.page-about {
  --ab-rail-w: 220px;
  --ab-ink: var(--ink-900);
  --ab-line: var(--rule-300);
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumbs {
  padding: 18px 0 0;
}

.page-about .breadcrumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted-600);
}

.page-about .breadcrumbs__item + .breadcrumbs__item::before {
  content: "/";
  margin-right: 8px;
  color: var(--rule-300);
}

.page-about .breadcrumbs a {
  color: var(--muted-600);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--t-fast) var(--ease), border-color var(--t-fast) var(--ease);
}

.page-about .breadcrumbs a:hover,
.page-about .breadcrumbs a:focus-visible {
  color: var(--brand-orange);
  border-bottom-color: var(--brand-orange);
}

/* ---------- 框景首屏 ---------- */
.page-about .ab-hero {
  padding: 22px 0 0;
}

.page-about .ab-hero__frame {
  position: relative;
  overflow: hidden;
  padding: 42px 22px 52px;
  color: var(--paper-050);
  border: 1px solid var(--ab-ink);
  background:
    radial-gradient(130% 150% at 88% 4%, rgba(255, 90, 31, 0.3) 0%, rgba(255, 90, 31, 0) 54%),
    linear-gradient(160deg, #121a2e 0%, var(--ink-900) 62%);
}

.page-about .ab-hero__frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    115deg,
    rgba(247, 243, 236, 0.09) 0 1px,
    transparent 1px 15px
  );
  opacity: 0.7;
  -webkit-mask-image: linear-gradient(200deg, #000 0%, transparent 64%);
  mask-image: linear-gradient(200deg, #000 0%, transparent 64%);
}

.page-about .ab-hero__eyebrow {
  position: relative;
  z-index: 1;
  margin: 0 0 16px;
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--volt-400);
}

.page-about .ab-hero__title {
  position: relative;
  z-index: 1;
  margin: 0;
  max-width: 18em;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(30px, 7.6vw, 58px);
  line-height: 1.07;
  letter-spacing: -0.02em;
}

.page-about .ab-hero__title em {
  font-style: normal;
  color: var(--brand-orange);
  background: linear-gradient(transparent 62%, rgba(255, 90, 31, 0.24) 62%);
}

.page-about .ab-hero__lead {
  position: relative;
  z-index: 1;
  margin: 20px 0 0;
  max-width: 44em;
  font-size: 16px;
  line-height: 1.8;
  color: rgba(247, 243, 236, 0.8);
}

.page-about .ab-hero__scale {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 9px;
  background-image: repeating-linear-gradient(
    90deg,
    var(--rule-300) 0 1px,
    transparent 1px 22px
  );
  opacity: 0.32;
}

/* ---------- 主体栅格 ---------- */
.page-about .ab-body {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 44px var(--gutter) 64px;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
  align-items: start;
}

.page-about .ab-flow {
  min-width: 0;
}

/* ---------- 侧边目录 ---------- */
.page-about .ab-rail {
  margin: 0 calc(var(--gutter) * -1);
  padding: 0 var(--gutter);
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

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

.page-about .rail__title {
  display: none;
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--muted-600);
}

.page-about .rail__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  white-space: nowrap;
}

.page-about .rail__item {
  flex: 0 0 auto;
}

.page-about .rail__link {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 8px 12px;
  font-size: 13px;
  font-weight: 600;
  color: var(--ink-900);
  text-decoration: none;
  background: var(--paper-100);
  border: 1px solid var(--ab-line);
  transition: border-color var(--t-fast) var(--ease), color var(--t-fast) var(--ease);
}

.page-about .rail__no {
  font-size: 11px;
  color: var(--muted-600);
}

.page-about .rail__link:hover,
.page-about .rail__link:focus-visible {
  border-color: var(--brand-orange);
  color: var(--brand-orange);
}

.page-about .rail__link[aria-current="true"] {
  border-color: var(--brand-orange);
  background: var(--orange-200);
  color: var(--ink-900);
}

.page-about .rail__link[aria-current="true"] .rail__no {
  color: var(--brand-orange);
}

