700;
}

.study-name {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.025em;
}

.study-description {
  color: var(--muted);
}

.study-arrow {
  color: var(--teal);
  font-size: 1.25rem;
  transition: transform 140ms ease;
}

.study-list a:hover .study-arrow {
  transform: translate(3px, -3px);
}

/* Shared concept frame */

.concept-page {
  --page-width: 1180px;
}

.concept-nav,
.concept-shell,
.concept-footer {
  width: min(100% - 48px, var(--page-width));
  margin-inline: auto;
}

.concept-nav {
  display: flex;
  gap: 2rem;
  justify-content: space-between;
  align-items: center;
  padding-block: 24px;
  border-bottom: 1px solid var(--line);
  font-size: 0.78rem;
}

.concept-nav-home {
  flex: 0 0 auto;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-decoration: none;
  text-transform: uppercase;
}

.concept-nav nav {
  display: flex;
  flex-wrap: wrap;
  gap: clamp(0.75rem, 2.5vw, 2rem);
  justify-content: flex-end;
}

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

.concept-nav nav a span:first-child {
  margin-right: 0.25rem;
  color: var(--teal);
  font-weight: 700;
}

.concept-nav nav a[aria-current="page"] {
  color: var(--ink);
  text-decoration: underline;
}

.concept-nav-label {
  display: none;
}

.concept-nav nav a[aria-current="page"] .concept-nav-label {
  display: inline;
}

.concept-shell {
  padding-block: clamp(64px, 9vw, 118px) 96px;
}

.concept-hero {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 1.25rem;
  align-items: start;
}

.concept-kicker {
  grid-column: 1 / -1;
  margin: 0 0 0.5rem;
  color: var(--teal);
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.11em;
  text-transform: uppercase;
}

.concept-title-block {
  grid-column: 1 / 10;
}

.concept-title-block h1 {
  margin: 0;
  color: var(--orange);
  font-size: clamp(4.5rem, 10vw, 8.5rem);
  letter-spacing: -0.078em;
  line-height: 0.8;
}

.concept-title-block h1 span {
  display: block;
}

.concept-portrait {
  grid-column: 10 / -1;
  grid-row: 2;
  width: min(100%, 230px);
  margin: 0 0 0 auto;
  overflow: hidden;
}

.concept-portrait img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.concept-bio {
  grid-column: 3 / 10;
  max-width: 710px;
  margin-top: 3.25rem;
  font-size: 1.05rem;
}

.concept-bio p {
  margin: 0 0 1.2rem;
}

.concept-sections {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(2rem, 5vw, 4.5rem);
  margin-top: clamp(72px, 11vw, 140px);
}

.concept-section {
  min-width: 0;
  border-top: 3px solid var(--line);
  padding-top: 1.1rem;
}

.concept-section-header {
  display: flex;
  gap: 0.75rem;
  align-items: baseline;
  margin-bottom: 1.35rem;
}

.concept-section-number {
  color: var(--teal);
  font-size: 0.7rem;
  font-weight: 700;
}

.concept-section h2 {
  margin: 0;
  color: var(--teal);
  font-size: 0.78rem;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.concept-links {
  margin: 0;
  padding: 0;
  list-style: none;
}

.concept-links li {
  border-bottom: 1px solid var(--line);
}

.concept-links a {
  display: flex;
  gap: 1rem;
  justify-content: space-between;
  align-items: baseline;
  padding-block: 0.65rem;
  font-weight: 700;
  line-height: 1.25;
  text-decoration: none;
}

.concept-links--compact a {
  font-weight: 400;
}

.concept-arrow {
  flex: 0 0 auto;
  color: var(--teal);
}

.concept-writing-list time {
  flex: 0 0 auto;
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 400;
  white-space: nowrap;
}

.concept-footer {
  display: flex;
  gap: 2rem;
  justify-content: space-between;
  padding-block: 24px 48px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.78rem;
}

.concept-footer p {
  max-width: 680px;
  margin: 0;
}

.concept-footer p span {
  color: var(--ink);
  font-weight: 700;
}

.concept-footer a {
  flex: 0 0 auto;
}

/* 01 — Margin Notes */

.theme-margin-notes .concept-title-block {
  position: relative;
}

.theme-margin-notes .concept-title-block::after {
  position: absolute;
  right: 2%;
  bottom: 0.18em;
  width: 23%;
  height: 0.08em;
  background: var(--coral);
  content: "";
}

