.page-about {
  --about-gap: clamp(22px, 3.2vw, 48px);
  min-width: 0;
  overflow-x: clip;
  background: var(--ink);
}

.page-about .section {
  padding-block: clamp(40px, 6vw, 84px);
}

.page-about a:focus-visible,
.page-about summary:focus-visible,
.page-about button:focus-visible {
  outline: 2px solid var(--green);
  outline-offset: 4px;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: clamp(18px, 2.6vw, 32px);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--text-mute);
}

.page-about .crumb {
  color: var(--text-soft);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .2s ease, border-color .2s ease;
}

.page-about .crumb:hover {
  color: var(--green);
  border-bottom-color: currentColor;
}

.page-about .crumb-sep {
  color: var(--line-strong);
}

.page-about .crumb-current {
  color: var(--paper);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding-top: clamp(22px, 3.4vw, 44px);
  padding-bottom: clamp(32px, 5vw, 68px);
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(120% 90% at 82% 0%, rgba(28, 74, 87, .55), rgba(8, 34, 43, 0) 62%),
    linear-gradient(180deg, rgba(15, 53, 66, .45), rgba(8, 34, 43, 0) 72%);
}

.page-about .about-hero-grid {
  display: grid;
  gap: clamp(24px, 3.4vw, 48px);
  align-items: start;
}

.page-about .about-title {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-size: clamp(30px, 5.2vw, 64px);
  font-weight: 900;
  line-height: 1.08;
  letter-spacing: -.02em;
  color: var(--paper);
  overflow-wrap: anywhere;
}

.page-about .about-lede {
  margin: 0;
  max-width: 40ch;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.85;
  color: var(--text-soft);
}

.page-about .about-stats {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.page-about .about-stat {
  padding: 14px 15px;
  background: rgba(28, 74, 87, .55);
  border: 1px solid var(--line);
  border-left: 2px solid var(--indigo);
  border-radius: var(--radius);
}

.page-about .about-stat:nth-child(1) { border-left-color: var(--green); }
.page-about .about-stat:nth-child(2) { border-left-color: var(--indigo); }
.page-about .about-stat:nth-child(3) { border-left-color: var(--amber); }
.page-about .about-stat:nth-child(4) { border-left-color: var(--green); }

.page-about .stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(22px, 2.4vw, 28px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: .02em;
  color: var(--paper);
}

.page-about .stat-label {
  display: block;
  margin-top: 7px;
  font-size: 12.5px;
  line-height: 1.5;
  letter-spacing: .02em;
  color: var(--text-mute);
}

/* ---------- 编号 + 内容的分栏 ---------- */
.page-about .about-split {
  display: grid;
  gap: clamp(14px, 2vw, 26px);
}

.page-about .split-rail {
  display: flex;
  align-items: baseline;
  gap: 12px;
  font-family: var(--font-mono);
}

.page-about .split-num {
  font-size: clamp(24px, 2.8vw, 32px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: .02em;
  color: var(--indigo);
}

.page-about .split-label {
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--text-mute);
}

.page-about .about-h2 {
  margin: 0 0 18px;
  font-family: var(--font-display);
  font-size: clamp(22px, 3.1vw, 38px);
  font-weight: 800;
  line-height: 1.22;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .about-p {
  margin: 0 0 16px;
  max-width: 38ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--text-soft);
}

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

.page-about .about-inline-link {
  color: var(--green);
  text-decoration: none;
  border-bottom: 1px solid rgba(47, 208, 138, .45);
  transition: border-color .2s ease;
}

.page-about .about-inline-link:hover {
  border-bottom-color: var(--green);
}

.page-about .about-footnote {
  margin: clamp(24px, 3vw, 36px) 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--indigo);
  max-width: 46ch;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-mute);
}

/* ---------- 发展历程 ---------- */
.page-about .timeline {
  display: grid;
  gap: clamp(24px, 3.4vw, 48px);
  margin-top: clamp(24px, 3.4vw, 40px);
}

.page-about .timeline-rail {
  display: grid;
  gap: 16px;
  min-width: 0;
}

.page-about .timeline-figure {
  margin: 0;
  padding: 14px;
  background: rgba(28, 74, 87, .35);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.page-about .timeline-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border-radius: var(--radius);
}

.page-about .tl-nav-wrap {
  border-top: 1px solid var(--line);
  padding-top: 14px;
}

.page-about .tl-nav {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .tl-nav-link {
  display: inline-block;
  padding: 5px 9px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--text-soft);
  text-decoration: none;
  background: rgba(28, 74, 87, .45);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: color .2s ease, border-color .2s ease, background-color .2s ease;
}

.page-about .tl-nav-link:hover {
  color: var(--paper);
  border-color: var(--green);
  background: rgba(47, 208, 138, .12);
}

.page-about .tl-list {
  list-style: none;
  margin: 0;
  padding: 0;
  min-width: 0;
}

.page-about .tl-item {
  position: relative;
  padding: 0 0 clamp(26px, 3.4vw, 44px) clamp(38px, 6vw, 62px);
  scroll-margin-top: 110px;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 10px;
  bottom: 0;
  width: 1px;
  background: var(--line);
}

.page-about .tl-item:last-child {
  padding-bottom: 0;
}

.page-about .tl-item:last-child::before {
  display: none;
}

.page-about .tl-item::after {
  content: "";
  position: absolute;
  left: 0;
  top: 7px;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  background: var(--indigo);
  border: 1px solid var(--indigo);
  box-shadow: 0 0 0 4px var(--ink);
}

