.page-about {
  --ab-cyan-soft: rgba(34, 224, 214, .12);
  --ab-orange-soft: rgba(255, 122, 26, .14);
  --ab-violet-soft: rgba(162, 56, 255, .16);
  --ab-gap: 24px;
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
  overflow: hidden;
  padding: 40px 0 48px;
  border-bottom: 1px solid var(--bb-line);
  background:
    radial-gradient(120% 90% at 82% -10%, rgba(34, 224, 214, .10), transparent 62%),
    radial-gradient(90% 70% at 6% 100%, rgba(162, 56, 255, .10), transparent 66%);
}

.page-about .ab-hero__grid {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(138, 148, 166, .09) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(138, 148, 166, .09) 1px, transparent 1px);
  background-size: 58px 58px;
  -webkit-mask-image: radial-gradient(115% 82% at 74% 4%, #000 24%, transparent 76%);
  mask-image: radial-gradient(115% 82% at 74% 4%, #000 24%, transparent 76%);
}

.page-about .ab-hero__glow {
  position: absolute;
  right: -140px;
  top: -120px;
  width: 420px;
  height: 420px;
  border-radius: 50%;
  pointer-events: none;
  background: radial-gradient(circle, rgba(255, 45, 110, .20), rgba(34, 224, 214, .06) 55%, transparent 72%);
  filter: blur(10px);
}

.page-about .ab-hero__inner {
  position: relative;
  z-index: 1;
}

.page-about .ab-hero__label {
  margin: 22px 0 14px;
}

.page-about .ab-hero__title {
  margin: 0 0 18px;
  max-width: 15ch;
}

.page-about .ab-hero__lead {
  margin: 0 0 26px;
  max-width: 60ch;
}

.page-about .ab-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 34px;
}

.page-about .ab-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--bb-line);
  border: 1px solid var(--bb-line);
  border-radius: var(--bb-radius);
  overflow: hidden;
}

.page-about .ab-stat {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 16px 16px 18px;
  background: var(--bb-panel);
  border-left: 2px solid transparent;
}

.page-about .ab-stat:nth-child(1) { border-left-color: var(--bb-cyan); }
.page-about .ab-stat:nth-child(2) { border-left-color: var(--bb-orange); }
.page-about .ab-stat:nth-child(3) { border-left-color: var(--bb-violet); }
.page-about .ab-stat:nth-child(4) { border-left-color: var(--bb-cyan); }

.page-about .ab-stat .bb-stat__value {
  font-size: 26px;
  line-height: 1.1;
  color: var(--bb-cyan);
}

.page-about .ab-stat:nth-child(2) .bb-stat__value { color: var(--bb-orange); }
.page-about .ab-stat:nth-child(3) .bb-stat__value { color: #C88BFF; }

.page-about .ab-stat .bb-stat__label {
  font-size: 13px;
  color: var(--bb-text-2);
  line-height: 1.4;
}

/* ---------- 两栏骨架 ---------- */
.page-about .ab-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--ab-gap);
  padding-top: 48px;
  padding-bottom: 56px;
}

/* ---------- 目录 ---------- */
.page-about .ab-toc {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  padding: 14px 0 18px;
  border-bottom: 1px solid var(--bb-line);
}

.page-about .ab-toc__cap {
  width: 100%;
  margin: 0 0 2px;
  font-size: 12px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--bb-steel);
}

.page-about .ab-toc a {
  font-size: 14px;
  color: var(--bb-text-2);
  text-decoration: none;
  padding: 4px 0;
  border-bottom: 2px solid transparent;
  transition: color .2s var(--bb-ease), border-color .2s var(--bb-ease);
}

.page-about .ab-toc a:hover,
.page-about .ab-toc a:focus-visible,
.page-about .ab-toc a.is-current {
  color: var(--bb-cyan);
  border-bottom-color: var(--bb-cyan);
}

/* ---------- 正文流 ---------- */
.page-about .ab-chapter {
  scroll-margin-top: 96px;
}

