.page-about {
  --about-index-w: 220px;
  --about-hex-cut: 12px;
}

/* ---------- Hero ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  padding: 26px 0 clamp(36px, 6vw, 64px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: -70px 0 auto 0;
  height: 480px;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(58% 68% at 14% 0%, rgba(61, 123, 255, .20), transparent 70%),
    radial-gradient(48% 58% at 90% 10%, rgba(255, 90, 31, .13), transparent 72%);
}

.page-about .about-hero__kicker {
  margin: 0 0 14px;
  font-size: .74rem;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--c-gray);
}

.page-about .about-hero__title {
  margin: 0;
  max-width: 22ch;
}

.page-about .about-hero__lede {
  margin: clamp(16px, 2vw, 22px) 0 0;
  max-width: 66ch;
  color: var(--text-soft);
}

.page-about .about-hero__stats {
  list-style: none;
  margin: clamp(26px, 3.4vw, 42px) 0 0;
  padding: 22px 0 0;
  border-top: 1px solid var(--line-soft);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px 22px;
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 5px;
  min-width: 0;
}

.page-about .about-stat__num {
  font-size: clamp(1.55rem, 3vw, 2.1rem);
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--c-paper);
}

.page-about .about-stat__label {
  font-size: .8rem;
  letter-spacing: .05em;
  color: var(--text-muted);
}

/* ---------- Layout ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
}

.page-about .about-index {
  display: none;
}

.page-about .about-index__label {
  margin: 0 0 12px;
  font-size: .72rem;
  letter-spacing: .16em;
  color: var(--c-gray);
}

.page-about .about-index__list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-left: 1px solid var(--line-soft);
}

.page-about .about-index__list a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin-left: -1px;
  padding: 9px 12px;
  border-left: 2px solid transparent;
  font-size: .86rem;
  line-height: 1.45;
  color: var(--text-muted);
  text-decoration: none;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .about-index__list a .mono {
  font-size: .72rem;
  letter-spacing: .08em;
  color: var(--c-gray);
}

.page-about .about-index__list a:hover,
.page-about .about-index__list a:focus-visible {
  color: var(--text);
  border-left-color: var(--c-orange);
  background: rgba(27, 42, 58, .5);
}

.page-about .about-flow {
  min-width: 0;
}

/* progressive widening rhythm */
.page-about .about-flow > .about-sec { scroll-margin-top: 112px; }
.page-about .about-flow > .about-sec:nth-child(1) { margin-top: 0; }
.page-about .about-flow > .about-sec:nth-child(2) { margin-top: clamp(40px, 5vw, 72px); }
.page-about .about-flow > .about-sec:nth-child(3) { margin-top: clamp(48px, 6vw, 88px); }
.page-about .about-flow > .about-sec:nth-child(4) { margin-top: clamp(56px, 7vw, 104px); }
.page-about .about-flow > .about-sec:nth-child(5) { margin-top: clamp(64px, 8vw, 120px); }
.page-about .about-flow > .about-sec:nth-child(6) { margin-top: clamp(72px, 9vw, 136px); }
.page-about .about-flow > .about-sec:nth-child(7) { margin-top: clamp(80px, 10vw, 152px); }

.page-about .about-sec__head {
  margin-bottom: clamp(20px, 2.6vw, 32px);
}

.page-about .about-sec__lede {
  margin: 0 0 clamp(22px, 3vw, 34px);
  color: var(--text-soft);
  max-width: 68ch;
}

.page-about .about-note {
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 18px 0 18px 20px;
  border-left: 2px solid var(--c-paper);
  color: var(--text-soft);
}

/* ---------- 01 two columns ---------- */
.page-about .about-cols {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.page-about .about-col {
  padding: 22px 22px 24px;
  background: linear-gradient(158deg, rgba(27, 42, 58, .92), rgba(20, 24, 29, .58));
  border-left: 2px solid var(--c-orange);
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 14px, 100% 100%, 0 100%);
}

.page-about .about-col__title {
  margin: 0 0 10px;
  font-size: 1.06rem;
  letter-spacing: -.015em;
  color: var(--text);
}

.page-about .about-col p {
  margin: 0;
  font-size: .93rem;
  line-height: 1.78;
  color: var(--text-soft);
}

/* ---------- 02 team ---------- */
.page-about .about-team {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(22px, 3vw, 34px);
}

.page-about .about-team__text p {
  margin: 0 0 14px;
  max-width: 64ch;
  color: var(--text-soft);
  font-size: .95rem;
  line-height: 1.78;
}

