.page-about {
  --ab-hair: 1px solid var(--line);
  --ab-block: clamp(3rem, 7vw, 6.5rem);
  background: var(--ink);
  color: var(--text);
  overflow-x: clip;
}

.page-about .ab-crumb {
  padding-top: clamp(1.25rem, 4vw, 2.25rem);
}

.page-about .ab-crumb .breadcrumb__link {
  color: var(--muted);
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
}

.page-about .ab-hero__grid {
  display: grid;
  gap: clamp(2.25rem, 5vw, 4rem);
  padding: clamp(1.75rem, 5vw, 4rem) 0 clamp(2.5rem, 7vw, 5rem);
}

.page-about .ab-hero__eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  margin: 0 0 1.25rem;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .ab-hero__eyebrow::before {
  content: "";
  width: 34px;
  height: 1px;
  background: var(--signal);
}

.page-about .ab-hero__title {
  margin: 0;
  font-size: clamp(38px, 6.6vw, 92px);
  line-height: 0.98;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--text);
}

.page-about .ab-hero__title em {
  font-style: normal;
  color: var(--mint);
}

.page-about .ab-hero__text {
  margin: clamp(1.25rem, 3vw, 1.75rem) 0 0;
  max-width: 34ch;
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .ab-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: clamp(1.5rem, 3vw, 2.25rem);
}

.page-about .ab-hero__index {
  border-top: var(--ab-hair);
  padding-top: 1.1rem;
}

.page-about .ab-hero__index-label {
  margin: 0 0 0.9rem;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

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

.page-about .ab-hero__index-link {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  padding: 0.6rem 0;
  border-bottom: 1px solid rgba(34, 48, 90, 0.55);
  color: var(--text);
  text-decoration: none;
  font-size: 14px;
  line-height: 1.5;
  transition: color 0.2s var(--ease), padding-left 0.2s var(--ease);
}

.page-about .ab-hero__index-link .mono {
  flex: none;
  font-size: 12px;
  color: var(--muted);
  letter-spacing: 0.08em;
  transition: color 0.2s var(--ease);
}

.page-about .ab-hero__index-link:hover,
.page-about .ab-hero__index-link:focus-visible {
  color: var(--mint);
  padding-left: 0.4rem;
}

.page-about .ab-hero__index-link:hover .mono,
.page-about .ab-hero__index-link:focus-visible .mono {
  color: var(--signal);
}

/* ---------- 通用章节骨架 ---------- */
.page-about .ab-sec {
  padding: var(--ab-block) 0;
}

.page-about .ab-sec__head {
  margin-bottom: clamp(1.75rem, 4vw, 3rem);
}

.page-about .ab-sec__num {
  margin: 0 0 0.85rem;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--muted);
}

.page-about .ab-sec__title {
  margin: 0;
  max-width: 22ch;
  font-size: clamp(22px, 2.6vw, 34px);
  font-weight: 500;
  line-height: 1.3;
  letter-spacing: 0.01em;
  color: var(--text);
}

.page-about .ab-sec__note {
  margin: 1rem 0 0;
  max-width: 46ch;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 01 开场 ---------- */
.page-about .ab-open {
  display: grid;
  gap: clamp(1.75rem, 4vw, 2.75rem);
}

.page-about .ab-open__text {
  margin: 0;
  max-width: 52ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .ab-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: var(--ab-hair);
}

.page-about .ab-stat {
  background: var(--ink-2);
  padding: clamp(1rem, 2.4vw, 1.5rem);
}

.page-about .ab-stat__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(24px, 3.2vw, 34px);
  line-height: 1.1;
  letter-spacing: -0.01em;
  color: var(--mint);
}

.page-about .ab-stat__label {
  margin: 0.5rem 0 0;
  font-size: 14px;
  color: var(--text);
}

.page-about .ab-stat__sub {
  margin: 0.3rem 0 0;
  font-size: 12px;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 02 版本 ---------- */
.page-about .ab-vers {
  display: grid;
  gap: clamp(1.25rem, 3vw, 2rem);
}

.page-about .ab-ver {
  border-top: 1px solid var(--line);
  padding-top: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.7rem;
}

.page-about .ab-ver__tag {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--signal);
}

.page-about .ab-ver__name {
  margin: 0;
  font-size: clamp(18px, 2vw, 22px);
  font-weight: 500;
  line-height: 1.35;
  color: var(--text);
}

.page-about .ab-ver__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .ab-ver__meter {
  position: relative;
  height: 3px;
  margin-top: auto;
  background: rgba(42, 55, 96, 0.6);
  overflow: hidden;
}

.page-about .ab-ver__meter span {
  display: block;
  height: 100%;
  background: linear-gradient(90deg, var(--cyan-a), var(--cyan-b));
  transition: width 0.6s var(--ease);
}

