.page-about {
  --ab-cn: var(--cyan-400);
  --ab-or: var(--orange-500);
  --ab-gd: var(--gold-400);
  --ab-mg: var(--magenta-500);
  color: var(--paper-100);
}

/* ---------- 首屏 ---------- */
.page-about .ab-masthead {
  position: relative;
  overflow: hidden;
  border-bottom: var(--line);
  background:
    radial-gradient(120% 90% at 88% 0%, rgba(0, 229, 208, .09), transparent 62%),
    radial-gradient(90% 80% at 6% 100%, rgba(255, 106, 31, .07), transparent 58%);
}

.page-about .ab-masthead::after {
  content: "";
  position: absolute;
  inset: 0 0 0 auto;
  width: min(46%, 520px);
  background: repeating-linear-gradient(135deg, rgba(224, 23, 127, .07) 0 2px, transparent 2px 15px);
  -webkit-mask-image: linear-gradient(90deg, transparent, #000);
  mask-image: linear-gradient(90deg, transparent, #000);
  pointer-events: none;
}

.page-about .ab-masthead__inner {
  position: relative;
  z-index: 1;
  padding: clamp(28px, 6vw, 68px) 0 clamp(28px, 5vw, 56px);
}

.page-about .ab-h1 {
  margin: var(--sp-2) 0 var(--sp-3);
  font-size: clamp(30px, 7.4vw, 62px);
  font-weight: 900;
  line-height: 1.06;
  letter-spacing: -0.03em;
  max-width: 15em;
}

.page-about .ab-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: var(--sp-4) 0 0;
  padding: 0;
  background: var(--ink-700);
  border: var(--line);
}

.page-about .ab-facts > div {
  background: var(--ink-900);
  padding: var(--sp-2) var(--sp-3);
}

.page-about .ab-facts dt {
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--mist-400);
}

.page-about .ab-facts dd {
  margin: 6px 0 0;
  font-size: clamp(22px, 4.6vw, 32px);
  line-height: 1;
  color: var(--paper-100);
}

.page-about .ab-facts__unit {
  font-size: 12px;
  font-family: var(--font-sans);
  letter-spacing: .08em;
  color: var(--mist-400);
  margin-left: 4px;
}

/* ---------- 通用小节头 ---------- */
.page-about .ab-sec-head {
  max-width: 760px;
  margin: 0 0 var(--sp-4);
}

.page-about .ab-h2 {
  margin: var(--sp-2) 0 var(--sp-2);
  font-size: clamp(23px, 4.4vw, 40px);
  line-height: 1.14;
  letter-spacing: -0.02em;
  max-width: 18em;
}

/* ---------- 时间轴 ---------- */
.page-about .ab-timeline {
  position: relative;
  background: linear-gradient(180deg, var(--ink-900), var(--ink-800) 40%, var(--ink-900));
}

.page-about .ab-side-note {
  display: none;
}

.page-about .ab-toolbar {
  position: relative;
}

.page-about .ab-filters {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 var(--sp-4);
}

.page-about .ab-track {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .ab-node {
  position: relative;
  display: grid;
  grid-template-columns: 28px minmax(0, 1fr);
  column-gap: var(--sp-2);
  padding-bottom: var(--sp-4);
}

.page-about .ab-node:last-child {
  padding-bottom: 0;
}

.page-about .ab-node::before {
  content: "";
  position: absolute;
  left: 13px;
  top: 22px;
  bottom: 0;
  width: 1px;
  background: linear-gradient(180deg, var(--ink-700), rgba(24, 35, 58, .15));
}

.page-about .ab-node:last-child::before {
  display: none;
}

.page-about .ab-node__dot {
  grid-column: 1;
  justify-self: center;
  width: 12px;
  height: 12px;
  margin-top: 8px;
  border-radius: 50%;
  background: var(--ink-900);
  border: 2px solid var(--mist-400);
  box-shadow: 0 0 0 4px rgba(140, 155, 181, .12);
  position: relative;
  z-index: 1;
}

