.page-about {
  --about-v3: #7C93D8;
  --about-v4: #C46E82;
  background: var(--ink-900);
  color: var(--paper);
  font-family: var(--font-body);
}

.page-about [id] {
  scroll-margin-top: 5.5rem;
}

.page-about .about-crumb {
  padding-top: 1.25rem;
}

.page-about .section-title {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 4.4vw, 2.5rem);
  line-height: 1.16;
  letter-spacing: 0.05em;
  margin: 0 0 0.85rem;
  color: var(--paper);
}

.page-about .section-sub {
  color: var(--mist);
  margin: 0 0 1.75rem;
  line-height: 1.8;
  max-width: 62ch;
}

.page-about .section-head .label {
  color: var(--amber);
  display: block;
  margin-bottom: 0.6rem;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: 1.5rem 0 2.75rem;
  border-bottom: 1px solid var(--rule-soft);
  background:
    radial-gradient(120% 90% at 10% 0%, rgba(200, 255, 77, 0.08), transparent 58%),
    linear-gradient(180deg, var(--ink-900) 0%, var(--ink-800) 100%);
}

.page-about .about-hero__grid {
  display: grid;
  gap: 2rem;
  align-items: start;
}

.page-about .about-hero__copy .label {
  color: var(--amber);
  display: block;
}

.page-about .about-hero__title {
  font-family: var(--font-display);
  font-size: clamp(2rem, 7.5vw, 4rem);
  line-height: 1.06;
  letter-spacing: 0.04em;
  margin: 0.55rem 0 1rem;
  color: var(--paper);
}

.page-about .about-hero__lede {
  font-size: 1.0625rem;
  line-height: 1.85;
  margin: 0 0 1.6rem;
  max-width: 54ch;
  color: var(--paper);
}

.page-about .about-anchors {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.page-about .about-anchors a {
  display: inline-block;
  padding: 0.4rem 0.75rem;
  border: 1px solid var(--rule);
  color: var(--mist);
  text-decoration: none;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.14em;
  transition: color 0.18s ease, border-color 0.18s ease, background-color 0.18s ease;
}

.page-about .about-anchors a:hover,
.page-about .about-anchors a:focus-visible {
  color: var(--lime);
  border-color: var(--lime);
  background: var(--lime-soft);
}

.page-about .about-board {
  border: 1px solid var(--rule);
  background: var(--ink-800);
  padding: 1.25rem 1.15rem 1.35rem;
  box-shadow: 9px 9px 0 rgba(62, 90, 80, 0.22);
}

.page-about .about-board__title {
  margin: 0 0 0.85rem;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--lime);
}

.page-about .about-board__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.75rem 0;
  border-top: 1px dashed var(--rule-soft);
}

.page-about .about-board__num {
  font-family: var(--font-mono);
  font-size: clamp(1.75rem, 6vw, 2.5rem);
  line-height: 1;
  color: var(--lime);
}

.page-about .about-board__label {
  font-size: var(--fs-14);
  line-height: 1.6;
  color: var(--mist);
  text-align: right;
}

/* ---------- 起步 ---------- */
.page-about .about-origin {
  padding: 2.75rem 0;
}

.page-about .origin {
  display: grid;
  gap: 1.75rem;
}

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

.page-about .origin__body .label {
  color: var(--amber);
  display: block;
  margin-bottom: 0.5rem;
}

.page-about .origin__body p {
  line-height: 1.85;
  margin: 0 0 1rem;
}

.page-about .origin__body ul {
  list-style: none;
  margin: 1.5rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.85rem;
}

.page-about .origin__body li {
  position: relative;
  padding-left: 1.5rem;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .origin__body li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 0.5rem;
  height: 0.5rem;
  background: var(--lime);
}

.page-about .origin__body li strong {
  color: var(--paper);
  font-weight: 600;
}

/* ---------- 版本演进 ---------- */
.page-about .about-versions {
  padding: 2.75rem 0;
  border-top: 1px solid var(--rule-soft);
  border-bottom: 1px solid var(--rule-soft);
  background:
    linear-gradient(180deg, rgba(90, 31, 43, 0.55) 0%, rgba(6, 17, 15, 0) 68%),
    var(--ink-900);
}

