.page-about {
  --about-rail: 218px;
  --about-gap: clamp(20px, 3.4vw, 44px);
  background: var(--ink-900);
  color: var(--text);
  font-family: var(--font-sans);
  padding-bottom: clamp(32px, 5vw, 72px);
}

.page-about .crumbs {
  margin: clamp(14px, 2.4vw, 24px) 0 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: clamp(14px, 2.4vw, 28px);
  padding: clamp(18px, 3vw, 34px) 0 clamp(32px, 5vw, 64px);
  border-bottom: 1px solid var(--line);
}

.page-about .about-hero__rail {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--signal);
}

.page-about .about-hero__no {
  color: var(--orange);
}

.page-about .about-hero__line {
  flex: 1;
  height: 1px;
  background: var(--line);
}

.page-about .about-hero__tag {
  color: var(--muted);
  letter-spacing: 0.2em;
}

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

.page-about .about-hero__lead h1 {
  margin: 14px 0 0;
  font-size: clamp(30px, 4.8vw, 56px);
  line-height: 1.14;
  font-weight: 900;
  letter-spacing: -0.015em;
  max-width: 15em;
}

.page-about .about-hero__intro {
  margin: clamp(14px, 2vw, 22px) 0 0;
  max-width: 60ch;
  font-size: clamp(15.5px, 1.5vw, 17px);
  line-height: 1.9;
  color: var(--muted);
}

.page-about .about-facts {
  list-style: none;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-fact {
  background: var(--ink-800);
  padding: 14px 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 0;
}

.page-about .about-fact__num {
  font-family: var(--font-mono);
  font-size: clamp(22px, 2.6vw, 30px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--lime);
}

.page-about .about-fact__label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 主体两栏 ---------- */
.page-about .about-body {
  display: grid;
  gap: clamp(16px, 3vw, 40px);
  padding-top: clamp(20px, 3vw, 36px);
}

.page-about .about-rail {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line);
  scrollbar-width: thin;
}

.page-about .about-rail__link {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 7px 12px 8px;
  border: 1px solid var(--line);
  background: var(--glass);
  color: var(--text);
  font-size: 13px;
  line-height: 1.5;
  text-decoration: none;
  white-space: nowrap;
  transition: color var(--ease), border-color var(--ease), background var(--ease), transform var(--ease);
}

.page-about .about-rail__no {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--signal);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--orange);
  border-color: var(--orange);
  transform: translateY(-2px);
}

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

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  padding: clamp(30px, 4.6vw, 60px) 0;
  border-top: 1px solid var(--line);
  scroll-margin-top: 96px;
}

.page-about .about-chapter:first-child {
  border-top: 0;
  padding-top: clamp(10px, 1.6vw, 18px);
}

.page-about .chapter-head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: clamp(12px, 2vw, 20px);
}

.page-about .chapter-no {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--signal);
}

.page-about .chapter-title {
  margin: 0;
  font-size: clamp(21px, 2.9vw, 31px);
  line-height: 1.3;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.page-about .chapter-lead {
  margin: 0;
  max-width: 62ch;
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--muted);
}

/* ---------- 三件诉求 ---------- */
.page-about .about-asks {
  list-style: none;
  margin: clamp(18px, 2.6vw, 28px) 0 0;
  padding: 0;
}

.page-about .about-ask {
  padding: clamp(16px, 2.2vw, 22px) 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-ask:first-child {
  border-top: 1px solid var(--line);
}

.page-about .about-ask__k {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: clamp(16px, 1.8vw, 18px);
  font-weight: 700;
  color: var(--text);
}

.page-about .about-ask__no {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 400;
  color: var(--orange);
}

.page-about .about-ask__p {
  margin: 8px 0 0;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.9;
  color: var(--muted);
}

/* ---------- 图形 ---------- */
.page-about .about-figure {
  margin: clamp(18px, 2.8vw, 28px) 0 0;
}

.page-about .about-figure--team,
.page-about .about-figure--ui {
  margin: 0;
}

/* ---------- 版本卡 ---------- */
.page-about .about-versions {
  display: grid;
  gap: 14px;
  margin-top: clamp(22px, 3.2vw, 36px);
}

