.page-about {
  --ab-rail-w: 168px;
  --ab-gold-wash: rgba(200, 164, 92, 0.12);
  --ab-gold-faint: rgba(200, 164, 92, 0.16);
  background: var(--vl-paper);
  color: var(--vl-char);
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  background: linear-gradient(180deg, var(--vl-white) 0%, var(--vl-paper) 100%);
  border-bottom: 1px solid var(--vl-line-soft);
  padding: clamp(24px, 4vw, 40px) 0 clamp(36px, 6vw, 68px);
}

.page-about .ab-hero__inner {
  display: grid;
  gap: clamp(28px, 5vw, 48px);
  align-items: center;
}

.page-about .ab-hero__text .vl-crumbs {
  margin-bottom: 18px;
}

.page-about .ab-hero__text .vl-eyebrow {
  margin-bottom: 14px;
}

.page-about .ab-hero__text .vl-h1 {
  margin: 0 0 20px;
  max-width: 18em;
}

.page-about .ab-hero__text .vl-lede {
  max-width: 36em;
}

.page-about .ab-hero__meta {
  list-style: none;
  margin: clamp(24px, 4vw, 34px) 0 0;
  padding: 18px 0 0;
  border-top: 1px solid var(--vl-line-gold);
  display: flex;
  flex-wrap: wrap;
  gap: 12px 30px;
}

.page-about .ab-hero__meta-item {
  display: flex;
  flex-direction: column;
  gap: 5px;
}

.page-about .ab-hero__meta-k {
  font-family: var(--vl-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--vl-mist);
  text-transform: uppercase;
}

.page-about .ab-hero__meta-v {
  font-family: var(--vl-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--vl-ink);
  font-variant-numeric: tabular-nums;
}

.page-about .ab-hero__media {
  position: relative;
  margin: 0;
  aspect-ratio: 16 / 10;
  overflow: hidden;
  border: 1px solid var(--vl-line-gold);
  background: linear-gradient(145deg, var(--vl-ink-2), var(--vl-ink));
}

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

.page-about .ab-hero__cap {
  position: absolute;
  left: 0;
  bottom: 0;
  padding: 8px 14px;
  font-family: var(--vl-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--vl-on-dark-strong);
  background: rgba(14, 42, 36, 0.72);
  border-top: 1px solid var(--vl-line-gold);
}

/* ---------- 章节头 ---------- */
.page-about .ab-sec-head {
  max-width: 48em;
  margin-bottom: clamp(24px, 4vw, 42px);
}

.page-about .ab-sec-head .vl-h2 {
  margin: 12px 0 16px;
}

.page-about .ab-sec-head .vl-lede {
  max-width: 40em;
}

.page-about .ab-sec-head--on-dark .vl-h2 {
  color: var(--vl-on-dark-strong);
}

.page-about .ab-sec-head--on-dark .vl-lede {
  color: var(--vl-on-dark);
}

/* ---------- 主张区 ---------- */
.page-about .ab-claim__body {
  display: grid;
  gap: clamp(26px, 4vw, 46px);
}

.page-about .ab-claim__prose {
  max-width: 36em;
}

.page-about .ab-claim__prose p {
  margin: 0 0 1.4em;
}

.page-about .ab-claim__list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--vl-line);
}

.page-about .ab-claim__item {
  padding: 20px 0 22px;
  border-bottom: 1px solid var(--vl-line-soft);
  display: grid;
  grid-template-columns: 44px 1fr;
  grid-template-areas:
    "idx title"
    "idx text";
  gap: 4px 12px;
}

.page-about .ab-claim__idx {
  grid-area: idx;
  font-family: var(--vl-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--vl-gold-deep);
  padding-top: 4px;
}

.page-about .ab-claim__item .vl-h3 {
  grid-area: title;
  margin: 0;
  font-size: 1.06rem;
}

.page-about .ab-claim__item p {
  grid-area: text;
  margin: 0;
  color: var(--vl-mist);
  font-size: 0.95rem;
  line-height: 1.75;
}