.page-about .versions {
  display: grid;
  gap: 1.5rem;
}

.page-about .rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 0.5rem;
  overflow-x: auto;
}

.page-about .rail__link {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 0.75rem;
  border: 1px solid var(--rule);
  color: var(--mist);
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.18s ease, border-color 0.18s ease, background-color 0.18s ease;
}

.page-about .rail__no {
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  letter-spacing: 0.08em;
  color: var(--lime);
}

.page-about .rail__name {
  font-size: var(--fs-14);
}

.page-about .rail__link:hover,
.page-about .rail__link:focus-visible {
  color: var(--paper);
  border-color: var(--lime);
  background: var(--lime-soft);
}

.page-about .versions__stages {
  display: grid;
  gap: 1.25rem;
}

.page-about .version {
  --stage: var(--lime);
  border: 1px solid var(--rule);
  border-left: 3px solid var(--stage);
  background: var(--ink-800);
  padding: 1.1rem 1.1rem 1.25rem;
  transition: background-color 0.18s ease, border-color 0.18s ease;
}

.page-about .version--v2 {
  --stage: var(--amber);
}

.page-about .version--v3 {
  --stage: var(--about-v3);
}

.page-about .version--v4 {
  --stage: var(--about-v4);
}

.page-about .version:hover {
  background: var(--ink-700);
}

.page-about .version__head {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 0.35rem 0.7rem;
  margin-bottom: 0.6rem;
}

.page-about .version__no {
  font-family: var(--font-mono);
  font-size: var(--fs-28);
  line-height: 1;
  letter-spacing: 0.06em;
  color: var(--stage);
}

.page-about .version__name {
  font-family: var(--font-display);
  font-size: var(--fs-20);
  letter-spacing: 0.06em;
  margin: 0;
}

.page-about .version__when {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--amber);
}

.page-about .version p {
  margin: 0 0 0.9rem;
  line-height: 1.82;
  color: var(--mist);
}

.page-about .version__spec {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0;
}

.page-about .version-figure {
  margin: 0.25rem 0;
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  padding: 2.75rem 0;
}

.page-about .team {
  display: grid;
  gap: 2rem;
}

.page-about .team__intro .label {
  color: var(--amber);
  display: block;
  margin-bottom: 0.5rem;
}

.page-about .team__intro p {
  line-height: 1.85;
  margin: 0 0 1rem;
}

.page-about .team__groups {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1.1rem;
}

.page-about .team-group {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0.2rem 0.85rem;
  border-top: 1px solid var(--rule);
  padding-top: 0.9rem;
}

.page-about .team-group__no {
  grid-row: span 2;
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  letter-spacing: 0.08em;
  color: var(--lime);
  padding-top: 0.15rem;
}

.page-about .team-group h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--fs-16);
  letter-spacing: 0.06em;
}

.page-about .team-group p {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 规模 ---------- */
.page-about .about-scale {
  padding: 2.75rem 0;
  border-top: 1px solid var(--rule-soft);
}

.page-about .scale-figure {
  margin: 0 0 2rem;
}

.page-about .scale-figure .figure__caption {
  padding-inline: var(--gutter);
}

.page-about .band {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  border-top: 1px solid var(--rule);
}

.page-about .band__cell {
  display: grid;
  gap: 0.3rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--rule-soft);
  transition: background-color 0.18s ease;
}

.page-about .band__cell:hover {
  background: var(--lime-soft);
}

.page-about .band__num {
  font-family: var(--font-mono);
  font-size: clamp(2rem, 7vw, 3rem);
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--lime);
}

.page-about .band__unit {
  font-size: 0.42em;
  margin-left: 0.18em;
  color: var(--paper);
}

.page-about .band__label {
  font-size: var(--fs-14);
  color: var(--paper);
}

.page-about .band__note {
  margin: 0;
  font-size: var(--fs-12);
  line-height: 1.65;
  color: var(--mist);
}

/* ---------- 日常效率 ---------- */
.page-about .about-habits {
  padding: 2.75rem 0;
  background: linear-gradient(180deg, rgba(20, 51, 43, 0.6) 0%, rgba(6, 17, 15, 0) 80%);
}

.page-about .habits {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1rem;
}

