.page-about {
  --about-rail-w: 88px;
  --about-ink-soft: rgba(10, 26, 42, 0.66);
  --about-pad: clamp(56px, 8vw, 112px);
  background: var(--abyss-900);
  color: var(--text);
  font-family: var(--font-sans);
  overflow-x: clip;
}

.page-about img {
  display: block;
  max-width: 100%;
  height: auto;
}

.page-about .about-shell {
  display: grid;
  grid-template-columns: 1fr;
}

.page-about .about-body {
  min-width: 0;
}

/* ---------- 左侧章节轴 ---------- */
.page-about .about-rail {
  display: none;
}

@media (min-width: 1080px) {
  .page-about .about-shell {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
  }

  .page-about .about-rail {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    position: sticky;
    top: 104px;
    align-self: start;
    padding: 44px 0;
    border-right: 1px solid var(--line);
    background: var(--abyss-900);
  }
}

.page-about .about-rail__cap {
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.24em;
  color: var(--rock-400);
  writing-mode: vertical-rl;
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 22px;
}

.page-about .about-rail__link {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 4px 6px;
  border-radius: var(--radius-sm);
  text-decoration: none;
  color: var(--rock-400);
  transition: color 200ms var(--ease);
}

.page-about .about-rail__num {
  font-size: var(--fs-xs);
  letter-spacing: 0.04em;
}

.page-about .about-rail__label {
  writing-mode: vertical-rl;
  font-size: 12px;
  letter-spacing: 0.24em;
  line-height: 1;
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--cyan-400);
}

/* ---------- 通用区块 ---------- */
.page-about .about-sec {
  padding-block: var(--about-pad);
}

.page-about .about-sec--abyss {
  background: var(--abyss-900);
  color: var(--text);
}

.page-about .about-sec--paper {
  background: var(--paper-100);
  color: var(--abyss-900);
  --text: var(--abyss-900);
  --text-dim: var(--about-ink-soft);
}

.page-about .about-kicker {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  font-size: var(--fs-xs);
  letter-spacing: 0.16em;
  color: var(--cyan-400);
  text-transform: uppercase;
}

.page-about .about-kicker::before {
  content: "";
  width: 22px;
  height: 1px;
  background: currentColor;
}

.page-about .about-sec--paper .about-kicker {
  color: var(--moss-600);
}

.page-about .about-head {
  display: grid;
  gap: 14px;
  max-width: 64ch;
}

.page-about .about-head__title {
  margin: 0;
  font-size: clamp(26px, 3.8vw, 44px);
  line-height: 1.16;
  font-weight: 800;
  letter-spacing: -0.015em;
}

.page-about .about-head__intro {
  margin: 0;
  font-size: var(--fs-base);
  line-height: 1.75;
  color: var(--text-dim);
}

.page-about .about-cap {
  margin: 12px 0 0;
  font-size: var(--fs-xs);
  letter-spacing: 0.06em;
  line-height: 1.7;
  color: var(--text-dim);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-block: clamp(32px, 5vw, 60px) clamp(56px, 8vw, 104px);
  background:
    radial-gradient(120% 90% at 90% -10%, rgba(63, 224, 206, 0.14), transparent 62%),
    var(--abyss-900);
  border-bottom: 1px solid var(--line);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(32px, 5vw, 64px);
  margin-top: clamp(28px, 4vw, 52px);
}

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

.page-about .about-hero__title {
  margin: 18px 0 0;
  font-size: clamp(34px, 6.2vw, 68px);
  line-height: 1.06;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.page-about .about-hero__lede {
  margin: 22px 0 0;
  max-width: 56ch;
  font-size: var(--fs-base);
  line-height: 1.8;
  color: var(--text-dim);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.page-about .about-stats {
  margin: 0;
  border-top: 1px solid var(--line-strong);
}

.page-about .about-stats__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-stats__row dt {
  font-size: var(--fs-xs);
  letter-spacing: 0.14em;
  color: var(--rock-400);
}

.page-about .about-stats__row dd {
  margin: 0;
  display: flex;
  align-items: baseline;
  gap: 6px;
  color: var(--cyan-400);
}

.page-about .about-stats__num {
  font-size: clamp(26px, 3.6vw, 40px);
  font-weight: 600;
  line-height: 1;
  letter-spacing: 0.01em;
}