.theme-margin-notes .concept-portrait {
  aspect-ratio: 1;
  border: 9px solid var(--coral);
  border-radius: 50%;
  transform: rotate(2deg);
}

.theme-margin-notes .concept-bio {
  padding-left: 1.2rem;
  border-left: 3px solid var(--teal);
}

.theme-margin-notes .concept-selected {
  grid-column: span 3;
}

/* 02 — Signal Blocks */

.theme-signal-blocks {
  --page-width: 1240px;
}

.theme-signal-blocks .concept-nav {
  border-bottom-color: var(--ink);
}

.theme-signal-blocks .concept-kicker {
  grid-column: 1 / 5;
  padding-top: 0.35rem;
  color: var(--ink);
}

.theme-signal-blocks .concept-title-block {
  grid-column: 1 / 9;
  padding: clamp(30px, 5vw, 64px);
  background: var(--orange);
}

.theme-signal-blocks .concept-title-block h1 {
  color: var(--cream);
  font-size: clamp(4.2rem, 9vw, 8rem);
}

.theme-signal-blocks .concept-portrait {
  grid-column: 9 / -1;
  width: min(100%, 255px);
  aspect-ratio: 1;
  margin: 2.5rem auto 0;
  border: 0;
  box-shadow: 18px 18px 0 var(--coral);
  transform: rotate(-2deg);
}

.theme-signal-blocks .concept-bio {
  display: grid;
  grid-column: 4 / -1;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(1.5rem, 4vw, 4rem);
  max-width: none;
  margin-top: 4.5rem;
}

.theme-signal-blocks .concept-bio p {
  margin: 0;
}

.theme-signal-blocks .concept-sections {
  gap: 0;
  border-top: 3px solid var(--ink);
  border-left: 1px solid var(--ink);
}

.theme-signal-blocks .concept-section {
  min-height: 290px;
  padding: 1.5rem;
  border-top: 0;
  border-right: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.theme-signal-blocks .concept-section-header {
  justify-content: space-between;
}

.theme-signal-blocks .concept-section-number,
.theme-signal-blocks .concept-section h2 {
  color: var(--orange);
}

/* 03 — Quiet Index */

.theme-quiet-index {
  --page-width: 900px;
  background: var(--paper);
}

.theme-quiet-index .concept-nav,
.theme-quiet-index .concept-shell,
.theme-quiet-index .concept-footer {
  width: min(100% - 64px, var(--page-width));
}

.theme-quiet-index .concept-shell {
  padding-top: clamp(88px, 13vw, 150px);
}

.theme-quiet-index .concept-kicker {
  grid-column: 1 / 7;
  color: var(--muted);
}

.theme-quiet-index .concept-title-block {
  grid-column: 1 / 10;
}

.theme-quiet-index .concept-title-block h1 {
  color: var(--ink);
  font-size: clamp(4.25rem, 9vw, 7rem);
  line-height: 0.86;
}

.theme-quiet-index .concept-title-block h1 span:last-child {
  color: var(--orange);
}

.theme-quiet-index .concept-portrait {
  grid-column: 10 / -1;
  width: 108px;
  aspect-ratio: 1;
  margin-top: 0.4rem;
  border: 5px solid var(--teal);
  border-radius: 50%;
}

.theme-quiet-index .concept-bio {
  grid-column: 2 / 11;
  max-width: 680px;
  margin-top: 5rem;
}

.theme-quiet-index .concept-bio p:first-child {
  font-size: 1.2rem;
  line-height: 1.45;
}

.theme-quiet-index .concept-sections {
  display: block;
}

.theme-quiet-index .concept-section {
  display: grid;
  grid-template-columns: minmax(150px, 0.65fr) minmax(0, 1.7fr);
  gap: 2rem;
  padding: 1.5rem 0 3.75rem;
  border-top: 1px solid var(--ink);
}

.theme-quiet-index .concept-section-header {
  justify-content: space-between;
  margin: 0;
}

