.page-about {
  --pa-muted: var(--k5-steel);
  --pa-accent: var(--k5-cyan);
  --pa-rule-color: rgba(199, 209, 219, .18);
  background: var(--k5-carbon);
  color: var(--k5-paper);
  overflow-x: hidden;
}

.page-about img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ---------- Hero ---------- */
.page-about .pa-hero {
  position: relative;
  padding: calc(var(--k5-h-header) + 2rem) 0 clamp(2.2rem, 6vw, 3.6rem);
  background:
    radial-gradient(120% 90% at 88% 0%, var(--k5-violet-a), transparent 62%),
    radial-gradient(90% 70% at 8% 6%, var(--k5-cyan-a), transparent 66%),
    var(--k5-carbon);
  border-bottom: 1px solid var(--pa-rule-color);
}

.page-about .pa-hero__inner {
  display: grid;
  gap: 1.8rem;
}

.page-about .pa-crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .45rem;
  font-family: var(--k5-font-mono);
  font-size: .72rem;
  letter-spacing: .08em;
  color: var(--k5-steel);
  margin-bottom: 1.1rem;
}

.page-about .pa-crumbs a {
  color: var(--k5-steel);
  text-decoration: none;
}

.page-about .pa-crumbs a:hover {
  color: var(--k5-cyan);
}

.page-about .pa-crumbs [aria-current="page"] {
  color: var(--k5-yellow);
}

.page-about .pa-hero__kicker {
  margin: 0 0 .7rem;
  color: var(--k5-cyan);
}

.page-about .pa-hero__title {
  margin: 0;
  font-family: var(--k5-font-display);
  font-size: clamp(2.3rem, 10vw, 5rem);
  line-height: .98;
  letter-spacing: -.015em;
  font-weight: 900;
}

.page-about .pa-hero__title em {
  font-style: normal;
  color: var(--k5-cyan);
  text-shadow: 0 0 26px rgba(0, 229, 255, .42);
}

.page-about .pa-hero__lede {
  margin: 1.15rem 0 0;
  max-width: 47ch;
  font-size: clamp(.98rem, 2.6vw, 1.08rem);
  line-height: 1.85;
  color: var(--k5-steel);
}

.page-about .pa-stats {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 1.8rem 0 0;
  padding: 0;
  background: var(--pa-rule-color);
  border: 1px solid var(--pa-rule-color);
}

.page-about .pa-stats__item {
  display: flex;
  flex-direction: column;
  gap: .3rem;
  padding: .85rem .9rem;
  background: var(--k5-ink);
}

.page-about .pa-stats__num {
  font-family: var(--k5-font-mono);
  font-size: clamp(1.15rem, 4vw, 1.5rem);
  font-weight: 700;
  color: var(--k5-cyan);
  letter-spacing: -.01em;
}

.page-about .pa-stats__label {
  font-size: .74rem;
  line-height: 1.5;
  color: var(--k5-steel);
}

.page-about .pa-hero__figure {
  margin: 0;
  position: relative;
  border: 1px solid var(--pa-rule-color);
  background: var(--k5-ink);
}

.page-about .pa-hero__figure img {
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  filter: saturate(1.05) contrast(1.05);
}

.page-about .pa-hero__cap {
  position: absolute;
  left: 0;
  bottom: 0;
  max-width: 100%;
  padding: .4rem .7rem;
  font-family: var(--k5-font-mono);
  font-size: .68rem;
  letter-spacing: .04em;
  color: var(--k5-carbon);
  background: var(--k5-yellow);
}

.page-about .pa-index {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--pa-rule-color);
  border-top: 1px solid var(--pa-rule-color);
  padding-top: 1px;
}

.page-about .pa-index__item {
  display: flex;
  align-items: baseline;
  gap: .5rem;
  padding: .8rem .6rem .8rem 0;
  font-size: .82rem;
  color: var(--k5-steel);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--k5-dur) var(--k5-ease), border-color var(--k5-dur) var(--k5-ease);
}

.page-about .pa-index__item:hover,
.page-about .pa-index__item:focus-visible {
  color: var(--k5-paper);
  border-bottom-color: var(--k5-cyan);
}

.page-about .pa-index__no {
  font-family: var(--k5-font-mono);
  font-size: .7rem;
  color: var(--k5-cyan);
}

/* ---------- Chapter shell ---------- */
.page-about .pa-chapter {
  position: relative;
  padding: clamp(2.6rem, 7vw, 5rem) 0;
  border-top: 1px solid transparent;
}

.page-about .pa-chapter--paper {
  --pa-muted: #4E5965;
  --pa-accent: var(--k5-cyan-deep);
  --pa-rule-color: rgba(11, 13, 16, .16);
  background: var(--k5-paper);
  color: var(--k5-carbon);
}