.page-about .about-stats__unit {
  font-size: var(--fs-sm);
  color: var(--rock-400);
}

/* ---------- 分工 ---------- */
.page-about .about-who {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
  margin-top: clamp(32px, 5vw, 56px);
}

@media (min-width: 960px) {
  .page-about .about-who {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: start;
  }
}

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

.page-about .role {
  position: relative;
  padding: 20px 22px 20px 30px;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.6);
  border: 1px solid rgba(10, 26, 42, 0.1);
  outline: none;
  transition: background 200ms var(--ease), border-color 200ms var(--ease), box-shadow 200ms var(--ease);
}

.page-about .role:hover,
.page-about .role:focus,
.page-about .role:focus-within {
  background: #fff;
  border-color: rgba(90, 122, 95, 0.45);
  box-shadow: 0 18px 38px -30px rgba(10, 26, 42, 0.9);
}

.page-about .role__bar {
  position: absolute;
  left: 0;
  top: 16px;
  bottom: 16px;
  width: 5px;
  border-radius: var(--radius-pill);
}

.page-about .role__bar--moss { background: var(--moss-600); }
.page-about .role__bar--clay { background: var(--clay-500); }
.page-about .role__bar--abyss { background: var(--ink-600); }

.page-about .role__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
}

.page-about .role__name {
  margin: 0;
  font-size: var(--fs-md);
  font-weight: 700;
  letter-spacing: -0.01em;
}

.page-about .role__num {
  font-size: var(--fs-xs);
  letter-spacing: 0.08em;
  color: var(--clay-500);
  flex: none;
}

.page-about .role__duty {
  margin: 10px 0 0;
  font-size: var(--fs-sm);
  line-height: 1.75;
  color: var(--about-ink-soft);
}

.page-about .role__ask {
  margin: 12px 0 0;
  font-size: var(--fs-sm);
  line-height: 1.75;
  color: var(--abyss-700);
}

.page-about .role__tag {
  display: inline-block;
  margin-right: 8px;
  padding: 2px 9px;
  border-radius: var(--radius-pill);
  background: rgba(90, 122, 95, 0.16);
  color: var(--moss-600);
  font-size: 11px;
  letter-spacing: 0.08em;
  vertical-align: 1px;
}

.page-about .role__deliver {
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  margin-top: 0;
  transition: max-height 260ms var(--ease), opacity 200ms var(--ease), margin-top 260ms var(--ease);
}

.page-about .role:hover .role__deliver,
.page-about .role:focus .role__deliver,
.page-about .role:focus-within .role__deliver {
  max-height: 160px;
  opacity: 1;
  margin-top: 12px;
}

.page-about .role__deliver-label {
  margin: 0 0 4px;
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--rock-400);
}

.page-about .role__deliver p:last-child {
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.7;
  color: var(--abyss-900);
}

@media (max-width: 767px), (hover: none) {
  .page-about .role__deliver {
    max-height: none;
    opacity: 1;
    margin-top: 12px;
  }
}

.page-about .about-who__fig {
  margin: 0;
}

.page-about .about-who__img {
  width: 100%;
  aspect-ratio: 10 / 7;
  object-fit: cover;
  border-radius: var(--radius-lg);
  border: 1px solid rgba(10, 26, 42, 0.14);
}

/* ---------- 时间线 ---------- */
.page-about .about-tl__visual {
  margin: clamp(30px, 5vw, 48px) 0 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--line);
}

.page-about .about-tl__visual img {
  width: 100%;
  aspect-ratio: 14 / 6;
  object-fit: cover;
}

.page-about .about-tl {
  list-style: none;
  margin: clamp(32px, 5vw, 56px) 0 0;
  padding: 0 0 0 clamp(24px, 3.4vw, 42px);
  border-left: 1px solid var(--line-strong);
  display: grid;
  gap: clamp(26px, 3.6vw, 44px);
}

.page-about .about-tl__item {
  position: relative;
  display: grid;
  gap: 8px;
  max-width: 68ch;
}

.page-about .about-tl__item::before {
  content: "";
  position: absolute;
  left: calc(-1 * clamp(24px, 3.4vw, 42px) - 5px);
  top: 5px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--clay-500);
}

