.page-about {
  --about-rail: 84px;
  --about-toc-w: 216px;
  background-color: var(--ink-deep);
  color: var(--bone);
}

.page-about .crumbs {
  padding-top: 16px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  border-bottom: 1px solid var(--rule);
  background:
    radial-gradient(72% 118% at 86% -6%, rgba(76, 255, 211, 0.13), transparent 62%),
    radial-gradient(48% 80% at 4% 104%, rgba(255, 177, 59, 0.07), transparent 62%);
}

.page-about .about-hero__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 5vw, 48px);
  padding-block: clamp(28px, 5vw, 52px) clamp(34px, 6vw, 76px);
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(2rem, 7.4vw, 4rem);
  line-height: 1.04;
  letter-spacing: -0.015em;
  margin: 14px 0 0;
  max-width: 16ch;
  text-wrap: balance;
}

.page-about .about-hero__deck {
  margin: 20px 0 0;
  max-width: 56ch;
  font-size: clamp(0.98rem, 1.6vw, 1.1rem);
  line-height: 1.8;
  color: rgba(233, 244, 239, 0.82);
}

.page-about .about-hero__stamp {
  margin-top: 26px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

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

.page-about .about-hero__figure img,
.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-figure {
  margin: 26px 0 0;
}

.page-about .media-frame__caption {
  margin-top: 10px;
  font-size: 0.8rem;
  line-height: 1.6;
  color: var(--mist);
}

/* ---------- 目录 + 章节骨架 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 40px);
  padding-block: clamp(30px, 5vw, 54px) clamp(48px, 8vw, 110px);
}

.page-about .about-toc {
  border-top: 2px solid var(--mint);
  padding-top: 14px;
}

.page-about .about-toc__title {
  margin: 0 0 12px;
  font-family: var(--font-data);
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .about-toc__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.page-about .about-toc__list li:last-child a {
  border-bottom: 1px solid var(--rule-soft);
}

.page-about .about-toc__list a {
  display: flex;
  align-items: baseline;
  gap: 9px;
  padding: 8px 0;
  border-bottom: 1px solid var(--rule-soft);
  color: var(--mist);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color var(--ease), border-color var(--ease);
}

.page-about .about-toc__list a:hover,
.page-about .about-toc__list a:focus-visible {
  color: var(--mint);
  border-color: var(--rule);
}

.page-about .about-toc__list a:focus-visible {
  outline: 2px solid var(--mint);
  outline-offset: 2px;
}

.page-about .about-toc__idx {
  font-family: var(--font-data);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  color: var(--teal);
}

.page-about .about-toc__note {
  margin: 14px 0 0;
  font-family: var(--font-data);
  font-size: 0.72rem;
  line-height: 1.9;
  color: rgba(156, 184, 174, 0.72);
}

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

.page-about .about-chapter {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 8px;
  padding-block: clamp(26px, 4vw, 46px);
  border-top: 1px solid var(--rule);
  scroll-margin-top: 18px;
}

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

.page-about .chapter-num {
  margin: 0;
  font-family: var(--font-data);
  font-size: 0.76rem;
  letter-spacing: 0.22em;
  color: var(--amber);
}

.page-about .chapter-main {
  min-width: 0;
}

.page-about .chapter-main > * + * {
  margin-top: 14px;
}

.page-about .chapter-main > h2 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.45rem, 4.2vw, 2.2rem);
  line-height: 1.16;
  letter-spacing: -0.01em;
  margin: 0;
  max-width: 24ch;
}

.page-about .chapter-main > p {
  margin: 0;
  font-size: 0.98rem;
  line-height: 1.8;
  color: rgba(233, 244, 239, 0.84);
  max-width: 68ch;
}

.page-about .chapter-main > p a {
  color: var(--mint);
  text-decoration: none;
  border-bottom: 1px solid var(--rule);
  transition: border-color var(--ease);
}

.page-about .chapter-main > p a:hover,
.page-about .chapter-main > p a:focus-visible {
  border-color: var(--mint);
}

.page-about .chapter-note {
  font-family: var(--font-data);
  font-size: 0.76rem;
  line-height: 1.7;
  color: var(--mist);
  padding-left: 12px;
  border-left: 2px solid var(--pine);
}

/* ---------- 分工表 ---------- */
.page-about .team-table-wrap {
  margin-top: 8px;
  overflow-x: auto;
}

.page-about .team-table {
  width: 100%;
  min-width: 520px;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.page-about .team-table caption {
  text-align: left;
  padding-bottom: 10px;
  font-family: var(--font-data);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--mist);
}

.page-about .team-table th,
.page-about .team-table td {
  text-align: left;
  vertical-align: top;
  padding: 12px 14px 12px 0;
  border-top: 1px solid var(--rule-soft);
  line-height: 1.65;
}

.page-about .team-table thead th {
  border-top: 0;
  border-bottom: 1px solid var(--rule);
  padding-top: 0;
  font-family: var(--font-data);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--teal);
}

.page-about .team-table tbody th {
  color: var(--bone);
  font-weight: 600;
  white-space: nowrap;
}

.page-about .team-table tbody td {
  color: rgba(233, 244, 239, 0.78);
}

.page-about .team-table tbody tr {
  transition: background var(--ease);
}

.page-about .team-table tbody tr:hover {
  background: rgba(76, 255, 211, 0.04);
}

/* ---------- 数据链路 ---------- */
.page-about .flow {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
}

.page-about .flow__item {
  position: relative;
  padding: 14px 0 14px 24px;
  border-left: 1px solid var(--rule);
  transition: border-color var(--ease), background-color var(--ease);
}

.page-about .flow__item::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 22px;
  width: 7px;
  height: 7px;
  background-color: var(--teal);
  transition: background-color var(--ease);
}

