.page-about {
  --about-gutter: 22px;
  --about-rail: 150px;
}

.page-about .label {
  letter-spacing: .18em;
  color: var(--cyan);
}

.page-about .label--ink {
  color: var(--ink-700);
}

/* ---------- hero ---------- */
.page-about .hero {
  padding-top: clamp(20px, 4vw, 36px);
}

.page-about .breadcrumb {
  margin-bottom: clamp(22px, 4vw, 40px);
}

.page-about .hero-grid {
  display: grid;
  gap: clamp(26px, 4vw, 44px);
  align-items: end;
}

.page-about .hero-copy h1 {
  margin: 14px 0 0;
  font-size: clamp(30px, 7vw, 56px);
  line-height: 1.08;
  letter-spacing: -.02em;
  font-weight: 900;
  color: var(--text);
  max-width: 15em;
}

.page-about .hero-lead {
  margin: 18px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--slate);
  max-width: 36em;
}

.page-about .hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

.page-about .hero-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px 18px;
  margin: 30px 0 0;
  padding: 20px 0 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.page-about .hero-stats li {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .stat-num {
  font-family: var(--font-mono);
  font-size: clamp(26px, 5vw, 34px);
  font-weight: 600;
  line-height: 1.05;
  color: var(--cyan);
  letter-spacing: -.02em;
}

.page-about .stat-num .unit {
  font-size: .55em;
  margin-left: 2px;
  color: var(--mist);
}

.page-about .stat-cap {
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--slate);
}

.page-about .hero-figure {
  position: relative;
  margin: 0;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-l);
  overflow: hidden;
  background:
    radial-gradient(120% 100% at 80% 0%, rgba(61, 231, 255, .14), transparent 60%),
    var(--ink-800);
}

.page-about .hero-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .fig-cap {
  position: absolute;
  left: 14px;
  bottom: 12px;
  padding: 5px 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--mist);
  background: rgba(6, 20, 38, .72);
  border: 1px solid var(--line);
  border-radius: 999px;
}

/* ---------- origin ---------- */
.page-about .origin-card {
  padding: clamp(22px, 4vw, 44px);
  border-radius: var(--radius-l);
  background: var(--paper);
  color: var(--ink-text);
  position: relative;
  overflow: hidden;
}

.page-about .origin-card::after {
  content: "";
  position: absolute;
  inset: auto -40px -60px auto;
  width: 220px;
  height: 220px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255, 139, 61, .22), transparent 68%);
  pointer-events: none;
}

.page-about .origin-head h2 {
  margin: 10px 0 0;
  font-size: clamp(24px, 4.4vw, 36px);
  line-height: 1.2;
  letter-spacing: -.01em;
  font-weight: 800;
  color: var(--ink-text);
}

.page-about .origin-body {
  margin-top: 20px;
  display: grid;
  gap: 18px;
}

.page-about .origin-body > p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: #17304e;
  max-width: 44em;
}

.page-about .origin-line {
  display: grid;
  gap: 0;
  margin: 8px 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--paper-line);
}

.page-about .origin-line li {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr);
  gap: 4px 12px;
  padding: 16px 0;
  border-bottom: 1px solid var(--paper-line);
}

.page-about .line-idx {
  grid-row: span 2;
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 600;
  color: var(--amber);
  align-self: start;
}

.page-about .origin-line strong {
  font-size: 16px;
  color: var(--ink-text);
}

.page-about .origin-line p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: #3a5069;
}

/* ---------- timeline ---------- */
.page-about .timeline-head {
  max-width: 42em;
}

.page-about .timeline-head h2 {
  margin: 0;
  font-size: clamp(24px, 4.6vw, 36px);
  line-height: 1.2;
  letter-spacing: -.015em;
  font-weight: 800;
  color: var(--text);
}

.page-about .timeline-head p {
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--slate);
}

.page-about .era-grid {
  display: grid;
  gap: 26px;
  margin-top: clamp(26px, 4vw, 44px);
}

.page-about .era-rail {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 10px;
}