/* ---------- 版本沿革 ---------- */
.page-about .ab-arc {
  background: linear-gradient(180deg, var(--vl-paper), var(--vl-white));
}

.page-about .ab-ladder {
  display: block;
  width: 100%;
  height: auto;
  max-width: 640px;
  margin: 0 0 clamp(28px, 5vw, 48px);
  overflow: visible;
}

.page-about .ab-ladder__base {
  stroke: var(--vl-line);
  stroke-width: 1;
}

.page-about .ab-ladder__step {
  stroke: var(--vl-gold);
  stroke-width: 1;
}

.page-about .ab-ladder__step--1 { fill: rgba(92, 122, 128, 0.34); }
.page-about .ab-ladder__step--2 { fill: rgba(92, 122, 128, 0.52); }
.page-about .ab-ladder__step--3 { fill: rgba(200, 164, 92, 0.46); }
.page-about .ab-ladder__step--4 { fill: var(--vl-gold); }

.page-about .ab-ladder__label {
  font-family: var(--vl-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  fill: var(--vl-mist);
}

.page-about .ab-arc__layout {
  display: grid;
  gap: 24px;
}

.page-about .ab-arc__rail-cap {
  margin: 0 0 12px;
  font-family: var(--vl-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--vl-gold-deep);
  text-transform: uppercase;
}

.page-about .ab-arc__rail-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .ab-rail__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid var(--vl-line);
  background: var(--vl-white);
  text-decoration: none;
  color: var(--vl-mist);
  transition: border-color 180ms var(--vl-ease), color 180ms var(--vl-ease);
}

.page-about .ab-rail__link-index {
  font-family: var(--vl-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--vl-gold-deep);
}

.page-about .ab-rail__link-name {
  font-size: 0.9rem;
}

.page-about .ab-rail__link:hover,
.page-about .ab-rail__link:focus-visible {
  border-color: var(--vl-gold);
  color: var(--vl-ink);
}

.page-about .ab-rail__link.is-active,
.page-about .ab-rail__link[aria-current="true"] {
  border-color: var(--vl-gold);
  background: var(--ab-gold-wash);
  color: var(--vl-ink);
}

.page-about .ab-stage {
  position: relative;
  padding: clamp(24px, 4vw, 38px) 0;
  border-top: 1px solid var(--vl-line);
  overflow: hidden;
}

.page-about .ab-stage:first-child {
  border-top-color: var(--vl-gold);
}

.page-about .ab-stage__ghost {
  position: absolute;
  top: -8px;
  right: -6px;
  font-family: var(--vl-serif);
  font-weight: 900;
  font-size: clamp(3.6rem, 12vw, 7rem);
  line-height: 1;
  color: var(--ab-gold-faint);
  letter-spacing: 0.02em;
  pointer-events: none;
  user-select: none;
}

.page-about .ab-stage__ver {
  position: relative;
  margin: 0 0 8px;
  font-family: var(--vl-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--vl-gold-deep);
}

.page-about .ab-stage__name {
  position: relative;
  margin: 0 0 14px;
  font-family: var(--vl-serif);
  font-weight: 700;
  font-size: clamp(1.3rem, 3.2vw, 1.75rem);
  line-height: 1.35;
  color: var(--vl-ink);
  max-width: 16em;
}

.page-about .ab-stage__text {
  position: relative;
  margin: 0;
  max-width: 34em;
  line-height: 1.85;
  color: var(--vl-mist);
}

.page-about .ab-arc__figure {
  margin: clamp(26px, 4vw, 40px) 0 0;
  max-width: 380px;
}

.page-about .ab-arc__figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  aspect-ratio: 4 / 5;
  object-fit: cover;
  border: 1px solid var(--vl-line-gold);
  background: linear-gradient(160deg, var(--vl-ink-2), var(--vl-ink));
}

.page-about .ab-arc__cap {
  margin-top: 10px;
  font-family: var(--vl-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--vl-mist);
}