.page-about .ab-node__dot--cyan {
  border-color: var(--ab-cn);
  box-shadow: 0 0 0 4px rgba(0, 229, 208, .12);
}

.page-about .ab-node__dot--gold {
  border-color: var(--ab-gd);
  box-shadow: 0 0 0 4px rgba(242, 193, 78, .14);
}

.page-about .ab-node__dot--orange {
  border-color: var(--ab-or);
  box-shadow: 0 0 0 4px rgba(255, 106, 31, .16);
}

.page-about .ab-node__body {
  grid-column: 2;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--sp-2);
  background: var(--ink-800);
  border: var(--line);
  border-radius: var(--radius);
  padding: var(--sp-3);
  transition: border-color .25s ease, transform .25s ease, background-color .25s ease;
}

.page-about .ab-node__body:hover {
  border-color: rgba(0, 229, 208, .5);
  transform: translateX(4px);
}

.page-about .ab-node__ver {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(34px, 8vw, 58px);
  font-weight: 700;
  line-height: .95;
  letter-spacing: -0.05em;
  color: rgba(140, 155, 181, .3);
}

.page-about .ab-node--v2 .ab-node__ver { color: rgba(0, 229, 208, .32); }
.page-about .ab-node--v3 .ab-node__ver { color: rgba(242, 193, 78, .32); }
.page-about .ab-node--v4 .ab-node__ver { color: rgba(255, 106, 31, .38); }

.page-about .ab-node__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--sp-2);
  margin-bottom: var(--sp-2);
}

.page-about .ab-node__main .st-h3 {
  margin: 0 0 var(--sp-2);
  font-size: clamp(18px, 2.6vw, 24px);
  line-height: 1.3;
}

.page-about .ab-node__main p {
  margin: 0;
  max-width: 40em;
  color: var(--paper-100);
}

.page-about .ab-chips {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: var(--sp-3) 0 0;
  padding: 0;
}

.page-about .ab-chips li {
  font-size: 12px;
  letter-spacing: .08em;
  padding: 4px 10px;
  border: 1px solid var(--ink-700);
  background: var(--ink-900);
  color: var(--mist-400);
  border-radius: var(--radius);
}

/* ---------- 排名带 ---------- */
.page-about .ab-rank {
  background: var(--teal-900);
  background-image: repeating-linear-gradient(135deg, rgba(242, 193, 78, .05) 0 2px, transparent 2px 16px);
  border-top: var(--line);
  border-bottom: var(--line);
}

.page-about .ab-rank__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-3);
  padding-top: var(--sp-4);
  padding-bottom: var(--sp-4);
}

.page-about .ab-rank__copy {
  min-width: min(100%, 320px);
  flex: 1 1 380px;
}

.page-about .ab-rank__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-1);
}

/* ---------- 团队 ---------- */
.page-about .ab-team__grid {
  display: grid;
  gap: var(--sp-4);
}

.page-about .ab-team__media .st-media {
  aspect-ratio: 4 / 3;
  overflow: hidden;
}

.page-about .ab-team__media .st-note {
  margin: var(--sp-2) 0 0;
}

.page-about .ab-roles {
  list-style: none;
  margin: var(--sp-4) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--ink-700);
  border: var(--line);
}

.page-about .ab-role {
  background: var(--ink-800);
  padding: var(--sp-3);
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr);
  grid-template-areas:
    "num name"
    "num text";
  column-gap: var(--sp-3);
  row-gap: 6px;
  align-items: start;
  transition: background-color .25s ease;
}

.page-about .ab-role:hover {
  background: #111c2f;
}

.page-about .ab-role__num {
  grid-area: num;
  font-size: clamp(28px, 5vw, 38px);
  line-height: 1;
  color: var(--ab-cn);
  align-self: center;
}

.page-about .ab-role:nth-child(2) .ab-role__num { color: var(--ab-or); }
.page-about .ab-role:nth-child(3) .ab-role__num { color: var(--ab-gd); }

