.page-about {
  --about-gap: 24px;
  background-color: var(--night);
  color: var(--ink);
  padding-bottom: var(--sp-5);
  overflow-x: clip;
}

.page-about .about-hero {
  padding-block: var(--sp-3) var(--sp-4);
}

.page-about .about-hero__grid {
  display: grid;
  gap: var(--sp-3);
  align-items: center;
}

.page-about .about-hero__lead h1 {
  font-family: var(--serif);
  font-weight: 800;
  font-size: clamp(1.85rem, 7vw, 3rem);
  line-height: 1.18;
  letter-spacing: 0.01em;
  color: var(--ice);
  margin: 10px 0 14px;
  max-width: 20ch;
}

.page-about .about-hero__lead .lede {
  max-width: 44ch;
}

.page-about .hero-facts {
  list-style: none;
  margin: var(--sp-3) 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .hero-facts li {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 8px 16px;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  background: var(--panel);
  font-size: 0.82rem;
  color: var(--mist);
  white-space: nowrap;
}

.page-about .hero-facts .num {
  font-family: var(--mono);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--amber);
}

.page-about .hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: var(--sp-3);
}

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

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

.page-about .chapters {
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
}

.page-about .chapter {
  position: relative;
  padding: var(--sp-3);
  border: 1px solid var(--line);
  border-radius: var(--r-panel);
  background:
    radial-gradient(120% 90% at 100% 0%, rgba(53, 208, 192, 0.07) 0%, transparent 58%),
    linear-gradient(165deg, var(--panel) 0%, #0d1631 100%);
  overflow: hidden;
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .chapter:hover,
.page-about .chapter:focus-within {
  border-color: rgba(53, 208, 192, 0.55);
}

.page-about .chapter__no {
  position: absolute;
  top: 4px;
  right: 14px;
  font-family: var(--mono);
  font-size: clamp(3.2rem, 13vw, 5.4rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.04em;
  color: rgba(53, 208, 192, 0.11);
  pointer-events: none;
  user-select: none;
  transition: color var(--dur) var(--ease);
}

.page-about .chapter:hover .chapter__no,
.page-about .chapter:focus-within .chapter__no {
  color: rgba(53, 208, 192, 0.3);
}

.page-about .chapter__inner {
  position: relative;
  z-index: 1;
}

.page-about .chapter__head h2 {
  font-family: var(--serif);
  font-weight: 700;
  font-size: clamp(1.4rem, 4.6vw, 2rem);
  line-height: 1.28;
  color: var(--ice);
  margin: 8px 0 0;
  max-width: 24ch;
}

.page-about .chapter__grid {
  display: grid;
  gap: var(--sp-3);
  margin-top: var(--sp-3);
}

.page-about .chapter__inner > .prose {
  margin-top: var(--sp-2);
}

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

.page-about .stat-rows {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .stat-row {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  column-gap: 10px;
  padding: 11px 0;
  border-bottom: 1px solid var(--line);
  transition: border-color var(--dur) var(--ease);
}

.page-about .stat-row:hover {
  border-bottom-color: var(--cyan);
}

.page-about .stat-row__k {
  flex: 0 0 100%;
  margin: 0;
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  color: var(--mist);
}

.page-about .stat-row__v {
  margin: 2px 0 0;
  font-family: var(--mono);
  font-size: 1.15rem;
  color: var(--pure);
}

.page-about .stat-row__v .num {
  font-size: 1.45rem;
  font-weight: 700;
  color: var(--amber);
}

.page-about .stat-row__hint {
  flex: 1 0 100%;
  margin: 4px 0 0;
  font-size: 0.78rem;
  line-height: 1.55;
  color: rgba(142, 156, 192, 0.6);
  transition: color var(--dur) var(--ease);
}

.page-about .stat-row:hover .stat-row__hint {
  color: var(--cyan);
}

.page-about .pipeline {
  list-style: none;
  margin: var(--sp-3) 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .pipeline__step {
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--cyan-deep);
  border-radius: var(--r-card);
  background: rgba(10, 17, 40, 0.5);
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .pipeline__step:hover {
  border-color: var(--line);
  border-left-color: var(--cyan);
  background: rgba(10, 17, 40, 0.85);
}

.page-about .pipeline__time {
  display: inline-block;
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  color: var(--amber);
}

.page-about .pipeline__step h3 {
  margin: 6px 0 6px;
  font-family: var(--sans);
  font-size: 1rem;
  font-weight: 600;
  color: var(--ice);
}

.page-about .pipeline__step p {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.7;
  color: var(--ink);
}

.page-about .iteration__layout {
  display: grid;
  gap: var(--sp-3);
  margin-top: var(--sp-3);
}

.page-about .iteration {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .iteration__item {
  position: relative;
  padding-left: 34px;
  padding-bottom: 14px;
}

.page-about .iteration__item::before {
  content: "";
  position: absolute;
  left: 1px;
  top: 12px;
  width: 11px;
  height: 11px;
  border-radius: var(--r-pill);
  background: var(--night);
  border: 2px solid var(--line);
  box-sizing: border-box;
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .iteration__item::after {
  content: "";
  position: absolute;
  left: 6px;
  top: 28px;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--line), rgba(34, 51, 95, 0.2));
}

