.page-about {
  --about-rail-w: 84px;
  --about-tint: rgba(14, 42, 71, 0.04);
  background: var(--paper);
  color: var(--ink);
  overflow-x: clip;
}

.page-about .about-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.06em;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-block: 20px 40px;
}

.page-about .about-hero__inner {
  display: grid;
  gap: 18px;
}

.page-about .about-hero__stamp {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
  margin: 0;
}

.page-about .about-hero__domain {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--blue-deep);
  opacity: 0.7;
}

.page-about .about-hero__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(34px, 8.4vw, 76px);
  line-height: 1.06;
  letter-spacing: 0.02em;
  color: var(--blue-deep);
}

.page-about .about-hero__lower {
  display: grid;
  gap: 24px;
  padding-top: 8px;
}

.page-about .about-hero__lede {
  margin: 0;
  max-width: 34em;
  font-size: 17px;
  line-height: 1.75;
  color: var(--ink);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px 18px;
  margin: 0;
  padding: 18px 0 0;
  border-top: 1px solid var(--line-ink);
}

.page-about .about-fact dt {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--blue-deep);
  opacity: 0.65;
}

.page-about .about-fact dd {
  margin: 4px 0 0;
  font-size: 26px;
  font-weight: 500;
  color: var(--blue-deep);
}

.page-about .about-fact dd span {
  margin-left: 3px;
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 400;
  letter-spacing: 0.08em;
  opacity: 0.7;
}

/* ---------- 主体骨架 ---------- */
.page-about .about-body {
  padding-block: 8px 32px;
}

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

.page-about .about-flow {
  display: block;
}

.page-about .about-sec {
  padding-block: clamp(44px, 7vw, 88px);
}

.page-about .about-sec--tight .about-prose {
  max-width: var(--read-width);
}

.page-about .about-sec--right {
  margin-left: auto;
}

.page-about .section-head {
  margin-bottom: 26px;
}

.page-about .section-head__index {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.16em;
  color: var(--coral);
}

.page-about .section-head__title {
  margin: 6px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(24px, 4.6vw, 40px);
  line-height: 1.18;
  letter-spacing: 0.02em;
  color: var(--blue-deep);
}

.page-about .section-head__note {
  margin: 10px 0 0;
  max-width: 30em;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink);
  opacity: 0.72;
}

.page-about .about-prose {
  display: grid;
  gap: 14px;
}

.page-about .about-prose p {
  margin: 0;
  font-size: 17px;
  line-height: 1.78;
  max-width: 34em;
}

.page-about .about-prose--after {
  margin-top: 22px;
  padding-left: 16px;
  border-left: 2px solid var(--sand);
}

.page-about .about-prose--after p {
  font-size: 15px;
  opacity: 0.82;
}

.page-about .annotation {
  margin: 22px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--blue-deep);
  opacity: 0.8;
}

.page-about .annotation a {
  color: var(--blue-deep);
  border-bottom: 1px solid var(--coral);
  text-decoration: none;
}

/* ---------- 数据条 ---------- */
.page-about .about-stats {
  display: grid;
  gap: 1px;
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
  background: var(--line-ink);
}

.page-about .about-stat {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 16px 18px;
  background: var(--paper);
}

.page-about .about-stat__num {
  min-width: 4.4em;
  font-size: 28px;
  font-weight: 300;
  color: var(--blue-deep);
}

.page-about .about-stat__num em {
  margin-left: 2px;
  font-family: var(--font-body);
  font-style: normal;
  font-size: 12px;
  letter-spacing: 0.06em;
  opacity: 0.7;
}

.page-about .about-stat__label {
  font-size: 14px;
  letter-spacing: 0.04em;
  color: var(--ink);
  opacity: 0.78;
}

/* ---------- 三块入口 ---------- */
.page-about .about-gates {
  display: grid;
  gap: 16px;
}