.page-about .pa-chapter--ink {
  background:
    linear-gradient(180deg, rgba(124, 77, 255, .08), transparent 40%),
    var(--k5-ink);
  border-top: 1px solid var(--pa-rule-color);
  border-bottom: 1px solid var(--pa-rule-color);
}

.page-about .pa-chapter__grid {
  display: grid;
  gap: 1.6rem;
}

.page-about .pa-chapter__aside {
  border-left: 3px solid var(--pa-accent);
  padding-left: 1rem;
}

.page-about .pa-chapter__no {
  margin: 0;
  font-family: var(--k5-font-mono);
  font-size: .78rem;
  letter-spacing: .24em;
  color: var(--pa-accent);
}

.page-about .pa-chapter__kicker {
  margin: .35rem 0 0;
  font-family: var(--k5-font-mono);
  font-size: .72rem;
  letter-spacing: .16em;
  color: var(--pa-muted);
}

.page-about .pa-chapter__title {
  margin: .55rem 0 0;
  font-family: var(--k5-font-editorial);
  font-size: clamp(1.55rem, 5vw, 2.35rem);
  line-height: 1.2;
  font-weight: 700;
}

.page-about .pa-chapter__note {
  margin: .6rem 0 0;
  font-size: .8rem;
  line-height: 1.6;
  color: var(--pa-muted);
}

.page-about .pa-chapter__body > * + * {
  margin-top: 1.4rem;
}

/* ---------- Chapter 01 ---------- */
.page-about .pa-quote {
  margin: 0;
  padding-left: 1rem;
  border-left: 3px solid var(--pa-accent);
  font-family: var(--k5-font-editorial);
  font-size: clamp(1.15rem, 3.4vw, 1.62rem);
  line-height: 1.6;
  font-weight: 600;
}

.page-about .pa-copy {
  margin: 0;
  font-size: clamp(.95rem, 2.6vw, 1.05rem);
  line-height: 1.9;
  color: var(--pa-muted);
}

.page-about .pa-values {
  display: grid;
  gap: 1.1rem;
}

.page-about .pa-values__item {
  border-top: 2px solid var(--pa-accent);
  padding-top: .75rem;
}

.page-about .pa-values__no {
  margin: 0;
  font-family: var(--k5-font-mono);
  font-size: .72rem;
  letter-spacing: .2em;
  color: var(--pa-accent);
}

.page-about .pa-values__title {
  margin: .3rem 0 .4rem;
  font-family: var(--k5-font-editorial);
  font-size: 1.15rem;
  font-weight: 700;
}

.page-about .pa-values__text {
  margin: 0;
  font-size: .9rem;
  line-height: 1.8;
  color: var(--pa-muted);
}

/* ---------- Tabs ---------- */
.page-about .pa-tabs__list {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem;
  margin: 0 0 1.4rem;
}

.page-about .pa-tabs__btn {
  font-family: var(--k5-font-mono);
  font-size: .78rem;
  letter-spacing: .05em;
  padding: .55rem .85rem;
  background: transparent;
  color: var(--k5-steel);
  border: 1px solid var(--pa-rule-color);
  border-radius: var(--k5-radius);
  cursor: pointer;
  transition: color var(--k5-dur) var(--k5-ease),
    border-color var(--k5-dur) var(--k5-ease),
    background var(--k5-dur) var(--k5-ease);
}

.page-about .pa-tabs__btn:hover {
  color: var(--k5-paper);
  border-color: var(--k5-cyan);
}

.page-about .pa-tabs__btn[aria-selected="true"] {
  background: var(--k5-cyan);
  border-color: var(--k5-cyan);
  color: var(--k5-carbon);
  font-weight: 700;
}

.page-about .pa-tabs__btn:focus-visible {
  outline: 2px solid var(--k5-yellow);
  outline-offset: 2px;
}

.page-about .pa-tabs__panel {
  border-top: 1px solid var(--pa-rule-color);
  padding-top: 1.3rem;
}

.page-about .pa-tabs__panel[hidden] {
  display: none;
}

.page-about .pa-panel__grid {
  display: grid;
  gap: 1.3rem;
}

.page-about .pa-panel__title {
  margin: 0 0 .6rem;
  font-family: var(--k5-font-editorial);
  font-size: clamp(1.1rem, 3.4vw, 1.35rem);
  line-height: 1.4;
}

.page-about .pa-panel__text {
  margin: 0 0 .75rem;
  font-size: .93rem;
  line-height: 1.85;
  color: var(--k5-steel);
}

.page-about .pa-panel__link {
  margin: .9rem 0 0;
  font-family: var(--k5-font-mono);
  font-size: .8rem;
}

.page-about .pa-panel__link a,
.page-about .pa-collab__link a {
  color: var(--k5-cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(0, 229, 255, .45);
  padding-bottom: .15rem;
}

