.page-about {
  --ab-rail: 176px;
  --ab-gap: 44px;
  background: var(--ink);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: 128px 0 46px;
  border-bottom: 1px solid var(--line);
  background-image:
    repeating-linear-gradient(90deg, rgba(46, 107, 255, 0.16) 0 1px, transparent 1px 64px),
    repeating-linear-gradient(0deg, rgba(123, 242, 192, 0.07) 0 1px, transparent 1px 64px),
    linear-gradient(180deg, #123028 0%, #0b1412 70%, var(--ink) 100%);
}

.page-about .about-hero::after {
  content: "SVC / 01";
  position: absolute;
  top: calc(var(--hdr-total) + 12px);
  right: 16px;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.2em;
  color: var(--mist);
  opacity: 0.72;
}

.page-about .about-eyebrow {
  margin: 0 0 16px;
  font-size: 0.6875rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--orange-2);
}

.page-about .about-title {
  margin: 0;
  font-size: clamp(2.05rem, 7.2vw, 4.1rem);
  font-weight: 900;
  line-height: 1.02;
  letter-spacing: -0.02em;
  color: var(--paper);
  max-width: 16ch;
}

.page-about .about-lede {
  margin: 22px 0 0;
  max-width: 34em;
  font-size: 1.0625rem;
  line-height: 1.8;
  color: rgba(242, 247, 244, 0.82);
}

.page-about .about-stats {
  list-style: none;
  margin: 36px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: rgba(123, 242, 192, 0.14);
  border: 1px solid rgba(123, 242, 192, 0.14);
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 16px 16px 18px;
  background: rgba(10, 20, 18, 0.72);
}

.page-about .about-stat-num {
  font-size: 1.85rem;
  font-weight: 700;
  line-height: 1;
  color: var(--green-lt);
}

.page-about .about-stat-label {
  font-size: 0.8125rem;
  letter-spacing: 0.03em;
  color: var(--mist);
}

/* ---------- 主体栅格 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  align-items: start;
  padding-top: 0;
  padding-bottom: 84px;
}

/* ---------- 左侧索引轴 ---------- */
.page-about .about-rail {
  position: sticky;
  top: var(--hdr-total);
  z-index: 6;
  padding: 10px 0;
  background: rgba(11, 15, 14, 0.94);
  border-bottom: 1px solid var(--line);
  margin-bottom: 8px;
}

.page-about .about-rail-head {
  display: none;
  margin: 0 0 14px 16px;
  font-size: 0.625rem;
  letter-spacing: 0.22em;
  color: var(--mist);
}

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

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

.page-about .about-rail-link {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 14px;
  min-height: 44px;
  color: var(--mist);
  text-decoration: none;
  white-space: nowrap;
  border: 1px solid rgba(123, 242, 192, 0.18);
  transition: color 0.2s ease, border-color 0.2s ease, background-color 0.2s ease;
}

.page-about .about-rail-num {
  font-size: 0.6875rem;
  letter-spacing: 0.1em;
  color: var(--green);
}

.page-about .about-rail-text {
  font-size: 0.875rem;
}

.page-about .about-rail-link:hover,
.page-about .about-rail-link:focus-visible {
  color: var(--green-lt);
  border-color: rgba(255, 90, 31, 0.55);
  background: rgba(31, 191, 117, 0.1);
  outline: none;
}

/* ---------- 章节通用 ---------- */
.page-about .about-flow {
  min-width: 0;
}

.page-about .about-sec {
  padding: 40px 0 8px;
  border-top: 1px solid rgba(123, 242, 192, 0.11);
}

.page-about .about-sec:first-child {
  padding-top: 28px;
  border-top: 0;
}

.page-about .about-sec .section-title {
  margin: 8px 0 0;
  font-size: clamp(1.5rem, 4.4vw, 2.25rem);
  font-weight: 900;
  line-height: 1.18;
  letter-spacing: -0.01em;
  color: var(--paper);
  max-width: 22ch;
}

.page-about .about-copy {
  margin-top: 20px;
}

.page-about .about-copy p {
  margin: 0 0 14px;
  max-width: 40em;
  font-size: 1rem;
  line-height: 1.85;
  color: rgba(242, 247, 244, 0.8);
}

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

/* ---------- 概况分栏 ---------- */
.page-about .about-split {
  display: grid;
  gap: 22px;
  margin-top: 22px;
}

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

.page-about .about-fig .img-frame {
  border: 1px solid var(--line);
  overflow: hidden;
}

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

.page-about .about-fig .img-cap {
  margin: 10px 0 0;
  font-size: 0.8125rem;
  line-height: 1.65;
  color: var(--mist);
}

.page-about .about-fig--wide {
  margin-top: 30px;
}

/* ---------- 地市覆盖 ---------- */
.page-about .about-cities {
  margin-top: 34px;
}