.page-about .about-tl__item--now::before {
  background: var(--cyan-400);
  animation: about-pulse 3.2s ease-in-out infinite;
}

@keyframes about-pulse {
  0%, 100% { box-shadow: 0 0 0 3px rgba(63, 224, 206, 0.18); }
  50% { box-shadow: 0 0 0 8px rgba(63, 224, 206, 0.04); }
}

.page-about .about-tl__when {
  margin: 0;
  font-size: var(--fs-xs);
  letter-spacing: 0.14em;
  color: var(--amber-500);
}

.page-about .about-tl__what {
  margin: 0;
  font-size: var(--fs-md);
  font-weight: 700;
  line-height: 1.4;
  letter-spacing: -0.01em;
  color: var(--mist-100);
}

.page-about .about-tl__why {
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.85;
  color: var(--text-dim);
}

/* ---------- 引文带 ---------- */
.page-about .about-quote {
  padding-block: clamp(48px, 7vw, 92px);
  background: var(--abyss-700);
  border-block: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-quote--amber {
  background: var(--abyss-900);
}

.page-about .about-quote__text {
  margin: 0;
  font-size: clamp(28px, 5.4vw, 60px);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--mist-100);
  max-width: 24ch;
}

.page-about .about-quote__mark {
  color: var(--cyan-400);
}

.page-about .about-quote--amber .about-quote__mark {
  color: var(--amber-500);
}

/* ---------- 节奏 ---------- */
.page-about .about-loop {
  list-style: none;
  margin: clamp(32px, 5vw, 52px) 0 0;
  padding: 0;
  border-top: 1px solid rgba(10, 26, 42, 0.16);
}

.page-about .about-loop__item {
  display: grid;
  gap: 6px;
  padding: 22px 0;
  border-bottom: 1px solid rgba(10, 26, 42, 0.16);
}

@media (min-width: 800px) {
  .page-about .about-loop__item {
    grid-template-columns: 92px minmax(0, 180px) minmax(0, 1fr);
    gap: 24px;
    align-items: start;
  }
}

.page-about .about-loop__no {
  margin: 0;
  font-size: var(--fs-xs);
  letter-spacing: 0.14em;
  color: var(--clay-500);
}

.page-about .about-loop__name {
  margin: 0;
  font-size: var(--fs-md);
  font-weight: 700;
  letter-spacing: -0.01em;
}

.page-about .about-loop__text {
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.8;
  color: var(--about-ink-soft);
  max-width: 66ch;
}

.page-about .about-loop__note {
  margin: clamp(24px, 3.4vw, 36px) 0 0;
  padding: 18px 22px;
  border-radius: var(--radius-md);
  border-left: 4px solid var(--moss-600);
  background: rgba(90, 122, 95, 0.1);
  font-size: var(--fs-sm);
  line-height: 1.8;
  color: var(--abyss-900);
  max-width: 78ch;
}

/* ---------- 行业分布 ---------- */
.page-about .about-dots {
  display: grid;
  gap: clamp(14px, 2vw, 22px);
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  margin-top: clamp(32px, 5vw, 52px);
}

.page-about .dot-cluster {
  padding: 18px 16px;
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
  background: rgba(27, 64, 92, 0.34);
  display: grid;
  gap: 10px;
  outline: none;
  transition: border-color 200ms var(--ease), background 200ms var(--ease);
}

.page-about .dot-cluster:hover,
.page-about .dot-cluster:focus {
  border-color: var(--line-strong);
  background: rgba(27, 64, 92, 0.6);
}

.page-about .dot-cluster__grid {
  display: flex;
  gap: 6px;
}

.page-about .dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--rock-400);
  opacity: 0.7;
  transition: background 200ms var(--ease), opacity 200ms var(--ease), transform 200ms var(--ease);
}

.page-about .dot-cluster:hover .dot,
.page-about .dot-cluster:focus .dot {
  background: var(--cyan-400);
  opacity: 1;
}

.page-about .dot-cluster:hover .dot:nth-child(2),
.page-about .dot-cluster:focus .dot:nth-child(2) {
  transform: translateY(-3px);
}

.page-about .dot-cluster__name {
  margin: 0;
  font-size: var(--fs-base);
  font-weight: 700;
}

