.page-about {
  position: relative;
  display: block;
  background-color: var(--c-void);
  background-image:
    linear-gradient(to right, rgba(41, 231, 214, 0.045) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(41, 231, 214, 0.045) 1px, transparent 1px);
  background-size: 64px 64px;
  color: var(--c-text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  padding-block: clamp(16px, 2.6vw, 28px) clamp(48px, 7vw, 88px);
  overflow-x: clip;
  scroll-behavior: smooth;
}

.page-about a {
  color: inherit;
}

.page-about p {
  margin: 0 0 12px;
}

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

/* ---------- 面包屑 ---------- */
.page-about .about-crumbs {
  padding-block: 10px 18px;
}

/* ---------- 封面画板 ---------- */
.page-about .about-cover-wrap {
  margin-bottom: clamp(34px, 5vw, 64px);
}

.page-about .about-cover {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  border: var(--edge) solid var(--c-line-strong);
  background: var(--c-panel);
  box-shadow: 10px 10px 0 rgba(27, 42, 107, 0.5), var(--shadow-stack);
}

.page-about .about-cover__text {
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: clamp(22px, 3.4vw, 48px);
}

.page-about .about-eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.18em;
  color: var(--c-pulse);
}

.page-about h1 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(29px, 6.2vw, 52px);
  line-height: 1.16;
  letter-spacing: 0.01em;
}

.page-about .about-lede {
  max-width: 46ch;
  font-size: clamp(15px, 2.1vw, 17px);
  line-height: 1.85;
  color: var(--c-dim);
}

.page-about .about-chips {
  list-style: none;
  margin: 2px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .about-cover__hint {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 6px;
}

.page-about .about-cover__media {
  margin: 0;
  border-top: var(--edge) solid var(--c-line-strong);
  background: var(--c-rib);
  overflow: hidden;
}

.page-about .about-cover__media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  aspect-ratio: 14 / 9;
}

/* ---------- 通用区块 ---------- */
.page-about .about-block {
  margin-top: clamp(38px, 6vw, 78px);
  scroll-margin-top: calc(var(--strip-h) + 24px);
}

.page-about .about-block__head {
  max-width: 74ch;
  margin-bottom: clamp(18px, 3vw, 34px);
}

.page-about .about-h2 {
  margin: 8px 0 10px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(22px, 3.6vw, 30px);
  line-height: 1.3;
}

.page-about .about-intro {
  max-width: 64ch;
  color: var(--c-dim);
  line-height: 1.85;
}

/* ---------- 编年史 ---------- */
.page-about .about-chron {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0 0 8px;
  display: flex;
  gap: 10px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-rail__item {
  flex: 0 0 auto;
}

.page-about .about-rail__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border: var(--edge) solid var(--c-line);
  background: var(--c-panel);
  color: var(--c-dim);
  font-size: 13px;
  text-decoration: none;
  white-space: nowrap;
  transition: color var(--dur-fast) ease, border-color var(--dur-fast) ease,
    background-color var(--dur-fast) ease;
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--c-text);
  border-color: var(--c-neon);
  background: #0E1533;
  outline: none;
}

.page-about .about-rail__idx {
  font-size: 12px;
  font-weight: 700;
  color: var(--c-neon);
  letter-spacing: 0.08em;
}

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

.page-about .about-milestone {
  position: relative;
  border: var(--edge) solid var(--c-line);
  background: var(--c-panel);
  padding: clamp(20px, 3vw, 32px);
  scroll-margin-top: calc(var(--strip-h) + 96px);
  transition: border-color var(--dur) ease, background-color var(--dur) ease;
}

.page-about .about-milestone::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 4px;
  background: var(--c-deep);
  transition: background-color var(--dur) ease;
}

.page-about .about-milestone:target {
  border-color: var(--c-pulse);
  background: #0E1533;
}

.page-about .about-milestone:target::before {
  background: var(--c-pulse);
}

.page-about .about-milestone__stage {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--c-gold);
}

.page-about .about-milestone h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(19px, 2.5vw, 23px);
  line-height: 1.38;
}

.page-about .about-milestone p {
  color: var(--c-dim);
}

.page-about .about-note {
  margin-top: 16px;
  padding: 8px 0 8px 14px;
  border-left: 3px solid var(--c-alert);
  background: rgba(255, 106, 43, 0.05);
}

.page-about .about-note > summary {
  cursor: pointer;
  font-size: 13px;
  font-style: italic;
  color: var(--c-alert);
  letter-spacing: 0.02em;
}

.page-about .about-note > p {
  margin-top: 8px;
  font-size: 13px;
  font-style: italic;
  line-height: 1.75;
  color: var(--c-dim);
}

/* ---------- 岗位席位 ---------- */
.page-about .about-seats {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about .about-seat {
  border: var(--edge) solid var(--c-line);
  background: var(--c-panel);
}