.page-about .rail-label {
  width: 100%;
  margin: 0 0 2px;
  font-size: 11px;
}

.page-about .era-list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}

.page-about .era-list::-webkit-scrollbar {
  display: none;
}

.page-about .era-list a {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 7px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  text-decoration: none;
  white-space: nowrap;
  transition: border-color .25s var(--ease), background-color .25s var(--ease);
}

.page-about .era-list a .num {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--text);
  letter-spacing: .02em;
}

.page-about .era-list a em {
  font-style: normal;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--cyan);
}

.page-about .era-list a:hover,
.page-about .era-list a:focus-visible {
  border-color: var(--amber);
  background: rgba(255, 139, 61, .1);
}

.page-about .spin-note {
  display: none;
}

.page-about .era-flow {
  position: relative;
  display: grid;
  gap: 16px;
  padding-left: var(--about-gutter);
}

.page-about .era-flow::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan), rgba(61, 231, 255, .12));
}

.page-about .rel-card {
  position: relative;
  padding: 18px 18px 16px;
  border: 1px solid var(--line);
  border-left: 2px solid rgba(159, 234, 245, .38);
  border-radius: var(--radius-m);
  background: var(--ink-800);
  transition: border-color .25s var(--ease), background-color .25s var(--ease), transform .25s var(--ease);
}

.page-about .rel-card::before {
  content: "";
  position: absolute;
  left: calc(var(--about-gutter) * -1 + 1px);
  top: 26px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--ink-900);
  border: 1px solid var(--cyan);
  box-shadow: 0 0 0 3px rgba(6, 20, 38, .9);
}

.page-about .rel-card:hover,
.page-about .rel-card:focus-within {
  border-color: var(--amber);
  border-left-color: var(--amber);
  background: var(--ink-700);
  transform: translateX(3px);
}

.page-about .rel-card:target {
  border-left-color: var(--cyan);
  box-shadow: inset 0 0 0 1px rgba(61, 231, 255, .28);
}

.page-about .rel-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 12px;
}

.page-about .rel-badge {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .1em;
  color: var(--ink-900);
  background: var(--cyan);
  padding: 3px 8px;
  border-radius: 4px;
}

.page-about .rel-head h3 {
  flex: 1 1 12em;
  margin: 0;
  font-size: 17px;
  line-height: 1.45;
  font-weight: 700;
  color: var(--text);
}

.page-about .rel-year {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--slate);
  letter-spacing: .04em;
}

.page-about .rel-body {
  margin: 12px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: #b9cbe0;
}

.page-about .rel-more {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px;
  margin: 12px 0 0;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
  font-size: 13px;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .rel-more .label {
  font-size: 10px;
  color: var(--cyan);
}

/* ---------- data band ---------- */
.page-about .data-band {
  position: relative;
  background:
    linear-gradient(180deg, rgba(10, 29, 54, .92), rgba(6, 20, 38, .98)),
    repeating-linear-gradient(90deg, rgba(159, 234, 245, .07) 0 1px, transparent 1px 72px),
    repeating-linear-gradient(0deg, rgba(159, 234, 245, .05) 0 1px, transparent 1px 72px);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .band-head {
  max-width: 44em;
}

.page-about .band-head h2 {
  margin: 12px 0 0;
  font-size: clamp(24px, 4.6vw, 36px);
  line-height: 1.22;
  letter-spacing: -.015em;
  font-weight: 800;
  color: var(--text);
}

.page-about .band-head p {
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--slate);
}

.page-about .band-grid {
  display: grid;
  gap: 22px;
  margin-top: clamp(24px, 4vw, 40px);
}

.page-about .band-figure {
  position: relative;
  margin: 0;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-l);
  overflow: hidden;
  background: var(--ink-800);
}

.page-about .band-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 10 / 7;
  object-fit: cover;
}

.page-about .band-stats {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .band-stats li {
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: rgba(18, 48, 82, .5);
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 2px 14px;
  align-items: baseline;
}

.page-about .band-stats .stat-num {
  grid-row: span 2;
  font-size: 32px;
  color: var(--amber);
}

