.page-about {
  --about-serif: Georgia, "Songti SC", "SimSun", "Times New Roman", serif;
  --about-clip: 14px;
  background: var(--ink);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding-block: 1.5rem 2rem;
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(92% 130% at 108% -12%, rgba(57, 242, 176, 0.13), transparent 62%),
    linear-gradient(174deg, var(--moss) 0%, var(--ink) 74%);
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: repeating-linear-gradient(118deg, rgba(57, 242, 176, 0.055) 0 1px, transparent 1px 48px);
}

.page-about .about-hero > .shell {
  position: relative;
  z-index: 1;
}

.page-about .breadcrumbs {
  margin-bottom: 1.5rem;
  font-size: 0.75rem;
}

.page-about .breadcrumbs a {
  color: var(--text-dim);
  text-decoration: none;
  transition: color 0.2s var(--ease);
}

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

.page-about .breadcrumbs li[aria-current="page"] {
  color: var(--amber);
}

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

.page-about .about-hero__kicker {
  margin: 0;
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--mint);
}

.page-about .about-hero h1 {
  margin: 0.7rem 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-stretch: condensed;
  font-size: clamp(1.85rem, 7.6vw, 3.5rem);
  line-height: 1.04;
  letter-spacing: -0.028em;
  color: var(--paper);
  max-width: 19ch;
}

.page-about .about-hero__intro {
  margin: 1.1rem 0 0;
  max-width: 54ch;
  font-size: 0.94rem;
  line-height: 1.85;
  color: var(--text-dim);
}

.page-about .about-hero__intro strong {
  color: var(--paper);
  font-weight: 700;
}

.page-about .about-steps__label {
  margin: 0 0 0.75rem;
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  color: var(--text-faint);
}

.page-about .about-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.6rem;
}

.page-about .about-steps li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  grid-template-areas:
    "n t"
    "n d";
  align-items: center;
  gap: 0.1rem 0.85rem;
  padding: 0.7rem 0.9rem 0.75rem 0.95rem;
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 2px solid var(--amber);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%);
}

.page-about .about-steps__num {
  grid-area: n;
  font-size: 1.5rem;
  line-height: 1;
  color: var(--amber);
  letter-spacing: 0.02em;
}

.page-about .about-steps__title {
  grid-area: t;
  font-family: var(--font-display);
  font-size: 0.92rem;
  color: var(--paper);
  letter-spacing: 0.01em;
}

.page-about .about-steps__desc {
  grid-area: d;
  font-size: 0.8rem;
  line-height: 1.65;
  color: var(--text-dim);
}

.page-about .about-hero__stamp {
  margin: 1.5rem 0 0;
  padding-top: 0.85rem;
  border-top: 1px solid var(--line);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--text-faint);
}

/* ---------- 主区骨架 ---------- */
.page-about .about-body {
  display: grid;
  gap: 1.75rem;
  padding-block: 1.75rem 3rem;
}

.page-about .about-rail__label {
  margin: 0 0 0.6rem;
  font-size: 0.68rem;
  letter-spacing: 0.18em;
  color: var(--text-faint);
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0 0 0.35rem;
  display: flex;
  gap: 0.4rem;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.page-about .about-rail__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-rail__list > li {
  flex: 0 0 auto;
}

.page-about .about-rail__link {
  display: block;
  padding: 0.45rem 0.8rem;
  font-size: 0.8rem;
  white-space: nowrap;
  color: var(--text-dim);
  text-decoration: none;
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 2px solid var(--line);
  transition: color 0.22s var(--ease), border-color 0.22s var(--ease), background 0.22s var(--ease);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--mint-soft);
  border-left-color: var(--mint);
}

.page-about .about-rail__link[data-active="true"] {
  color: var(--amber);
  border-color: rgba(255, 178, 74, 0.45);
  border-left-color: var(--amber);
  background: rgba(255, 178, 74, 0.07);
}

/* ---------- 章节通用 ---------- */
.page-about .about-sec {
  padding-block: 2rem;
}

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

.page-about .about-flow > .about-sec:first-child {
  padding-top: 0.5rem;
}

.page-about .about-sec h2 {
  margin: 0.45rem 0 1rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-stretch: condensed;
  font-size: clamp(1.45rem, 5vw, 2.3rem);
  line-height: 1.12;
  letter-spacing: -0.015em;
  color: var(--paper);
  max-width: 24ch;
}

.page-about .about-sec__body p {
  margin: 0 0 0.95rem;
  font-size: 0.92rem;
  line-height: 1.86;
  color: var(--text-dim);
}

.page-about .about-sec__lede {
  margin: -0.35rem 0 1.25rem;
  font-family: var(--about-serif);
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--text-faint);
}

.page-about .about-pull {
  margin: 1.35rem 0;
  padding: 0.15rem 0 0.15rem 1rem;
  border-left: 2px solid var(--mint);
  font-family: var(--about-serif);
  font-size: clamp(1.05rem, 3.6vw, 1.4rem);
  line-height: 1.6;
  color: var(--mint-soft);
}