.theme-quiet-index .concept-links li:last-child {
  border-bottom: 0;
}

.theme-quiet-index .concept-links a {
  padding-top: 0;
}

/* 04 — Split Profile */

.theme-split-profile {
  --page-width: 1260px;
  background: #f7f1df;
}

.theme-split-profile .concept-hero {
  grid-template-rows: auto auto auto;
  column-gap: clamp(2rem, 6vw, 6rem);
}

.theme-split-profile .concept-kicker {
  grid-column: 6 / -1;
  grid-row: 1;
}

.theme-split-profile .concept-title-block {
  grid-column: 6 / -1;
  grid-row: 2;
}

.theme-split-profile .concept-title-block h1 {
  font-size: clamp(4.25rem, 8vw, 7.5rem);
}

.theme-split-profile .concept-portrait {
  grid-column: 1 / 6;
  grid-row: 1 / 4;
  width: min(100%, 380px);
  aspect-ratio: 4 / 5;
  margin: 0;
  border: 12px solid var(--coral);
  border-radius: 0 0 46% 0;
  box-shadow: -18px 18px 0 var(--teal);
}

.theme-split-profile .concept-portrait img {
  object-position: 58% center;
}

.theme-split-profile .concept-bio {
  grid-column: 7 / -1;
  grid-row: 3;
  max-width: 620px;
  margin-top: 3.5rem;
}

.theme-split-profile .concept-sections {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin-left: calc(41.666% + 1.5rem);
}

.theme-split-profile .concept-writings {
  grid-column: 1 / -1;
}

/* 05 — Soft Geometry */

.theme-soft-geometry {
  --page-width: 1140px;
  background: #fff9ec;
}

.theme-soft-geometry .concept-shell {
  overflow: hidden;
}

.theme-soft-geometry .concept-hero {
  position: relative;
  padding: clamp(32px, 5vw, 64px);
  border: 2px solid var(--line);
  border-radius: 56px;
  background: var(--cream);
}

.theme-soft-geometry .concept-hero::before,
.theme-soft-geometry .concept-hero::after {
  position: absolute;
  z-index: 0;
  border-radius: 50%;
  content: "";
  pointer-events: none;
}

.theme-soft-geometry .concept-hero::before {
  top: -64px;
  right: -38px;
  width: 180px;
  aspect-ratio: 1;
  background: var(--coral);
  opacity: 0.55;
}

.theme-soft-geometry .concept-hero::after {
  bottom: -72px;
  left: 23%;
  width: 150px;
  aspect-ratio: 1;
  background: var(--teal);
  opacity: 0.22;
}

.theme-soft-geometry .concept-hero > * {
  position: relative;
  z-index: 1;
}

.theme-soft-geometry .concept-kicker {
  grid-column: 1 / 7;
}

.theme-soft-geometry .concept-title-block {
  grid-column: 1 / -1;
}

.theme-soft-geometry .concept-title-block h1 {
  font-size: clamp(4.25rem, 9vw, 8rem);
}

.theme-soft-geometry .concept-title-block h1 span:last-child {
  padding-left: 12%;
}

.theme-soft-geometry .concept-portrait {
  grid-column: 9 / -1;
  grid-row: 3;
  width: min(100%, 205px);
  aspect-ratio: 1;
  margin-top: 3rem;
  border: 9px solid var(--coral);
  border-radius: 48% 52% 46% 54% / 55% 43% 57% 45%;
  transform: rotate(3deg);
}

.theme-soft-geometry .concept-bio {
  display: grid;
  grid-column: 1 / 9;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 2.25rem;
  max-width: none;
  margin-top: 3rem;
}

.theme-soft-geometry .concept-sections {
  gap: 1.25rem;
  margin-top: 2rem;
}

.theme-soft-geometry .concept-section {
  padding: 1.5rem;
  border: 2px solid var(--line);
  border-radius: 28px;
  background: rgb(255 253 247 / 72%);
}

.theme-soft-geometry .concept-section:nth-child(2) {
  border-color: var(--coral);
}

.theme-soft-geometry .concept-section:nth-child(3) {
  border-color: var(--teal);
}

.theme-soft-geometry .concept-links li:last-child {
  border-bottom: 0;
}

/* 06 — Footnote */

.theme-footnote {
  --page-width: 980px;
  --muted: #767067;
  --teal: #397f7a;
  --orange: #e56500;
  background: var(--paper);
}