.page-about .habit {
  border: 1px solid var(--rule);
  background: var(--ink-800);
  padding: 1.1rem 1.1rem 1.3rem;
  transition: border-color 0.18s ease;
}

.page-about .habit:hover {
  border-color: var(--lime);
}

.page-about .habit__no {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--amber);
  margin-bottom: 0.5rem;
}

.page-about .habit h3 {
  margin: 0 0 0.5rem;
  font-family: var(--font-display);
  font-size: var(--fs-20);
  letter-spacing: 0.05em;
  line-height: 1.3;
}

.page-about .habit p {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.78;
  color: var(--mist);
}

/* ---------- 合作 ---------- */
.page-about .about-partners {
  padding: 2.75rem 0 3.5rem;
  border-top: 1px solid var(--rule-soft);
  background:
    linear-gradient(180deg, rgba(29, 42, 77, 0.8) 0%, rgba(6, 17, 15, 0) 88%),
    var(--ink-900);
}

.page-about .partners {
  display: grid;
  gap: 2rem;
}

.page-about .partners__intro .label {
  color: var(--amber);
  display: block;
  margin-bottom: 0.5rem;
}

.page-about .partners__intro p {
  line-height: 1.85;
  margin: 0 0 1.25rem;
}

.page-about .partners__actions {
  margin-bottom: 1.25rem;
}

.page-about .partners__outro {
  font-size: var(--fs-14);
  color: var(--mist);
  margin: 0;
}

.page-about .partners__outro a {
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.18s ease;
}

.page-about .partners__outro a:hover,
.page-about .partners__outro a:focus-visible {
  border-bottom-color: var(--lime);
}

.page-about .partners__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1.1rem;
}

.page-about .partners__item {
  border-left: 2px solid var(--amber);
  padding-left: 1rem;
}

.page-about .partners__item h3 {
  margin: 0 0 0.35rem;
  font-family: var(--font-display);
  font-size: var(--fs-20);
  letter-spacing: 0.05em;
}

.page-about .partners__item p {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.78;
  color: var(--mist);
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero,
  .page-about .about-origin,
  .page-about .about-versions,
  .page-about .about-team,
  .page-about .about-scale,
  .page-about .about-habits,
  .page-about .about-partners {
    padding-top: 3.5rem;
    padding-bottom: 3.5rem;
  }

  .page-about .band {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    column-gap: 1.75rem;
  }

  .page-about .band__cell {
    padding: 1.25rem 0.5rem 1.25rem 0;
  }

  .page-about .habits {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1.25rem;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 2.25rem 0 3.75rem;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(260px, 0.75fr);
    gap: 3.5rem;
    align-items: end;
  }

  .page-about .origin {
    grid-template-columns: minmax(220px, 320px) minmax(0, 1fr);
    gap: 3.5rem;
    align-items: start;
  }

  .page-about .team {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
    gap: 3.5rem;
    align-items: start;
  }

  .page-about .team__groups {
    gap: 1.35rem;
  }

  .page-about .partners {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 3.5rem;
    align-items: start;
  }
}

@media (min-width: 960px) {
  .page-about .versions {
    grid-template-columns: 168px minmax(0, 1fr);
    gap: 3rem;
    align-items: start;
  }

  .page-about .rail__list {
    position: sticky;
    top: 5.5rem;
    flex-direction: column;
    gap: 0;
    overflow: visible;
    border-left: 1px solid var(--rule);
  }

  .page-about .rail__link {
    border: 0;
    border-left: 2px solid transparent;
    padding: 0.6rem 0 0.6rem 0.9rem;
  }

  .page-about .rail__link:hover,
  .page-about .rail__link:focus-visible {
    background: transparent;
    border-left-color: var(--lime);
    color: var(--paper);
  }

  .page-about .version__name {
    font-size: var(--fs-28);
  }
}

@media (min-width: 1100px) {
  .page-about .band {
    grid-template-columns: repeat(6, minmax(0, 1fr));
    column-gap: 1.25rem;
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .about-anchors a,
  .page-about .rail__link,
  .page-about .version,
  .page-about .habit,
  .page-about .band__cell,
  .page-about .partners__outro a {
    transition: none;
  }
}
<<<END>>>