.page-about .about-gate {
  position: relative;
  display: grid;
  gap: 10px;
  padding: 24px 22px 26px;
  background: var(--sand);
  box-shadow: -6px 6px 0 rgba(14, 42, 71, 0.07);
  transition: transform 0.24s ease, box-shadow 0.24s ease;
}

.page-about .about-gate::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 3px;
  background: var(--coral);
  transform: scaleY(0.32);
  transform-origin: top;
  transition: transform 0.28s ease;
}

.page-about .about-gate:hover,
.page-about .about-gate:focus-within {
  transform: translateY(-4px);
  box-shadow: -8px 12px 0 rgba(14, 42, 71, 0.1);
}

.page-about .about-gate:hover::before,
.page-about .about-gate:focus-within::before {
  transform: scaleY(1);
}

.page-about .about-gate--blue {
  background: var(--blue-deep);
  color: var(--paper);
}

.page-about .about-gate--blue .about-gate__title {
  color: var(--paper);
}

.page-about .about-gate--blue .about-gate__text,
.page-about .about-gate--blue .about-gate__list li {
  color: var(--paper);
  opacity: 0.86;
}

.page-about .about-gate--paper {
  background: var(--mist-blue);
}

.page-about .about-gate__num {
  margin: 0;
  font-size: 30px;
  font-weight: 200;
  color: var(--coral);
}

.page-about .about-gate--paper .about-gate__num {
  color: var(--blue-deep);
  opacity: 0.55;
}

.page-about .about-gate__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 19px;
  line-height: 1.4;
  letter-spacing: 0.02em;
  color: var(--blue-deep);
}

.page-about .about-gate__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
}

.page-about .about-gate__list {
  display: grid;
  gap: 7px;
  margin: 4px 0 6px;
  padding: 0;
  list-style: none;
}

.page-about .about-gate__list li {
  position: relative;
  padding-left: 16px;
  font-size: 13.5px;
  line-height: 1.65;
}

.page-about .about-gate__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 6px;
  height: 1px;
  background: var(--coral);
}

.page-about .about-gate__link {
  justify-self: start;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding-right: 4px;
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.04em;
  color: var(--blue-deep);
  text-decoration: none;
  border-bottom: 1px solid var(--coral);
}

.page-about .about-gate--blue .about-gate__link {
  color: var(--coral-soft);
  border-bottom-color: var(--coral-soft);
}

.page-about .about-gate__link:hover,
.page-about .about-gate__link:focus-visible {
  border-bottom-width: 2px;
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  display: grid;
  gap: 26px;
}

.page-about .about-team__bars {
  display: grid;
  gap: 10px;
  align-content: start;
}

.page-about .team-bar {
  display: grid;
  grid-template-columns: auto 1fr;
  align-items: center;
  gap: 4px 12px;
  position: relative;
  padding: 14px 16px;
  color: var(--paper);
  background: var(--blue-deep);
  transition: background 0.22s ease;
}

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

.page-about .team-bar--adapt {
  width: 100%;
  background: var(--blue-deep);
}

.page-about .team-bar--service {
  width: 91%;
  background: var(--blue-sub);
}

.page-about .team-bar--content {
  width: 68%;
  background: #1d4a72;
}

.page-about .team-bar--product {
  width: 56%;
  background: var(--blue-deep);
}

.page-about .team-bar__num {
  font-size: 22px;
  font-weight: 300;
  line-height: 1;
  color: var(--coral-soft);
}

.page-about .team-bar__label {
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.03em;
  line-height: 1.4;
}

.page-about .team-bar__note {
  grid-column: 1 / -1;
  margin: 0;
  max-height: 0;
  overflow: hidden;
  font-size: 13px;
  line-height: 1.65;
  opacity: 0;
  transition: max-height 0.28s ease, opacity 0.24s ease, margin 0.24s ease;
}

.page-about .team-bar:hover .team-bar__note,
.page-about .team-bar:focus .team-bar__note,
.page-about .team-bar:focus-within .team-bar__note {
  max-height: 6em;
  margin-top: 6px;
  opacity: 0.86;
}