.theme-footnote .concept-shell {
  padding-top: clamp(88px, 10vw, 124px);
}

.theme-footnote .concept-kicker {
  grid-column: 1 / 4;
  color: var(--muted);
  letter-spacing: 0.13em;
  line-height: 1.55;
}

.theme-footnote .concept-title-block {
  grid-column: 3 / 11;
}

.theme-footnote .concept-title-block h1 {
  color: var(--ink);
  font-size: clamp(4.4rem, 7.4vw, 6.35rem);
  letter-spacing: -0.068em;
  line-height: 0.84;
}

.theme-footnote .concept-title-block h1 span:last-child {
  color: var(--orange);
}

.theme-footnote .concept-portrait {
  grid-column: 11 / -1;
  width: 92px;
  margin-top: 0.25rem;
  overflow: visible;
}

.theme-footnote .concept-portrait img {
  aspect-ratio: 1;
  border: 3px solid var(--teal);
  border-radius: 50%;
}

.theme-footnote .concept-bio {
  grid-column: 3 / 11;
  max-width: 650px;
  margin-top: 4.5rem;
  padding-left: 1.4rem;
  border-left: 1px solid var(--ink);
  font-size: 1.02rem;
  line-height: 1.55;
}

.theme-footnote .concept-bio p:first-child {
  font-size: 1.13rem;
  line-height: 1.5;
}

.theme-footnote .concept-bio em {
  text-decoration-color: var(--coral);
  text-decoration-line: underline;
  text-decoration-thickness: 0.32em;
  text-underline-offset: -0.16em;
  text-decoration-skip-ink: none;
}

.theme-footnote .concept-credentials {
  margin-top: 1.6rem;
  color: var(--muted);
  font-size: 0.78rem;
  letter-spacing: 0.015em;
}

.theme-footnote .concept-credentials span {
  margin-right: 0.35rem;
  color: var(--teal);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.theme-footnote .concept-sections {
  display: block;
  margin-top: clamp(88px, 9vw, 112px);
}

.theme-footnote .concept-section {
  display: grid;
  grid-template-columns: 170px minmax(0, 1fr);
  gap: 2.35rem;
  align-items: start;
  padding: 1.25rem 0 3.25rem;
  border-top: 1px solid var(--line);
}

.theme-footnote .concept-section-header {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 0.7rem;
  justify-content: normal;
  margin: 0;
}

.theme-footnote .concept-section-number {
  padding-top: 0.08rem;
}

.theme-footnote .concept-section h2 {
  line-height: 1.35;
}

.theme-footnote .concept-links li:last-child {
  border-bottom: 0;
}

.theme-footnote .concept-links a {
  min-height: 44px;
  padding-block: 0.72rem;
  transition: color 140ms ease;
}

.theme-footnote .concept-links li:first-child a {
  padding-top: 0.08rem;
}

.theme-footnote .concept-link-copy {
  display: grid;
  flex: 1 1 auto;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.12rem;
  align-items: start;
  min-width: 0;
}

.theme-footnote .concept-link-title {
  min-width: 0;
}

.theme-footnote .concept-link-meta {
  color: var(--muted);
  font-size: 0.76rem;
  font-weight: 400;
  letter-spacing: 0.02em;
  white-space: nowrap;
}

.theme-footnote .concept-arrow {
  transition: color 140ms ease, transform 140ms ease;
}

.theme-footnote .concept-links a:hover .concept-link-title {
  color: var(--orange);
}

.theme-footnote .concept-links a:hover .concept-arrow {
  color: var(--orange);
  transform: translate(2px, -2px);
}

.theme-footnote .concept-footer {
  justify-content: flex-start;
}

/* 07 — Side Index */

.theme-side-index {
  --page-width: 1100px;
  background: var(--paper);
}

.theme-side-index .concept-kicker {
  grid-column: 1 / 5;
  color: var(--muted);
}

.theme-side-index .concept-title-block {
  grid-column: 1 / 6;
}

.theme-side-index .concept-title-block h1 {
  color: var(--ink);
  font-size: clamp(4.3rem, 7.5vw, 6.5rem);
  line-height: 0.86;
}

.theme-side-index .concept-title-block h1 span:last-child {
  color: var(--orange);
}