.page-about .pa-panel__link a:hover,
.page-about .pa-collab__link a:hover {
  color: var(--k5-yellow);
  border-bottom-color: var(--k5-yellow);
}

.page-about .pa-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: .55rem;
  align-content: start;
}

.page-about .pa-list li {
  position: relative;
  padding-left: 1.25rem;
  font-size: .88rem;
  line-height: 1.75;
  color: var(--pa-muted);
}

.page-about .pa-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .85em;
  width: .6rem;
  height: 2px;
  background: var(--pa-accent);
}

/* ---------- Media band ---------- */
.page-about .pa-band {
  margin: 1.6rem 0 0;
  border: 1px solid var(--pa-rule-color);
}

.page-about .pa-band img {
  width: 100%;
  aspect-ratio: 10 / 7;
  object-fit: cover;
}

.page-about .pa-band--wide img {
  aspect-ratio: 5 / 3;
}

.page-about .pa-band__cap {
  padding: .55rem .8rem;
  font-family: var(--k5-font-mono);
  font-size: .68rem;
  line-height: 1.6;
  letter-spacing: .03em;
  color: var(--pa-muted);
  border-top: 1px solid var(--pa-rule-color);
}

/* ---------- Timeline ---------- */
.page-about .pa-timeline {
  list-style: none;
  margin: 0;
  padding: 0 0 0 .2rem;
}

.page-about .pa-timeline__item {
  position: relative;
  padding: 0 0 1.5rem 1.5rem;
  border-left: 1px solid var(--pa-rule-color);
}

.page-about .pa-timeline__item:last-child {
  border-left-color: transparent;
  padding-bottom: 0;
}

.page-about .pa-timeline__item::before {
  content: "";
  position: absolute;
  left: -5px;
  top: .4rem;
  width: 9px;
  height: 9px;
  background: var(--pa-accent);
  box-shadow: 0 0 12px rgba(0, 124, 138, .5);
}

.page-about .pa-timeline__phase {
  margin: 0;
  font-family: var(--k5-font-mono);
  font-size: .7rem;
  letter-spacing: .18em;
  color: var(--pa-accent);
}

.page-about .pa-timeline__title {
  margin: .25rem 0 .35rem;
  font-family: var(--k5-font-editorial);
  font-size: 1.1rem;
  font-weight: 700;
}

.page-about .pa-timeline__text {
  margin: 0;
  font-size: .9rem;
  line-height: 1.85;
  color: var(--pa-muted);
}

/* ---------- Principles ---------- */
.page-about .pa-principles {
  display: grid;
  gap: 1rem;
}

.page-about .pa-principles__card {
  position: relative;
  padding: 1.2rem 1.1rem;
  background: var(--k5-carbon);
  border: 1px solid var(--pa-rule-color);
}

.page-about .pa-principles__card::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 34px;
  height: 34px;
  background: linear-gradient(225deg, var(--k5-violet-a), transparent 70%);
}

.page-about .pa-principles__no {
  margin: 0;
  font-family: var(--k5-font-mono);
  font-size: .82rem;
  letter-spacing: .2em;
  color: var(--k5-yellow);
}

.page-about .pa-principles__title {
  margin: .5rem 0 .6rem;
  font-family: var(--k5-font-editorial);
  font-size: clamp(1.05rem, 3.2vw, 1.25rem);
  line-height: 1.45;
}

.page-about .pa-principles__text {
  margin: 0;
  font-size: .9rem;
  line-height: 1.85;
  color: var(--k5-steel);
}

.page-about .pa-principles__card--wide .pa-list {
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px dashed var(--pa-rule-color);
}

/* ---------- Collaboration ---------- */
.page-about .pa-collab {
  display: grid;
  gap: 1rem;
}

.page-about .pa-collab__item {
  padding: 1.15rem 1.05rem;
  background: var(--k5-paper);
  border: 1px solid var(--pa-rule-color);
  border-top: 3px solid var(--k5-violet);
}

.page-about .pa-collab__item--wide {
  border-top-color: var(--k5-cyan-deep);
}

.page-about .pa-collab__tag {
  display: inline-block;
  margin: 0 0 .6rem;
  padding: .18rem .45rem;
  font-family: var(--k5-font-mono);
  font-size: .66rem;
  letter-spacing: .12em;
  color: var(--k5-carbon);
  background: var(--k5-yellow);
}

.page-about .pa-collab__title {
  margin: 0 0 .45rem;
  font-family: var(--k5-font-editorial);
  font-size: clamp(1.08rem, 3.4vw, 1.3rem);
  font-weight: 700;
}

.page-about .pa-collab__text {
  margin: 0;
  font-size: .9rem;
  line-height: 1.85;
  color: #4E5965;
}

.page-about .pa-collab__link {
  margin: .9rem 0 0;
  font-family: var(--k5-font-mono);
  font-size: .8rem;
}

