.page-about {
  --about-rule: 1px solid var(--steel);
  --about-axis: 104px;
  --about-soft: rgba(169, 188, 205, .7);
  background: var(--ink);
  color: var(--paper);
  overflow-x: hidden;
}

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

.page-about .breadcrumb {
  padding-block: 18px 0;
}

.page-about .about-lede,
.page-about .about-lead {
  font-size: 16px;
  line-height: 1.85;
  color: var(--mist);
  max-width: 36em;
}

.page-about h2 {
  font-size: clamp(26px, 5.2vw, 40px);
  line-height: 1.22;
  letter-spacing: -0.02em;
  margin: 10px 0 14px;
}

.page-about h3 {
  font-size: 18px;
  line-height: 1.5;
  letter-spacing: -0.01em;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: 10px 0 56px;
  border-bottom: var(--about-rule);
  background:
    radial-gradient(120% 90% at 88% 0%, rgba(31, 224, 208, .13), transparent 58%),
    linear-gradient(180deg, var(--ink) 0%, #071a2d 100%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 40px;
  background-image: repeating-linear-gradient(90deg, var(--steel) 0 1px, transparent 1px 40px);
  opacity: .5;
  pointer-events: none;
}

.page-about .about-hero-inner {
  display: grid;
  gap: 28px;
  align-items: end;
}

.page-about .about-hero-copy h1 {
  font-size: clamp(32px, 7.6vw, 64px);
  line-height: 1.12;
  letter-spacing: -0.025em;
  margin: 12px 0 18px;
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .about-hero-visual {
  position: relative;
  margin: 0;
  border: var(--about-rule);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
  background: var(--deep);
  min-height: 180px;
}

.page-about .about-hero-visual img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: .82;
}

.page-about .about-hero-visual .media-cap {
  position: absolute;
  right: 0;
  bottom: 0;
  padding: 6px 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .04em;
  color: var(--cyan-soft);
  background: rgba(6, 21, 39, .82);
  border-top: 1px solid var(--steel);
  border-left: 1px solid var(--steel);
}

.page-about .about-hero-panel {
  margin-top: 26px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  border: var(--about-rule);
  gap: 1px;
  background: var(--steel);
  overflow: hidden;
}

.page-about .about-hero-stat {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 16px 14px;
  background: rgba(11, 41, 66, .78);
  backdrop-filter: blur(8px);
}

.page-about .about-hero-num {
  font-size: 26px;
  line-height: 1.1;
  color: var(--amber);
}

.page-about .about-hero-pct {
  font-size: 15px;
  margin-left: 1px;
}

.page-about .about-hero-key {
  font-size: 12.5px;
  color: var(--mist);
  letter-spacing: .02em;
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  padding: 54px 0 46px;
  border-bottom: var(--about-rule);
}

.page-about .about-tl-grid {
  display: grid;
  gap: 26px;
}

.page-about .about-rail {
  order: 2;
  border-top: var(--about-rule);
  padding-top: 16px;
}

.page-about .about-rail-title {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--mist);
  margin-bottom: 12px;
}

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

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

.page-about .about-rail-nav a {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 8px 12px;
  min-width: 84px;
  border: 1px solid var(--steel);
  color: var(--mist);
  text-decoration: none;
  transition: color .25s var(--ease), border-color .25s var(--ease), background-color .25s var(--ease);
}

.page-about .about-rail-nav .about-year {
  font-size: 15px;
  color: inherit;
}

.page-about .about-rail-label {
  font-size: 11.5px;
  letter-spacing: .04em;
}

.page-about .about-rail-nav a:hover {
  color: var(--cyan-soft);
  border-color: var(--cyan);
}

.page-about .about-rail-nav a[aria-current="location"] {
  color: var(--ink);
  background: var(--cyan);
  border-color: var(--cyan);
}

.page-about .about-tl-body { order: 1; }

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

.page-about .about-step {
  position: relative;
  padding: 0 0 30px 26px;
  border-left: 1px solid var(--steel);
}

.page-about .about-step:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.page-about .about-step::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 8px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(31, 224, 208, .14);
  animation: about-breathe 3s ease-in-out infinite;
}