/* ---------- 章节通用 ---------- */
.page-about .ab-sec {
  padding: 34px 0;
  border-top: 1px solid var(--ab-line);
}

.page-about .ab-sec:first-child {
  padding-top: 0;
  border-top: 0;
}

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

.page-about .ab-index {
  margin: 0 0 10px;
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--brand-orange);
}

.page-about .ab-title {
  margin: 0;
  max-width: 22em;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(23px, 5vw, 34px);
  line-height: 1.18;
  letter-spacing: -0.015em;
  color: var(--ink-900);
}

.page-about .ab-title::after {
  content: "";
  display: block;
  width: 64px;
  height: 5px;
  margin-top: 14px;
  background: var(--brand-orange);
}

.page-about .ab-lead {
  margin: 16px 0 0;
  max-width: 44em;
  font-size: 16px;
  line-height: 1.78;
  color: var(--muted-600);
}

/* ---------- 图片容器 ---------- */
.page-about .ab-figure {
  position: relative;
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--ab-line);
  background: var(--ink-700);
}

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

.page-about .ab-figure figcaption {
  padding: 10px 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: var(--muted-600);
  background: var(--paper-100);
  border-top: 1px solid var(--ab-line);
}

/* ---------- 01 业务线 ---------- */
.page-about .ab-roles {
  display: grid;
  gap: 22px;
}

.page-about .ab-roles__cards {
  display: grid;
  gap: 14px;
}

.page-about .ab-role {
  position: relative;
  padding: 20px 20px 20px 84px;
  background: var(--paper-050);
  border: 1px solid var(--ab-line);
  box-shadow: var(--shadow-card);
  transition: transform var(--t-fast) var(--ease), box-shadow var(--t-fast) var(--ease),
    border-color var(--t-fast) var(--ease);
}

.page-about .ab-role:hover,
.page-about .ab-role:focus-within {
  transform: translateY(-2px);
  border-color: var(--brand-orange);
  box-shadow: var(--shadow-card-hover);
}

.page-about .ab-role__num {
  position: absolute;
  left: 20px;
  top: 18px;
  width: 50px;
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--brand-orange);
}

.page-about .ab-role__title {
  margin: 10px 0 8px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ink-900);
}

.page-about .ab-role__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--muted-600);
}

.page-about .ab-roles__figure img {
  min-height: 200px;
}

/* ---------- 02 标准与复核 ---------- */
.page-about .ab-stds {
  display: grid;
  gap: 24px;
}

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

.page-about .ab-std {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr);
  gap: 4px 12px;
  padding: 16px 0;
  border-bottom: 1px solid var(--ab-line);
}

.page-about .ab-std:first-child {
  border-top: 1px solid var(--ab-line);
}

.page-about .ab-std__no {
  grid-row: span 2;
  padding-top: 3px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--brand-orange);
}

.page-about .ab-std__title {
  margin: 0;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--ink-900);
}

.page-about .ab-std__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--muted-600);
}

/* ---------- 03 时间轴 ---------- */
.page-about .ab-tl {
  position: relative;
  margin: 0;
  padding: 0 0 0 30px;
  list-style: none;
}

.page-about .ab-tl::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 10px;
  width: 2px;
  background: linear-gradient(
    180deg,
    var(--brand-orange) 0%,
    var(--brand-orange) 22%,
    var(--rule-300) 58%,
    var(--rule-300) 100%
  );
}

.page-about .ab-tl__item {
  position: relative;
  padding: 0 0 30px;
}

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

.page-about .ab-tl__dot {
  position: absolute;
  left: -30px;
  top: 4px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--paper-050);
  border: 2px solid var(--brand-orange);
  box-shadow: 0 0 0 3px var(--paper-050);
}

.page-about .ab-tl__item:not(:first-child) .ab-tl__dot {
  border-color: var(--rule-300);
}

.page-about .ab-tl__year {
  margin: 0 0 4px;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--brand-orange);
}

.page-about .ab-tl__title {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ink-900);
}