.page-about .ab-chapter + .ab-chapter {
  margin-top: 60px;
  padding-top: 44px;
  border-top: 1px solid var(--bb-line);
}

.page-about .ab-h2 {
  margin: 12px 0 16px;
  font-family: var(--bb-font-head);
  font-weight: 900;
  font-size: clamp(26px, 5.2vw, 40px);
  line-height: 1.14;
  letter-spacing: -.01em;
  color: var(--bb-text);
  transform: skewX(-2deg);
  transform-origin: left center;
}

.page-about .ab-p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.75;
  color: var(--bb-text-2);
  max-width: 68ch;
}

.page-about .ab-p a {
  color: var(--bb-cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 时间线 ---------- */
.page-about .ab-timeline {
  list-style: none;
  margin: 28px 0 0;
  padding: 0 0 0 34px;
  position: relative;
}

.page-about .ab-timeline::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 8px;
  bottom: 12px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--bb-cyan) 0%, var(--bb-violet) 52%, var(--bb-magenta) 74%, rgba(255, 45, 110, 0) 100%);
}

.page-about .ab-node {
  position: relative;
  padding-bottom: 26px;
}

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

.page-about .ab-node::before {
  content: "";
  position: absolute;
  left: -34px;
  top: 5px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--bb-ink);
  border: 3px solid var(--bb-cyan);
  box-shadow: 0 0 0 4px var(--ab-cyan-soft);
}

.page-about .ab-node:nth-child(2)::before { border-color: var(--bb-orange); box-shadow: 0 0 0 4px var(--ab-orange-soft); }
.page-about .ab-node:nth-child(3)::before { border-color: var(--bb-violet); box-shadow: 0 0 0 4px var(--ab-violet-soft); }
.page-about .ab-node:nth-child(4)::before { border-color: var(--bb-cyan); }
.page-about .ab-node:nth-child(5)::before { border-color: var(--bb-orange); box-shadow: 0 0 0 4px var(--ab-orange-soft); }
.page-about .ab-node:nth-child(6)::before { border-color: var(--bb-magenta); box-shadow: 0 0 0 4px rgba(255, 45, 110, .16); }

.page-about .ab-node__head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin: 0 0 6px;
}

.page-about .ab-node__title {
  font-family: var(--bb-font-head);
  font-weight: 800;
  font-size: 17px;
  color: var(--bb-text);
}

.page-about .ab-node__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--bb-text-2);
  max-width: 62ch;
}

/* ---------- 配图 ---------- */
.page-about .ab-figure {
  margin: 22px 0;
  position: relative;
}

.page-about .ab-figure__cap {
  margin-top: 10px;
  font-size: 13px;
  color: var(--bb-steel);
  letter-spacing: .02em;
}

/* ---------- 团队角色卡 ---------- */
.page-about .ab-roles {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 24px;
}

.page-about .ab-role {
  position: relative;
  padding: 18px 18px 16px;
  border-radius: var(--bb-radius);
  border-left: 3px solid var(--bb-orange);
  transition: background .25s var(--bb-ease), transform .25s var(--bb-ease), box-shadow .25s var(--bb-ease);
}

.page-about .ab-role:hover,
.page-about .ab-role:focus-within {
  background: var(--bb-panel-2);
  transform: translateY(-2px);
  box-shadow: 0 14px 30px rgba(0, 0, 0, .38);
}

.page-about .ab-role:nth-child(2) { border-left-color: var(--bb-cyan); }
.page-about .ab-role:nth-child(3) { border-left-color: var(--bb-violet); }
.page-about .ab-role:nth-child(4) { border-left-color: var(--bb-magenta); }

.page-about .ab-role__tag {
  margin: 0 0 8px;
}

.page-about .ab-role__name {
  margin: 0 0 8px;
  font-family: var(--bb-font-head);
  font-weight: 800;
  font-size: 18px;
  color: var(--bb-text);
}