.theme-side-index .concept-portrait {
  grid-column: 1 / 3;
  grid-row: 3;
  width: 88px;
  aspect-ratio: 1;
  margin: 3.5rem 0 0;
  border: 3px solid var(--teal);
}

.theme-side-index .concept-bio {
  display: grid;
  grid-column: 7 / -1;
  grid-row: 2 / 4;
  align-content: start;
  max-width: 510px;
  margin-top: 0;
  padding-top: 0.35rem;
  border-top: 1px solid var(--ink);
}

.theme-side-index .concept-bio p {
  margin-top: 1.25rem;
}

.theme-side-index .concept-sections {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin-left: calc(50% + 0.6rem);
}

.theme-side-index .concept-writings {
  grid-column: 1 / -1;
}

/* 08 — Open Ledger */

.theme-open-ledger {
  --page-width: 1080px;
  background: var(--paper);
}

.theme-open-ledger .concept-kicker {
  color: var(--muted);
}

.theme-open-ledger .concept-title-block {
  grid-column: 1 / -1;
  padding-block: 1.5rem 2rem;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.theme-open-ledger .concept-title-block h1 {
  color: var(--ink);
  font-size: clamp(4rem, 7.4vw, 6.4rem);
  line-height: 0.95;
}

.theme-open-ledger .concept-title-block h1 span {
  display: inline;
}

.theme-open-ledger .concept-title-block h1 span:last-child {
  color: var(--orange);
}

.theme-open-ledger .concept-portrait {
  grid-column: 1 / 3;
  grid-row: 3;
  width: 86px;
  aspect-ratio: 1;
  margin: 4rem 0 0;
  border: 3px solid var(--teal);
  border-radius: 50%;
}

.theme-open-ledger .concept-bio {
  display: grid;
  grid-column: 3 / -1;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 2.5rem;
  max-width: none;
  margin-top: 4rem;
}

.theme-open-ledger .concept-bio p {
  margin: 0;
}

.theme-open-ledger .concept-sections {
  display: block;
  border-top: 3px solid var(--ink);
}

.theme-open-ledger .concept-section {
  display: grid;
  grid-template-columns: minmax(180px, 0.8fr) minmax(0, 2fr);
  gap: 2rem;
  padding: 1.5rem 0 3.5rem;
  border-top: 0;
  border-bottom: 1px solid var(--line);
}

.theme-open-ledger .concept-section-header {
  justify-content: space-between;
  margin: 0;
}

/* 09 — Narrow Column */

.theme-narrow-column {
  --page-width: 760px;
  background: var(--paper);
}

.theme-narrow-column .concept-shell {
  padding-top: clamp(88px, 13vw, 150px);
}

.theme-narrow-column .concept-kicker {
  grid-column: 1 / 7;
  color: var(--muted);
}

.theme-narrow-column .concept-title-block {
  grid-column: 1 / 7;
}

.theme-narrow-column .concept-title-block h1 {
  color: var(--ink);
  font-size: clamp(3.9rem, 8vw, 5.8rem);
  line-height: 0.88;
}

.theme-narrow-column .concept-title-block h1 span:last-child {
  color: var(--orange);
}

.theme-narrow-column .concept-portrait {
  grid-column: 7 / -1;
  width: 76px;
  aspect-ratio: 1;
  margin-top: 0.25rem;
  border: 3px solid var(--teal);
  border-radius: 50%;
}

.theme-narrow-column .concept-bio {
  grid-column: 1 / 8;
  max-width: 620px;
  margin-top: 5.5rem;
}

.theme-narrow-column .concept-bio p:first-child {
  font-size: 1.16rem;
  line-height: 1.48;
}

.theme-narrow-column .concept-sections {
  display: block;
  max-width: 620px;
  margin-top: 7.5rem;
}

.theme-narrow-column .concept-section {
  padding: 1.15rem 0 3.75rem;
  border-top: 1px solid var(--ink);
}

.theme-narrow-column .concept-section-header {
  justify-content: space-between;
}

.theme-narrow-column .concept-links li:last-child {
  border-bottom: 0;
}

/* 10 — Centered Folio */

.theme-centered-folio {
  --page-width: 1040px;
  background: var(--paper);
}

.theme-centered-folio .concept-hero {
  text-align: center;
}

.theme-centered-folio .concept-kicker {
  grid-column: 1 / -1;
  color: var(--muted);
}