.page-about .about-cities-head {
  margin: 0 0 12px;
  font-size: 0.6875rem;
  letter-spacing: 0.2em;
  color: var(--orange-2);
}

.page-about .about-city-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(78px, 1fr));
  gap: 6px;
}

.page-about .about-city {
  position: relative;
  padding: 16px 8px 11px;
  text-align: center;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--green-lt);
  background: rgba(31, 191, 117, 0.08);
  border: 1px solid rgba(31, 191, 117, 0.24);
}

.page-about .about-city::before {
  content: "";
  position: absolute;
  top: 6px;
  left: 50%;
  width: 5px;
  height: 5px;
  margin-left: -2.5px;
  background: var(--green);
  border-radius: 50%;
}

/* ---------- 团队 ---------- */
.page-about .about-team-bg {
  position: relative;
  margin: 26px 0 30px;
  border: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-team-bg img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.9) contrast(1.06);
}

.page-about .about-team-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(11, 15, 14, 0.08) 0%, rgba(11, 15, 14, 0.76) 100%);
  pointer-events: none;
}

.page-about .about-team {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 26px;
}

.page-about .about-team-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 10px;
}

.page-about .about-team-name {
  margin: 0;
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-team-num {
  font-size: 1.4rem;
  font-weight: 700;
  line-height: 1;
  color: var(--green-lt);
}

.page-about .about-team-num small {
  margin-left: 2px;
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--mist);
}

.page-about .about-team-bar {
  height: 10px;
  background: rgba(242, 247, 244, 0.07);
  overflow: hidden;
}

.page-about .about-team-fill {
  display: block;
  height: 100%;
  width: var(--w, 40%);
  transition: filter 0.25s ease, width 0.6s ease;
}

.page-about .about-team-item--a {
  --w: 55.3%;
}

.page-about .about-team-item--b {
  --w: 31.6%;
}

.page-about .about-team-item--c {
  --w: 13.1%;
}

.page-about .about-team-item--a .about-team-fill {
  background: linear-gradient(90deg, #123028, var(--green));
}

.page-about .about-team-item--b .about-team-fill {
  background: linear-gradient(90deg, #12233f, var(--blue));
}

.page-about .about-team-item--c .about-team-fill {
  background: linear-gradient(90deg, #46200e, var(--orange-2));
}

.page-about .about-team-item:hover .about-team-fill,
.page-about .about-team-item:focus-within .about-team-fill {
  filter: brightness(1.2);
}

.page-about .about-team-note {
  margin: 12px 0 0;
  max-width: 42em;
  font-size: 0.9375rem;
  line-height: 1.75;
  color: rgba(242, 247, 244, 0.7);
}

/* ---------- 版本时间轴 ---------- */
.page-about .about-tl-scroll {
  position: relative;
  margin-top: 30px;
  overflow-x: auto;
  overflow-y: hidden;
  padding-bottom: 16px;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .about-tl-scroll::-webkit-scrollbar {
  height: 4px;
}

.page-about .about-tl-scroll::-webkit-scrollbar-thumb {
  background: rgba(31, 191, 117, 0.45);
}

.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  min-width: max-content;
}

.page-about .about-tl-item {
  position: relative;
  flex: 0 0 232px;
  padding: 58px 20px 0 0;
}

.page-about .about-tl-item::before {
  content: "";
  position: absolute;
  top: 27px;
  left: 32px;
  right: 4px;
  height: 1px;
  background: linear-gradient(90deg, rgba(31, 191, 117, 0.6), rgba(46, 107, 255, 0.3));
  transform: rotate(-10deg);
  transform-origin: left center;
}

.page-about .about-tl-item:last-child::before {
  background: linear-gradient(90deg, rgba(255, 90, 31, 0.6), transparent 88%);
}

.page-about .about-tl-node {
  position: absolute;
  top: 6px;
  left: 0;
  z-index: 2;
  width: 40px;
  height: 40px;
  display: grid;
  place-items: center;
  font-size: 0.6875rem;
  font-weight: 700;
  color: var(--ink);
  background: var(--green);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 12px), calc(100% - 12px) 100%, 0 100%);
}

.page-about .about-tl-item:last-child .about-tl-node {
  background: var(--grad-cta);
  color: #ffffff;
}

.page-about .about-tl-card {
  position: relative;
  height: 100%;
  padding: 16px 15px 18px;
  background: rgba(18, 48, 40, 0.55);
  border: 1px solid var(--line);
  transition: transform 0.22s ease, border-color 0.22s ease, background-color 0.22s ease;
}

.page-about .about-tl-card::before {
  content: "";
  position: absolute;
  top: -1px;
  left: -1px;
  width: 42px;
  height: 3px;
  background: var(--grad-cta);
}