.page-about .ab-arc__note {
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 16px 0 0 18px;
  border-top: 1px solid var(--vl-line-soft);
  border-left: 2px solid var(--vl-gold);
  max-width: 34em;
  font-size: 0.94rem;
  line-height: 1.8;
  color: var(--vl-mist);
}

/* ---------- 覆盖规模 ---------- */
.page-about .ab-scale__wrap {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
}

.page-about .ab-scale {
  margin: 0;
  border-top: 1px solid var(--vl-line);
}

.page-about .ab-scale__row {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 6px 24px;
  padding: 18px 0;
  border-bottom: 1px solid var(--vl-line-soft);
}

.page-about .ab-scale__label {
  order: 2;
  flex: 1 1 220px;
  font-size: 0.92rem;
  color: var(--vl-mist);
  line-height: 1.6;
}

.page-about .ab-scale__val {
  order: 1;
  margin: 0;
  display: flex;
  align-items: baseline;
  gap: 6px;
  min-width: 9em;
}

.page-about .ab-scale__num {
  font-family: var(--vl-mono);
  font-size: clamp(1.5rem, 4.4vw, 2.15rem);
  font-weight: 500;
  letter-spacing: 0.01em;
  color: var(--vl-ink);
  font-variant-numeric: tabular-nums;
  line-height: 1.15;
}

.page-about .ab-scale__unit {
  font-family: var(--vl-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--vl-mist);
}

.page-about .ab-dots-block {
  background: var(--vl-white);
  border: 1px solid var(--vl-line);
  padding: clamp(18px, 3vw, 28px);
}

.page-about .ab-dots__cap {
  margin: 0 0 16px;
  font-family: var(--vl-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--vl-gold-deep);
}

.page-about .ab-dots {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
  margin-bottom: 18px;
}

.page-about .ab-dots span {
  display: block;
  width: 16px;
  height: 16px;
  border: 1px solid var(--vl-gold);
  background: var(--ab-gold-wash);
}

.page-about .ab-dots span:nth-child(5n) {
  background: var(--vl-gold);
}

.page-about .ab-dots span:nth-child(7n) {
  background: var(--vl-stone);
  border-color: var(--vl-stone);
}

.page-about .ab-dots__note {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--vl-mist);
}

/* ---------- 团队 ---------- */
.page-about .ab-team-sec {
  background: linear-gradient(180deg, var(--vl-white), var(--vl-paper));
}

.page-about .ab-team {
  border-top: 1px solid var(--vl-line);
}

.page-about .ab-team__row {
  display: grid;
  gap: 8px;
  padding: 22px 0;
  border-bottom: 1px solid var(--vl-line-soft);
}

.page-about .ab-team__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
}

.page-about .ab-team__name {
  margin: 0;
  font-family: var(--vl-serif);
  font-weight: 700;
  font-size: 1.14rem;
  color: var(--vl-ink);
}

.page-about .ab-team__num {
  margin: 0;
  font-family: var(--vl-mono);
  font-size: 1.05rem;
  letter-spacing: 0.04em;
  color: var(--vl-gold-deep);
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.page-about .ab-team__desc {
  margin: 0;
  max-width: 46em;
  font-size: 0.95rem;
  line-height: 1.8;
  color: var(--vl-mist);
}

.page-about .ab-team__support {
  margin-top: 24px;
  padding: 16px 20px;
  background: var(--vl-ink);
  border-left: 3px solid var(--vl-gold);
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 18px;
}

.page-about .ab-team__support-k {
  margin: 0;
  font-family: var(--vl-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--vl-gold-bright);
}

.page-about .ab-team__support-v {
  margin: 0;
  font-size: 0.95rem;
  color: var(--vl-on-dark-strong);
}

.page-about .ab-team__figure {
  margin: clamp(26px, 4vw, 40px) 0 0;
}

.page-about .ab-team__figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  aspect-ratio: 14 / 9;
  object-fit: cover;
  border: 1px solid var(--vl-line-gold);
  background: linear-gradient(160deg, var(--vl-ink-2), var(--vl-ink));
}