.page-about .about-team__list {
  margin: 20px 0 0;
  display: grid;
  gap: 11px;
  font-size: .9rem;
  line-height: 1.7;
  color: var(--text-soft);
}

.page-about .about-team__list strong {
  color: var(--c-paper);
  font-weight: 600;
  margin-right: .45em;
}

.page-about .about-team__figure {
  margin: 0;
}

.page-about .about-figcap {
  display: block;
  margin: 10px 0 0;
  font-size: .76rem;
  letter-spacing: .04em;
  color: var(--text-muted);
}

/* ---------- 03 system ---------- */
.page-about .about-system {
  display: grid;
  gap: 16px;
}

.page-about .about-system__core {
  padding: 22px 22px 24px;
  border: 1px solid var(--line-soft);
  background: linear-gradient(140deg, rgba(61, 123, 255, .16), rgba(27, 42, 58, .55) 58%, rgba(10, 22, 38, .22));
  clip-path: polygon(0 0, calc(100% - 16px) 0, 100% 16px, 100% 100%, 0 100%);
}

.page-about .about-system__core-label {
  display: block;
  font-size: .74rem;
  letter-spacing: .16em;
  color: var(--c-orange);
}

.page-about .about-system__core-title {
  margin: 10px 0 8px;
  font-size: 1.16rem;
  font-weight: 700;
  letter-spacing: -.015em;
}

.page-about .about-system__core-text {
  margin: 0;
  max-width: 64ch;
  font-size: .92rem;
  line-height: 1.78;
  color: var(--text-soft);
}

.page-about .about-hexgrid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-about .about-hex {
  position: relative;
  padding: 18px 18px 20px;
  background: rgba(27, 42, 58, .52);
  border: 1px solid var(--line-soft);
  clip-path: polygon(0 0, calc(100% - var(--about-hex-cut)) 0, 100% var(--about-hex-cut), 100% 100%, var(--about-hex-cut) 100%, 0 calc(100% - var(--about-hex-cut)));
  transition: background-color var(--dur) var(--ease), border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .about-hex:hover,
.page-about .about-hex:focus-within {
  background: rgba(27, 42, 58, .88);
  border-color: rgba(255, 90, 31, .62);
  transform: translateY(-2px);
}

.page-about .about-hex__num {
  display: block;
  font-size: .72rem;
  letter-spacing: .14em;
  color: var(--c-orange);
}

.page-about .about-hex__title {
  margin: 7px 0 0;
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--text);
}

.page-about .about-hex__desc {
  margin: 9px 0 0;
  font-size: .86rem;
  line-height: 1.72;
  color: var(--text-soft);
}

.page-about .about-system__figure {
  margin-top: 6px;
}

/* ---------- 04 timeline ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 0 0 0 26px;
  position: relative;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 18px;
  bottom: 18px;
  width: 1px;
  background: linear-gradient(180deg, rgba(139, 149, 163, .48), rgba(139, 149, 163, .10));
}

.page-about .about-tl {
  position: relative;
}

.page-about .about-tl + .about-tl {
  margin-top: 10px;
}

.page-about .about-tl::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 19px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--c-space);
  border: 1.5px solid var(--c-gray);
  transition: background-color var(--dur) var(--ease), border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .about-tl:has(details[open])::before {
  background: var(--c-orange);
  border-color: var(--c-orange);
  box-shadow: 0 0 0 4px rgba(255, 90, 31, .16);
}

.page-about .about-tl__box {
  background: rgba(27, 42, 58, .44);
  border: 1px solid var(--line-soft);
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 0 100%);
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .about-tl__box[open] {
  background: rgba(27, 42, 58, .72);
  border-color: rgba(255, 90, 31, .45);
}

.page-about .about-tl__summary {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px 12px;
  padding: 14px 18px;
  cursor: pointer;
  list-style: none;
}

.page-about .about-tl__summary::-webkit-details-marker { display: none; }
.page-about .about-tl__summary::marker { content: ""; }

.page-about .about-tl__name {
  font-size: .96rem;
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--text);
}

.page-about .about-tl__cue {
  margin-left: auto;
  color: var(--c-gray);
}

.page-about .about-tl__cue::after {
  content: "＋";
  font-size: .95rem;
  line-height: 1;
}

.page-about .about-tl__box[open] .about-tl__cue::after {
  content: "－";
  color: var(--c-orange);
}

.page-about .about-tl__body {
  padding: 0 18px 18px;
}

.page-about .about-tl__body p {
  margin: 0;
  max-width: 68ch;
  font-size: .91rem;
  line-height: 1.78;
  color: var(--text-soft);
}

