.page-about {
  --ab-line: 1px solid var(--c-grid);
  background: var(--c-deep);
  color: var(--c-star);
  overflow-x: hidden;
}

/* ---------- 面包屑 ---------- */
.page-about .crumbs {
  padding-top: 20px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--c-grey);
}

.page-about .crumbs a {
  color: var(--c-cyan);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--t-fast) var(--ease);
}

.page-about .crumbs a:hover {
  border-bottom-color: var(--c-cyan);
}

.page-about .crumbs__sep {
  margin: 0 8px;
  color: var(--c-grid);
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
  padding: 34px 0 56px;
  border-bottom: var(--ab-line);
  overflow: hidden;
}

.page-about .ab-hero::before {
  content: "";
  position: absolute;
  top: -34%;
  right: -14%;
  width: 68%;
  height: 156%;
  background: linear-gradient(140deg, rgba(108, 75, 244, 0.34) 0%, rgba(0, 229, 255, 0.1) 48%, rgba(5, 10, 31, 0) 76%);
  transform: skewY(calc(var(--diag) * -1.4));
  pointer-events: none;
}

.page-about .ab-hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 32px;
}

.page-about .eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--c-cyan);
}

.page-about .ab-hero h1 {
  margin: 14px 0 0;
  font-size: clamp(28px, 5.4vw, 50px);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: 0.01em;
  color: var(--c-star);
}

.page-about .ab-hero .lead {
  margin: 18px 0 0;
  max-width: 52ch;
  font-size: 16.5px;
  line-height: 1.8;
  color: var(--c-grey);
}

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

.page-about .ab-hero__panel {
  position: relative;
  padding: 20px;
  border: var(--ab-line);
  background: linear-gradient(180deg, rgba(12, 19, 48, 0.92), rgba(5, 10, 31, 0.92));
}

.page-about .ab-hero__panel::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 72px;
  height: 2px;
  background: linear-gradient(90deg, var(--c-nebula), var(--c-cyan));
}

.page-about .ab-cap {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--c-grey);
}

.page-about .ab-facts {
  margin: 0;
  padding: 0;
  display: grid;
}

.page-about .ab-facts__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding: 11px 0;
  border-bottom: 1px solid rgba(27, 42, 94, 0.75);
}

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

.page-about .ab-facts dt {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--c-grey);
}

.page-about .ab-facts dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 700;
  color: var(--c-orange);
  text-shadow: 0 0 14px rgba(255, 122, 26, 0.35);
  text-align: right;
}

/* ---------- 主体骨架 ---------- */
.page-about .ab-body {
  display: grid;
  gap: 32px;
  padding: 52px 0 8px;
}

.page-about .index-rail {
  display: none;
}

.page-about .ab-sections {
  display: grid;
  gap: 44px;
  min-width: 0;
}

/* ---------- 章节 ---------- */
.page-about .ab-chapter {
  scroll-margin-top: 100px;
}

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

.page-about .ab-chapter__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(36px, 5.4vw, 54px);
  font-weight: 700;
  line-height: 0.9;
  letter-spacing: 0.02em;
  color: var(--c-nebula);
}

.page-about .ab-chapter__title {
  margin: 12px 0 0;
  font-size: clamp(18px, 2.2vw, 23px);
  font-weight: 700;
  letter-spacing: 0.07em;
  color: var(--c-star);
}

.page-about .ab-chapter__rule {
  display: block;
  width: 100%;
  height: 1px;
  margin-top: 18px;
  background: linear-gradient(90deg, var(--c-nebula) 0%, rgba(27, 42, 94, 0.15) 100%);
}

/* ---------- 双栏 ---------- */
.page-about .ab-cols {
  display: grid;
  gap: 26px;
}

.page-about .ab-prose p {
  margin: 0 0 16px;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.8;
  color: #c9d3f0;
}

.page-about .ab-prose p:last-child {
  margin-bottom: 0;
}

/* ---------- 图片 ---------- */
.page-about .ab-figure {
  margin: 0;
}

.page-about .ab-figure--flow {
  margin: 22px 0;
}

.page-about .ab-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border: var(--ab-line);
  background: var(--c-panel);
}

.page-about .ab-figure figcaption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.65;
  color: var(--c-grey);
}

.page-about .ab-banner {
  margin: 0 0 30px;
}

.page-about .ab-banner img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border: var(--ab-line);
  background: var(--c-panel);
}

/* ---------- 链接清单 ---------- */
.page-about .ab-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .ab-links li {
  display: grid;
  gap: 4px;
  padding-bottom: 12px;
  border-bottom: 1px solid rgba(27, 42, 94, 0.7);
}

.page-about .ab-links li:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}

.page-about .ab-links a {
  font-size: 15px;
  letter-spacing: 0.02em;
  color: var(--c-cyan);
  text-decoration: none;
  transition: color var(--t-fast) var(--ease);
}

.page-about .ab-links a:hover {
  color: var(--c-star);
  text-decoration: underline;
}

.page-about .ab-links span {
  font-size: 13px;
  line-height: 1.6;
  color: var(--c-grey);
}

/* ---------- 数据表 ---------- */
.page-about .ab-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-mono);
}

.page-about .ab-table th,
.page-about .ab-table td {
  padding: 11px 0;
  border-bottom: 1px solid rgba(27, 42, 94, 0.8);
  font-size: 13.5px;
  font-weight: 400;
  vertical-align: baseline;
}