.page-about .ab-team__cap {
  margin-top: 10px;
  font-family: var(--vl-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--vl-mist);
}

/* ---------- 服务商 ---------- */
.page-about .ab-filter {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 22px;
}

.page-about .ab-filter__btn {
  appearance: none;
  font-family: var(--vl-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  padding: 9px 15px;
  border: 1px solid var(--vl-line);
  background: var(--vl-white);
  color: var(--vl-mist);
  cursor: pointer;
  transition: border-color 180ms var(--vl-ease), color 180ms var(--vl-ease), background-color 180ms var(--vl-ease);
}

.page-about .ab-filter__btn:hover {
  border-color: var(--vl-gold);
  color: var(--vl-ink);
}

.page-about .ab-filter__btn:focus-visible {
  outline: 2px solid var(--vl-gold-bright);
  outline-offset: 2px;
}

.page-about .ab-filter__btn[aria-pressed="true"] {
  border-color: var(--vl-gold);
  background: var(--ab-gold-wash);
  color: var(--vl-ink);
}

.page-about .ab-partner-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
  border-top: 1px solid var(--vl-line);
}

.page-about .ab-partner {
  padding: 20px 0 22px;
  border-bottom: 1px solid var(--vl-line-soft);
  display: grid;
  gap: 7px;
}

.page-about .ab-partner[hidden] {
  display: none !important;
}

.page-about .ab-partner__area {
  font-family: var(--vl-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--vl-gold-deep);
}

.page-about .ab-partner__title {
  margin: 0;
  font-family: var(--vl-serif);
  font-weight: 700;
  font-size: 1.04rem;
  color: var(--vl-ink);
}

.page-about .ab-partner__desc {
  margin: 0;
  max-width: 44em;
  font-size: 0.94rem;
  line-height: 1.8;
  color: var(--vl-mist);
}

.page-about .ab-partner__foot {
  margin: clamp(24px, 4vw, 34px) 0 0;
  padding: 18px 0 0;
  border-top: 1px solid var(--vl-line-gold);
  max-width: 46em;
  font-size: 0.95rem;
  line-height: 1.85;
  color: var(--vl-mist);
}

/* ---------- 备案与维护 ---------- */
.page-about .ab-record-sec {
  background: var(--vl-ink);
  color: var(--vl-on-dark);
}

.page-about .ab-record {
  display: grid;
  gap: clamp(26px, 4vw, 44px);
}

.page-about .ab-record__col {
  background: rgba(20, 58, 49, 0.55);
  border: 1px solid var(--vl-line-gold);
  padding: clamp(18px, 3vw, 28px);
}

.page-about .ab-record__title {
  margin: 0 0 16px;
  font-family: var(--vl-serif);
  font-weight: 700;
  font-size: 1.08rem;
  color: var(--vl-gold-bright);
}

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

.page-about .ab-record__item {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 4px 18px;
  padding: 11px 0;
  border-bottom: 1px solid rgba(200, 164, 92, 0.2);
}

.page-about .ab-record__item:last-child {
  border-bottom: none;
}

.page-about .ab-record__key {
  font-family: var(--vl-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--vl-gold);
}

.page-about .ab-record__val {
  margin: 0;
  font-family: var(--vl-mono);
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--vl-on-dark-strong);
  word-break: break-word;
  font-variant-numeric: tabular-nums;
}

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

.page-about .ab-record__cycle-item {
  display: grid;
  gap: 5px;
  padding: 12px 0;
  border-bottom: 1px solid rgba(200, 164, 92, 0.2);
}

.page-about .ab-record__cycle-item:last-child {
  border-bottom: none;
}

.page-about .ab-record__cycle-k {
  font-family: var(--vl-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--vl-gold);
}