.page-about .ab-ver--v1 .ab-ver__meter span { width: 34%; }
.page-about .ab-ver--v2 .ab-ver__meter span { width: 67%; }
.page-about .ab-ver--v3 .ab-ver__meter span { width: 100%; }

.page-about .ab-ver__meter-label {
  margin: 0;
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--muted);
}

/* ---------- 03 团队 ---------- */
.page-about .ab-team {
  display: grid;
  gap: clamp(2rem, 4vw, 3rem);
}

.page-about .ab-team__lead {
  margin: 1rem 0 0;
  max-width: 46ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .ab-roles {
  display: grid;
  gap: 1px;
  margin-top: clamp(1.5rem, 3vw, 2rem);
  background: var(--line);
  border: var(--ab-hair);
}

.page-about .ab-role {
  background: var(--ink-2);
  padding: clamp(1rem, 2.4vw, 1.5rem);
  transition: background 0.24s var(--ease);
}

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

.page-about .ab-role__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(22px, 2.6vw, 28px);
  line-height: 1.1;
  color: var(--mint);
}

.page-about .ab-role__name {
  margin: 0.5rem 0 0;
  font-size: 15.5px;
  font-weight: 500;
  color: var(--text);
}

.page-about .ab-role__desc {
  margin: 0.5rem 0 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .ab-role__with {
  margin: 0.9rem 0 0;
  padding-top: 0.7rem;
  border-top: 1px solid rgba(34, 48, 90, 0.7);
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: 0.02em;
  color: var(--idle);
  transition: color 0.24s var(--ease);
}

.page-about .ab-role:hover .ab-role__with,
.page-about .ab-role:focus-within .ab-role__with {
  color: var(--muted);
}

/* ---------- 图片框 ---------- */
.page-about .ab-figure {
  margin: 0;
  border: var(--ab-hair);
  background: var(--panel);
  overflow: hidden;
}

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

.page-about .ab-figure__cap {
  padding: 0.85rem 1rem 1rem;
  font-size: 12px;
  line-height: 1.7;
  color: var(--muted);
  border-top: 1px solid rgba(34, 48, 90, 0.6);
}

/* ---------- 04 广州 ---------- */
.page-about .ab-gz {
  display: grid;
  gap: clamp(1.75rem, 4vw, 3rem);
}

.page-about .ab-gz__lead {
  margin: 1rem 0 0;
  max-width: 46ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .ab-gz__list {
  list-style: none;
  margin: clamp(1.25rem, 3vw, 1.75rem) 0 0;
  padding: 0;
  display: grid;
  gap: 0.9rem;
}

.page-about .ab-gz__list li {
  position: relative;
  padding-left: 1.4rem;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--text);
}

.page-about .ab-gz__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.7em;
  width: 0.55rem;
  height: 1px;
  background: var(--signal);
}

.page-about .ab-gz__addr {
  margin: clamp(1.25rem, 3vw, 1.75rem) 0 0;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
  border-left: 2px solid var(--green-deep);
  padding-left: 0.9rem;
}

/* ---------- 05 内容标准 ---------- */
.page-about .ab-std {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: var(--ab-hair);
}

.page-about .ab-std__item {
  display: grid;
  gap: 0.6rem;
  padding: clamp(1.25rem, 3vw, 1.9rem) 0;
  border-bottom: var(--ab-hair);
}

.page-about .ab-std__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--signal);
}

.page-about .ab-std__title {
  margin: 0;
  font-size: clamp(16.5px, 1.8vw, 20px);
  font-weight: 500;
  line-height: 1.45;
  color: var(--text);
}

.page-about .ab-std__body p {
  margin: 0.6rem 0 0;
  max-width: 58ch;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 06 合作 ---------- */
.page-about .ab-partners {
  display: grid;
  gap: 1px;
  background: var(--line);
  border: var(--ab-hair);
}

.page-about .ab-partner {
  background: var(--ink);
  padding: clamp(1.25rem, 3vw, 2rem);
  transition: background 0.24s var(--ease);
}

.page-about .ab-partner:hover {
  background: var(--ink-2);
}

.page-about .ab-partner__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(28px, 4vw, 44px);
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--mint);
}

.page-about .ab-partner__name {
  margin: 0.75rem 0 0;
  font-size: 16px;
  font-weight: 500;
  color: var(--text);
}

.page-about .ab-partner__desc {
  margin: 0.5rem 0 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .ab-partners__cta {
  margin: clamp(1.5rem, 3vw, 2rem) 0 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .ab-partners__cta a {
  color: var(--mint);
  text-decoration: none;
  border-bottom: 1px solid var(--green-deep);
  transition: border-color 0.2s var(--ease);
}

.page-about .ab-partners__cta a:hover,
.page-about .ab-partners__cta a:focus-visible {
  border-color: var(--signal);
}

