.page-about {
  --about-line: rgba(22, 18, 27, 0.14);
  --about-line-gold: rgba(201, 162, 39, 0.45);
  background-color: var(--ivory);
  color: var(--ink);
  font-family: var(--font-body);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  background: radial-gradient(circle at 82% 18%, rgba(74, 44, 122, 0.85), transparent 62%), var(--purple);
  color: var(--ivory);
  padding-block: clamp(1.25rem, 3vw, 2rem) clamp(2.5rem, 6vw, 4.5rem);
  border-bottom: var(--rule) solid var(--gold);
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 7px;
  background-image: repeating-linear-gradient(90deg, var(--gold) 0 1px, transparent 1px 26px);
  opacity: 0.5;
  pointer-events: none;
}

.page-about .about-hero .breadcrumbs {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  margin-bottom: clamp(1.5rem, 4vw, 2.75rem);
}

.page-about .about-hero .breadcrumbs__link {
  color: var(--gold-light);
  text-decoration: none;
}

.page-about .about-hero .breadcrumbs__sep {
  color: rgba(231, 206, 123, 0.5);
  margin: 0 0.5rem;
}

.page-about .about-hero .eyebrow {
  color: var(--gold-light);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(1.75rem, 4vw, 3rem);
  align-items: end;
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.95rem, 5.2vw, 3.7rem);
  line-height: 1.14;
  letter-spacing: -0.02em;
  margin: 0.8rem 0 0;
}

.page-about .about-hero__lead {
  margin: 1.25rem 0 0;
  max-width: 36em;
  font-size: clamp(1rem, 1.4vw, 1.0625rem);
  line-height: 1.85;
  color: rgba(246, 241, 231, 0.86);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.75rem;
}

.page-about .about-card {
  position: relative;
  background-color: rgba(22, 18, 27, 0.4);
  border: var(--rule) solid var(--gold);
  padding: clamp(1.25rem, 3vw, 1.6rem);
}

.page-about .about-card .frame__label {
  color: var(--gold-light);
  margin: 0 0 0.75rem;
}

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

.page-about .about-card__item {
  border-top: 1px solid rgba(201, 162, 39, 0.3);
  padding-top: 0.85rem;
}

.page-about .about-card__item:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .about-card__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 3.2vw, 1.9rem);
  line-height: 1.1;
  color: var(--gold-light);
  letter-spacing: 0.04em;
}

.page-about .about-card__unit {
  font-family: var(--font-body);
  font-size: 0.78rem;
  margin-left: 0.3rem;
  color: rgba(231, 206, 123, 0.75);
}

.page-about .about-card__key {
  display: block;
  margin-top: 0.35rem;
  font-size: 0.85rem;
  line-height: 1.6;
  color: rgba(246, 241, 231, 0.74);
}

/* ---------- 主体两栏 ---------- */
.page-about .about-layout {
  display: grid;
  gap: clamp(1.75rem, 4vw, 3rem);
  padding-block: clamp(2.25rem, 5vw, 4rem) clamp(1rem, 2vw, 1.5rem);
}

.page-about .about-rail {
  align-self: start;
  border-top: var(--rule) solid var(--ink);
  padding-top: 0.85rem;
}

.page-about .about-rail .mono-label {
  color: var(--purple-mid);
}

.page-about .about-rail__nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.15rem 0.9rem;
  margin-top: 0.7rem;
}

.page-about .about-rail__nav a {
  position: relative;
  display: block;
  padding: 0.35rem 0 0.35rem 0.85rem;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.06em;
  color: var(--muted);
  text-decoration: none;
  transition: color 160ms ease;
}

.page-about .about-rail__nav a::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 6px;
  height: 1.5px;
  background-color: var(--about-line-gold);
  transform: translateY(-50%);
  transition: width 160ms ease, background-color 160ms ease;
}

.page-about .about-rail__nav a:hover,
.page-about .about-rail__nav a:focus-visible {
  color: var(--purple);
}

.page-about .about-rail__nav a:hover::before,
.page-about .about-rail__nav a[aria-current="true"]::before {
  width: 14px;
  height: 2px;
  background-color: var(--gold);
}

.page-about .about-rail__nav a[aria-current="true"] {
  color: var(--purple);
  font-weight: 700;
}