.page-about .ab-record__cycle-v {
  font-size: 0.94rem;
  line-height: 1.75;
  color: var(--vl-on-dark-strong);
}

/* ---------- 下一步 ---------- */
.page-about .ab-next__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
  border-top: 1px solid var(--vl-line);
}

.page-about .ab-next__list li {
  border-bottom: 1px solid var(--vl-line-soft);
}

.page-about .ab-next__link {
  display: grid;
  gap: 5px;
  padding: 18px 0 20px;
  text-decoration: none;
  color: inherit;
  transition: background-color 180ms var(--vl-ease), padding-left 180ms var(--vl-ease);
}

.page-about .ab-next__link:hover,
.page-about .ab-next__link:focus-visible {
  background: var(--ab-gold-wash);
  padding-left: 12px;
}

.page-about .ab-next__link:focus-visible {
  outline: 2px solid var(--vl-gold-bright);
  outline-offset: 2px;
}

.page-about .ab-next__k {
  font-family: var(--vl-serif);
  font-weight: 700;
  font-size: 1.08rem;
  color: var(--vl-ink);
}

.page-about .ab-next__v {
  font-size: 0.92rem;
  line-height: 1.7;
  color: var(--vl-mist);
}

/* ---------- 响应式 ---------- */
@media (min-width: 768px) {
  .page-about .ab-claim__body {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: start;
    gap: clamp(32px, 5vw, 64px);
  }

  .page-about .ab-scale__wrap {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .ab-scale__row {
    flex-wrap: nowrap;
  }

  .page-about .ab-scale__val {
    order: 2;
    justify-content: flex-end;
    text-align: right;
  }

  .page-about .ab-scale__label {
    order: 1;
    flex: 1 1 auto;
  }

  .page-about .ab-team__row {
    grid-template-columns: minmax(180px, 20%) minmax(0, 1fr);
    align-items: baseline;
    gap: 8px 28px;
  }

  .page-about .ab-team__head {
    flex-direction: column;
    justify-content: flex-start;
    gap: 6px;
  }

  .page-about .ab-partner-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: clamp(24px, 4vw, 48px);
  }

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

  .page-about .ab-next__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: clamp(24px, 4vw, 48px);
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero__inner {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: center;
    gap: clamp(32px, 5vw, 64px);
  }

  .page-about .ab-hero__media {
    aspect-ratio: 4 / 3;
    margin-top: 28px;
  }

  .page-about .ab-claim__item {
    grid-template-columns: 54px 1fr;
  }
}

@media (min-width: 1024px) {
  .page-about .ab-arc__layout {
    grid-template-columns: var(--ab-rail-w) minmax(0, 1fr);
    gap: clamp(32px, 5vw, 72px);
  }

  .page-about .ab-arc__rail {
    position: sticky;
    top: calc(var(--vl-header-h) + 24px);
    align-self: start;
  }

  .page-about .ab-arc__rail-list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 0;
  }

  .page-about .ab-arc__rail-list li {
    border-top: 1px solid var(--vl-line-soft);
  }

  .page-about .ab-arc__rail-list li:last-child {
    border-bottom: 1px solid var(--vl-line-soft);
  }

  .page-about .ab-rail__link {
    width: 100%;
    border: none;
    background: transparent;
    padding: 12px 0 12px 14px;
    border-left: 2px solid transparent;
  }

  .page-about .ab-rail__link:hover,
  .page-about .ab-rail__link:focus-visible {
    border-left-color: var(--vl-gold);
    background: var(--ab-gold-wash);
  }

  .page-about .ab-rail__link.is-active,
  .page-about .ab-rail__link[aria-current="true"] {
    border-left-color: var(--vl-gold);
    background: transparent;
  }

  .page-about .ab-rail__link.is-active .ab-rail__link-name,
  .page-about .ab-rail__link[aria-current="true"] .ab-rail__link-name {
    color: var(--vl-ink);
    font-weight: 500;
  }

  .page-about .ab-arc__figure {
    max-width: 440px;
  }
}

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