.page-about .iteration__item:last-child {
  padding-bottom: 0;
}

.page-about .iteration__item:last-child::after {
  display: none;
}

.page-about .iteration__item:has(details[open])::before {
  border-color: var(--amber);
  background: var(--amber);
}

.page-about .iteration__card {
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  background: rgba(10, 17, 40, 0.45);
  transition: border-color var(--dur) var(--ease);
}

.page-about .iteration__card:hover {
  border-color: rgba(53, 208, 192, 0.5);
}

.page-about .iteration__card > summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  padding: 12px 16px;
  cursor: pointer;
  list-style: none;
}

.page-about .iteration__card > summary::-webkit-details-marker {
  display: none;
}

.page-about .iteration__ver {
  font-family: var(--mono);
  font-size: 0.86rem;
  font-weight: 700;
  color: var(--cyan);
}

.page-about .iteration__title {
  font-family: var(--sans);
  font-size: 1rem;
  font-weight: 600;
  color: var(--ice);
}

.page-about .iteration__desc {
  margin: 0;
  padding: 0 16px 14px;
  font-size: 0.86rem;
  line-height: 1.7;
  color: var(--ink);
}

.page-about .roles {
  list-style: none;
  margin: var(--sp-3) 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .role {
  padding: 18px 16px 16px;
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  background: linear-gradient(180deg, rgba(18, 28, 61, 0.9), rgba(10, 17, 40, 0.6));
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .role:hover {
  transform: translateY(-2px);
  border-color: var(--cyan);
}

.page-about .role__no {
  margin: 0;
  font-family: var(--mono);
  font-size: 2.1rem;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--amber);
}

.page-about .role__title {
  margin: 10px 0 6px;
  font-family: var(--sans);
  font-size: 1rem;
  font-weight: 600;
  color: var(--ice);
}

.page-about .role__text {
  margin: 0;
  font-size: 0.86rem;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .chapter--gateway {
  background:
    radial-gradient(100% 120% at 0% 0%, rgba(200, 16, 46, 0.16) 0%, transparent 55%),
    linear-gradient(165deg, var(--panel) 0%, #0d1631 100%);
}

.page-about .gateways {
  list-style: none;
  margin: var(--sp-3) 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .gateways a {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px 12px;
  padding: 15px 18px;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  background: rgba(10, 17, 40, 0.55);
  text-decoration: none;
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .gateways a:hover,
.page-about .gateways a:focus-visible {
  border-color: var(--cyan);
  background: rgba(15, 124, 114, 0.14);
}

.page-about .gateways__label {
  font-family: var(--sans);
  font-size: 1rem;
  font-weight: 600;
  color: var(--ice);
}

.page-about .gateways__note {
  flex: 1 1 100%;
  font-size: 0.8rem;
  line-height: 1.6;
  color: var(--mist);
}

.page-about .gateways__arrow {
  margin-left: auto;
  font-family: var(--mono);
  color: var(--cyan);
  transition: transform var(--dur) var(--ease);
}

.page-about .gateways a:hover .gateways__arrow {
  transform: translateX(4px);
}

.page-about .gateways__foot {
  margin: var(--sp-3) 0 0;
  font-size: 0.85rem;
  color: var(--mist);
}

.page-about .gateways__foot a {
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

@media (min-width: 640px) {
  .page-about .stat-row__k {
    flex: 0 0 auto;
    min-width: 7.5em;
  }

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

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

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

@media (min-width: 900px) {
  .page-about .about-hero {
    padding-block: var(--sp-4) var(--sp-4);
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    gap: var(--sp-4);
  }

  .page-about .chapter {
    padding: var(--sp-4) var(--sp-4) var(--sp-3);
  }

  .page-about .chapter:nth-child(1) {
    width: 90%;
    margin-left: 0;
  }

  .page-about .chapter:nth-child(2) {
    width: 80%;
    margin-left: 16%;
  }

  .page-about .chapter:nth-child(3) {
    width: 92%;
    margin-left: 3%;
  }

  .page-about .chapter:nth-child(4) {
    width: 84%;
    margin-left: 10%;
  }

  .page-about .chapter:nth-child(5) {
    width: 100%;
    margin-left: 0;
  }

  .page-about .chapter:nth-child(6) {
    width: 78%;
    margin-left: 18%;
  }

  .page-about .chapter:nth-child(7) {
    width: 91%;
    margin-left: 2%;
  }

  .page-about .chapter__grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    gap: var(--sp-4);
  }

  .page-about .chapter__grid--media {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
    align-items: center;
  }

  .page-about .iteration__layout {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
    gap: var(--sp-4);
    align-items: start;
  }

  .page-about .pipeline {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .pipeline__step {
    display: flex;
    flex-direction: column;
  }
}

@media (min-width: 1180px) {
  .page-about .chapters {
    gap: var(--sp-4);
  }
}
</main>