.page-about .ver-card {
  border-top: 2px solid var(--line);
  padding: 16px 0 0;
  min-width: 0;
  transition: border-color var(--ease), background var(--ease), transform var(--ease);
  scroll-margin-top: 96px;
}

.page-about .ver-card:hover {
  border-top-color: var(--signal);
  transform: translateY(-2px);
}

.page-about .ver-card__head {
  display: flex;
  align-items: center;
  gap: 10px;
}

.page-about .ver-card__v {
  font-family: var(--font-mono);
  font-size: 19px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--signal);
}

.page-about .ver-card__title {
  margin: 8px 0 8px;
  font-size: 17px;
  font-weight: 800;
  line-height: 1.4;
  color: var(--text);
}

.page-about .ver-card__p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--muted);
  overflow-wrap: break-word;
}

.page-about .ver-card.is-current {
  border-top-color: var(--orange);
  background: var(--ink-700);
  padding: 16px;
  box-shadow: inset 0 0 0 1px var(--glass);
}

.page-about .ver-card.is-current .ver-card__v {
  color: var(--orange);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  display: grid;
  gap: clamp(18px, 2.6vw, 28px);
  margin-top: clamp(18px, 2.8vw, 30px);
}

.page-about .team-stack {
  border: 1px solid var(--line);
  background: var(--ink-800);
  padding: clamp(12px, 2vw, 18px);
  min-width: 0;
}

.page-about .team-stack__layer {
  border: 1px solid var(--line);
  padding: clamp(12px, 1.8vw, 18px);
  min-width: 0;
  transition: border-color var(--ease), background var(--ease), transform var(--ease);
}

.page-about .team-stack__layer--mid {
  margin-top: 12px;
  background: var(--glass);
}

.page-about .team-stack__layer--inner {
  margin-top: 12px;
  background: var(--ink-700);
}

.page-about .team-stack__layer:hover {
  border-color: var(--orange);
  transform: translateY(-2px);
}

.page-about .team-stack__tag {
  display: inline-block;
  font-size: 14.5px;
  font-weight: 800;
  letter-spacing: 0.01em;
  color: var(--text);
}

.page-about .team-stack__note {
  margin: 8px 0 0;
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 覆盖 ---------- */
.page-about .about-coverage {
  display: grid;
  gap: clamp(18px, 2.6vw, 28px);
  margin-top: clamp(14px, 2vw, 22px);
}

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

.page-about .about-coverage__p {
  margin: 14px 0 0;
  max-width: 60ch;
  font-size: 15px;
  line-height: 1.9;
  color: var(--muted);
}

.page-about .dotgrid {
  display: grid;
  grid-template-columns: repeat(8, minmax(0, 1fr));
  gap: clamp(8px, 1.4vw, 14px);
  margin-top: clamp(18px, 2.6vw, 26px);
  padding: clamp(12px, 2vw, 18px);
  border: 1px solid var(--line);
  background: var(--ink-800);
}

.page-about .dotgrid__dot {
  display: block;
  width: 100%;
  aspect-ratio: 1 / 1;
  border-radius: 50%;
  background: var(--signal);
  opacity: 0.34;
  justify-self: center;
}

.page-about .dotgrid__dot--sm {
  width: 42%;
}

.page-about .dotgrid__dot--md {
  width: 70%;
  opacity: 0.58;
}

.page-about .dotgrid__dot--lg {
  width: 100%;
  opacity: 0.9;
  background: var(--signal);
}

.page-about .dotgrid__dot--hot {
  width: 84%;
  opacity: 1;
  background: var(--orange);
}

/* ---------- 合作 ---------- */
.page-about .about-partners {
  display: grid;
  gap: 10px;
  margin-top: clamp(18px, 2.6vw, 26px);
}

.page-about .partner {
  border: 1px solid var(--line);
  background: var(--ink-800);
  min-width: 0;
  transition: border-color var(--ease), background var(--ease);
}

.page-about .partner[open] {
  border-color: var(--orange);
  background: var(--ink-700);
}