@keyframes about-breathe {
  0%, 100% { box-shadow: 0 0 0 4px rgba(31, 224, 208, .12); }
  50% { box-shadow: 0 0 0 7px rgba(31, 224, 208, .05); }
}

.page-about .about-step-head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
}

.page-about .about-step-year {
  display: inline-block;
  padding: 3px 9px;
  font-size: 13px;
  color: var(--black);
  background: var(--amber);
  letter-spacing: .06em;
}

.page-about .about-step p {
  margin: 10px 0 0;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--mist);
  max-width: 34em;
}

/* ---------- 四条业务线 ---------- */
.page-about .about-lines {
  padding: 52px 0 56px;
  background: linear-gradient(180deg, #071a2d, var(--ink));
  border-bottom: var(--about-rule);
}

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

.page-about .about-line-grid {
  display: grid;
  gap: 14px;
  grid-template-columns: 1fr;
}

.page-about .about-line {
  position: relative;
  padding: 22px 20px 18px;
  background: rgba(11, 41, 66, .62);
  border: var(--about-rule);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%);
  transition: transform .25s var(--ease), border-color .25s var(--ease), background-color .25s var(--ease);
}

.page-about .about-line:hover {
  transform: translateY(-4px);
  border-color: var(--cyan);
  background: rgba(16, 62, 92, .72);
}

.page-about .about-plate {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--ink);
  background: var(--amber);
  padding: 2px 8px;
  margin-bottom: 12px;
}

.page-about .about-line h3 {
  margin: 0 0 8px;
  color: var(--paper);
}

.page-about .about-line p {
  margin: 0 0 14px;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--mist);
}

.page-about .about-line-link {
  display: inline-block;
  font-size: 14px;
  font-weight: 700;
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .25s var(--ease), border-color .25s var(--ease);
}

.page-about .about-line-link:hover {
  color: var(--cyan-soft);
  border-bottom-color: var(--cyan-soft);
}

/* ---------- 团队（暖纸区） ---------- */
.page-about .about-team {
  position: relative;
  padding: 52px 0;
  background-color: var(--paper);
  background-image:
    radial-gradient(circle at 14% 22%, rgba(18, 16, 14, .045) 0 1px, transparent 1px),
    radial-gradient(circle at 76% 68%, rgba(18, 16, 14, .04) 0 1px, transparent 1px);
  background-size: 5px 5px, 7px 7px;
  color: var(--black);
}

.page-about .about-team .eyebrow {
  color: #7a5a12;
}

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

.page-about .about-team-figure {
  margin: 0;
  border: 1px solid rgba(18, 16, 14, .18);
  background: #e6ddca;
  position: relative;
}

.page-about .about-team-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  aspect-ratio: 3 / 2;
}

.page-about .about-team-figure .media-cap {
  position: absolute;
  left: 0;
  bottom: 0;
  padding: 5px 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--paper);
  background: rgba(18, 16, 14, .8);
}

.page-about .about-team-copy h2 { color: var(--black); margin-top: 8px; }

.page-about .about-team-copy > p {
  font-size: 15.5px;
  line-height: 1.85;
  color: #3b3934;
  max-width: 34em;
}

.page-about .about-bar {
  display: flex;
  gap: 2px;
  height: 40px;
  margin: 20px 0 16px;
  background: var(--black);
  border: 1px solid var(--black);
}

.page-about .about-bar-seg {
  display: block;
  height: 100%;
}

.page-about .about-bar-seg--dev {
  flex: 68;
  background: var(--deep);
}

.page-about .about-bar-seg--care {
  flex: 46;
  background: var(--cyan);
}

.page-about .about-bar-seg--ops {
  flex: 22;
  background: var(--amber);
}

.page-about .about-bar-legend {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .about-bar-legend li {
  display: grid;
  grid-template-columns: 12px auto 1fr;
  grid-template-areas:
    "dot name num"
    ".  note note";
  column-gap: 10px;
  row-gap: 2px;
  align-items: center;
  padding-bottom: 9px;
  border-bottom: 1px solid rgba(18, 16, 14, .12);
}

.page-about .about-dot {
  grid-area: dot;
  width: 10px;
  height: 10px;
  display: block;
}

