.page-about {
  --about-rail: 200px;
  --about-gap: 44px;
  --zone: var(--sea);
  background: var(--salt);
  color: var(--ink);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: 56px 0 48px;
  background: linear-gradient(160deg, var(--deep) 0%, var(--ink) 58%, #04121f 100%);
  color: var(--salt);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(115deg, rgba(159, 196, 220, .09) 0 1px, transparent 1px 72px),
    repeating-linear-gradient(65deg, rgba(159, 196, 220, .06) 0 1px, transparent 1px 104px);
}

.page-about .about-hero-inner {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 34px;
}

.page-about .about-hero-copy .eyebrow {
  color: var(--mist);
}

.page-about .hero-title {
  margin: 14px 0 16px;
  font-size: clamp(30px, 5.2vw, 46px);
  line-height: 1.18;
  letter-spacing: -.01em;
  font-weight: 900;
  color: #fff;
}

.page-about .hero-lede {
  max-width: 56ch;
  margin: 0 0 26px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--mist);
}

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

.page-about .hero-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: rgba(159, 196, 220, .22);
  border: 1px solid rgba(159, 196, 220, .22);
  border-radius: var(--cut);
  overflow: hidden;
}

.page-about .hero-stat {
  padding: 16px 15px;
  background: rgba(6, 26, 46, .72);
}

.page-about .hero-stat b {
  display: block;
  font-size: 26px;
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -.01em;
  font-variant-numeric: tabular-nums;
  color: #fff;
}

.page-about .hero-stat span {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--mist);
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumbs {
  padding: 18px 0 0;
}

/* ---------- 双栏骨架 ---------- */
.page-about .about-layout {
  display: grid;
  gap: 26px;
  padding: 14px 0 72px;
}

.page-about .about-rail {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding: 4px 0 10px;
  scrollbar-width: none;
}

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

.page-about .rail-label {
  display: none;
}

.page-about .rail-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  flex: 0 0 auto;
  padding: 9px 15px;
  border-radius: var(--pill);
  border: 1px solid rgba(11, 44, 74, .12);
  background: var(--panel);
  color: var(--deep);
  font-size: 14px;
  font-weight: 500;
  line-height: 1.3;
  text-decoration: none;
  white-space: nowrap;
  transition: background var(--t-fast) var(--ease),
              color var(--t-fast) var(--ease),
              border-color var(--t-fast) var(--ease);
}

.page-about .rail-link:hover,
.page-about .rail-link:focus-visible {
  background: var(--brand);
  border-color: var(--brand);
  color: #fff;
}

.page-about .rail-link:focus-visible {
  outline: 2px solid var(--coral);
  outline-offset: 2px;
}

.page-about .rail-num {
  font-size: 11px;
  font-weight: 900;
  letter-spacing: .08em;
  font-variant-numeric: tabular-nums;
  color: var(--sea);
}

.page-about .rail-link:hover .rail-num,
.page-about .rail-link:focus-visible .rail-num {
  color: var(--coral-soft);
}

/* ---------- 内容流 ---------- */
.page-about .about-flow > * + * {
  margin-top: 52px;
}

.page-about .z-sea { --zone: var(--sea); }
.page-about .z-coral { --zone: var(--coral); }
.page-about .z-jade { --zone: var(--jade); }

.page-about .flow-block {
  position: relative;
  padding-top: 22px;
}

.page-about .flow-block::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 52px;
  height: 4px;
  border-radius: 2px;
  background: var(--zone);
}

.page-about .flow-kicker {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 10px;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .16em;
  color: var(--zone);
}

.page-about .flow-kicker::after {
  content: "";
  flex: 0 0 auto;
  width: 26px;
  height: 1px;
  background: var(--zone);
  opacity: .55;
  transform: rotate(-12deg);
}

.page-about .flow-title {
  margin: 0 0 14px;
  font-size: clamp(23px, 3.4vw, 31px);
  line-height: 1.3;
  letter-spacing: -.01em;
  font-weight: 900;
  color: var(--ink);
}

.page-about .flow-lede {
  max-width: 62ch;
  margin: 0 0 26px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--slate);
}

.page-about .flow-tail {
  margin: 22px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--slate);
}

.page-about .flow-tail a {
  color: var(--brand);
  font-weight: 500;
}

/* ---------- 01 我们做什么 ---------- */
.page-about .what-grid {
  display: grid;
  gap: 14px;
}

.page-about .what-card {
  position: relative;
  padding: 22px 20px 22px 24px;
  background: var(--panel);
  border: 1px solid rgba(11, 44, 74, .08);
  border-radius: var(--cut);
  box-shadow: 0 14px 30px -24px rgba(6, 26, 46, .55);
}

.page-about .what-card::before {
  content: "";
  position: absolute;
  left: 0;
  top: 20px;
  bottom: 20px;
  width: 4px;
  border-radius: 0 2px 2px 0;
  background: var(--zone);
}