.page-about .partner__sum {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 14px 16px;
  font-size: 15.5px;
  font-weight: 700;
  color: var(--text);
  cursor: pointer;
  list-style: none;
}

.page-about .partner__sum::-webkit-details-marker {
  display: none;
}

.page-about .partner__sum::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 18px;
  line-height: 1;
  color: var(--orange);
}

.page-about .partner[open] .partner__sum::after {
  content: "–";
}

.page-about .partner__sum:focus-visible {
  outline: 2px solid var(--orange);
  outline-offset: -2px;
}

.page-about .partner__no {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 400;
  color: var(--signal);
}

.page-about .partner__body {
  padding: 0 16px 16px 44px;
  border-left: 1px solid var(--signal);
  margin-left: 16px;
}

.page-about .partner__body p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--muted);
}

/* ---------- 三条做法与行动点 ---------- */
.page-about .about-principles {
  display: grid;
  margin-top: clamp(16px, 2.4vw, 24px);
}

.page-about .principle {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 10px;
  padding: clamp(16px, 2.2vw, 22px) 0;
  border-top: 1px solid var(--line);
}

.page-about .principle:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .principle__no {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--orange);
  padding-top: 3px;
}

.page-about .principle__title {
  margin: 0;
  font-size: 17px;
  font-weight: 800;
  line-height: 1.45;
  color: var(--text);
}

.page-about .principle__p {
  margin: 6px 0 0;
  max-width: 56ch;
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--muted);
}

.page-about .about-next__lead {
  margin: clamp(22px, 3.2vw, 34px) 0 0;
  max-width: 56ch;
  font-size: 15px;
  line-height: 1.9;
  color: var(--text);
}

.page-about .about-next {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 18px;
  margin-top: 18px;
}

.page-about .about-next__link {
  color: var(--text);
  font-size: 14.5px;
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
  transition: color var(--ease), text-decoration-thickness var(--ease);
}

.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  color: var(--orange);
  text-decoration-thickness: 2px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    align-items: start;
    gap: var(--about-gap);
  }

  .page-about .about-hero__rail {
    flex-direction: column;
    align-items: flex-start;
    align-self: stretch;
    padding-top: 6px;
  }

  .page-about .about-hero__line {
    width: 1px;
    height: auto;
    flex: 1;
    min-height: 90px;
  }

  .page-about .about-hero__tag {
    writing-mode: vertical-rl;
    letter-spacing: 0.28em;
  }
}

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

  .page-about .about-rail {
    position: sticky;
    top: 92px;
    flex-direction: column;
    gap: 0;
    overflow: visible;
    border-bottom: 0;
    border-left: 1px solid var(--line);
    padding: 0 0 0 14px;
  }

  .page-about .about-rail__link {
    border: 0;
    border-bottom: 1px solid transparent;
    background: transparent;
    padding: 11px 0;
    justify-content: flex-start;
    white-space: normal;
    transition: color var(--ease), border-color var(--ease), padding-left var(--ease);
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    border-bottom-color: var(--orange);
    padding-left: 6px;
    transform: none;
  }

  .page-about .about-versions {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 16px;
    align-items: start;
  }

  .page-about .ver-card:nth-child(2) {
    margin-top: 30px;
  }

  .page-about .ver-card:nth-child(3) {
    margin-top: 60px;
  }

  .page-about .ver-card:nth-child(4) {
    margin-top: 90px;
  }

  .page-about .about-team {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    align-items: start;
  }

  .page-about .about-coverage {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.86fr);
    align-items: start;
    gap: clamp(24px, 3.4vw, 44px);
  }

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

@media (min-width: 1180px) {
  .page-about .about-chapter #audience,
  .page-about .about-asks {
    max-width: 760px;
  }

  .page-about .about-chapter .chapter-lead {
    max-width: 64ch;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .ver-card,
  .page-about .team-stack__layer {
    transition: none;
  }

  .page-about .about-rail__link:hover,
  .page-about .ver-card:hover,
  .page-about .team-stack__layer:hover {
    transform: none;
  }
}
<<<END>>>