.page-about .about-inline-links {
  margin: 1.1rem 0 0;
  font-size: 0.84rem;
  line-height: 1.7;
  color: var(--text-faint);
}

.page-about .about-inline-links a {
  color: var(--mint);
  text-decoration: none;
  border-bottom: 1px solid rgba(57, 242, 176, 0.35);
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-inline-links a:hover,
.page-about .about-inline-links a:focus-visible {
  color: var(--mint-soft);
  border-bottom-color: var(--mint-soft);
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 1.5rem 0 0;
  padding: 0.4rem;
  background: var(--panel);
  border: 1px solid var(--line);
  clip-path: polygon(0 0, calc(100% - var(--about-clip)) 0, 100% var(--about-clip), 100% 100%, 0 100%);
}

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

.page-about .about-figure .media__caption {
  display: block;
  padding: 0.55rem 0.5rem 0.2rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.04em;
  color: var(--text-faint);
}

/* ---------- 编号方法 ---------- */
.page-about .about-split {
  display: grid;
  gap: 1.75rem;
}

.page-about .about-split__main p {
  margin: 0 0 1rem;
  font-size: 0.92rem;
  line-height: 1.86;
  color: var(--text-dim);
}

.page-about .about-index-list {
  list-style: none;
  margin: 1.35rem 0 1.1rem;
  padding: 0;
  display: grid;
  gap: 0.45rem;
}

.page-about .about-index-list li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.2rem 0.75rem;
  padding: 0.7rem 0.85rem;
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 2px solid var(--mint);
  transition: border-left-color 0.22s var(--ease), background 0.22s var(--ease);
}

.page-about .about-index-list li:hover {
  border-left-color: var(--amber);
  background: #18211e;
}

.page-about .about-index-list__num {
  font-size: 1.05rem;
  color: var(--amber);
  letter-spacing: 0.02em;
}

.page-about .about-index-list__name {
  font-family: var(--font-display);
  font-size: 0.95rem;
  color: var(--paper);
  letter-spacing: 0.01em;
}

.page-about .about-index-list__desc {
  flex: 1 1 100%;
  font-size: 0.82rem;
  line-height: 1.65;
  color: var(--text-dim);
}

.page-about .about-figure--tall {
  margin-top: 0;
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 1.4rem;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 0.34rem;
  top: 0.5rem;
  bottom: 0.6rem;
  width: 1px;
  background: linear-gradient(180deg, var(--mint) 0%, var(--amber) 58%, var(--line) 100%);
}

.page-about .about-timeline__item {
  position: relative;
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -1.26rem;
  top: 1.05rem;
  width: 0.5rem;
  height: 0.5rem;
  background: var(--ink);
  border: 1px solid var(--mint);
  transform: rotate(45deg);
  z-index: 1;
}

.page-about .about-stage {
  margin-bottom: 0.5rem;
  background: var(--panel);
  border: 1px solid var(--line);
  transition: border-color 0.22s var(--ease);
}

.page-about .about-stage[open] {
  border-color: rgba(57, 242, 176, 0.55);
}

.page-about .about-stage__sum {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 0.9rem;
  cursor: pointer;
  list-style: none;
  outline-offset: -2px;
}

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

.page-about .about-stage__sum::marker {
  content: "";
}

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

.page-about .about-stage__year {
  flex: 0 0 auto;
  font-size: 1.05rem;
  letter-spacing: 0.05em;
  color: var(--amber);
}

.page-about .about-stage__title {
  flex: 1 1 auto;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.95rem;
  letter-spacing: 0.01em;
  color: var(--paper);
}

.page-about .about-stage__more {
  flex: 0 0 auto;
  width: 1.4rem;
  height: 1.4rem;
  display: grid;
  place-items: center;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--mint);
}

.page-about .about-stage__more::after {
  content: "+";
}

.page-about .about-stage[open] .about-stage__more::after {
  content: "−";
}

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

.page-about .about-stage__body p {
  margin: 0.75rem 0 0;
  font-size: 0.88rem;
  line-height: 1.78;
  color: var(--text-dim);
}

/* ---------- 内容协作 ---------- */
.page-about .about-team {
  padding: 1.5rem 1.1rem 1.6rem;
  background: linear-gradient(158deg, var(--moss) 0%, var(--panel) 62%);
  border: 1px solid var(--line);
  clip-path: polygon(0 0, calc(100% - 22px) 0, 100% 22px, 100% 100%, 0 100%);
}

.page-about .about-team__lead h2 {
  margin: 0.45rem 0 0.9rem;
}

.page-about .about-team__lead p {
  margin: 0;
  max-width: 56ch;
  font-size: 0.92rem;
  line-height: 1.86;
  color: var(--text-dim);
}

.page-about .about-team__stats {
  list-style: none;
  margin: 1.35rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.55rem;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.page-about .about-team__stats li {
  padding: 0.75rem 0.8rem;
  border: 1px solid var(--line);
  border-top: 2px solid var(--mint);
  background: rgba(10, 14, 13, 0.55);
}