.page-about .about-tl-card:hover,
.page-about .about-tl-card:focus-within {
  transform: translateY(-4px);
  border-color: rgba(255, 90, 31, 0.5);
  background: rgba(18, 48, 40, 0.85);
}

.page-about .about-tl-card h3 {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-tl-card p {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.75;
  color: rgba(242, 247, 244, 0.72);
}

/* ---------- 服务节奏 ---------- */
.page-about .about-rhythm {
  margin-top: 26px;
  display: grid;
  gap: 1px;
  background: rgba(123, 242, 192, 0.14);
  border: 1px solid rgba(123, 242, 192, 0.14);
}

.page-about .about-rhythm-item {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 22px 20px 24px;
  background: rgba(10, 20, 18, 0.78);
}

.page-about .about-rhythm-num {
  font-size: 1.4rem;
  font-weight: 700;
  line-height: 1;
  color: var(--orange-2);
}

.page-about .about-rhythm-item h3 {
  margin: 0;
  font-size: 0.9375rem;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-rhythm-item p {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.78;
  color: rgba(242, 247, 244, 0.68);
}

/* ---------- 协作网络 ---------- */
.page-about .about-net-list {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: rgba(123, 242, 192, 0.14);
  border: 1px solid rgba(123, 242, 192, 0.14);
}

.page-about .about-net-item {
  padding: 22px 20px 24px;
  background: rgba(18, 48, 40, 0.5);
}

.page-about .about-net-num {
  display: block;
  margin-bottom: 12px;
  font-size: 1.75rem;
  font-weight: 700;
  line-height: 1;
  color: var(--green-lt);
}

.page-about .about-net-item h3 {
  margin: 0 0 8px;
  font-size: 0.9375rem;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-net-item p {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.78;
  color: rgba(242, 247, 244, 0.68);
}

/* ---------- 收尾 ---------- */
.page-about .about-tail {
  margin-top: 56px;
  padding: 30px 24px 32px;
  display: flex;
  flex-direction: column;
  gap: 22px;
  background: var(--grad-deep);
  border: 1px solid var(--line-strong);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%);
}

.page-about .about-tail-title {
  margin: 0 0 10px;
  font-size: clamp(1.25rem, 3.6vw, 1.75rem);
  font-weight: 900;
  line-height: 1.2;
  color: var(--paper);
}

.page-about .about-tail-text {
  margin: 0;
  max-width: 40em;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: rgba(242, 247, 244, 0.76);
}

.page-about .about-tail-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-tail-actions .btn {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 20px;
  text-decoration: none;
}

/* ---------- 窄屏到中屏 ---------- */
@media (max-width: 999px) {
  .page-about .about-hero {
    padding: 116px 0 38px;
  }

  .page-about .about-layout {
    padding-bottom: 64px;
  }

  .page-about .about-sec {
    padding-top: 34px;
  }
}

@media (min-width: 700px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-stat {
    padding: 20px 18px 22px;
  }

  .page-about .about-city-grid {
    grid-template-columns: repeat(auto-fill, minmax(92px, 1fr));
  }

  .page-about .about-rhythm {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .page-about .about-split {
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr);
    gap: 30px;
    align-items: start;
  }
}

@media (min-width: 1000px) {
  .page-about .about-hero {
    padding: 152px 0 62px;
  }

  .page-about .about-hero::after {
    right: 40px;
  }

  .page-about .about-layout {
    grid-template-columns: var(--ab-rail) minmax(0, 1fr);
    column-gap: var(--ab-gap);
  }

  .page-about .about-rail {
    top: calc(var(--hdr-total) + 26px);
    padding: 22px 0 0 0;
    background: transparent;
    border-bottom: 0;
    border-left: 1px solid var(--line);
    margin-bottom: 0;
  }

  .page-about .about-rail-head {
    display: block;
  }

  .page-about .about-rail-list {
    flex-direction: column;
    gap: 2px;
    padding: 0;
    overflow: visible;
  }

  .page-about .about-rail-link {
    min-height: 0;
    padding: 7px 0 7px 16px;
    margin-left: -1px;
    border: 0;
    border-left: 2px solid transparent;
  }

  .page-about .about-rail-link:hover,
  .page-about .about-rail-link:focus-visible {
    border-color: transparent;
    border-left-color: var(--orange);
    background: linear-gradient(90deg, rgba(255, 90, 31, 0.14), transparent 82%);
  }

  .page-about .about-sec {
    padding: 58px 0 10px;
  }

  .page-about .about-sec:first-child {
    padding-top: 40px;
  }

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

  .page-about .about-tail {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 32px;
    padding: 34px 32px 36px;
  }

  .page-about .about-tail-actions {
    flex: 0 0 auto;
    justify-content: flex-end;
  }
}

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

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

  .page-about .about-tl-scroll {
    scroll-behavior: auto;
  }
}