.page-about .band-stats .stat-cap {
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--text);
}

.page-about .band-stats p {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--slate);
}

.page-about .band-flow {
  display: grid;
  gap: 14px;
  margin-top: 22px;
}

.page-about .flow-step {
  padding: 18px;
  border-top: 2px solid var(--cyan);
  background: rgba(6, 20, 38, .6);
  border-radius: 0 0 var(--radius-m) var(--radius-m);
}

.page-about .flow-idx {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--cyan);
}

.page-about .flow-step h3 {
  margin: 8px 0 0;
  font-size: 16px;
  font-weight: 700;
  color: var(--text);
}

.page-about .flow-step p {
  margin: 8px 0 0;
  font-size: 13px;
  line-height: 1.75;
  color: var(--slate);
}

/* ---------- team ---------- */
.page-about .team-head {
  max-width: 40em;
}

.page-about .team-head h2 {
  margin: 0;
  font-size: clamp(24px, 4.6vw, 36px);
  line-height: 1.2;
  letter-spacing: -.015em;
  font-weight: 800;
  color: var(--text);
}

.page-about .team-head p {
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--slate);
}

.page-about .team-bar {
  display: flex;
  height: 12px;
  margin-top: 26px;
  border-radius: 999px;
  overflow: hidden;
  background: var(--ink-800);
  border: 1px solid var(--line);
}

.page-about .team-bar span {
  display: block;
  height: 100%;
}

.page-about .tb-data { width: 42.86%; background: var(--cyan); }
.page-about .tb-prod { width: 38.10%; background: var(--mist); }
.page-about .tb-support { width: 19.04%; background: var(--amber); }

.page-about .team-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 20px;
  margin: 14px 0 0;
  padding: 0;
  list-style: none;
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--slate);
}

.page-about .team-legend li {
  display: inline-flex;
  align-items: center;
  gap: 7px;
}

.page-about .team-legend .num {
  font-family: var(--font-mono);
  color: var(--text);
}

.page-about .dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
}

.page-about .dot-data { background: var(--cyan); }
.page-about .dot-prod { background: var(--mist); }
.page-about .dot-support { background: var(--amber); }

.page-about .team-grid {
  display: grid;
  gap: 16px;
  margin-top: 26px;
}

.page-about .team-card {
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: var(--ink-800);
  transition: border-color .25s var(--ease);
}

.page-about .team-card:hover {
  border-color: var(--amber);
}

.page-about .team-tag {
  font-size: 10px;
  color: var(--mist);
}

.page-about .team-card h3 {
  margin: 10px 0 0;
  font-size: 17px;
  font-weight: 700;
  color: var(--text);
}

.page-about .team-card p {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: #b9cbe0;
}

/* ---------- eco ---------- */
.page-about .eco-grid {
  display: grid;
  gap: 22px;
  align-items: stretch;
}

.page-about .eco-copy {
  padding: clamp(22px, 4vw, 38px);
  border-radius: var(--radius-l);
  background: var(--paper);
  color: var(--ink-text);
}

.page-about .eco-copy h2 {
  margin: 10px 0 0;
  font-size: clamp(22px, 4.2vw, 32px);
  line-height: 1.25;
  letter-spacing: -.01em;
  font-weight: 800;
  color: var(--ink-text);
}

.page-about .eco-copy > p {
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: #17304e;
}

.page-about .eco-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px 16px;
  margin: 22px 0 0;
  padding: 18px 0 0;
  list-style: none;
  border-top: 1px solid var(--paper-line);
}

.page-about .eco-facts li {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.page-about .eco-facts .num {
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 600;
  line-height: 1.05;
  color: var(--ink-700);
}

.page-about .eco-facts .unit {
  font-size: .6em;
}

.page-about .eco-facts li span:last-child {
  font-size: 12px;
  letter-spacing: .06em;
  color: #4a6076;
}

.page-about .eco-figure {
  margin: 0;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-l);
  overflow: hidden;
  background: var(--ink-800);
}