.page-about .about-dot--dev { background: var(--deep); }
.page-about .about-dot--care { background: var(--cyan); }
.page-about .about-dot--ops { background: var(--amber); }

.page-about .about-legend-name {
  grid-area: name;
  font-weight: 700;
  font-size: 14.5px;
  color: var(--black);
}

.page-about .about-legend-num {
  grid-area: num;
  justify-self: end;
  font-size: 16px;
  color: #7a5a12;
}

.page-about .about-legend-note {
  grid-area: note;
  font-size: 13px;
  line-height: 1.6;
  color: #5d5a52;
}

.page-about .about-team-foot {
  margin-top: 18px;
  padding: 14px 16px;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--black);
  border-left: 3px solid var(--amber);
  background: rgba(242, 179, 75, .16);
  max-width: 40em;
}

/* ---------- 服务半径 ---------- */
.page-about .about-reach {
  position: relative;
  padding: 54px 0 50px;
  border-top: var(--about-rule);
  border-bottom: var(--about-rule);
  overflow: hidden;
}

.page-about .about-reach-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.page-about .about-reach-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: .28;
  filter: saturate(.8);
}

.page-about .about-reach::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(6, 21, 39, .88) 0%, rgba(6, 21, 39, .72) 45%, rgba(6, 21, 39, .95) 100%);
  z-index: 1;
}

.page-about .about-reach-inner {
  position: relative;
  z-index: 2;
}

.page-about .about-reach-grid {
  display: grid;
  gap: 12px;
  margin-top: 24px;
}

.page-about .about-reach-card {
  padding: 18px 18px 16px;
  border: 1px solid var(--steel);
  background: rgba(11, 41, 66, .55);
  backdrop-filter: blur(6px);
}

.page-about .about-reach-card h3 {
  margin: 0 0 8px;
  color: var(--cyan-soft);
  font-size: 16px;
}

.page-about .about-reach-card p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--mist);
}

.page-about .about-flow {
  margin-top: 30px;
  padding-top: 22px;
  border-top: 1px dashed var(--steel);
}

.page-about .about-flow-title {
  margin: 0 0 14px;
  font-size: 16px;
  color: var(--amber);
}

.page-about .about-flow-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-flow-list li {
  display: grid;
  grid-template-columns: 58px 1fr;
  gap: 12px;
  align-items: start;
}

.page-about .about-flow-num {
  font-size: 12.5px;
  letter-spacing: .06em;
  color: var(--cyan);
  padding-top: 2px;
  border-right: 1px solid var(--steel);
}

.page-about .about-flow-list p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .about-flow-foot {
  margin: 18px 0 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--paper);
}

.page-about .about-flow-foot .num {
  color: var(--amber);
  font-size: 17px;
}

/* ---------- 指标条 ---------- */
.page-about .about-metrics {
  padding: 52px 0 46px;
  background: var(--ink);
}

.page-about .about-metric-strip {
  display: grid;
  gap: 1px;
  margin-top: 26px;
  background: var(--steel);
  border: var(--about-rule);
}

.page-about .about-metric {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 20px 18px;
  background: #071a2d;
}

.page-about .about-metric-num {
  font-size: clamp(32px, 8vw, 46px);
  line-height: 1;
  color: var(--cyan);
  letter-spacing: .02em;
}

.page-about .about-metric-unit {
  font-size: 16px;
  margin-left: 2px;
  color: var(--cyan-soft);
}

.page-about .about-metric-key {
  font-size: 14px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-metric-note {
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--mist);
}

.page-about .about-cadence {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .about-cadence li {
  display: grid;
  grid-template-columns: 54px 1fr;
  gap: 12px;
  align-items: baseline;
  padding-bottom: 10px;
  border-bottom: 1px solid rgba(16, 62, 92, .85);
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .about-cadence-key {
  font-size: 13px;
  color: var(--amber);
  letter-spacing: .06em;
}

.page-about .about-cadence-foot {
  margin: 16px 0 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--soft, var(--mist));
}

/* ---------- 收口 ---------- */
.page-about .about-close {
  padding: 46px 0 60px;
  border-top: var(--about-rule);
  background: linear-gradient(180deg, #071a2d, var(--ink));
}