.page-about .ab-tl__text {
  margin: 0;
  max-width: 42em;
  font-size: 15px;
  line-height: 1.78;
  color: var(--muted-600);
}

/* ---------- 斜切分隔 ---------- */
.page-about .ab-slant {
  height: 24px;
  margin: 6px 0;
  background-image: repeating-linear-gradient(
    102deg,
    var(--brand-orange) 0 3px,
    transparent 3px 16px
  );
  opacity: 0.34;
  -webkit-mask-image: linear-gradient(90deg, #000 0%, transparent 78%);
  mask-image: linear-gradient(90deg, #000 0%, transparent 78%);
}

/* ---------- 04 服务规模 ---------- */
.page-about .ab-scale {
  position: relative;
  overflow: hidden;
  padding: 34px 22px 30px;
  color: var(--paper-050);
  background: var(--ink-900);
  border: 1px solid var(--ink-900);
}

.page-about .ab-scale::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    135deg,
    rgba(255, 90, 31, 0.16) 0 2px,
    transparent 2px 18px
  );
  opacity: 0.55;
  -webkit-mask-image: linear-gradient(120deg, #000 0%, transparent 72%);
  mask-image: linear-gradient(120deg, #000 0%, transparent 72%);
}

.page-about .ab-scale > * {
  position: relative;
  z-index: 1;
}

.page-about .ab-index--onDark {
  color: var(--volt-400);
}

.page-about .ab-title--onDark {
  color: var(--paper-050);
}

.page-about .ab-lead--onDark {
  color: rgba(247, 243, 236, 0.72);
}

.page-about .ab-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px 16px;
  margin-top: 28px;
}

.page-about .ab-stat__value {
  display: block;
  font-size: clamp(26px, 6vw, 40px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--paper-050);
}

.page-about .ab-stat__value em {
  font-style: normal;
  font-size: 0.5em;
  margin-left: 3px;
  color: var(--brand-orange);
}

.page-about .ab-stat__label {
  display: block;
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.55;
  color: rgba(247, 243, 236, 0.68);
}

.page-about .ab-scale__note {
  margin: 26px 0 0;
  padding-top: 16px;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: rgba(247, 243, 236, 0.5);
  border-top: 1px solid rgba(247, 243, 236, 0.16);
}

/* ---------- 05 陕西支持 ---------- */
.page-about .ab-shx {
  display: grid;
  gap: 24px;
}

.page-about .ab-shx__list {
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-shx__item {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  gap: 12px;
  padding: 11px 0;
  font-size: 15px;
  line-height: 1.6;
  color: var(--ink-900);
  border-bottom: 1px solid var(--ab-line);
}

.page-about .ab-shx__item:first-child {
  border-top: 1px solid var(--ab-line);
}

.page-about .ab-shx__k {
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted-600);
  padding-top: 4px;
}

.page-about .ab-shx__item a {
  color: var(--ink-900);
  text-decoration: none;
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.02em;
  word-break: break-all;
  border-bottom: 1px solid var(--rule-300);
  transition: color var(--t-fast) var(--ease), border-color var(--t-fast) var(--ease);
}

.page-about .ab-shx__item a:hover,
.page-about .ab-shx__item a:focus-visible {
  color: var(--brand-orange);
  border-bottom-color: var(--brand-orange);
}

.page-about .ab-shx__hint {
  margin: 20px 0 22px;
  font-size: 15px;
  line-height: 1.78;
  color: var(--muted-600);
}

/* ---------- 06 合作与认可 ---------- */
.page-about .ab-partners {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .ab-partner {
  position: relative;
  padding: 22px 18px 20px;
  background: var(--paper-050);
  border: 1px solid var(--ab-line);
  box-shadow: var(--shadow-card);
  transition: transform var(--t-fast) var(--ease), box-shadow var(--t-fast) var(--ease),
    border-color var(--t-fast) var(--ease);
}

.page-about .ab-partner:hover,
.page-about .ab-partner:focus-within {
  transform: translateY(-2px);
  border-color: var(--brand-orange);
  box-shadow: var(--shadow-card-hover);
}