.page-about .eco-figure img {
  display: block;
  width: 100%;
  height: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .eco-nodes {
  display: grid;
  gap: 14px;
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .eco-nodes li {
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: var(--ink-800);
  border-left: 2px solid var(--mist);
  transition: border-left-color .25s var(--ease), background-color .25s var(--ease);
}

.page-about .eco-nodes li:hover {
  border-left-color: var(--amber);
  background: var(--ink-700);
}

.page-about .node-kind {
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--cyan);
}

.page-about .eco-nodes strong {
  display: block;
  margin-top: 8px;
  font-size: 16px;
  color: var(--text);
}

.page-about .eco-nodes p {
  margin: 8px 0 0;
  font-size: 13px;
  line-height: 1.75;
  color: var(--slate);
}

/* ---------- next ---------- */
.page-about .next h2 {
  margin: 0 0 22px;
  font-size: clamp(22px, 4vw, 30px);
  font-weight: 800;
  letter-spacing: -.01em;
  color: var(--text);
}

.page-about .next-grid {
  display: grid;
  gap: 14px;
}

.page-about .next-card {
  display: block;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: var(--ink-800);
  text-decoration: none;
  transition: border-color .25s var(--ease), background-color .25s var(--ease);
}

.page-about .next-card strong {
  display: block;
  margin-top: 10px;
  font-size: 17px;
  color: var(--text);
}

.page-about .next-card p {
  margin: 8px 0 0;
  font-size: 13px;
  line-height: 1.75;
  color: var(--slate);
}

.page-about .next-go {
  display: inline-block;
  margin-top: 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--cyan);
}

.page-about .next-card:hover,
.page-about .next-card:focus-visible {
  border-color: var(--amber);
  background: var(--ink-700);
}

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

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

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

  .page-about .origin-line li {
    grid-template-columns: 56px minmax(0, 1fr);
  }
}

@media (min-width: 900px) {
  .page-about .hero-grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .85fr);
  }

  .page-about .band-grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    align-items: start;
  }

  .page-about .eco-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, .78fr);
  }

  .page-about .origin-body {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .origin-line li {
    grid-template-columns: 64px minmax(0, 1fr) minmax(0, 1.4fr);
    align-items: baseline;
  }

  .page-about .line-idx {
    grid-row: auto;
  }
}

@media (min-width: 960px) {
  .page-about {
    --about-gutter: 30px;
  }

  .page-about .era-grid {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: 44px;
  }

  .page-about .era-rail {
    position: sticky;
    top: calc(var(--header-h) + 28px);
    align-self: start;
    display: block;
    padding-right: 10px;
  }

  .page-about .rail-label {
    margin-bottom: 14px;
  }

  .page-about .era-list {
    display: grid;
    gap: 2px;
    overflow: visible;
  }

  .page-about .era-list a {
    display: flex;
    justify-content: space-between;
    padding: 9px 10px 9px 0;
    border: 0;
    border-bottom: 1px solid var(--line-soft);
    border-radius: 0;
    position: relative;
  }

  .page-about .era-list a::before {
    content: "";
    position: absolute;
    left: -10px;
    top: 50%;
    width: 4px;
    height: 4px;
    margin-top: -2px;
    border-radius: 50%;
    background: var(--line-strong);
    transition: background-color .25s var(--ease), transform .25s var(--ease);
  }

  .page-about .era-list a:hover::before,
  .page-about .era-list a:focus-visible::before {
    background: var(--amber);
    transform: scale(1.5);
  }

  .page-about .era-list a:hover,
  .page-about .era-list a:focus-visible {
    background: transparent;
  }

  .page-about .spin-note {
    display: block;
    margin: 26px 0 0;
    padding-left: 2px;
    writing-mode: vertical-rl;
    transform: rotate(180deg);
    font-size: 11px;
    letter-spacing: .28em;
    color: var(--line-strong);
    white-space: nowrap;
  }

  .page-about .timeline-head {
    padding-left: calc(var(--about-rail) + 44px);
  }
}