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

/* ---------- 中段留白 ---------- */
.page-about .about-interlude {
  display: flex;
  align-items: center;
  min-height: 46vh;
  padding-block: clamp(48px, 10vw, 120px);
  border-top: 1px solid var(--line-ink);
  border-bottom: 1px solid var(--line-ink);
}

.page-about .about-interlude p {
  margin: 0;
  max-width: 20em;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(24px, 5vw, 46px);
  line-height: 1.32;
  letter-spacing: 0.02em;
  color: var(--blue-deep);
}

/* ---------- 版本时间轴 ---------- */
.page-about .about-timeline {
  position: relative;
  display: grid;
  margin-top: 8px;
  border-left: 1px solid var(--line-ink);
  margin-left: 6px;
}

.page-about .tl-item {
  position: relative;
  border-bottom: 1px solid var(--line-ink);
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 30px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--mist);
}

.page-about .tl-item[open]::before {
  background: var(--coral);
  box-shadow: 0 0 0 4px rgba(255, 107, 61, 0.18);
}

.page-about .tl-item__summary {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 12px;
  min-height: 64px;
  padding: 16px 6px 16px 18px;
  cursor: pointer;
  list-style: none;
}

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

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

.page-about .tl-item__num {
  font-size: 20px;
  font-weight: 300;
  color: var(--blue-deep);
  opacity: 0.55;
}

.page-about .tl-item[open] .tl-item__num {
  color: var(--coral);
  opacity: 1;
}

.page-about .tl-item__title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 16px;
  line-height: 1.4;
  letter-spacing: 0.02em;
  color: var(--blue-deep);
}

.page-about .tl-item__tag {
  padding: 3px 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  white-space: nowrap;
  color: var(--blue-deep);
  border: 1px solid var(--line-ink);
  background: var(--sand);
}

.page-about .tl-item__tag--coral {
  color: var(--paper);
  background: var(--coral);
  border-color: var(--coral);
}

.page-about .tl-item__body {
  display: grid;
  gap: 10px;
  padding: 0 6px 24px 18px;
}

.page-about .tl-item__body p {
  margin: 0;
  max-width: 34em;
  font-size: 15px;
  line-height: 1.75;
}

.page-about .tl-item__fix {
  padding-left: 14px;
  border-left: 2px solid var(--coral-soft);
  opacity: 0.82;
}

.page-about .about-timeline__fig {
  margin: 30px 0 0;
}

/* ---------- 片区 ---------- */
.page-about .about-regions {
  display: grid;
  gap: 26px;
}

.page-about .about-regions__text p {
  margin: 0 0 14px;
  max-width: 32em;
  font-size: 16px;
  line-height: 1.78;
}

.page-about .about-map {
  display: grid;
  gap: 0;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line-ink);
}

.page-about .about-map li {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 2px;
  font-size: 14px;
  line-height: 1.6;
  border-bottom: 1px solid var(--line-ink);
}

.page-about .about-map__dot {
  flex: none;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--coral);
}

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

/* ---------- 自查流程 ---------- */
.page-about .about-check {
  display: grid;
  gap: 12px;
  margin-top: 28px;
}

.page-about .about-check__item {
  display: grid;
  grid-template-columns: auto 1fr;
  align-items: center;
  gap: 16px;
  padding: 16px 18px;
  background: var(--sand);
}

.page-about .about-check__num {
  font-size: 34px;
  font-weight: 200;
  line-height: 1;
  color: var(--coral);
}

.page-about .about-check__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.65;
  color: var(--blue-deep);
}

/* ---------- 结尾 ---------- */
.page-about .about-cta {
  padding-block: clamp(40px, 7vw, 72px);
}

.page-about .about-cta .about-cta__inner {
  display: grid;
  gap: 16px;
}

.page-about .about-cta__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(24px, 4.4vw, 38px);
  line-height: 1.2;
  letter-spacing: 0.02em;
  color: var(--paper);
}