.theme-centered-folio .concept-title-block {
  grid-column: 2 / 12;
}

.theme-centered-folio .concept-title-block h1 {
  color: var(--ink);
  font-size: clamp(4.3rem, 8vw, 6.8rem);
  line-height: 0.87;
}

.theme-centered-folio .concept-title-block h1 span:last-child {
  color: var(--orange);
}

.theme-centered-folio .concept-portrait {
  grid-column: 6 / 8;
  grid-row: 3;
  width: 86px;
  aspect-ratio: 1;
  margin: 2.75rem auto 0;
  border: 3px solid var(--teal);
  border-radius: 50%;
}

.theme-centered-folio .concept-bio {
  display: grid;
  grid-column: 3 / 11;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 2.5rem;
  max-width: none;
  margin-top: 4rem;
  text-align: left;
}

.theme-centered-folio .concept-bio p {
  margin: 0;
}

.theme-centered-folio .concept-sections {
  gap: 2rem;
}

.theme-centered-folio .concept-section {
  border-top-width: 1px;
}

@media (max-width: 920px) {
  .concept-nav-label {
    display: none;
  }

  .concept-sections,
  .theme-signal-blocks .concept-sections {
    grid-template-columns: 1fr 1fr;
  }

  .concept-writings,
  .theme-signal-blocks .concept-writings {
    grid-column: 1 / -1;
  }

  .theme-split-profile .concept-sections {
    margin-left: 0;
  }

  .theme-side-index .concept-sections {
    margin-left: 0;
  }

  .theme-soft-geometry .concept-bio {
    grid-column: 1 / 10;
  }
}

@media (max-width: 700px) {
  body {
    font-size: 16px;
  }

  .study-index-header,
  .study-index-main,
  .concept-nav,
  .concept-shell,
  .concept-footer,
  .theme-quiet-index .concept-nav,
  .theme-quiet-index .concept-shell,
  .theme-quiet-index .concept-footer {
    width: min(100% - 32px, var(--page-width, 1120px));
  }

  .study-index-header {
    gap: 1rem;
    font-size: 0.72rem;
  }

  .study-index-main {
    padding-top: 56px;
  }

  .study-index h1 {
    font-size: clamp(3.5rem, 18vw, 5.7rem);
  }

  .study-index-intro {
    margin: 2.25rem 0 3.5rem;
  }

  .study-list a {
    grid-template-columns: 38px minmax(0, 1fr) 20px;
    gap: 0.7rem;
    padding-block: 1.2rem;
  }

  .study-name {
    font-size: 1.25rem;
  }

  .study-description {
    grid-column: 2 / -1;
    font-size: 0.9rem;
  }

  .study-arrow {
    grid-column: 3;
    grid-row: 1;
  }

  .concept-nav {
    display: block;
  }

  .concept-nav nav {
    justify-content: space-between;
    margin-top: 1rem;
    padding-top: 0.8rem;
    border-top: 1px solid var(--line);
  }

  .concept-nav nav a span:first-child {
    margin: 0;
  }

  .concept-shell {
    padding-block: 56px 72px;
  }

  .concept-hero,
  .theme-split-profile .concept-hero {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
  }

  .concept-kicker,
  .theme-signal-blocks .concept-kicker,
  .theme-split-profile .concept-kicker,
  .theme-soft-geometry .concept-kicker {
    order: 1;
    margin: 0;
  }

  .concept-title-block,
  .theme-signal-blocks .concept-title-block,
  .theme-split-profile .concept-title-block,
  .theme-soft-geometry .concept-title-block {
    order: 2;
    width: 100%;
  }

  .concept-title-block h1,
  .theme-signal-blocks .concept-title-block h1,
  .theme-quiet-index .concept-title-block h1,
  .theme-split-profile .concept-title-block h1,
  .theme-soft-geometry .concept-title-block h1 {
    font-size: clamp(3.2rem, 17vw, 5.4rem);
    line-height: 0.84;
  }