.page-about .what-card h3 {
  margin: 0 0 10px;
  font-size: 18px;
  line-height: 1.4;
  font-weight: 700;
  color: var(--deep);
}

.page-about .what-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--slate);
}

.page-about .what-more {
  margin-top: 12px;
}

.page-about .link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 14px;
  font-weight: 700;
  color: var(--coral);
  text-decoration: none;
}

.page-about .link-arrow::after {
  content: "";
  width: 7px;
  height: 7px;
  border-top: 2px solid currentColor;
  border-right: 2px solid currentColor;
  transform: rotate(45deg);
  transition: transform var(--t-fast) var(--ease);
}

.page-about .link-arrow:hover::after,
.page-about .link-arrow:focus-visible::after {
  transform: rotate(45deg) translate(2px, -2px);
}

/* ---------- 02 迭代路线 ---------- */
.page-about .roadmap-figure {
  margin-bottom: 34px;
}

.page-about .timeline {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 26px;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--sea) 0%, var(--coral) 52%, var(--jade) 100%);
  opacity: .55;
}

.page-about .timeline-item {
  position: relative;
  padding: 0 0 26px;
}

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

.page-about .timeline-item::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 6px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--panel);
  border: 2px solid var(--zone);
  transform: translateX(2px);
}

.page-about .timeline-week {
  display: inline-block;
  margin-bottom: 8px;
  padding: 3px 10px;
  border-radius: var(--pill);
  background: var(--salt);
  border: 1px solid rgba(11, 44, 74, .1);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .06em;
  font-variant-numeric: tabular-nums;
  color: var(--deep);
}

.page-about .timeline-title {
  margin: 0 0 8px;
  font-size: 17px;
  line-height: 1.45;
  font-weight: 700;
  color: var(--ink);
}

.page-about .timeline-text {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--slate);
}

/* ---------- 03 团队与分工 ---------- */
.page-about .team-mosaic {
  display: flex;
  flex-direction: column;
  gap: 10px;
  height: 420px;
  margin-bottom: 30px;
}

.page-about .team-block {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 10px;
  padding: 18px;
  border-radius: var(--cut);
  color: #fff;
  overflow: hidden;
  transition: transform var(--t-block) var(--ease), filter var(--t-block) var(--ease);
}

.page-about .team-block:hover {
  transform: translateY(-3px);
  filter: brightness(1.06);
}

.page-about .team-block--ops {
  flex: 18 1 0;
  background: linear-gradient(150deg, var(--brand), var(--deep));
}

.page-about .team-block--design {
  flex: 15 1 0;
  background: linear-gradient(150deg, var(--sea), var(--brand));
}

.page-about .team-block--content {
  flex: 9 1 0;
  background: linear-gradient(150deg, var(--jade), #12705c);
}

.page-about .team-block h3 {
  margin: 0 0 6px;
  font-size: 16px;
  font-weight: 700;
  color: #fff;
}

.page-about .team-block p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: rgba(255, 255, 255, .84);
}

.page-about .team-num {
  display: block;
  font-size: 28px;
  font-weight: 900;
  line-height: 1;
  letter-spacing: -.01em;
  font-variant-numeric: tabular-nums;
  color: rgba(255, 255, 255, .96);
}

.page-about .team-lower {
  display: grid;
  gap: 24px;
}

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

.page-about .team-cadence h3 {
  margin: 0 0 12px;
  font-size: 18px;
  font-weight: 700;
  color: var(--deep);
}

.page-about .team-cadence ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .team-cadence li {
  position: relative;
  padding: 9px 0 9px 22px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--slate);
  border-bottom: 1px solid rgba(11, 44, 74, .08);
}

.page-about .team-cadence li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 18px;
  width: 10px;
  height: 2px;
  border-radius: 1px;
  background: var(--jade);
  transform: rotate(-12deg);
}

.page-about .cadence-note {
  margin: 16px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--slate);
}

.page-about .cadence-note a {
  color: var(--jade);
  font-weight: 700;
}

/* ---------- 04 覆盖与生态 ---------- */
.page-about .coverage-grid {
  display: grid;
  gap: 26px;
}

.page-about .coverage-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 12px;
}

.page-about .coverage-stats li {
  padding: 16px 14px;
  background: var(--panel);
  border: 1px solid rgba(255, 122, 77, .26);
  border-left: 4px solid var(--coral);
  border-radius: var(--cut);
}

.page-about .coverage-stats b {
  display: block;
  font-size: 26px;
  font-weight: 900;
  line-height: 1.1;
  font-variant-numeric: tabular-nums;
  color: var(--deep);
}

.page-about .coverage-stats span {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--slate);
}

.page-about .coverage-text {
  margin: 20px 0 18px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--slate);
}