.page-about .about-team__num {
  display: block;
  font-size: clamp(1.6rem, 6.5vw, 2.3rem);
  line-height: 1;
  color: var(--mint);
  letter-spacing: 0.01em;
}

.page-about .about-team__cap {
  display: block;
  margin-top: 0.45rem;
  font-size: 0.78rem;
  line-height: 1.6;
  color: var(--text-dim);
}

.page-about .about-team__note {
  margin: 1.15rem 0 0;
  padding-top: 0.95rem;
  border-top: 1px dashed var(--line);
  font-size: 0.86rem;
  line-height: 1.78;
  color: var(--text-faint);
}

/* ---------- 服务与联系 ---------- */
.page-about .about-service {
  position: relative;
  overflow: hidden;
  background: var(--panel);
  border: 1px solid var(--line);
}

.page-about .about-service__bg {
  position: relative;
  margin: 0;
}

.page-about .about-service__bg img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: 170px;
  object-fit: cover;
}

.page-about .about-service__bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(10, 14, 13, 0.12) 0%, var(--panel) 94%);
}

.page-about .about-service__content {
  position: relative;
  z-index: 1;
  padding: 1.25rem 1.1rem 1.5rem;
}

.page-about .about-service__content h2 {
  margin: 0.45rem 0 0.9rem;
}

.page-about .about-service__content > p {
  margin: 0;
  max-width: 56ch;
  font-size: 0.92rem;
  line-height: 1.86;
  color: var(--text-dim);
}

.page-about .about-service__list {
  list-style: none;
  margin: 1.2rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.45rem;
}

.page-about .about-service__list li {
  display: grid;
  grid-template-columns: 3.1rem minmax(0, 1fr);
  gap: 0.7rem;
  align-items: baseline;
  padding: 0.65rem 0.75rem;
  background: rgba(10, 14, 13, 0.62);
  border: 1px solid var(--line);
}

.page-about .about-service__k {
  font-size: 0.74rem;
  letter-spacing: 0.1em;
  color: var(--amber);
}

.page-about .about-service__v {
  font-size: 0.85rem;
  line-height: 1.7;
  color: var(--text-dim);
  word-break: break-word;
}

.page-about .about-service__v a {
  color: var(--mint);
  text-decoration: none;
  border-bottom: 1px solid rgba(57, 242, 176, 0.35);
}

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

.page-about .about-service__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: 1.25rem;
}

/* ---------- 中屏 ---------- */
@media (min-width: 640px) {
  .page-about .about-hero {
    padding-block: 2rem 2.5rem;
  }

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

  .page-about .about-steps li {
    grid-template-areas:
      "n"
      "t"
      "d";
    grid-template-columns: minmax(0, 1fr);
    align-items: start;
    gap: 0.35rem;
  }

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

  .page-about .about-service__bg img {
    height: 220px;
  }
}

/* ---------- 宽屏 ---------- */
@media (min-width: 900px) {
  .page-about .about-hero {
    padding-block: 2.5rem 3rem;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.18fr) minmax(0, 0.82fr);
    gap: 3rem;
    align-items: start;
  }

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

  .page-about .about-body {
    grid-template-columns: 176px minmax(0, 1fr);
    gap: 3.25rem;
    padding-block: 3rem 5rem;
  }

  .page-about .about-rail {
    position: sticky;
    top: 6.5rem;
    align-self: start;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-rail__list > li + li {
    margin-top: -1px;
  }

  .page-about .about-rail__link {
    position: relative;
    padding: 0.62rem 0.8rem;
  }

  .page-about .about-rail__link::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: -1px;
    width: 0;
    height: 1px;
    background: var(--mint);
    transition: width 0.28s var(--ease);
  }

  .page-about .about-rail__link:hover::after,
  .page-about .about-rail__link:focus-visible::after {
    width: 100%;
  }

  .page-about .about-rail__link[data-active="true"]::after {
    width: 100%;
    background: var(--amber);
  }

  .page-about .about-sec {
    padding-block: 3rem;
  }

  .page-about .about-split {
    grid-template-columns: minmax(0, 1.32fr) minmax(0, 0.68fr);
    gap: 2.5rem;
    align-items: start;
  }

  .page-about .about-team {
    padding: 2.1rem 2rem 2.2rem;
  }

  .page-about .about-service {
    display: grid;
    grid-template-columns: minmax(0, 0.82fr) minmax(0, 1.18fr);
  }

  .page-about .about-service__bg img {
    height: 100%;
    min-height: 380px;
  }

  .page-about .about-service__bg::after {
    background: linear-gradient(90deg, rgba(10, 14, 13, 0.05) 0%, var(--panel) 96%);
  }

  .page-about .about-service__content {
    padding: 2.2rem 2rem 2.4rem;
  }
}

/* ---------- 宽内容区 ---------- */
@media (min-width: 1120px) {
  .page-about .about-sec__body {
    max-width: 62ch;
  }

  .page-about .about-figure {
    margin-top: 1.9rem;
  }
}

/* ---------- 减少动态 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .about-rail__link::after,
  .page-about .about-stage,
  .page-about .about-index-list li {
    transition: none;
  }
}
<<<END>>>