.page-about .ab-role__line {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--bb-text-2);
}

.page-about .ab-role__more {
  margin: 0;
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  font-size: 14px;
  line-height: 1.7;
  color: var(--bb-steel);
  transition: max-height .32s var(--bb-ease), opacity .28s var(--bb-ease), margin-top .32s var(--bb-ease);
}

.page-about .ab-role:hover .ab-role__more,
.page-about .ab-role:focus-within .ab-role__more {
  max-height: 160px;
  opacity: 1;
  margin-top: 10px;
}

.page-about .ab-role__more a {
  color: var(--bb-cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 数据桩 ---------- */
.page-about .ab-cols3 {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin: 22px 0;
}

.page-about .ab-fact {
  padding: 16px;
  border-radius: var(--bb-radius);
  border-top: 2px solid var(--bb-violet);
}

.page-about .ab-fact:nth-child(2) { border-top-color: var(--bb-cyan); }
.page-about .ab-fact:nth-child(3) { border-top-color: var(--bb-orange); }

.page-about .ab-fact__num {
  margin: 0 0 6px;
  font-size: 30px;
  line-height: 1;
  color: var(--bb-text);
}

.page-about .ab-fact:nth-child(2) .ab-fact__num { color: var(--bb-cyan); }
.page-about .ab-fact:nth-child(3) .ab-fact__num { color: var(--bb-orange); }

.page-about .ab-fact__txt {
  margin: 0;
  font-size: 14px;
  line-height: 1.55;
  color: var(--bb-text-2);
}

/* ---------- 服务场景 ---------- */
.page-about .ab-scenes {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  margin-top: 26px;
  border-top: 1px solid var(--bb-line);
}

.page-about .ab-scene {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  grid-template-areas: "idx body" "go go";
  gap: 10px 12px;
  padding: 20px 4px 18px;
  text-decoration: none;
  border-bottom: 1px solid var(--bb-line);
  transition: background .25s var(--bb-ease), padding-left .25s var(--bb-ease);
}

.page-about .ab-scene:hover,
.page-about .ab-scene:focus-visible {
  background: linear-gradient(90deg, rgba(34, 224, 214, .07), transparent 70%);
  padding-left: 12px;
}

.page-about .ab-scene__idx {
  grid-area: idx;
  font-size: 15px;
  color: var(--bb-steel);
  padding-top: 2px;
}

.page-about .ab-scene__body {
  grid-area: body;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .ab-scene__tag {
  margin: 0;
}

.page-about .ab-scene__name {
  font-family: var(--bb-font-head);
  font-weight: 800;
  font-size: 18px;
  line-height: 1.35;
  color: var(--bb-text);
}

.page-about .ab-scene__desc {
  font-size: 15px;
  line-height: 1.7;
  color: var(--bb-text-2);
  max-width: 62ch;
}

.page-about .ab-scene__go {
  grid-area: go;
  justify-self: end;
  align-self: end;
  font-size: 13px;
  letter-spacing: .05em;
  color: var(--bb-cyan);
}

/* ---------- 发展节奏：图文错落 ---------- */
.page-about .ab-media-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  margin-top: 20px;
}

.page-about .ab-media-split__fig {
  margin: 0;
}

.page-about .ab-checklist {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .ab-checklist li {
  position: relative;
  padding-left: 20px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--bb-text-2);
}

.page-about .ab-checklist li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 10px;
  height: 2px;
  background: var(--bb-orange);
}

/* ---------- 工作方式 ---------- */
.page-about .ab-methods {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 24px;
}

.page-about .ab-method {
  padding: 20px 18px;
  border-radius: var(--bb-radius);
}

.page-about .ab-method__idx {
  margin: 0 0 10px;
  font-size: 13px;
  letter-spacing: .22em;
  color: var(--bb-cyan);
}

.page-about .ab-method:nth-child(2) .ab-method__idx { color: var(--bb-orange); }
.page-about .ab-method:nth-child(3) .ab-method__idx { color: var(--bb-violet); }