.page-about .about-close-grid {
  display: grid;
  gap: 26px;
}

.page-about .about-close-copy h2 {
  color: var(--paper);
}

.page-about .about-close-copy p {
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--mist);
  max-width: 34em;
  margin: 0 0 12px;
}

.page-about .about-close-card {
  border: var(--about-rule);
  background: rgba(11, 41, 66, .62);
  backdrop-filter: blur(6px);
  padding: 18px 18px 8px;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%);
}

.page-about .about-close-card-label {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--mist);
}

.page-about .about-close-link {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 14px 4px;
  font-size: 15.5px;
  font-weight: 700;
  color: var(--paper);
  text-decoration: none;
  border-bottom: 1px solid var(--steel);
  transition: color .25s var(--ease), border-color .25s var(--ease);
}

.page-about .about-close-link:last-child { border-bottom: none; }

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

.page-about .about-close-arrow {
  font-family: var(--font-mono);
  color: var(--cyan);
  transition: transform .25s var(--ease);
}

.page-about .about-close-link:hover .about-close-arrow {
  transform: translateX(4px);
  color: var(--amber);
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero-panel {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-line-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }

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

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

  .page-about .about-flow-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }

  .page-about .about-flow-list li {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .page-about .about-flow-num {
    border-right: none;
    border-bottom: 1px solid var(--steel);
    padding: 0 0 6px;
  }
}

@media (min-width: 960px) {
  .page-about .about-hero {
    padding-bottom: 64px;
  }

  .page-about .about-hero-inner {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 40px;
    align-items: stretch;
  }

  .page-about .about-hero-copy {
    padding-top: 26px;
  }

  .page-about .about-hero-visual {
    min-height: 340px;
    align-self: end;
  }

  .page-about .about-hero-panel {
    margin-top: 34px;
  }

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

  .page-about .about-tl-grid {
    grid-template-columns: 168px minmax(0, 1fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .about-rail {
    order: 1;
    position: sticky;
    top: calc(var(--header-h) + 26px);
    border-top: none;
    border-left: var(--about-rule);
    padding: 0 0 0 10px;
  }

  .page-about .about-rail-nav ol {
    flex-direction: column;
    gap: 6px;
    overflow: visible;
  }

  .page-about .about-rail-nav a {
    min-width: 0;
    border: none;
    border-left: 2px solid transparent;
    padding: 7px 10px;
    background: transparent;
  }

  .page-about .about-rail-nav a:hover {
    border-left-color: var(--cyan);
    background: rgba(31, 224, 208, .06);
  }

  .page-about .about-rail-nav a[aria-current="location"] {
    background: rgba(31, 224, 208, .12);
    border-left-color: var(--cyan);
    color: var(--cyan-soft);
  }

  .page-about .about-tl-body { order: 2; }

  .page-about .about-step {
    padding-left: 34px;
    padding-bottom: 36px;
  }

  .page-about .about-line-grid {
    grid-template-columns: repeat(12, minmax(0, 1fr));
  }

  .page-about .about-line:nth-child(1) { grid-column: span 7; }
  .page-about .about-line:nth-child(2) { grid-column: span 5; }
  .page-about .about-line:nth-child(3) { grid-column: span 5; }
  .page-about .about-line:nth-child(4) { grid-column: span 7; }

  .page-about .about-line {
    padding: 26px 24px 20px;
  }

  .page-about .about-team-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .about-team-figure {
    position: sticky;
    top: calc(var(--header-h) + 26px);
  }

  .page-about .about-team {
    padding: 64px 0;
  }

  .page-about .about-close-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .about-reach-inner {
    max-width: 1000px;
  }
}

@media (min-width: 1200px) {
  .page-about .about-hero-copy h1 {
    margin-top: 18px;
  }

  .page-about .about-tl-grid {
    grid-template-columns: 184px minmax(0, 1fr);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-step::before {
    animation: none;
  }

  .page-about .about-line,
  .page-about .about-close-arrow,
  .page-about .about-rail-nav a {
    transition: none;
  }

  .page-about .about-line:hover {
    transform: none;
  }
}

.page-about {
  --soft: currentColor;
}