.page-about .pa-collab__link a {
  color: #007C8A;
  border-bottom-color: rgba(0, 124, 138, .45);
}

.page-about .pa-fold {
  margin-top: .85rem;
  border-top: 1px dashed var(--pa-rule-color);
}

.page-about .pa-fold .k5-fold__head {
  padding: .6rem 0;
  font-family: var(--k5-font-mono);
  font-size: .78rem;
  letter-spacing: .04em;
  color: var(--k5-cyan-deep);
  cursor: pointer;
}

.page-about .pa-fold .k5-fold__body p {
  margin: 0 0 .6rem;
  font-size: .86rem;
  line-height: 1.85;
  color: #4E5965;
}

/* ---------- Start / CTA ---------- */
.page-about .pa-start {
  padding: clamp(2.4rem, 6vw, 4rem) 0;
  background:
    linear-gradient(120deg, var(--k5-violet-a), transparent 55%),
    var(--k5-carbon);
  border-top: 1px solid var(--pa-rule-color);
}

.page-about .pa-start__inner {
  display: grid;
  gap: 1.6rem;
}

.page-about .pa-start__title {
  margin: .5rem 0 .7rem;
  font-family: var(--k5-font-display);
  font-size: clamp(1.7rem, 6vw, 2.6rem);
  line-height: 1.1;
  letter-spacing: -.01em;
}

.page-about .pa-start__text {
  margin: 0;
  max-width: 52ch;
  font-size: .94rem;
  line-height: 1.9;
  color: var(--k5-steel);
}

.page-about .pa-start__links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--pa-rule-color);
  border: 1px solid var(--pa-rule-color);
}

.page-about .pa-start__link {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: .55rem;
  padding: .85rem .9rem;
  background: var(--k5-ink);
  color: var(--k5-paper);
  text-decoration: none;
  font-size: .92rem;
  transition: background var(--k5-dur) var(--k5-ease), color var(--k5-dur) var(--k5-ease);
}

.page-about .pa-start__link:hover,
.page-about .pa-start__link:focus-visible {
  background: var(--k5-cyan);
  color: var(--k5-carbon);
}

.page-about .pa-start__link-no {
  font-family: var(--k5-font-mono);
  font-size: .72rem;
  color: var(--k5-cyan);
}

.page-about .pa-start__link:hover .pa-start__link-no,
.page-about .pa-start__link:focus-visible .pa-start__link-no {
  color: var(--k5-carbon);
}

.page-about .pa-start__link-note {
  font-family: var(--k5-font-mono);
  font-size: .7rem;
  color: var(--k5-steel);
}

.page-about .pa-start__link:hover .pa-start__link-note,
.page-about .pa-start__link:focus-visible .pa-start__link-note {
  color: rgba(11, 13, 16, .72);
}

/* ---------- Responsive ---------- */
@media (min-width: 640px) {
  .page-about .pa-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .pa-index {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .pa-values {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.3rem;
  }

  .page-about .pa-panel__grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr);
    gap: 1.6rem;
  }

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

@media (min-width: 900px) {
  .page-about .pa-hero__inner {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    column-gap: clamp(2rem, 4vw, 3.4rem);
    align-items: end;
  }

  .page-about .pa-index {
    grid-column: 1 / -1;
    grid-template-columns: repeat(5, minmax(0, 1fr));
    margin-top: .4rem;
  }

  .page-about .pa-chapter__grid {
    grid-template-columns: minmax(0, 3.2fr) minmax(0, 8.8fr);
    column-gap: clamp(2rem, 4.5vw, 4rem);
  }

  .page-about .pa-chapter__aside {
    position: sticky;
    top: calc(var(--k5-h-header) + 2rem);
    align-self: start;
  }

  .page-about .pa-principles {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 1.1rem;
  }

  .page-about .pa-principles__card:nth-child(1) {
    grid-column: span 7;
  }

  .page-about .pa-principles__card:nth-child(2) {
    grid-column: span 5;
  }

  .page-about .pa-principles__card:nth-child(3) {
    grid-column: span 12;
  }

  .page-about .pa-collab {
    grid-template-columns: repeat(6, minmax(0, 1fr));
    gap: 1.1rem;
  }

  .page-about .pa-collab__item:nth-child(1) {
    grid-column: span 4;
  }

  .page-about .pa-collab__item:nth-child(2) {
    grid-column: span 2;
  }

  .page-about .pa-collab__item:nth-child(3) {
    grid-column: span 6;
  }

  .page-about .pa-start__inner {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    column-gap: clamp(2rem, 5vw, 4rem);
    align-items: start;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .pa-index__item,
  .page-about .pa-tabs__btn,
  .page-about .pa-start__link {
    transition: none;
  }
}
<<<END>>>