.page-about .about-rail__note {
  margin: 1.1rem 0 0;
  padding-left: 0.8rem;
  border-left: 2px solid var(--about-line-gold);
  font-size: 0.82rem;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 通用章节 ---------- */
.page-about .about-section {
  padding-block: clamp(1.5rem, 3vw, 2.25rem);
}

.page-about .about-flow .about-section:first-child {
  padding-top: 0;
}

.page-about .about-flow .about-section + .about-section {
  border-top: 1px solid var(--about-line);
}

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

.page-about .about-section .eyebrow {
  color: var(--purple-mid);
}

.page-about .about-section h2 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.4rem, 3.1vw, 2.1rem);
  line-height: 1.28;
  letter-spacing: -0.01em;
  margin: 0.5rem 0 0;
}

.page-about .about-section__lead {
  margin: 1rem 0 0;
  max-width: 38em;
  font-size: clamp(1rem, 1.3vw, 1.0625rem);
  line-height: 1.85;
  color: var(--ink);
}

.page-about .about-section__body {
  margin-top: 1rem;
}

.page-about .prose p {
  margin: 0 0 1rem;
  font-size: clamp(1rem, 1.3vw, 1.0625rem);
  line-height: 1.85;
  max-width: 36em;
}

.page-about .prose p:last-child {
  margin-bottom: 0;
}

.page-about .about-quote {
  margin: 1.5rem 0 0;
  padding: 0.35rem 0 0.35rem 1.1rem;
  border-left: 4px solid var(--purple-mid);
  font-family: var(--font-display);
  font-size: clamp(1.05rem, 2.1vw, 1.3rem);
  line-height: 1.65;
  color: var(--purple);
}

/* ---------- 图 ---------- */
.page-about .about-figure {
  margin: 0 0 1.5rem;
  border: var(--rule) solid var(--ink);
}

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

.page-about .about-figure .media-frame__caption {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  color: var(--muted);
  padding: 0.6rem 0.8rem;
  background-color: var(--index-ivory);
  border-top: 1px solid var(--about-line-gold);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  position: relative;
  margin-top: 0.5rem;
  padding-left: 1.75rem;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 0.8rem;
  bottom: 0.8rem;
  width: 1.5px;
  background-image: linear-gradient(180deg, var(--gold), rgba(201, 162, 39, 0.2));
}

.page-about .about-stage {
  position: relative;
  padding-block: 1.1rem;
}

.page-about .about-stage::before {
  content: "";
  position: absolute;
  left: -1.75rem;
  top: 1.5rem;
  width: 9px;
  height: 9px;
  box-sizing: border-box;
  border: 2px solid var(--gold);
  border-radius: 50%;
  background-color: var(--ivory);
}

.page-about .about-stage__grid {
  display: grid;
  gap: 0.6rem;
}

.page-about .about-stage__code {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.1em;
  color: var(--gold);
  padding-bottom: 0.35rem;
  border-bottom: 1px solid var(--about-line-gold);
  display: inline-block;
}

.page-about .about-stage h3 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.1rem, 2.2vw, 1.35rem);
  line-height: 1.4;
  margin: 0.6rem 0 0.5rem;
  color: var(--ink);
}

.page-about .about-stage__body p {
  margin: 0;
  font-size: clamp(0.95rem, 1.25vw, 1.02rem);
  line-height: 1.85;
  max-width: 36em;
  color: var(--ink);
}

.page-about .about-stage__aside {
  margin: 0;
  padding-top: 0.5rem;
  border-top: 1px solid var(--about-line);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  line-height: 1.7;
  letter-spacing: 0.03em;
  color: var(--muted);
}

/* ---------- 结构剖面 ---------- */
.page-about .about-structure {
  position: relative;
  margin-block: clamp(1.5rem, 3vw, 2.5rem);
  padding-block: clamp(2.25rem, 5vw, 3.75rem);
  background: linear-gradient(160deg, var(--purple) 0%, #241340 58%, var(--ink) 100%);
  color: var(--ivory);
  border-block: var(--rule) solid var(--gold);
}

.page-about .about-structure .eyebrow {
  color: var(--gold-light);
}

.page-about .about-structure h2 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.5rem, 3.4vw, 2.3rem);
  line-height: 1.25;
  margin: 0.5rem 0 0;
  color: var(--ivory);
}