.page-about .dot-cluster__pain {
  margin: 0;
  font-size: var(--fs-xs);
  line-height: 1.7;
  color: var(--text-dim);
}

.page-about .about-cases {
  margin-top: clamp(34px, 5vw, 60px);
  padding-left: clamp(18px, 3vw, 30px);
  border-left: 2px solid var(--line-strong);
  display: grid;
}

.page-about .about-cases__item {
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
  max-width: 72ch;
}

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

.page-about .about-cases__name {
  margin: 0 0 8px;
  font-size: var(--fs-base);
  font-weight: 700;
  color: var(--cyan-400);
}

.page-about .about-cases__item p {
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.85;
  color: var(--text-dim);
}

/* ---------- 共建 ---------- */
.page-about .about-build__visual {
  margin: clamp(30px, 4.5vw, 48px) 0 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid rgba(10, 26, 42, 0.14);
}

.page-about .about-build__visual img {
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .about-build {
  list-style: none;
  margin: clamp(28px, 4vw, 44px) 0 0;
  padding: 0;
}

.page-about .about-build__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 18px;
  padding: 24px 0;
  border-top: 1px solid rgba(10, 26, 42, 0.16);
}

.page-about .about-build__item:last-child {
  border-bottom: 1px solid rgba(10, 26, 42, 0.16);
}

.page-about .about-build__no {
  font-size: clamp(24px, 3.6vw, 40px);
  font-weight: 700;
  line-height: 1;
  color: var(--clay-500);
}

.page-about .about-build__body h3 {
  margin: 0 0 8px;
  font-size: var(--fs-md);
  font-weight: 700;
  letter-spacing: -0.01em;
}

.page-about .about-build__body p {
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.8;
  color: var(--about-ink-soft);
  max-width: 66ch;
}

.page-about .about-build__foot {
  margin-top: clamp(26px, 4vw, 40px);
  display: grid;
  gap: 18px;
  justify-items: start;
}

.page-about .about-build__note {
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.8;
  color: var(--abyss-900);
  max-width: 62ch;
}

/* ---------- 原则 ---------- */
.page-about .about-rules {
  list-style: none;
  margin: clamp(32px, 5vw, 52px) 0 0;
  padding: 0;
  display: grid;
  gap: clamp(14px, 2vw, 20px);
}

@media (min-width: 900px) {
  .page-about .about-rules {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-rules__item:last-child {
    grid-column: 1 / -1;
  }
}

.page-about .about-rules__item {
  padding: 22px 24px;
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
  background: linear-gradient(155deg, rgba(27, 64, 92, 0.62), rgba(10, 26, 42, 0.42));
  display: grid;
  gap: 8px;
  align-content: start;
}

.page-about .about-rules__code {
  margin: 0;
  font-size: var(--fs-xs);
  letter-spacing: 0.16em;
  color: var(--cyan-400);
}

.page-about .about-rules__item h3 {
  margin: 0;
  font-size: var(--fs-md);
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--mist-100);
}

.page-about .about-rules__item p {
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.8;
  color: var(--text-dim);
}

.page-about .about-rules__item a {
  color: var(--cyan-400);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .about-rules__item a:hover {
  color: var(--amber-500);
}

/* ---------- 收束 ---------- */
.page-about .about-cta {
  padding-block: clamp(52px, 8vw, 104px);
  background:
    radial-gradient(90% 130% at 8% 0%, rgba(63, 224, 206, 0.13), transparent 62%),
    var(--abyss-700);
  border-top: 1px solid var(--line-strong);
}

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

@media (min-width: 900px) {
  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: end;
  }
}

.page-about .about-cta__title {
  margin: 16px 0 0;
  font-size: clamp(26px, 4.2vw, 46px);
  line-height: 1.14;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.page-about .about-cta__text {
  margin: 16px 0 0;
  max-width: 52ch;
  font-size: var(--fs-base);
  line-height: 1.8;
  color: var(--text-dim);
}

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

@media (prefers-reduced-motion: reduce) {
  .page-about .about-tl__item--now::before {
    animation: none;
    box-shadow: 0 0 0 4px rgba(63, 224, 206, 0.2);
  }

  .page-about .role,
  .page-about .role__deliver,
  .page-about .dot,
  .page-about .dot-cluster,
  .page-about .about-rail__link {
    transition: none;
  }
}