.page-about .ab-role__name {
  grid-area: name;
  font-size: 16px;
  font-weight: 700;
  letter-spacing: .04em;
}

.page-about .ab-role__text {
  grid-area: text;
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--mist-400);
}

/* ---------- 观察员网络 ---------- */
.page-about .ab-network {
  background: linear-gradient(180deg, var(--ink-900), #0a1420 55%, var(--ink-900));
}

.page-about .ab-network__grid {
  display: grid;
  gap: var(--sp-4);
}

.page-about .ab-network__visual .st-media {
  aspect-ratio: 4 / 3;
  overflow: hidden;
}

.page-about .ab-map {
  margin: var(--sp-4) 0 0;
  padding: var(--sp-3);
  border: var(--line);
  background: var(--ink-800);
  border-radius: var(--radius);
}

.page-about .ab-map__svg {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .ab-map__links line {
  stroke: rgba(0, 229, 208, .22);
  stroke-width: 1;
}

.page-about .ab-map__hub {
  fill: var(--ab-cn);
}

.page-about .ab-map__node {
  fill: var(--ab-gd);
  transform-box: fill-box;
  transform-origin: center;
  transition: transform .2s ease, fill .2s ease;
}

.page-about .ab-map__node:hover {
  transform: scale(1.7);
  fill: var(--ab-mg);
}

.page-about .ab-map__labels text {
  fill: var(--mist-400);
  font-family: var(--font-sans);
  font-size: 11px;
  letter-spacing: .06em;
}

.page-about .ab-map figcaption {
  margin-top: var(--sp-2);
}

.page-about .ab-cities {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: var(--sp-3) 0 0;
  padding: 0;
}

.page-about .ab-city {
  font-size: 12px;
  letter-spacing: .1em;
  padding: 5px 10px;
  border: 1px solid var(--ink-700);
  background: var(--ink-800);
  color: var(--mist-400);
  border-radius: var(--radius);
}

.page-about .ab-city--hub {
  border-color: rgba(0, 229, 208, .5);
  color: var(--ab-cn);
  background: rgba(0, 229, 208, .06);
}

/* ---------- 三步复盘法 ---------- */
.page-about .ab-method {
  background: var(--ink-900);
}

.page-about .ab-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--ink-700);
  border: var(--line);
}

.page-about .ab-step {
  background: var(--ink-800);
  padding: var(--sp-3);
  border-top: 2px solid transparent;
  transition: background-color .25s ease;
}

.page-about .ab-step:nth-child(1) { border-top-color: var(--ab-cn); }
.page-about .ab-step:nth-child(2) { border-top-color: var(--ab-gd); background: var(--teal-900); }
.page-about .ab-step:nth-child(3) { border-top-color: var(--ab-mg); }

.page-about .ab-step:hover {
  background: #111c2f;
}

.page-about .ab-step:nth-child(2):hover {
  background: #073843;
}

.page-about .ab-step__no {
  display: block;
  font-size: 30px;
  line-height: 1;
  color: var(--mist-400);
  margin-bottom: var(--sp-2);
}

.page-about .ab-step:nth-child(1) .ab-step__no { color: var(--ab-cn); }
.page-about .ab-step:nth-child(2) .ab-step__no { color: var(--ab-gd); }
.page-about .ab-step:nth-child(3) .ab-step__no { color: var(--ab-mg); }

.page-about .ab-step .st-h3 {
  margin: 0 0 var(--sp-2);
  font-size: 19px;
  line-height: 1.3;
}

.page-about .ab-step p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--mist-400);
}

/* ---------- 合作生态 ---------- */
.page-about .ab-partners {
  background: var(--ink-900);
}

.page-about .ab-partners__grid {
  display: grid;
  gap: var(--sp-4);
}

.page-about .ab-plist {
  list-style: none;
  margin: var(--sp-4) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--ink-700);
  border: var(--line);
}