.page-about .about-structure__lead {
  margin: 1rem 0 0;
  max-width: 40em;
  font-size: clamp(0.98rem, 1.3vw, 1.05rem);
  line-height: 1.85;
  color: rgba(246, 241, 231, 0.8);
}

.page-about .about-structure__grid {
  display: grid;
  gap: clamp(1.5rem, 3vw, 2.25rem);
  margin-top: clamp(1.5rem, 3vw, 2.25rem);
}

.page-about .about-dir {
  border-top: 1px solid rgba(201, 162, 39, 0.5);
}

.page-about .about-dir__item {
  border-bottom: 1px solid rgba(201, 162, 39, 0.28);
}

.page-about .about-dir__summary {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  padding: 0.9rem 0.25rem 0.9rem 0;
  cursor: pointer;
  list-style: none;
  transition: background-color 160ms ease;
}

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

.page-about .about-dir__summary:hover,
.page-about .about-dir__summary:focus-visible {
  background-color: rgba(201, 162, 39, 0.08);
}

.page-about .about-dir__summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--gold-light);
}

.page-about .about-dir__item[open] .about-dir__summary::after {
  content: "−";
}

.page-about .about-dir__code {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.1em;
  color: var(--gold);
}

.page-about .about-dir__name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.02rem, 2vw, 1.18rem);
  color: var(--ivory);
}

.page-about .about-dir__count {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.04em;
  color: rgba(246, 241, 231, 0.55);
}

.page-about .about-dir__list {
  list-style: none;
  margin: 0;
  padding: 0 0 1rem 1.6rem;
  border-left: 1px solid rgba(201, 162, 39, 0.4);
  margin-left: 0.35rem;
}

.page-about .about-dir__list li {
  position: relative;
  padding: 0.3rem 0 0.3rem 0.9rem;
  font-size: 0.9rem;
  line-height: 1.7;
  color: rgba(246, 241, 231, 0.82);
}

.page-about .about-dir__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 1rem;
  width: 7px;
  height: 1px;
  background-color: rgba(201, 162, 39, 0.7);
}

.page-about .about-structure__aside {
  display: grid;
  gap: 1.25rem;
  align-content: start;
}

.page-about .about-structure__aside .about-figure {
  margin: 0;
  border-color: var(--gold);
}

.page-about .about-structure__aside .media-frame__caption {
  background-color: rgba(22, 18, 27, 0.55);
  color: rgba(246, 241, 231, 0.7);
}

.page-about .about-code-strip {
  border: var(--rule) solid var(--about-line-gold);
  padding: 1rem;
  background-color: rgba(22, 18, 27, 0.35);
}

.page-about .about-code-strip .mono-label {
  color: var(--gold-light);
  margin: 0 0 0.6rem;
}

.page-about .about-code-strip__value {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.4rem;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.86rem;
  letter-spacing: 0.06em;
  color: var(--ivory);
}

.page-about .about-code-strip__value i {
  font-style: normal;
  color: var(--gold);
}

.page-about .about-code-strip__hint {
  margin: 0.6rem 0 0;
  font-size: 0.8rem;
  line-height: 1.7;
  color: rgba(246, 241, 231, 0.66);
}

/* ---------- 末段窄幅 ---------- */
.page-about .about-tail {
  padding-block: clamp(2rem, 4vw, 3.5rem) clamp(3rem, 6vw, 5rem);
}

.page-about .about-tail .about-section + .about-section {
  border-top: 1px solid var(--about-line);
  margin-top: clamp(1.5rem, 3vw, 2rem);
  padding-top: clamp(1.5rem, 3vw, 2rem);
}

.page-about .about-team {
  display: grid;
  gap: 1rem;
  margin-top: 1.5rem;
}

.page-about .about-team__card {
  border-top: var(--rule) solid var(--prple, var(--purple-mid));
  border-top-color: var(--purple-mid);
  background-color: var(--index-ivory);
  padding: 1.1rem 1.1rem 1.25rem;
}

.page-about .about-team__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(1.75rem, 4vw, 2.2rem);
  line-height: 1;
  letter-spacing: 0.04em;
  color: var(--purple);
}

.page-about .about-team__num span {
  font-family: var(--font-body);
  font-size: 0.8rem;
  margin-left: 0.25rem;
  color: var(--muted);
}

