.page-about {
  --ab-gutter: 20px;
  overflow-x: hidden;
}

@media (min-width: 768px) {
  .page-about {
    --ab-gutter: 40px;
  }
}

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

/* 面包屑 */
.page-about .breadcrumb {
  padding: 16px var(--ab-gutter) 0;
}

.page-about .breadcrumb__current {
  font-size: 13px;
  color: var(--slate);
}

/* 首屏 */
.page-about .ab-hero {
  position: relative;
  overflow: hidden;
  padding: 30px var(--ab-gutter) 34px;
}

.page-about .ab-hero::before {
  content: "";
  position: absolute;
  right: -70px;
  bottom: -110px;
  width: 260px;
  height: 260px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(0, 224, 138, 0.18), transparent 68%);
  pointer-events: none;
}

.page-about .ab-hero__inner {
  position: relative;
  max-width: 1080px;
}

.page-about .ab-hero__title {
  margin: 16px 0 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(32px, 8.4vw, 58px);
  line-height: 1.1;
  letter-spacing: 0.06em;
  color: var(--white);
}

.page-about .ab-hero__lede {
  margin: 20px 0 0;
  max-width: 38em;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.82);
}

.page-about .ab-hero__facts {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: rgba(255, 255, 255, 0.66);
}

.page-about .ab-hero__facts .num {
  margin-right: 4px;
  font-size: 20px;
  color: var(--signal);
}

.page-about .ab-index {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 18px;
  margin-top: 30px;
  padding-top: 12px;
  border-top: 1px solid rgba(255, 255, 255, 0.16);
}

.page-about .ab-index a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--signal);
  text-decoration: none;
}

.page-about .ab-index a:hover,
.page-about .ab-index a:focus-visible {
  color: var(--referee);
}

/* 首屏下方横向画面 */
.page-about .ab-band {
  margin: 16px 0 0;
}

.page-about .ab-band .figure__img {
  display: block;
  width: 100%;
  height: auto;
  max-height: 360px;
  object-fit: cover;
}

.page-about .ab-band .figure__caption {
  padding: 10px var(--ab-gutter) 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--slate);
}

@media (min-width: 1024px) {
  .page-about .ab-band .figure__img {
    max-height: 460px;
  }
}

/* 章节通用 */
.page-about .ab-section {
  padding: 46px var(--ab-gutter) 50px;
}

.page-about .ab-h2 {
  margin: 12px 0 0;
  font-family: var(--font-head);
  font-size: clamp(24px, 5vw, 36px);
  font-weight: 800;
  line-height: 1.26;
  letter-spacing: 0.06em;
  color: var(--ink);
}

.page-about .panel--dark .ab-h2,
.page-about .panel--deep .ab-h2 {
  color: var(--white);
}

.page-about .ab-note {
  margin: 12px 0 0;
  max-width: 46em;
  font-size: 13px;
  line-height: 1.78;
  color: var(--slate);
}

.page-about .panel--dark .ab-note,
.page-about .panel--deep .ab-note {
  color: rgba(255, 255, 255, 0.62);
}

.page-about .panel--dark .prose,
.page-about .panel--deep .prose {
  color: rgba(255, 255, 255, 0.84);
}

/* 分栏 */
.page-about .ab-split {
  display: grid;
  gap: 20px;
}

.page-about .ab-split__main p {
  margin: 0 0 16px;
}

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

@media (min-width: 900px) {
  .page-about .ab-split {
    grid-template-columns: minmax(0, 4fr) minmax(0, 7fr);
    gap: 56px;
    align-items: start;
  }
}

/* 三阶段 */
.page-about .ab-stages {
  display: grid;
  gap: 16px;
  margin-top: 30px;
}

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

.page-about .ab-stage {
  padding: 22px 20px 24px;
  background: linear-gradient(158deg, rgba(0, 224, 138, 0.09), rgba(11, 31, 58, 0.92));
  border-top: 2px solid var(--signal);
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, 0 100%);
}

