.page-about {
  --about-axis: 36px;
  --about-node: 12px;
  --about-card-bg: #FFFFFF;
  background: var(--paper);
  color: var(--ink);
  padding-bottom: 88px;
}

.page-about .wrap {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: 20px;
}

.page-about .section {
  padding-block: 46px;
}

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

.page-about .eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--orange);
  margin: 0;
  text-transform: uppercase;
}

.page-about .section-title {
  font-family: var(--font-serif);
  font-size: clamp(24px, 5.4vw, 38px);
  line-height: 1.2;
  letter-spacing: -.01em;
  margin: 12px 0 0;
  max-width: 20em;
}

.page-about .section-lead {
  margin: 16px 0 0;
  max-width: 46em;
  font-size: 16px;
  line-height: 1.8;
  color: var(--graphite);
}

/* 面包屑 */
.page-about .breadcrumb {
  padding-top: 22px;
  font-size: 13px;
}

.page-about .breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  list-style: none;
  margin: 0;
  padding: 0;
  color: var(--graphite);
}

.page-about .breadcrumb-list li + li::before {
  content: "/";
  margin-right: 6px;
  color: var(--line);
}

.page-about .breadcrumb-list a {
  color: var(--graphite);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .18s var(--ease), border-color .18s var(--ease);
}

.page-about .breadcrumb-list a:hover,
.page-about .breadcrumb-list a:focus-visible {
  color: var(--blue);
  border-bottom-color: var(--blue);
}

.page-about .breadcrumb-list [aria-current="page"] {
  color: var(--ink);
}

/* 首屏 */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  padding-block: 34px 52px;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  z-index: -1;
  top: -34px;
  right: -20px;
  width: 78%;
  height: 300px;
  background:
    linear-gradient(135deg, var(--blue-mist) 0%, rgba(230, 240, 255, 0) 72%),
    repeating-linear-gradient(0deg, transparent 0 39px, rgba(10, 108, 255, .07) 39px 40px);
  clip-path: polygon(26% 0, 100% 0, 100% 100%, 0 100%);
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  z-index: -1;
  top: 208px;
  right: 8%;
  width: 64px;
  height: 64px;
  background: var(--orange);
  opacity: .18;
  transform: rotate(45deg);
  pointer-events: none;
}

.page-about .about-hero h1 {
  font-family: var(--font-serif);
  font-size: clamp(30px, 7.4vw, 54px);
  line-height: 1.14;
  letter-spacing: -.015em;
  margin: 14px 0 0;
  max-width: 18em;
}

.page-about .about-hero-lead {
  margin: 20px 0 0;
  max-width: 42em;
  font-size: 17px;
  line-height: 1.8;
  color: var(--graphite);
}

.page-about .about-hero-facts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin-top: 34px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .fact {
  background: var(--paper);
  padding: 14px 14px 16px;
}

.page-about .fact-num {
  display: block;
  font-size: 20px;
  font-weight: 700;
  color: var(--blue);
  letter-spacing: -.02em;
  line-height: 1.2;
}

.page-about .fact-label {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  line-height: 1.55;
  color: var(--graphite);
}

/* 做了什么，为谁做 */
.page-about .who-split {
  display: grid;
  gap: 16px;
  margin-top: 30px;
}

.page-about .who-card {
  position: relative;
  background: var(--about-card-bg);
  border: 1px solid var(--line);
  border-left: 3px solid var(--blue);
  padding: 20px 20px 22px;
}

.page-about .who-card--after {
  border-left-color: var(--orange);
}

.page-about .who-tag {
  margin: 0;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--blue);
}

.page-about .who-card--after .who-tag {
  color: var(--orange);
}

.page-about .who-title {
  font-family: var(--font-serif);
  font-size: 20px;
  line-height: 1.35;
  margin: 8px 0 0;
}

.page-about .who-text {
  margin: 10px 0 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--graphite);
}

/* 演进时间轴 */
.page-about .line-figure {
  margin: 0 0 32px;
}

.page-about .tl {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  position: relative;
}

.page-about .tl::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 14px;
  bottom: 14px;
  width: 2px;
  background: linear-gradient(180deg, var(--blue) 0%, var(--blue-mist) 88%, rgba(230, 240, 255, 0) 100%);
}

