.page-about {
  --ab-gutter: 32px;
  background: var(--ink);
  color: var(--silver);
  font-family: var(--font-body);
  line-height: 1.75;
  overflow-x: clip;
}

.page-about img {
  max-width: 100%;
  height: auto;
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
  padding-block: clamp(18px, 3vw, 36px) clamp(48px, 7vw, 92px);
  background:
    radial-gradient(120% 90% at 88% 0%, rgba(127, 210, 74, .10), transparent 58%),
    radial-gradient(85% 65% at 0% 100%, rgba(217, 85, 47, .09), transparent 62%),
    var(--ink);
  border-bottom: var(--bw) solid var(--rock);
  overflow: hidden;
}

.page-about .ab-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(198, 204, 199, .06) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(198, 204, 199, .06) 1px, transparent 1px);
  background-size: 56px 56px;
  -webkit-mask-image: linear-gradient(to bottom, #000 0%, transparent 78%);
  mask-image: linear-gradient(to bottom, #000 0%, transparent 78%);
  pointer-events: none;
}

.page-about .ab-hero > .wrap {
  position: relative;
  z-index: 1;
}

.page-about .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0 0 clamp(18px, 2.6vw, 30px);
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--cold);
}

.page-about .breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  margin-right: 8px;
  color: var(--rock);
}

.page-about .breadcrumb__link {
  color: var(--cold);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .16s var(--ease), border-color .16s var(--ease);
}

.page-about .breadcrumb__link:hover {
  color: var(--green);
  border-bottom-color: var(--green);
}

.page-about .breadcrumb__current {
  color: var(--silver);
}

.page-about .ab-hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(26px, 3.4vw, 44px);
}

.page-about .ab-hero__eyebrow {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--green);
}

.page-about .ab-hero__title {
  margin: 0 0 20px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.95rem, 5.6vw, 4.1rem);
  line-height: 1.06;
  letter-spacing: -.022em;
  color: var(--paper);
}

.page-about .ab-hero__title em {
  font-style: normal;
  display: inline-block;
  color: var(--green);
}

.page-about .ab-hero__lede {
  margin: 0 0 clamp(24px, 3vw, 34px);
  max-width: 64ch;
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--silver);
}

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

.page-about .ab-hero__aside {
  display: grid;
  gap: 0;
  border-top: var(--bw) solid var(--rock);
  align-self: start;
}

.page-about .ab-key {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.65fr);
  gap: 6px 16px;
  align-items: baseline;
  padding: 16px 0;
  border-bottom: var(--bw) solid var(--rock);
}

.page-about .ab-key__value {
  margin: 0;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.5rem, 3vw, 1.95rem);
  line-height: 1;
  color: var(--paper);
  letter-spacing: -.02em;
}

.page-about .ab-key__value span {
  margin-left: 5px;
  font-size: .46em;
  letter-spacing: .04em;
  color: var(--green);
}

.page-about .ab-key__label {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--cold);
}

.page-about .ab-hero__code {
  display: none;
}

/* ---------- 时间轴主体 ---------- */
.page-about .ab-track {
  position: relative;
  padding-left: var(--ab-gutter);
  padding-block: clamp(44px, 6vw, 88px);
}

.page-about .ab-track::before {
  content: "";
  position: absolute;
  left: 7px;
  top: clamp(56px, 7vw, 104px);
  bottom: clamp(56px, 7vw, 104px);
  width: 2px;
  background: var(--rock);
  opacity: .9;
}

.page-about .ab-sec {
  position: relative;
  padding-bottom: clamp(52px, 7vw, 96px);
}

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

.page-about .ab-sec__dot {
  position: absolute;
  top: 6px;
  left: calc(var(--ab-gutter) * -1);
  width: 16px;
  height: 16px;
  background: var(--ink);
  border: var(--bw) solid var(--green);
  box-shadow: 4px 4px 0 var(--deep-green);
  transition: background .18s var(--ease), box-shadow .18s var(--ease);
  z-index: 2;
}