.page-about .ab-method__name {
  margin: 0 0 10px;
  font-family: var(--bb-font-head);
  font-weight: 800;
  font-size: 18px;
  color: var(--bb-text);
}

.page-about .ab-method__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--bb-text-2);
}

.page-about .ab-method__text a {
  color: var(--bb-cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 信任条 ---------- */
.page-about .ab-trust {
  margin-top: 28px;
  padding: 20px 18px;
  border-radius: var(--bb-radius);
  border: 1px dashed var(--bb-line-violet);
  background: linear-gradient(135deg, rgba(162, 56, 255, .10), rgba(34, 224, 214, .06));
}

.page-about .ab-trust__head {
  margin: 0 0 14px;
  font-family: var(--bb-font-head);
  font-weight: 800;
  font-size: 16px;
  color: var(--bb-text);
}

.page-about .ab-trust__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px 16px;
}

.page-about .ab-trust__list li {
  font-size: 14px;
  line-height: 1.5;
  color: var(--bb-text-2);
}

.page-about .ab-trust__list .bb-mono {
  color: var(--bb-cyan);
  margin-right: 4px;
}

/* ---------- 底部 CTA ---------- */
.page-about .ab-cta {
  border-top: 1px solid var(--bb-line);
  background:
    radial-gradient(90% 120% at 88% 0%, rgba(255, 122, 26, .12), transparent 62%),
    var(--bb-panel);
}

.page-about .ab-cta__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 20px;
  padding-top: 40px;
  padding-bottom: 44px;
}

.page-about .ab-cta__title {
  margin: 0 0 10px;
  font-family: var(--bb-font-head);
  font-weight: 900;
  font-size: clamp(22px, 4.4vw, 32px);
  line-height: 1.2;
  color: var(--bb-text);
  transform: skewX(-2deg);
  transform-origin: left center;
}

.page-about .ab-cta__desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--bb-text-2);
  max-width: 60ch;
}

.page-about .ab-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

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

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

  .page-about .ab-cols3 {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

  .page-about .ab-scene {
    grid-template-columns: 40px minmax(0, 1fr) auto;
    grid-template-areas: "idx .page-about go";
    align-items: center;
  }

  .page-about .ab-scene__go {
    align-self: center;
  }

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

/* ---------- 桌面 ---------- */
@media (min-width: 1000px) {
  .page-about .ab-hero {
    padding: 56px 0 64px;
  }

  .page-about .ab-split {
    grid-template-columns: 208px minmax(0, 1fr);
    gap: 56px;
    padding-top: 64px;
    padding-bottom: 72px;
  }

  .page-about .ab-toc {
    position: sticky;
    top: 104px;
    display: flex;
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 2px;
    padding: 0 0 0 14px;
    border-bottom: 0;
    border-left: 1px solid var(--bb-line);
    align-self: start;
  }

  .page-about .ab-toc a {
    padding: 7px 0;
    border-bottom: 0;
    border-left: 2px solid transparent;
    margin-left: -16px;
    padding-left: 14px;
  }

  .page-about .ab-toc a.is-current {
    border-left-color: var(--bb-cyan);
    background: linear-gradient(90deg, rgba(34, 224, 214, .10), transparent 82%);
  }

  .page-about .ab-chapter + .ab-chapter {
    margin-top: 74px;
    padding-top: 56px;
  }

  .page-about .ab-media-split {
    grid-template-columns: minmax(0, 1fr) 300px;
    gap: 40px;
    align-items: start;
  }

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

  .page-about .ab-cta__inner {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 40px;
    padding-top: 52px;
    padding-bottom: 56px;
  }

  .page-about .ab-trust__list {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }
}

@media (min-width: 1200px) {
  .page-about .ab-roles {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-role,
  .page-about .ab-role__more,
  .page-about .ab-scene,
  .page-about .ab-toc a {
    transition: none;
  }
}