.page-about .flow__item:hover,
.page-about .flow__item:focus-within {
  border-color: var(--mint);
  background: linear-gradient(90deg, rgba(76, 255, 211, 0.07), transparent 72%);
}

.page-about .flow__item:hover::before,
.page-about .flow__item:focus-within::before {
  background-color: var(--amber);
}

.page-about .flow__tag {
  display: block;
  margin-bottom: 5px;
  font-family: var(--font-data);
  font-size: 0.74rem;
  letter-spacing: 0.16em;
  color: var(--mint);
}

.page-about .flow__item p {
  margin: 0;
  font-size: 0.93rem;
  line-height: 1.72;
  color: rgba(233, 244, 239, 0.8);
  max-width: 62ch;
}

/* ---------- 版本演进 ---------- */
.page-about .versions {
  display: grid;
  gap: 1px;
  background-color: var(--rule-soft);
  border: 1px solid var(--rule-soft);
}

.page-about .version {
  padding: 20px 18px 22px;
  background-color: var(--ink-stand);
  transition: background-color var(--ease), box-shadow var(--ease);
}

.page-about .version:hover {
  background-color: var(--ink-board);
  box-shadow: inset 0 0 0 1px var(--rule);
}

.page-about .version--now {
  background:
    linear-gradient(158deg, rgba(76, 255, 211, 0.13), rgba(18, 184, 146, 0.03) 62%),
    var(--ink-board);
  box-shadow: inset 0 0 0 1px var(--rule);
}

.page-about .version__year {
  margin: 0 0 8px;
  font-family: var(--font-data);
  font-size: 1.3rem;
  letter-spacing: 0.02em;
  color: var(--mint);
}

.page-about .version--now .version__year {
  color: var(--amber);
}

.page-about .version h3 {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 600;
  line-height: 1.4;
  color: var(--bone);
}

.page-about .version p {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.72;
  color: rgba(233, 244, 239, 0.76);
}

.page-about .chapter-main > p .btn {
  margin-top: 4px;
}

/* ---------- 服务范围 ---------- */
.page-about .range-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background-color: var(--rule-soft);
  border: 1px solid var(--rule-soft);
}

.page-about .range-stats li {
  display: grid;
  gap: 4px;
  padding: 16px 14px 18px;
  background-color: var(--ink-stand);
  transition: background-color var(--ease);
}

.page-about .range-stats li:hover {
  background-color: var(--ink-board);
}

.page-about .range-stats .stat-num {
  font-family: var(--font-data);
  font-size: clamp(1.5rem, 4.4vw, 2rem);
  line-height: 1;
  color: var(--mint);
  font-variant-numeric: tabular-nums;
}

.page-about .range-stats li:last-child .stat-num {
  color: var(--amber);
}

.page-about .range-stats__unit {
  font-size: 0.82rem;
  letter-spacing: 0.02em;
  color: var(--mist);
}

/* ---------- 合作与联系 ---------- */
.page-about .routes {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background-color: var(--rule-soft);
  border: 1px solid var(--rule-soft);
}

.page-about .routes a {
  display: grid;
  gap: 4px;
  padding: 15px 16px;
  background-color: var(--ink-stand);
  text-decoration: none;
  transition: background-color var(--ease), box-shadow var(--ease);
}

.page-about .routes a:hover,
.page-about .routes a:focus-visible {
  background-color: var(--ink-board);
  box-shadow: inset 2px 0 0 0 var(--mint);
}

.page-about .routes a:focus-visible {
  outline: 2px solid var(--mint);
  outline-offset: -2px;
}

.page-about .routes__label {
  font-size: 0.96rem;
  font-weight: 600;
  color: var(--bone);
}

.page-about .routes a:hover .routes__label,
.page-about .routes a:focus-visible .routes__label {
  color: var(--mint);
}

.page-about .routes__hint {
  font-size: 0.82rem;
  line-height: 1.6;
  color: var(--mist);
}

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

.page-about .contact-list li {
  display: grid;
  gap: 3px;
  padding: 12px 0;
  border-bottom: 1px solid var(--rule-soft);
}

.page-about .contact-list__key {
  font-family: var(--font-data);
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--teal);
}

.page-about .contact-list__val {
  font-family: var(--font-data);
  font-size: 0.92rem;
  color: var(--bone);
  overflow-wrap: anywhere;
}

.page-about .contact-list__val--text {
  font-family: var(--font-body);
  font-size: 0.92rem;
  color: rgba(233, 244, 239, 0.84);
}

/* ---------- 宽屏 ---------- */
@media (min-width: 720px) {
  .page-about .about-chapter {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    column-gap: clamp(18px, 3vw, 40px);
  }

  .page-about .chapter-num {
    padding-top: 8px;
  }

  .page-about .flow {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: 22px;
  }

  .page-about .contact-list li {
    grid-template-columns: 76px minmax(0, 1fr);
    align-items: baseline;
    gap: 14px;
  }
}

@media (min-width: 760px) {
  .page-about .versions {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

@media (min-width: 980px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 6.2fr) minmax(0, 5fr);
    align-items: end;
    gap: clamp(36px, 5vw, 72px);
  }
}

@media (min-width: 1024px) {
  .page-about .about-body {
    grid-template-columns: var(--about-toc-w) minmax(0, 1fr);
    gap: clamp(32px, 4vw, 64px);
  }

  .page-about .about-toc {
    position: sticky;
    top: 20px;
    align-self: start;
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .about-toc__list a,
  .page-about .flow__item,
  .page-about .flow__item::before,
  .page-about .version,
  .page-about .range-stats li,
  .page-about .routes a,
  .page-about .team-table tbody tr {
    transition: none;
  }
}
<<<END>>>