.page-about .ab-plist li {
  background: var(--ink-800);
  padding: var(--sp-3);
  display: grid;
  grid-template-columns: 60px minmax(0, 1fr);
  gap: var(--sp-2);
  align-items: baseline;
}

.page-about .ab-plist b {
  font-family: var(--font-mono);
  font-size: 26px;
  line-height: 1;
  color: var(--ab-cn);
  font-weight: 700;
}

.page-about .ab-plist li:nth-child(2) b { color: var(--ab-or); }
.page-about .ab-plist li:nth-child(3) b { color: var(--ab-gd); }
.page-about .ab-plist li:nth-child(4) b { color: var(--ab-mg); }

.page-about .ab-plist span {
  font-size: 15px;
  line-height: 1.7;
  color: var(--paper-100);
}

.page-about .ab-honors {
  position: relative;
  overflow: hidden;
  border: var(--line);
  border-radius: var(--radius);
  padding: var(--sp-4) var(--sp-3);
  background: linear-gradient(155deg, var(--teal-900), var(--ink-800) 70%);
}

.page-about .ab-honors::after {
  content: "";
  position: absolute;
  right: -40px;
  bottom: -40px;
  width: 200px;
  height: 200px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(242, 193, 78, .18), transparent 68%);
  pointer-events: none;
}

.page-about .ab-honors .st-kpi {
  margin: var(--sp-3) 0 var(--sp-2);
  color: var(--ab-gd);
}

.page-about .ab-honors__text {
  margin: 0 0 var(--sp-3);
  font-size: 15px;
  line-height: 1.75;
  color: var(--paper-100);
  max-width: 30em;
}

/* ---------- 加入与联络 ---------- */
.page-about .ab-join {
  background: linear-gradient(180deg, var(--ink-900), var(--teal-900));
  border-top: var(--line);
}

.page-about .ab-join__grid {
  display: grid;
  gap: var(--sp-4);
}

.page-about .ab-join__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-1);
  margin-top: var(--sp-4);
}

.page-about .ab-join__media .st-media {
  aspect-ratio: 16 / 9;
  overflow: hidden;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .ab-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 760px) {
  .page-about .ab-node__body {
    grid-template-columns: 160px minmax(0, 1fr);
    column-gap: var(--sp-4);
    align-items: start;
    padding: var(--sp-4);
  }

  .page-about .ab-node__ver {
    font-size: clamp(48px, 6vw, 72px);
  }

  .page-about .ab-team__grid {
    grid-template-columns: 5fr 7fr;
    gap: 48px;
    align-items: start;
  }

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

  .page-about .ab-step {
    padding: var(--sp-4) var(--sp-3);
  }
}

@media (min-width: 900px) {
  .page-about .ab-network__grid {
    grid-template-columns: 4fr 8fr;
    gap: 48px;
    align-items: start;
  }

  .page-about .ab-partners__grid {
    grid-template-columns: 7fr 5fr;
    gap: 48px;
    align-items: start;
  }

  .page-about .ab-join__grid {
    grid-template-columns: 6fr 6fr;
    gap: 48px;
    align-items: center;
  }

  .page-about .ab-node {
    grid-template-columns: 40px minmax(0, 1fr);
    column-gap: var(--sp-3);
  }

  .page-about .ab-node::before {
    left: 19px;
  }
}

@media (min-width: 1100px) {
  .page-about .ab-timeline {
    padding-left: 56px;
  }

  .page-about .ab-side-note {
    display: block;
    position: absolute;
    left: var(--gutter);
    top: clamp(40px, 7vw, 96px);
    writing-mode: vertical-rl;
    letter-spacing: .34em;
    font-size: 11px;
    color: var(--mist-400);
    height: 220px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-node__body,
  .page-about .ab-map__node,
  .page-about .ab-role,
  .page-about .ab-step {
    transition: none;
  }

  .page-about .ab-node__body:hover {
    transform: none;
  }
}