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

.page-about .ab-stage__title {
  margin: 10px 0 16px;
  font-family: var(--font-head);
  font-size: 22px;
  font-weight: 800;
  letter-spacing: 0.06em;
  color: var(--white);
}

.page-about .ab-stage dl {
  margin: 0;
  display: grid;
  gap: 12px;
}

.page-about .ab-stage dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--slate);
}

.page-about .ab-stage dd {
  margin: 4px 0 0;
  font-size: 14px;
  line-height: 1.72;
  color: rgba(255, 255, 255, 0.84);
}

.page-about .ab-stage-foot {
  display: grid;
  gap: 22px;
  margin-top: 30px;
  padding-top: 22px;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
}

.page-about .ab-stage-figure {
  margin: 0;
}

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

.page-about .ab-stage-figure .figure__caption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.55);
}

@media (min-width: 900px) {
  .page-about .ab-stage-foot {
    grid-template-columns: minmax(0, 1fr) 280px;
    gap: 48px;
    align-items: center;
  }
}

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

@media (min-width: 900px) {
  .page-about .ab-team {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: 48px;
    align-items: start;
  }
}

.page-about .ab-role {
  padding: 16px 0 18px;
  border-top: 1px solid rgba(255, 255, 255, 0.14);
}

.page-about .ab-role__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
}

.page-about .ab-role__count {
  font-family: var(--font-mono);
  font-size: 34px;
  line-height: 1;
  color: var(--white);
}

.page-about .ab-role__name {
  font-size: 16px;
  letter-spacing: 0.06em;
  color: var(--signal);
}

.page-about .ab-role--review .ab-role__name {
  color: var(--referee);
}

.page-about .ab-role__desc {
  margin: 10px 0 14px;
  max-width: 42em;
  font-size: 14px;
  line-height: 1.78;
  color: rgba(255, 255, 255, 0.78);
}

.page-about .ab-dots {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.page-about .ab-dot {
  display: block;
  width: 10px;
  height: 10px;
  border-radius: 2px;
  background: var(--signal);
  opacity: 0.85;
}

.page-about .ab-role--review .ab-dot {
  background: var(--referee);
}

.page-about .ab-role--support .ab-dot {
  background: rgba(255, 255, 255, 0.42);
}

.page-about .ab-team__aside {
  display: grid;
  gap: 16px;
}

.page-about .ab-team__aside .figure {
  margin: 0;
}

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

.page-about .ab-team__aside .figure__caption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.55);
}

.page-about .ab-team__aside-note {
  margin: 0;
  padding-left: 14px;
  border-left: 3px solid var(--signal);
  font-size: 13px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.68);
}

/* 口径刻度 */
.page-about .ab-version__body {
  display: grid;
  gap: 24px;
  margin-top: 30px;
}

.page-about .ab-rail {
  display: flex;
  gap: 10px;
  margin: 0;
  padding: 0 0 10px;
  list-style: none;
  overflow-x: auto;
  scroll-snap-type: x proximity;
}

.page-about .ab-rail__item {
  flex: 0 0 150px;
  padding: 8px 0 8px 12px;
  border-left: 3px solid rgba(255, 255, 255, 0.18);
  scroll-snap-align: start;
}

.page-about .ab-rail__v {
  display: block;
  font-family: var(--font-mono);
  font-size: 20px;
  letter-spacing: 0.04em;
  color: var(--white);
}

.page-about .ab-rail__d {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  line-height: 1.62;
  color: rgba(255, 255, 255, 0.6);
}

.page-about .ab-rail__link {
  display: block;
  min-height: 44px;
  color: inherit;
  text-decoration: none;
}

.page-about .ab-rail__link:hover .ab-rail__v,
.page-about .ab-rail__link:focus-visible .ab-rail__v {
  color: var(--referee);
}