.page-about .ab-sec:hover .ab-sec__dot {
  background: var(--green);
  box-shadow: 4px 4px 0 var(--orange);
}

.page-about .ab-sec--paper {
  padding: clamp(24px, 3.4vw, 46px) clamp(20px, 3vw, 42px);
  background: var(--paper);
  color: var(--ink);
  box-shadow:
    inset 0 0 0 2px var(--silver),
    inset 0 -6px 0 rgba(217, 85, 47, .2);
}

.page-about .ab-sec--paper .ab-sec__dot {
  background: var(--ink);
  border-color: var(--orange);
  box-shadow: 4px 4px 0 var(--clay);
}

/* ---------- 章节标题 ---------- */
.page-about .ab-head {
  margin-bottom: clamp(20px, 3vw, 32px);
}

.page-about .ab-head__stage {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--cold);
}

.page-about .ab-head__stage::before {
  content: "";
  width: 20px;
  height: 2px;
  background: var(--orange);
  flex: none;
}

.page-about .ab-head__stage .mono {
  color: var(--orange);
  font-weight: 700;
}

.page-about .ab-head__title {
  margin: 0 0 14px;
  max-width: 26ch;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.45rem, 3.2vw, 2.25rem);
  line-height: 1.2;
  letter-spacing: -.012em;
  color: var(--paper);
}

.page-about .ab-head__lede {
  margin: 0;
  max-width: 68ch;
  font-size: 15px;
  line-height: 1.9;
  color: var(--cold);
}

.page-about .ab-sec--paper .ab-head__stage {
  color: var(--rock);
}

.page-about .ab-sec--paper .ab-head__stage .mono {
  color: var(--orange);
}

.page-about .ab-sec--paper .ab-head__title {
  color: var(--ink);
}

.page-about .ab-sec--paper .ab-head__lede {
  color: var(--rock);
}

/* ---------- 场景卡片 ---------- */
.page-about .ab-cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--gap);
}

.page-about .ab-card {
  padding: 22px 20px 24px;
  background: var(--ink-2);
  border: var(--bw) solid var(--rock);
  transition: border-color .18s var(--ease), box-shadow .18s var(--ease);
}

.page-about .ab-card:hover,
.page-about .ab-card:focus-within {
  border-color: var(--green);
  box-shadow: 6px 6px 0 var(--deep-green);
}

.page-about .ab-card__idx {
  margin: 0 0 10px;
  font-size: 12px;
  letter-spacing: .22em;
  color: var(--orange);
}

.page-about .ab-card__title {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.48;
  color: var(--paper);
}

.page-about .ab-card__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--cold);
}

/* ---------- 链接 ---------- */
.page-about .ab-link {
  display: inline-block;
  padding-bottom: 3px;
  color: var(--green);
  text-decoration: none;
  border-bottom: 1px solid var(--rock);
  transition: border-color .18s var(--ease);
}

.page-about .ab-link::after {
  content: " →";
  font-family: var(--font-mono);
}

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

.page-about .ab-sec--paper .ab-link {
  color: var(--deep-green);
  border-bottom-color: rgba(46, 107, 58, .4);
}

.page-about .ab-sec--paper .ab-link:hover {
  border-bottom-color: var(--deep-green);
}

.page-about .ab-more {
  margin: clamp(20px, 3vw, 30px) 0 0;
  font-size: 14px;
}

/* ---------- 分栏 ---------- */
.page-about .ab-sec__body--split {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 3.4vw, 46px);
}

/* ---------- 指标条 ---------- */
.page-about .ab-meter {
  margin: clamp(18px, 2.4vw, 26px) 0 0;
  padding: 0;
  list-style: none;
  border-top: var(--bw) solid var(--rock);
}