.page-about .ab-table th {
  text-align: left;
  letter-spacing: 0.04em;
  color: var(--c-grey);
  transition: color var(--t-fast) var(--ease);
}

.page-about .ab-table td {
  text-align: right;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--c-cyan);
}

.page-about .ab-table tr:last-child th,
.page-about .ab-table tr:last-child td {
  border-bottom: 0;
}

.page-about .ab-table tr:hover th {
  color: var(--c-star);
}

/* ---------- 团队 ---------- */
.page-about .ab-team {
  display: grid;
  gap: 28px;
}

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

.page-about .ab-role {
  padding: 20px 18px;
  background: var(--c-deep);
  transition: background var(--t-base) var(--ease);
}

.page-about .ab-role:hover {
  background: var(--c-panel);
}

.page-about .ab-role__idx {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--c-nebula);
}

.page-about .ab-role__name {
  margin: 8px 0 10px;
  font-size: 16px;
  letter-spacing: 0.05em;
  color: var(--c-star);
}

.page-about .ab-role__desc {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--c-grey);
}

/* ---------- 校验步骤 ---------- */
.page-about .ab-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  border: var(--ab-line);
  background: var(--c-grid);
}

.page-about .ab-steps li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 13px 16px;
  background: var(--c-deep);
  font-size: 14px;
  line-height: 1.65;
  color: #c9d3f0;
}

.page-about .ab-steps__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--c-orange);
}

/* ---------- 时间轴 ---------- */
.page-about .ab-timeline {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .ab-tl {
  position: relative;
  padding: 0 0 26px 28px;
}

.page-about .ab-tl::before {
  content: "";
  position: absolute;
  top: 16px;
  bottom: 0;
  left: 4px;
  width: 1px;
  background: var(--c-grid);
}

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

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

.page-about .ab-tl__node {
  position: absolute;
  top: 6px;
  left: 0;
  width: 9px;
  height: 9px;
  background: var(--c-cyan);
  box-shadow: 0 0 0 3px rgba(0, 229, 255, 0.16);
  transition: background var(--t-base) var(--ease), box-shadow var(--t-base) var(--ease);
}

.page-about .ab-tl:hover .ab-tl__node {
  background: var(--c-orange);
  box-shadow: 0 0 0 4px rgba(255, 122, 26, 0.18);
}

.page-about .ab-tl__phase {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--c-nebula);
}

.page-about .ab-tl__title {
  margin: 6px 0 8px;
  font-size: 17px;
  letter-spacing: 0.04em;
  color: var(--c-star);
}

.page-about .ab-tl__text {
  margin: 0;
  max-width: 60ch;
  font-size: 15px;
  line-height: 1.78;
  color: var(--c-grey);
}

/* ---------- 备注 ---------- */
.page-about .ab-note {
  margin: 16px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--c-grey);
}

.page-about .ab-note a {
  color: var(--c-cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(0, 229, 255, 0.4);
}

.page-about .ab-note a:hover {
  border-bottom-color: var(--c-cyan);
}

/* ---------- 结尾 ---------- */
.page-about .ab-cta {
  display: grid;
  gap: 20px;
  margin: 64px 0 0;
  padding: 40px 0 8px;
  border-top: var(--ab-line);
}

.page-about .ab-cta h2 {
  margin: 0;
  font-size: clamp(20px, 3vw, 28px);
  letter-spacing: 0.06em;
  color: var(--c-star);
}

.page-about .ab-cta p {
  margin: 10px 0 0;
  max-width: 52ch;
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--c-grey);
}

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

/* ---------- 平板 ---------- */
@media (min-width: 760px) {
  .page-about .ab-cols {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 0;
  }

  .page-about .ab-cols > * {
    padding: 0 26px;
  }

  .page-about .ab-cols > *:first-child {
    padding-left: 0;
  }

  .page-about .ab-cols > * + * {
    padding-right: 0;
    border-left: var(--ab-line);
  }

  .page-about .ab-team {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: 32px;
    align-items: start;
  }

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

  .page-about .ab-banner img {
    max-height: 340px;
  }

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

  .page-about .ab-cta__actions {
    justify-content: flex-end;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-about .ab-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 48px;
    align-items: end;
  }

  .page-about .ab-chapter {
    display: grid;
    grid-template-columns: minmax(0, 3fr) minmax(0, 9fr);
    gap: 40px;
  }

  .page-about .ab-chapter__head {
    position: sticky;
    top: 104px;
    align-self: start;
  }
}

@media (min-width: 1080px) {
  .page-about .ab-body {
    grid-template-columns: 168px minmax(0, 1fr);
    gap: 56px;
  }

  .page-about .index-rail {
    display: block;
    position: sticky;
    top: 96px;
    align-self: start;
    padding-left: 14px;
    border-left: 1px solid var(--c-grid);
  }

  .page-about .index-rail__title {
    display: block;
    margin-bottom: 14px;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.2em;
    color: var(--c-grey);
  }

  .page-about .index-rail__item {
    display: block;
    padding: 7px 0;
    font-family: var(--font-mono);
    font-size: 12px;
    letter-spacing: 0.06em;
    color: var(--c-grey);
    text-decoration: none;
    transition: color var(--t-fast) var(--ease);
  }

  .page-about .index-rail__item:hover,
  .page-about .index-rail__item[aria-current] {
    color: var(--c-cyan);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-hero::before {
    transform: none;
  }
}