.page-about .ab-version:has(#ver-v3:target) .ab-rail__item:nth-child(3),
.page-about .ab-version:has(#ver-v4:target) .ab-rail__item:nth-child(4),
.page-about .ab-version:has(#ver-v6:target) .ab-rail__item:nth-child(6) {
  border-left-color: var(--referee);
}

.page-about .ab-version:has(#ver-v3:target) a[href="#ver-v3"] .ab-rail__v,
.page-about .ab-version:has(#ver-v4:target) a[href="#ver-v4"] .ab-rail__v,
.page-about .ab-version:has(#ver-v6:target) a[href="#ver-v6"] .ab-rail__v {
  color: var(--referee);
}

@media (min-width: 900px) {
  .page-about .ab-version__body {
    grid-template-columns: 240px minmax(0, 1fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .ab-rail {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .ab-rail__item {
    flex: none;
  }
}

.page-about .ab-stage-panels {
  min-height: 210px;
}

.page-about .ab-vpanel {
  display: none;
  padding: 22px 20px 24px;
  background: rgba(255, 255, 255, 0.04);
  border-left: 2px solid var(--referee);
}

.page-about .ab-vpanel--default {
  display: block;
  border-left-color: rgba(255, 255, 255, 0.22);
}

.page-about .ab-vpanel:target {
  display: block;
}

.page-about .ab-stage-panels:has(.ab-vpanel:target) .ab-vpanel--default {
  display: none;
}

.page-about .ab-vpanel__tag {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--referee);
}

.page-about .ab-vpanel--default .ab-vpanel__tag {
  color: rgba(255, 255, 255, 0.6);
}

.page-about .ab-vpanel__lead {
  margin: 0 0 14px;
  font-size: 15px;
  line-height: 1.82;
  color: rgba(255, 255, 255, 0.86);
}

.page-about .ab-vpanel__list {
  margin: 0;
  padding-left: 18px;
  font-size: 14px;
  line-height: 1.82;
  color: rgba(255, 255, 255, 0.76);
}

/* 高原场景 */
.page-about .ab-plateau {
  display: grid;
  gap: 22px;
}

.page-about .ab-plateau__aside {
  padding-left: 16px;
  border-left: 3px solid var(--navy);
  font-size: 13px;
  line-height: 1.82;
  color: var(--slate);
}

.page-about .ab-plateau__aside p {
  margin: 0;
}

@media (min-width: 900px) {
  .page-about .ab-plateau {
    grid-template-columns: minmax(0, 6fr) minmax(0, 4fr);
    gap: 52px;
    align-items: start;
  }
}

/* 归档与边界 */
.page-about .ab-ledger {
  margin: 26px 0 0;
  padding: 0;
}

.page-about .ab-ledger__row {
  display: grid;
  gap: 6px;
  padding: 16px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.14);
}

@media (min-width: 760px) {
  .page-about .ab-ledger__row {
    grid-template-columns: 200px minmax(0, 1fr);
    gap: 24px;
  }
}

.page-about .ab-ledger dt {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--signal);
}

.page-about .ab-ledger dd {
  margin: 0;
  font-size: 14px;
  line-height: 1.82;
  color: rgba(255, 255, 255, 0.8);
}

.page-about .ab-boundary {
  display: grid;
  gap: 12px;
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-boundary li {
  position: relative;
  padding-left: 18px;
  font-size: 14px;
  line-height: 1.82;
  color: rgba(255, 255, 255, 0.78);
}

.page-about .ab-boundary li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.75em;
  width: 8px;
  height: 2px;
  background: var(--referee);
}

.page-about .ab-links {
  margin: 30px 0 0;
  padding-top: 18px;
  border-top: 1px solid rgba(255, 255, 255, 0.14);
  font-size: 14px;
  line-height: 1.9;
  color: rgba(255, 255, 255, 0.7);
}

.page-about .ab-links a {
  color: var(--signal);
  text-decoration: none;
  border-bottom: 1px solid rgba(0, 224, 138, 0.35);
}

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