.page-about .tl-item--green::after {
  background: var(--green);
  border-color: var(--green);
}

.page-about .tl-item--amber::after {
  background: var(--amber);
  border-color: var(--amber);
}

.page-about .tl-num {
  display: block;
  margin-bottom: 7px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--text-mute);
}

.page-about .tl-title {
  margin: 0 0 9px;
  font-family: var(--font-display);
  font-size: clamp(18px, 2.1vw, 23px);
  font-weight: 800;
  line-height: 1.32;
  color: var(--paper);
}

.page-about .tl-text {
  margin: 0;
  max-width: 44ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--text-soft);
}

/* ---------- 团队 ---------- */
.page-about .team-figure {
  margin: clamp(22px, 3vw, 36px) 0 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--panel);
}

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

.page-about .team-cards {
  display: grid;
  gap: 16px;
  margin-top: clamp(18px, 2.6vw, 28px);
}

.page-about .team-card {
  display: flex;
  flex-direction: column;
  padding: 20px 18px 18px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-top: 3px solid var(--indigo);
  border-radius: var(--radius);
  transition: transform .28s ease, background-color .28s ease;
}

.page-about .team-card:nth-child(1) { border-top-color: var(--green); }
.page-about .team-card:nth-child(2) { border-top-color: var(--indigo); }
.page-about .team-card:nth-child(3) { border-top-color: var(--amber); }

.page-about .team-card:hover,
.page-about .team-card:focus-within {
  transform: translateY(-2px);
  background: var(--glass);
}

.page-about .team-tag {
  align-self: flex-start;
  padding: 3px 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--paper);
  background: var(--wine);
  border-radius: var(--radius);
}

.page-about .team-name {
  margin: 14px 0 10px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 800;
  line-height: 1.35;
  color: var(--paper);
}

.page-about .team-duty {
  margin: 0 0 16px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-soft);
}

.page-about .team-more {
  margin-top: auto;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
}

.page-about .team-more summary {
  cursor: pointer;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .04em;
  color: var(--green);
}

.page-about .team-more summary::-webkit-details-marker {
  display: none;
}

.page-about .team-more summary::before {
  content: "+";
  display: inline-block;
  width: 1em;
  color: var(--text-mute);
}

.page-about .team-more[open] summary::before {
  content: "–";
}

.page-about .team-more ul {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
  display: grid;
  gap: 7px;
}

.page-about .team-more li {
  position: relative;
  padding-left: 15px;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--text-soft);
}

.page-about .team-more li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .72em;
  width: 8px;
  height: 1px;
  background: var(--indigo);
}

/* ---------- 文档与索引 ---------- */
.page-about .doc-list {
  list-style: none;
  margin: clamp(20px, 3vw, 32px) 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .doc-item {
  display: grid;
  gap: 6px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .doc-key {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: .04em;
  color: var(--amber);
}

.page-about .doc-val {
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--text-soft);
}

/* ---------- 服务范围 ---------- */
.page-about .section--coverage {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(180deg, rgba(15, 53, 66, .9), rgba(8, 34, 43, .2)),
    var(--ink);
}

.page-about .coverage {
  display: grid;
  gap: clamp(22px, 3.2vw, 44px);
  align-items: start;
  margin-top: clamp(20px, 3vw, 32px);
}

.page-about .coverage-copy {
  min-width: 0;
}

.page-about .coverage-note {
  margin: 22px 0 0;
  padding: 14px 16px;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.8;
  letter-spacing: .02em;
  color: var(--paper);
  background: rgba(28, 74, 87, .6);
  border-left: 2px solid var(--amber);
  border-radius: var(--radius);
  overflow-wrap: anywhere;
}

.page-about .coverage-figure {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--panel);
}

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

/* ---------- 收束 ---------- */
.page-about .about-closing {
  padding-bottom: clamp(40px, 6vw, 72px);
}

.page-about .about-closing-band {
  display: grid;
  gap: 22px;
  padding: clamp(24px, 3.6vw, 44px);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  background:
    linear-gradient(118deg, rgba(47, 208, 138, .13), rgba(8, 34, 43, 0) 48%),
    linear-gradient(300deg, rgba(122, 46, 58, .22), rgba(8, 34, 43, 0) 58%),
    var(--panel);
}

.page-about .closing-text {
  margin: 12px 0 0;
  max-width: 44ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--text-soft);
}

.page-about .closing-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 自适应 ---------- */
@media (min-width: 760px) {
  .page-about .doc-item {
    grid-template-columns: 148px minmax(0, 1fr);
    align-items: baseline;
    gap: 24px;
    padding: 18px 0;
  }
}

@media (min-width: 820px) {
  .page-about .team-cards {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-split {
    grid-template-columns: 150px minmax(0, 1fr);
    gap: clamp(20px, 2.8vw, 40px);
  }

  .page-about .split-rail {
    flex-direction: column;
    gap: 10px;
  }

  .page-about .coverage {
    grid-template-columns: minmax(0, 6fr) minmax(0, 5fr);
  }

  .page-about .about-closing-band {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }
}

@media (min-width: 960px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }

  .page-about .timeline {
    grid-template-columns: minmax(0, 3.2fr) minmax(0, 7fr);
    align-items: start;
  }
}

@media (max-width: 480px) {
  .page-about .about-stats {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .closing-actions .btn {
    flex: 1 1 100%;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .team-card,
  .page-about .tl-nav-link {
    transition: none;
  }

  .page-about .team-card:hover,
  .page-about .team-card:focus-within {
    transform: none;
  }
}