.page-about .about-versions__figure {
  margin-top: clamp(24px, 3.4vw, 40px);
}

/* ---------- 05 metrics ---------- */
.page-about .about-metrics {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}

.page-about .about-metric {
  background: rgba(27, 42, 58, .52);
  padding: 20px 20px 22px;
  min-width: 0;
}

.page-about .about-metric__num {
  display: block;
  font-size: clamp(1.6rem, 3.4vw, 2.3rem);
  line-height: 1.05;
  letter-spacing: -.02em;
  color: var(--c-lime);
}

.page-about .about-metric__label {
  display: block;
  margin-top: 9px;
  font-size: .86rem;
  color: var(--text);
}

.page-about .about-metric__note {
  display: block;
  margin-top: 5px;
  font-size: .78rem;
  line-height: 1.6;
  color: var(--text-muted);
}

/* ---------- 06 partners ---------- */
.page-about .about-partners {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about .about-partner {
  padding: 22px 22px 24px;
  background: rgba(20, 24, 29, .62);
  border: 1px solid var(--line-soft);
  clip-path: polygon(0 0, calc(100% - 16px) 0, 100% 16px, 100% 100%, 16px 100%, 0 calc(100% - 16px));
}

.page-about .about-partner__tag {
  display: block;
  font-size: .72rem;
  letter-spacing: .16em;
  color: var(--c-lime);
}

.page-about .about-partner__title {
  margin: 9px 0 10px;
  font-size: 1.06rem;
  letter-spacing: -.015em;
  color: var(--text);
}

.page-about .about-partner p {
  margin: 0;
  max-width: 60ch;
  font-size: .91rem;
  line-height: 1.78;
  color: var(--text-soft);
}

/* ---------- 07 cadence ---------- */
.page-about .about-cadence {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-cadence__row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 4px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-cadence__key {
  font-size: .78rem;
  letter-spacing: .14em;
  color: var(--c-paper);
}

.page-about .about-cadence__val {
  font-size: .92rem;
  line-height: 1.75;
  color: var(--text-soft);
  max-width: 66ch;
}

/* ---------- more ---------- */
.page-about .about-more {
  margin-top: clamp(56px, 8vw, 104px);
  padding-top: clamp(24px, 3vw, 36px);
  border-top: 1px solid var(--line-soft);
}

.page-about .about-more__label {
  margin: 0 0 18px;
  font-size: .72rem;
  letter-spacing: .16em;
  color: var(--c-gray);
}

.page-about .about-more__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-about .about-more__list a {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px 18px;
  text-decoration: none;
  background: rgba(27, 42, 58, .42);
  border: 1px solid var(--line-soft);
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 0 100%);
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .about-more__list a:hover,
.page-about .about-more__list a:focus-visible {
  border-color: rgba(255, 90, 31, .6);
  background: rgba(27, 42, 58, .78);
}

.page-about .about-more__t {
  font-size: .98rem;
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--text);
}

.page-about .about-more__d {
  font-size: .82rem;
  line-height: 1.65;
  color: var(--text-muted);
}

/* ---------- responsive ---------- */
@media (min-width: 640px) {
  .page-about .about-cols { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .page-about .about-hexgrid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .page-about .about-metrics { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .page-about .about-more__list { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .page-about .about-partners { gap: 16px; }
}

@media (min-width: 768px) {
  .page-about .about-hero__stats { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .page-about .about-cadence__row {
    grid-template-columns: 110px minmax(0, 1fr);
    gap: 18px;
    align-items: baseline;
    padding: 18px 0;
  }
  .page-about .about-partners { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 1024px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-index-w) minmax(0, 1fr);
    gap: clamp(36px, 4.5vw, 72px);
    align-items: start;
  }

  .page-about .about-index {
    display: block;
    position: sticky;
    top: 104px;
    align-self: start;
  }

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

  .page-about .about-hexgrid > li:nth-child(2),
  .page-about .about-hexgrid > li:nth-child(5) {
    transform: translateY(20px);
  }

  .page-about .about-hexgrid > li:nth-child(2):hover,
  .page-about .about-hexgrid > li:nth-child(5):hover {
    transform: translateY(17px);
  }
}

@media (min-width: 1200px) {
  .page-about { --about-index-w: 252px; }
  .page-about .about-team {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    align-items: start;
  }
  .page-about .about-metrics { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .page-about .about-more__list { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-hex,
  .page-about .about-hexgrid > li:nth-child(2),
  .page-about .about-hexgrid > li:nth-child(5) {
    transform: none !important;
    transition-duration: 1ms;
  }
}