.page-about .ab-partner::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 46px;
  height: 4px;
  background: var(--brand-orange);
}

.page-about .ab-partner__num {
  margin: 0 0 8px;
  font-size: 24px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--ink-900);
}

.page-about .ab-partner__title {
  margin: 0 0 8px;
  font-size: 16px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--ink-900);
}

.page-about .ab-partner__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--muted-600);
}

/* ---------- 结尾行动区 ---------- */
.page-about .ab-cta {
  position: relative;
  overflow: hidden;
  margin-top: 26px;
  padding: 32px 22px;
  background: var(--paper-100);
  border: 1px solid var(--ab-line);
  box-shadow: var(--shadow-card);
}

.page-about .ab-cta::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 120px;
  height: 6px;
  background: var(--brand-orange);
}

.page-about .ab-cta__index {
  margin: 0 0 10px;
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--brand-orange);
}

.page-about .ab-cta__title {
  margin: 0;
  max-width: 24em;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(21px, 4.4vw, 28px);
  line-height: 1.28;
  letter-spacing: -0.012em;
  color: var(--ink-900);
}

.page-about .ab-cta__text {
  margin: 14px 0 22px;
  max-width: 42em;
  font-size: 15px;
  line-height: 1.78;
  color: var(--muted-600);
}

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

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .ab-partners {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .ab-stats {
    gap: 26px 24px;
  }
}

@media (min-width: 760px) {
  .page-about .ab-hero__frame {
    padding: 56px 44px 64px;
  }

  .page-about .ab-lead {
    font-size: 17px;
  }

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

  .page-about .ab-stat {
    padding: 0 18px;
    border-left: 1px solid rgba(247, 243, 236, 0.16);
  }

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

  .page-about .ab-partner {
    padding: 24px 22px 22px;
  }
}

@media (min-width: 900px) {
  .page-about .ab-roles {
    grid-template-columns: minmax(0, 1fr) 330px;
    gap: 28px;
    align-items: start;
  }

  .page-about .ab-stds {
    grid-template-columns: minmax(0, 1fr) 340px;
    gap: 34px;
    align-items: start;
  }

  .page-about .ab-shx {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 38px;
    align-items: center;
  }

  .page-about .ab-roles__figure img {
    min-height: 240px;
    object-fit: cover;
  }
}

@media (min-width: 1024px) {
  .page-about .ab-body {
    grid-template-columns: var(--ab-rail-w) minmax(0, 1fr);
    gap: 56px;
    padding-top: 52px;
    padding-bottom: 84px;
  }

  .page-about .ab-rail {
    position: sticky;
    top: calc(var(--header-h) + 28px);
    margin: 0;
    padding: 0;
    overflow: visible;
    border-left: 1px solid var(--ab-line);
  }

  .page-about .rail__title {
    display: block;
    padding-left: 15px;
  }

  .page-about .rail__list {
    flex-direction: column;
    gap: 2px;
    padding: 0;
    white-space: normal;
  }

  .page-about .rail__link {
    padding: 10px 12px 10px 15px;
    border: 0;
    border-left: 3px solid transparent;
    margin-left: -1px;
    background: transparent;
    font-size: 14px;
  }

  .page-about .rail__link[aria-current="true"] {
    border-left-color: var(--brand-orange);
    background: var(--orange-200);
  }

  .page-about .ab-sec {
    padding: 44px 0;
  }

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

  .page-about .ab-tl__title {
    font-size: 20px;
  }

  .page-about .ab-cta {
    padding: 40px 36px;
  }
}

@media (min-width: 1200px) {
  .page-about .ab-roles {
    grid-template-columns: minmax(0, 1fr) 380px;
    gap: 34px;
  }

  .page-about .ab-stds {
    grid-template-columns: minmax(0, 1fr) 380px;
    gap: 44px;
  }
}

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

  .page-about .ab-role:hover,
  .page-about .ab-role:focus-within,
  .page-about .ab-partner:hover,
  .page-about .ab-partner:focus-within {
    transform: none;
  }
}
<<<END>>>