.page-about .ab-meter__item {
  display: grid;
  grid-template-columns: 1fr;
  gap: 6px;
  padding: 16px 0;
  border-bottom: var(--bw) solid var(--rock);
  transition: border-bottom-color .18s var(--ease);
}

.page-about .ab-meter__item:hover {
  border-bottom-color: var(--green);
}

.page-about .ab-meter__num {
  font-size: clamp(1.6rem, 3vw, 2.1rem);
  font-weight: 700;
  line-height: 1;
  color: var(--paper);
  letter-spacing: -.02em;
}

.page-about .ab-meter__unit {
  margin-left: 4px;
  font-size: .42em;
  color: var(--cold);
}

.page-about .ab-meter__txt {
  font-size: 14px;
  line-height: 1.78;
  color: var(--cold);
}

/* ---------- 图片容器 ---------- */
.page-about .ab-figure {
  margin: clamp(24px, 3.4vw, 40px) 0 0;
  background: var(--ink-2);
  box-shadow: inset 0 0 0 2px var(--rock);
}

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

.page-about .media-frame__cap {
  padding: 12px 16px;
  box-shadow: inset 0 2px 0 var(--rock);
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--cold);
}

.page-about .ab-figure--paper {
  background: #e3e0d7;
  box-shadow: inset 0 0 0 2px var(--silver);
}

.page-about .ab-figure--paper .media-frame__cap {
  box-shadow: inset 0 2px 0 var(--silver);
  color: var(--rock);
}

.page-about .ab-figure--band {
  margin-top: clamp(20px, 3vw, 34px);
}

/* ---------- 编辑流程 ---------- */
.page-about .ab-flow {
  margin: clamp(24px, 3vw, 36px) 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
}

.page-about .ab-flow__step {
  position: relative;
  padding: 22px 20px 24px;
  background: var(--rock);
  color: var(--silver);
  outline: none;
  transition: box-shadow .18s var(--ease), transform .18s var(--ease);
}

.page-about .ab-flow__step:nth-child(2) {
  background: var(--deep-green);
  color: var(--paper);
}

.page-about .ab-flow__step:nth-child(3) {
  background: var(--green);
  color: var(--ink);
}

.page-about .ab-flow__step:hover,
.page-about .ab-flow__step:focus-visible {
  box-shadow: 6px 6px 0 var(--orange);
}

.page-about .ab-flow__idx {
  display: block;
  margin-bottom: 12px;
  font-size: 11px;
  letter-spacing: .3em;
  opacity: .75;
}

.page-about .ab-flow__title {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.42;
}

.page-about .ab-flow__text {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.78;
  opacity: .9;
}

/* ---------- 列表 ---------- */
.page-about .ab-list {
  margin: clamp(16px, 2.2vw, 24px) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-list li {
  position: relative;
  margin: 0 0 12px;
  padding-left: 22px;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--cold);
}

.page-about .ab-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .78em;
  width: 10px;
  height: 2px;
  background: var(--orange);
}

/* ---------- 数据块 ---------- */
.page-about .ab-figures {
  display: grid;
  gap: 0;
  border-top: var(--bw) solid var(--rock);
  align-self: start;
}

.page-about .ab-metric {
  padding: 18px 0;
  border-bottom: var(--bw) solid var(--rock);
  transition: border-bottom-color .18s var(--ease);
}

.page-about .ab-metric:hover {
  border-bottom-color: var(--orange);
}

.page-about .ab-metric__num {
  margin: 0 0 6px;
  font-size: clamp(1.7rem, 3vw, 2.3rem);
  font-weight: 700;
  line-height: 1;
  color: var(--paper);
  letter-spacing: -.02em;
}

.page-about .ab-metric__num span {
  margin-left: 4px;
  font-size: .42em;
  color: var(--green);
}

.page-about .ab-metric__label {
  margin: 0;
  font-size: 13px;
  line-height: 1.72;
  color: var(--cold);
}

/* ---------- 发展节点 ---------- */
.page-about .ab-phase {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-phase__item {
  position: relative;
  padding: 18px 0 18px 20px;
  border-bottom: var(--bw) solid var(--rock);
}