.page-about .about-cta__text {
  margin: 0;
  max-width: 40em;
  font-size: 15px;
  line-height: 1.78;
  color: var(--paper);
  opacity: 0.84;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 6px;
}

.page-about .about-cta__meta {
  margin: 10px 0 0;
  font-family: var(--font-mono);
  font-size: 11.5px;
  line-height: 1.8;
  letter-spacing: 0.04em;
  color: var(--mist-blue);
}

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

/* ---------- 平板 ---------- */
@media (min-width: 720px) {
  .page-about .about-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-stat {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }

  .page-about .about-gates {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
  }

  .page-about .about-gate:nth-child(1) {
    margin-top: 0;
  }

  .page-about .about-gate:nth-child(2) {
    margin-top: 28px;
  }

  .page-about .about-gate:nth-child(3) {
    margin-top: 56px;
  }

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

  .page-about .about-check__item {
    grid-template-columns: 1fr;
    align-items: start;
    gap: 8px;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 1000px) {
  .page-about .about-hero {
    padding-block: 32px 56px;
  }

  .page-about .about-hero__lower {
    grid-template-columns: minmax(0, 1.55fr) minmax(240px, 0.85fr);
    align-items: end;
    gap: clamp(28px, 5vw, 72px);
  }

  .page-about .about-hero__facts {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    padding-top: 0;
    border-top: none;
  }

  .page-about .about-body {
    display: grid;
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    column-gap: clamp(20px, 3vw, 44px);
  }

  .page-about .about-rail {
    display: block;
    position: relative;
  }

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

  .page-about .about-rail__inner {
    position: sticky;
    top: calc(var(--header-h) + 40px);
    display: flex;
    flex-direction: column;
    gap: clamp(44px, 8vh, 84px);
    padding-left: 24px;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.16em;
    color: var(--blue-deep);
    opacity: 0.45;
  }

  .page-about .about-rail__inner span {
    position: relative;
  }

  .page-about .about-rail__inner span::before {
    content: "";
    position: absolute;
    left: -21px;
    top: 50%;
    width: 7px;
    height: 7px;
    margin-top: -3.5px;
    border-radius: 50%;
    background: var(--mist);
  }

  .page-about .about-sec {
    padding-block: clamp(56px, 6.4vw, 96px);
  }

  .page-about .about-gates {
    gap: 18px;
  }

  .page-about .about-team {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.92fr);
    align-items: start;
    gap: clamp(28px, 4vw, 56px);
  }

  .page-about .about-regions {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: start;
    gap: clamp(28px, 4vw, 56px);
  }

  .page-about .about-sec--right {
    max-width: 900px;
  }

  .page-about .about-timeline {
    margin-left: 10px;
    max-width: 860px;
  }

  .page-about .tl-item__summary {
    grid-template-columns: 64px 1fr auto;
    padding: 18px 14px 18px 26px;
    min-height: 72px;
  }

  .page-about .tl-item__num {
    font-size: 26px;
  }

  .page-about .tl-item__title {
    font-size: 18px;
  }

  .page-about .tl-item__body {
    padding: 0 14px 28px 90px;
  }

  .page-about .about-timeline__fig {
    max-width: 860px;
  }

  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    align-items: start;
    column-gap: clamp(24px, 4vw, 56px);
  }

  .page-about .about-cta__title {
    grid-column: 1;
  }

  .page-about .about-cta__text {
    grid-column: 2;
    grid-row: 1 / span 2;
    padding-top: 4px;
  }

  .page-about .about-cta__actions {
    grid-column: 1;
  }

  .page-about .about-cta__meta {
    grid-column: 1 / -1;
  }

  .page-about .team-bar__note {
    max-height: 0;
  }
}

@media (min-width: 1240px) {
  .page-about .about-sec--tight {
    max-width: 760px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-gate,
  .page-about .about-gate::before,
  .page-about .team-bar,
  .page-about .team-bar__note {
    transition: none;
  }
}