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

.page-about .coverage-figure {
  margin: 0;
}

/* ---------- 05 做事准则 ---------- */
.page-about .principles {
  display: grid;
  gap: 10px;
}

.page-about .principle {
  background: var(--panel);
  border: 1px solid rgba(11, 44, 74, .08);
  border-left: 4px solid var(--jade);
  border-radius: var(--cut);
  overflow: hidden;
  transition: box-shadow var(--t-fast) var(--ease);
}

.page-about .principle[open] {
  box-shadow: 0 16px 34px -26px rgba(6, 26, 46, .6);
}

.page-about .principle summary {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 15px 16px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .principle-num {
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--jade-soft);
  color: #0d6a55;
  font-size: 12px;
  font-weight: 900;
  font-variant-numeric: tabular-nums;
}

.page-about .principle-name {
  flex: 0 0 auto;
  font-size: 16px;
  font-weight: 700;
  color: var(--deep);
}

.page-about .principle-sub {
  display: none;
  font-size: 13px;
  line-height: 1.5;
  color: var(--slate);
}

.page-about .principle summary::after {
  content: "+";
  flex: 0 0 auto;
  margin-left: auto;
  display: grid;
  place-items: center;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--salt);
  color: var(--brand);
  font-size: 15px;
  font-weight: 700;
  line-height: 1;
}

.page-about .principle[open] summary::after {
  content: "−";
  background: var(--jade);
  color: #fff;
}

.page-about .principle p {
  margin: 0;
  padding: 0 18px 18px 54px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--slate);
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  display: grid;
  gap: 22px;
  padding: 30px 24px;
  background: linear-gradient(140deg, var(--deep), var(--brand));
  color: var(--salt);
  border-radius: var(--cut);
  position: relative;
  overflow: hidden;
}

.page-about .about-cta::after {
  content: "";
  position: absolute;
  right: -40px;
  bottom: -60px;
  width: 200px;
  height: 200px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255, 122, 77, .35), transparent 68%);
  pointer-events: none;
}

.page-about .cta-copy h2 {
  margin: 0 0 10px;
  font-size: clamp(21px, 3vw, 26px);
  line-height: 1.35;
  font-weight: 900;
  color: #fff;
}

.page-about .cta-copy p {
  margin: 0;
  max-width: 56ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .cta-actions {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .cta-actions .btn-line {
  color: var(--salt);
  border-color: rgba(242, 247, 251, .5);
}

.page-about .cta-actions .btn-line:hover,
.page-about .cta-actions .btn-line:focus-visible {
  background: rgba(242, 247, 251, .14);
  border-color: var(--salt);
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero {
    padding: 72px 0 60px;
  }

  .page-about .what-grid {
    grid-template-columns: repeat(6, minmax(0, 1fr));
    gap: 16px;
  }

  .page-about .what-card:nth-child(1) {
    grid-column: span 6;
  }

  .page-about .what-card:nth-child(2),
  .page-about .what-card:nth-child(3) {
    grid-column: span 3;
  }

  .page-about .team-mosaic {
    flex-direction: row;
    height: 300px;
  }

  .page-about .principle-sub {
    display: block;
    max-width: 44ch;
    text-align: right;
  }

  .page-about .principle p {
    padding-left: 56px;
    max-width: 78ch;
  }

  .page-about .timeline {
    padding-left: 34px;
  }

  .page-about .timeline-item::before {
    left: -34px;
    top: 7px;
  }

  .page-about .timeline::before {
    left: 7px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero-inner {
    grid-template-columns: minmax(0, 1.45fr) minmax(280px, .8fr);
    align-items: end;
    gap: 48px;
  }

  .page-about .team-lower {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    align-items: center;
    gap: 30px;
  }

  .page-about .team-figure {
    margin-top: -22px;
  }

  .page-about .coverage-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, .85fr);
    align-items: start;
    gap: 34px;
  }

  .page-about .coverage-figure {
    margin-top: 8px;
  }
}

@media (min-width: 1024px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: var(--about-gap);
    align-items: start;
    padding-top: 20px;
  }

  .page-about .about-rail {
    position: sticky;
    top: 104px;
    flex-direction: column;
    gap: 6px;
    overflow: visible;
    padding: 0;
  }

  .page-about .rail-label {
    display: block;
    margin-bottom: 6px;
    font-size: 12px;
    font-weight: 700;
    letter-spacing: .18em;
    color: var(--slate);
  }

  .page-about .rail-link {
    width: 100%;
    white-space: normal;
    border-radius: 0 var(--pill) var(--pill) 0;
  }

  .page-about .about-flow > * + * {
    margin-top: 64px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .rail-link,
  .page-about .what-card,
  .page-about .team-block,
  .page-about .principle,
  .page-about .link-arrow::after {
    transition: none;
  }

  .page-about .team-block:hover {
    transform: none;
  }
}