.page-about .ab-phase__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 25px;
  width: 8px;
  height: 8px;
  background: var(--rock);
  transition: background .18s var(--ease);
}

.page-about .ab-phase__item:hover::before {
  background: var(--green);
}

.page-about .ab-phase__tag {
  margin: 0 0 8px;
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--orange);
}

.page-about .ab-phase__text {
  margin: 0;
  max-width: 74ch;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--cold);
}

/* ---------- 服务覆盖 ---------- */
.page-about .ab-svc {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  border-top: var(--bw) solid var(--silver);
}

.page-about .ab-svc__item {
  padding: 18px 0;
  border-bottom: var(--bw) solid var(--silver);
}

.page-about .ab-svc__num {
  margin: 0 0 8px;
  font-size: clamp(1.8rem, 3.4vw, 2.5rem);
  font-weight: 700;
  line-height: 1;
  color: var(--ink);
  letter-spacing: -.02em;
}

.page-about .ab-svc__num span {
  margin-left: 4px;
  font-size: .38em;
  color: var(--deep-green);
}

.page-about .ab-svc__txt {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--rock);
}

.page-about .ab-tail {
  display: grid;
  gap: 18px;
  margin-top: clamp(24px, 3vw, 36px);
  padding: clamp(20px, 2.8vw, 30px);
  background: var(--clay);
  box-shadow: inset 0 0 0 2px var(--orange);
}

.page-about .ab-tail__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--ink);
}

.page-about .ab-tail__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

/* ---------- 断点 ---------- */
@media (min-width: 560px) {
  .page-about .ab-meter__item {
    grid-template-columns: 148px minmax(0, 1fr);
    gap: 20px;
    align-items: center;
  }

  .page-about .ab-key {
    grid-template-columns: minmax(0, 130px) minmax(0, 1fr);
    align-items: center;
  }
}

@media (min-width: 760px) {
  .page-about .ab-cards {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    align-items: start;
  }

  .page-about .ab-card:nth-child(2) {
    margin-top: 20px;
  }

  .page-about .ab-card:nth-child(3) {
    margin-top: 40px;
  }

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

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

  .page-about .ab-svc__item:nth-child(odd) {
    padding-right: 20px;
  }

  .page-about .ab-svc__item:nth-child(even) {
    padding-left: 20px;
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero__lede,
  .page-about .ab-head__lede {
    font-size: 16px;
  }

  .page-about .ab-sec__body--split {
    grid-template-columns: minmax(0, 1fr) minmax(0, .82fr);
    align-items: start;
  }

  .page-about .ab-sec__body--split > .ab-figure {
    margin-top: 0;
  }

  .page-about .ab-phase__item {
    display: grid;
    grid-template-columns: 210px minmax(0, 1fr);
    gap: 6px 28px;
    align-items: start;
  }

  .page-about .ab-phase__tag {
    margin: 4px 0 0;
  }

  .page-about .ab-tail {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 30px;
  }
}

@media (min-width: 1000px) {
  .page-about {
    --ab-gutter: 56px;
  }

  .page-about .ab-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: start;
  }

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

  .page-about .ab-svc__item:nth-child(odd),
  .page-about .ab-svc__item:nth-child(even) {
    padding-inline: 20px;
  }

  .page-about .ab-svc__item:first-child {
    padding-left: 0;
  }

  .page-about .ab-svc__item:last-child {
    padding-right: 0;
  }
}

@media (min-width: 1200px) {
  .page-about .ab-hero__code {
    display: block;
    position: absolute;
    top: clamp(104px, 11vw, 168px);
    right: clamp(8px, 1.6vw, 20px);
    writing-mode: vertical-rl;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: .36em;
    color: var(--cold);
    opacity: .55;
    pointer-events: none;
    z-index: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition-duration: .01ms !important;
  }
}