/* ---------- 07 里程碑 ---------- */
.page-about .ab-mile {
  position: relative;
  padding: var(--ab-block) 0;
  overflow: hidden;
  background: var(--ink-2);
}

.page-about .ab-mile__bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.22;
  pointer-events: none;
}

.page-about .ab-mile__inner {
  position: relative;
  z-index: 1;
}

.page-about .ab-mile__list {
  display: grid;
  gap: 0;
  border-top: var(--ab-hair);
}

.page-about .ab-mile__item {
  position: relative;
  border-bottom: var(--ab-hair);
}

.page-about .ab-mile__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 1.55rem;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--idle);
  transition: background 0.24s var(--ease);
}

.page-about .ab-mile__item[data-open="true"]::before,
.page-about .ab-mile__item:hover::before {
  background: var(--signal);
}

.page-about .ab-mile__head {
  display: grid;
  grid-template-columns: auto 1fr auto;
  grid-template-areas:
    "idx label mark"
    "idx name  mark";
  align-items: center;
  column-gap: 0.9rem;
  row-gap: 0.25rem;
  width: 100%;
  padding: 1.1rem 0 1.1rem 1.35rem;
  background: none;
  border: 0;
  text-align: left;
  cursor: pointer;
  color: var(--text);
  font: inherit;
}

.page-about .ab-mile__idx {
  grid-area: idx;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--muted);
  align-self: start;
  padding-top: 0.15rem;
}

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

.page-about .ab-mile__name {
  grid-area: name;
  font-size: 15.5px;
  font-weight: 500;
  line-height: 1.5;
  color: var(--text);
}

.page-about .ab-mile__head .fold__mark {
  grid-area: mark;
  flex: none;
}

.page-about .ab-mile__body {
  padding: 0 0 1.35rem 3.05rem;
}

.page-about .ab-mile__body p {
  margin: 0;
  max-width: 54ch;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 08 联系 ---------- */
.page-about .ab-talk {
  position: relative;
  padding-bottom: clamp(2.5rem, 6vw, 4.5rem);
}

.page-about .ab-talk__tag {
  margin: 0 0 1rem;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--orange);
}

.page-about .ab-talk__title {
  margin: 0;
  max-width: 24ch;
  font-size: clamp(24px, 3.4vw, 44px);
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: 0.01em;
  color: var(--text);
}

.page-about .ab-talk__text {
  margin: clamp(1rem, 3vw, 1.5rem) 0 0;
  max-width: 48ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .ab-talk__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: clamp(1.5rem, 3vw, 2rem);
}

.page-about .ab-talk__line {
  margin-top: clamp(2.5rem, 6vw, 4rem);
  height: 2px;
  background: linear-gradient(90deg, var(--cyan-a), var(--cyan-b) 55%, rgba(27, 91, 255, 0));
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .ab-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

  .page-about .ab-std__item {
    grid-template-columns: 4.5rem minmax(0, 1fr);
    align-items: start;
    gap: 1.25rem;
  }

  .page-about .ab-std__num {
    padding-top: 0.35rem;
  }

  .page-about .ab-std__body p {
    margin-top: 0.5rem;
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero__grid {
    grid-template-columns: minmax(0, 1.6fr) minmax(0, 0.85fr);
    align-items: end;
    column-gap: clamp(3rem, 6vw, 5.5rem);
  }

  .page-about .ab-hero__index {
    padding-bottom: 0.5rem;
  }

  .page-about .ab-open {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.35fr);
    align-items: start;
    column-gap: clamp(2rem, 5vw, 4rem);
  }

  .page-about .ab-vers {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    column-gap: clamp(1.5rem, 3vw, 2.5rem);
  }

  .page-about .ab-team {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    align-items: start;
    column-gap: clamp(2rem, 5vw, 3.5rem);
  }

  .page-about .ab-team__figure {
    position: sticky;
    top: 6rem;
  }

  .page-about .ab-gz {
    grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
    align-items: center;
    column-gap: clamp(2rem, 5vw, 4rem);
  }
}

@media (min-width: 1080px) {
  .page-about .ab-roles {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .ab-mile__head {
    grid-template-columns: 3.5rem 11rem minmax(0, 1fr) auto;
    grid-template-areas: "idx label name mark";
    column-gap: 1.25rem;
    padding-left: 1.6rem;
  }

  .page-about .ab-mile__body {
    padding-left: 17.6rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-ver__meter span,
  .page-about .ab-hero__index-link,
  .page-about .ab-role,
  .page-about .ab-role__with,
  .page-about .ab-partner,
  .page-about .ab-mile__item::before {
    transition: none;
  }

  .page-about .ab-hero__index-link:hover,
  .page-about .ab-hero__index-link:focus-visible {
    padding-left: 0;
  }
}