.page-about .about-team__role {
  font-family: var(--font-display);
  font-size: 1.05rem;
  margin: 0.55rem 0 0.4rem;
  color: var(--ink);
}

.page-about .about-team__desc {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.75;
  color: #3c3446;
}

.page-about .about-legend {
  list-style: none;
  margin: 1.5rem 0;
  padding: 0;
  display: grid;
  gap: 0.5rem;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
}

.page-about .about-legend__item {
  display: grid;
  gap: 0.2rem;
  padding: 0.75rem 0.85rem;
  background-color: var(--celadon-light);
  border-left: 3px solid var(--celadon);
  transition: border-color 160ms ease, background-color 160ms ease;
}

.page-about .about-legend__item:hover,
.page-about .about-legend__item:focus-within {
  border-left-color: var(--gold);
  background-color: #e7efe9;
}

.page-about .about-legend__name {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  color: var(--celadon);
}

.page-about .about-legend__desc {
  font-size: 0.84rem;
  line-height: 1.65;
  color: #2b3b34;
}

.page-about .about-quality__list {
  list-style: none;
  margin: 1.25rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.9rem;
}

.page-about .about-quality__item {
  position: relative;
  padding-left: 1.1rem;
  font-size: clamp(0.95rem, 1.25vw, 1.02rem);
  line-height: 1.85;
  color: var(--ink);
  max-width: 40em;
}

.page-about .about-quality__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.75rem;
  width: 8px;
  height: 8px;
  border: 1.5px solid var(--gold);
  transform: rotate(45deg);
}

.page-about .about-quality__item strong {
  color: var(--purple);
}

.page-about .about-next {
  display: grid;
  gap: 1rem;
  margin-top: 1.5rem;
}

.page-about .about-next__card {
  display: grid;
  gap: 0.4rem;
  padding: 1.15rem 1.15rem 1.3rem;
  border: var(--rule) solid var(--ink);
  background-color: #fffdf8;
  text-decoration: none;
  color: var(--ink);
  transition: border-color 180ms ease, box-shadow 180ms ease, transform 180ms ease;
}

.page-about .about-next__card .mono-label {
  color: var(--celadon);
}

.page-about .about-next__card:hover,
.page-about .about-next__card:focus-visible {
  border-color: var(--purple-mid);
  box-shadow: 5px 5px 0 rgba(46, 27, 79, 0.16);
}

.page-about .about-next__link {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.05rem, 2vw, 1.2rem);
  line-height: 1.4;
  color: var(--purple);
}

.page-about .about-next__desc {
  font-size: 0.88rem;
  line-height: 1.7;
  color: #3c3446;
}

.page-about .about-next__more {
  margin: 1.25rem 0 0;
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-next__more a {
  color: var(--celadon);
  font-weight: 700;
  text-decoration: underline;
  text-decoration-color: rgba(47, 122, 99, 0.35);
  text-underline-offset: 3px;
}

.page-about .about-next__more a:hover {
  text-decoration-color: var(--celadon);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-team {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
  }

  .page-about .about-layout {
    grid-template-columns: minmax(0, 3fr) minmax(0, 9fr);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--bar-h) + 1.5rem);
    border-top: 0;
    border-left: var(--rule) solid var(--about-line-gold);
    padding: 0.25rem 0 0.25rem 1rem;
  }

  .page-about .about-rail__nav {
    flex-direction: column;
    gap: 0;
  }

  .page-about .about-rail__nav a {
    border-bottom: 1px solid rgba(107, 98, 116, 0.16);
    padding-block: 0.45rem;
  }

  .page-about .about-structure__grid {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
  }
}

@media (min-width: 1024px) {
  .page-about .about-stage__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 2fr);
    gap: 1.5rem;
    align-items: start;
  }

  .page-about .about-stage__aside {
    border-top: 0;
    border-left: 1px solid var(--about-line-gold);
    padding: 0.15rem 0 0 0.9rem;
  }

  .page-about .about-tail {
    max-width: 1080px;
    margin-inline: auto;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__nav a,
  .page-about .about-rail__nav a::before,
  .page-about .about-legend__item,
  .page-about .about-next__card,
  .page-about .about-dir__summary {
    transition: none;
  }
}
<<<END>>>

.page-about {
  --prple: currentColor;
}