.page-about .tl-item {
  position: relative;
  padding-left: var(--about-axis);
  margin-bottom: 12px;
}

.page-about .tl-node {
  position: relative;
  background: var(--about-card-bg);
  border: 1px solid var(--line);
  transition: border-color .2s var(--ease), box-shadow .2s var(--ease);
}

.page-about .tl-node::before {
  content: "";
  position: absolute;
  left: calc(var(--about-axis) * -1);
  top: 18px;
  width: var(--about-node);
  height: var(--about-node);
  background: var(--about-card-bg);
  border: 2px solid var(--blue);
  transform: rotate(45deg);
  transition: background-color .2s var(--ease), border-color .2s var(--ease);
  box-sizing: border-box;
}

.page-about .tl-node[open] {
  border-color: var(--blue);
  box-shadow: 0 10px 26px rgba(10, 108, 255, .10);
}

.page-about .tl-node[open]::before {
  background: var(--orange);
  border-color: var(--orange);
}

.page-about .tl-summary {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 16px 40px 16px 16px;
  cursor: pointer;
  list-style: none;
  position: relative;
}

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

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

.page-about .tl-idx {
  flex: none;
  font-size: 12px;
  font-weight: 700;
  color: var(--orange);
  letter-spacing: .08em;
}

.page-about .tl-name {
  font-family: var(--font-serif);
  font-size: 17px;
  line-height: 1.45;
  color: var(--ink);
}

.page-about .tl-mark {
  position: absolute;
  right: 14px;
  top: 14px;
  width: 20px;
  height: 20px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--blue);
}

.page-about .tl-mark::before {
  content: "+";
  font-family: var(--font-mono);
  font-size: 17px;
  line-height: 1;
}

.page-about .tl-node[open] .tl-mark::before {
  content: "−";
}

.page-about .tl-detail {
  padding: 0 16px 18px;
  border-top: 1px solid var(--blue-mist);
  padding-top: 14px;
  color: var(--graphite);
  font-size: 15px;
  line-height: 1.78;
}

.page-about .tl-detail p {
  margin: 0;
}

/* 团队 */
.page-about .crew {
  display: grid;
  gap: 22px;
  margin-top: 30px;
}

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

.page-about .crew-rail {
  display: flex;
  gap: 14px;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
  padding-bottom: 8px;
  scrollbar-width: thin;
}

.page-about .crew-card {
  flex: 0 0 78%;
  scroll-snap-align: start;
  background: var(--about-card-bg);
  border: 1px solid var(--line);
  border-top: 3px solid var(--blue);
  padding: 18px 18px 20px;
}

.page-about .crew-card--edit {
  border-top-color: var(--orange);
}

.page-about .crew-card--support {
  border-top-color: var(--teal);
}

.page-about .crew-tag {
  margin: 0;
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--blue);
}

.page-about .crew-card--edit .crew-tag {
  color: var(--orange);
}

.page-about .crew-card--support .crew-tag {
  color: var(--teal);
}

.page-about .crew-title {
  font-family: var(--font-serif);
  font-size: 19px;
  line-height: 1.35;
  margin: 8px 0 0;
}

.page-about .crew-text {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--graphite);
}

/* 维护节奏 */
.page-about .cadence {
  display: grid;
  gap: 1px;
  margin-top: 30px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .cad-item {
  background: var(--about-card-bg);
  padding: 18px 18px 20px;
}

.page-about .cad-key {
  display: inline-block;
  font-size: 14px;
  font-weight: 700;
  color: var(--blue);
  letter-spacing: -.01em;
  border-bottom: 2px solid var(--orange-mist);
  padding-bottom: 3px;
}

.page-about .cad-text {
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--graphite);
}

/* 服务承诺 */
.page-about .serve {
  display: grid;
  gap: 26px;
}

.page-about .serve-list {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .serve-list li {
  display: grid;
  gap: 4px;
  padding: 15px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .serve-key {
  font-size: 15px;
  font-weight: 700;
  color: var(--blue);
  letter-spacing: -.01em;
}

.page-about .serve-val {
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--graphite);
}

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

/* 规模 */
.page-about .scale-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: 30px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .scale-cell {
  background: var(--about-card-bg);
  padding: 16px 14px 18px;
}