  .concept-portrait,
  .theme-signal-blocks .concept-portrait,
  .theme-quiet-index .concept-portrait,
  .theme-split-profile .concept-portrait,
  .theme-soft-geometry .concept-portrait {
    order: 3;
    width: 142px;
    aspect-ratio: 1;
    margin: 1rem 0 0;
  }

  .concept-bio,
  .theme-signal-blocks .concept-bio,
  .theme-quiet-index .concept-bio,
  .theme-split-profile .concept-bio,
  .theme-soft-geometry .concept-bio {
    display: block;
    order: 4;
    width: 100%;
    max-width: none;
    margin-top: 1.5rem;
  }

  .concept-sections,
  .theme-signal-blocks .concept-sections,
  .theme-split-profile .concept-sections,
  .theme-soft-geometry .concept-sections {
    display: block;
    margin-top: 64px;
    margin-left: 0;
    border-left: 0;
  }

  .concept-section,
  .theme-signal-blocks .concept-section,
  .theme-quiet-index .concept-section,
  .theme-soft-geometry .concept-section {
    display: block;
    min-height: 0;
    margin-top: 3rem;
    padding: 1rem 0 0;
    border: 0;
    border-top: 2px solid var(--line);
    border-radius: 0;
    background: transparent;
  }

  .concept-section-header,
  .theme-signal-blocks .concept-section-header,
  .theme-quiet-index .concept-section-header {
    justify-content: flex-start;
    margin-bottom: 1rem;
  }

  .concept-footer {
    display: block;
  }

  .concept-footer a {
    display: inline-block;
    margin-top: 0.8rem;
  }

  .theme-margin-notes .concept-title-block::after {
    display: none;
  }

  .theme-signal-blocks .concept-title-block {
    padding: 1.6rem;
  }

  .theme-signal-blocks .concept-title-block h1,
  .theme-soft-geometry .concept-title-block h1 {
    font-size: clamp(3rem, 15vw, 4.5rem);
  }

  .theme-footnote .concept-title-block h1,
  .theme-side-index .concept-title-block h1,
  .theme-open-ledger .concept-title-block h1,
  .theme-narrow-column .concept-title-block h1,
  .theme-centered-folio .concept-title-block h1 {
    font-size: clamp(3rem, 15vw, 4.5rem);
  }

  .theme-open-ledger .concept-title-block h1 span {
    display: block;
  }

  .theme-footnote .concept-portrait,
  .theme-side-index .concept-portrait,
  .theme-open-ledger .concept-portrait,
  .theme-narrow-column .concept-portrait,
  .theme-centered-folio .concept-portrait {
    margin: 1rem 0 0;
  }

  .theme-footnote .concept-bio,
  .theme-side-index .concept-bio,
  .theme-open-ledger .concept-bio,
  .theme-narrow-column .concept-bio,
  .theme-centered-folio .concept-bio {
    display: block;
    margin-top: 1.5rem;
    padding-top: 0;
  }

  .theme-footnote .concept-section-header {
    display: flex;
    gap: 0.75rem;
    justify-content: flex-start;
    margin-bottom: 1.15rem;
  }

  .theme-footnote .concept-link-copy {
    grid-template-columns: minmax(0, 1fr);
    gap: 0.12rem;
  }

  .theme-footnote .concept-link-meta {
    line-height: 1.35;
    white-space: normal;
  }

  .theme-footnote .concept-links li:first-child a {
    padding-top: 0.3rem;
  }

  .theme-footnote .concept-section,
  .theme-open-ledger .concept-section {
    display: block;
  }

  .theme-centered-folio .concept-hero {
    text-align: left;
  }

  .theme-signal-blocks .concept-portrait {
    margin-left: 12px;
    box-shadow: 12px 12px 0 var(--coral);
  }

  .theme-quiet-index .concept-shell {
    padding-top: 64px;
  }

  .theme-quiet-index .concept-bio p:first-child {
    font-size: 1.1rem;
  }

  .theme-split-profile .concept-portrait {
    border-width: 8px;
    box-shadow: -10px 10px 0 var(--teal);
  }

  .theme-soft-geometry .concept-hero {
    padding: 1.6rem;
    border-radius: 32px;
  }

  .theme-soft-geometry .concept-title-block h1 span:last-child {
    padding-left: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .study-arrow {
    transition: none;
  }
}