.page-about .scale-num {
  display: block;
  font-size: 18px;
  font-weight: 700;
  color: var(--ink);
  letter-spacing: -.02em;
  line-height: 1.25;
}

.page-about .scale-cell:nth-child(odd) .scale-num {
  color: var(--blue);
}

.page-about .scale-cell:nth-child(even) .scale-num {
  color: var(--orange);
}

.page-about .scale-label {
  display: block;
  margin-top: 6px;
  font-size: 12.5px;
  line-height: 1.55;
  color: var(--graphite);
}

/* 结尾入口 */
.page-about .about-next {
  padding-bottom: 0;
}

.page-about .next-frame {
  position: relative;
  background: linear-gradient(140deg, var(--blue-deep) 0%, var(--blue) 100%);
  color: #FFFFFF;
  padding: 30px 22px 32px;
  overflow: hidden;
}

.page-about .next-frame::before {
  content: "";
  position: absolute;
  top: -40px;
  right: -40px;
  width: 160px;
  height: 160px;
  background: rgba(255, 107, 53, .28);
  transform: rotate(45deg);
  pointer-events: none;
}

.page-about .next-title {
  position: relative;
  font-family: var(--font-serif);
  font-size: clamp(22px, 5vw, 32px);
  line-height: 1.25;
  margin: 0;
}

.page-about .next-lead {
  position: relative;
  margin: 12px 0 0;
  max-width: 40em;
  font-size: 15.5px;
  line-height: 1.75;
  color: rgba(255, 255, 255, .86);
}

.page-about .next-actions {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 22px;
}

.page-about .next-actions .btn--ghost {
  color: #FFFFFF;
  border-color: rgba(255, 255, 255, .55);
  background: transparent;
}

.page-about .next-actions .btn--ghost:hover,
.page-about .next-actions .btn--ghost:focus-visible {
  background: rgba(255, 255, 255, .14);
  border-color: #FFFFFF;
}

/* 响应式 */
@media (min-width: 640px) {
  .page-about .wrap {
    padding-inline: 32px;
  }

  .page-about .section {
    padding-block: 64px;
  }

  .page-about .about-hero {
    padding-block: 44px 64px;
  }

  .page-about .about-hero::before {
    right: -32px;
    width: 66%;
    height: 340px;
  }

  .page-about .about-hero::after {
    top: 236px;
    width: 78px;
    height: 78px;
  }

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

  .page-about .fact-num {
    font-size: 24px;
  }

  .page-about .who-split {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
  }

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

  .page-about .cad-item {
    padding: 22px 24px 24px;
  }

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

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

  .page-about .scale-num {
    font-size: 21px;
  }

  .page-about .next-frame {
    padding: 42px 40px 46px;
  }
}

@media (min-width: 900px) {
  .page-about .section {
    padding-block: 84px;
  }

  .page-about .about-hero {
    padding-block: 56px 84px;
  }

  .page-about .about-hero::before {
    width: 58%;
    height: 400px;
  }

  .page-about .about-hero h1 {
    max-width: 15em;
  }

  .page-about .about-hero-facts {
    margin-top: 44px;
    max-width: 760px;
  }

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

  .page-about .tl-item {
    margin-bottom: 14px;
  }

  .page-about .tl-summary {
    padding: 18px 48px 18px 22px;
  }

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

  .page-about .tl-detail {
    padding: 16px 22px 22px;
  }

  .page-about .crew {
    grid-template-columns: minmax(240px, 320px) minmax(0, 1fr);
    gap: 30px;
    align-items: start;
  }

  .page-about .crew-rail {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .crew-card {
    flex: none;
  }

  .page-about .crew-text {
    font-size: 14px;
  }

  .page-about .serve {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .serve-list {
    margin-top: 30px;
  }

  .page-about .serve-list li {
    grid-template-columns: 160px minmax(0, 1fr);
    gap: 18px;
    align-items: baseline;
    padding: 16px 0;
  }

  .page-about .about-next {
    padding-bottom: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tl-node,
  .page-about .tl-node::before,
  .page-about .breadcrumb-list a {
    transition: none;
  }
}
</PAGE_CSS>