.page-about .about-seat__sum {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 16px;
  cursor: pointer;
  list-style: none;
  border-left: 6px solid var(--c-deep);
  transition: border-color var(--dur-fast) ease, background-color var(--dur-fast) ease;
}

.page-about .about-seat__sum::-webkit-details-marker {
  display: none;
}

.page-about .about-seat[open] .about-seat__sum {
  border-left-color: var(--c-pulse);
}

.page-about .about-seat__sum:hover {
  background: #0E1533;
}

.page-about .about-seat__count {
  display: inline-flex;
  align-items: baseline;
  gap: 2px;
}

.page-about .about-seat__num {
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  color: var(--c-pulse);
}

.page-about .about-seat__unit {
  font-size: 12px;
  color: var(--c-mute);
}

.page-about .about-seat__name {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--c-text);
}

.page-about .about-seat__body {
  padding: 0 16px 18px;
  border-top: 1px solid var(--c-line);
}

.page-about .about-seat__body p {
  margin-top: 14px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--c-dim);
}

/* ---------- 流水线 ---------- */
.page-about .about-flow-media {
  margin: 0 0 clamp(18px, 3vw, 28px);
  border: var(--edge) solid var(--c-line);
  background: var(--c-rib);
  overflow: hidden;
}

.page-about .about-flow-media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  aspect-ratio: 12 / 5;
}

.page-about .about-flow {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  counter-reset: none;
}

.page-about .about-flow__step {
  border: var(--edge) solid var(--c-line);
  background: var(--c-panel);
  padding: 18px;
}

.page-about .about-flow__tag {
  display: inline-block;
  padding: 4px 14px 4px 10px;
  background: var(--c-neon);
  color: #FFFFFF;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.14em;
  clip-path: polygon(0 0, 100% 0, calc(100% - 10px) 100%, 0 100%);
}

.page-about .about-flow__title {
  margin: 12px 0 8px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.45;
}

.page-about .about-flow__step p {
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--c-dim);
}

/* ---------- 审校与勘误 ---------- */
.page-about .about-review {
  border: var(--edge) solid var(--c-line);
  background: var(--c-panel);
  padding: clamp(16px, 2.6vw, 26px);
}

.page-about .about-review__block {
  padding-top: 16px;
}

.page-about .about-review__block p {
  max-width: 72ch;
  color: var(--c-dim);
  line-height: 1.85;
}

/* ---------- 合规说明 ---------- */
.page-about .about-legal {
  border: var(--edge) solid var(--c-line-strong);
  background: linear-gradient(180deg, rgba(27, 42, 107, 0.38) 0%, rgba(11, 16, 36, 1) 62%);
  padding: clamp(20px, 3.2vw, 36px);
}

.page-about .about-legal__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.page-about .about-legal__item {
  padding-left: 14px;
  border-left: 2px solid var(--c-rib);
}

.page-about .about-legal__label {
  display: block;
  margin-bottom: 4px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--c-mute);
}

.page-about .about-legal__item p {
  color: var(--c-text);
  line-height: 1.8;
}

.page-about .about-legal__foot {
  margin-top: 22px;
  padding-top: 16px;
  border-top: 1px dashed var(--c-line-strong);
  font-size: 14px;
  color: var(--c-dim);
  line-height: 1.8;
}

.page-about .about-legal__foot a {
  color: var(--c-pulse);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 协作生态 ---------- */
.page-about .about-eco {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(20px, 3vw, 40px);
  align-items: center;
}

.page-about .about-eco__text p {
  max-width: 62ch;
  color: var(--c-dim);
  line-height: 1.85;
}

.page-about .about-eco__text a {
  color: var(--c-pulse);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .about-eco__figures {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  margin-top: 20px;
  padding-top: 18px;
  border-top: 2px solid var(--c-rib);
}

.page-about .about-eco__media {
  margin: 0;
  border: var(--edge) solid var(--c-line);
  background: var(--c-rib);
  overflow: hidden;
}

.page-about .about-eco__media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  aspect-ratio: 1 / 1;
}

/* ---------- 收尾 ---------- */
.page-about .about-closing {
  border: var(--edge) solid var(--c-line);
  border-left: 6px solid var(--c-neon);
  background: var(--c-panel);
  padding: clamp(20px, 3vw, 34px);
}

.page-about .about-closing p {
  max-width: 70ch;
  color: var(--c-dim);
  line-height: 1.85;
}

.page-about .about-closing__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 18px;
}

/* ---------- 平板及以上 ---------- */
@media (min-width: 720px) {
  .page-about .about-seats {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-legal__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px 26px;
  }

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

@media (min-width: 900px) {
  .page-about .about-cover {
    grid-template-columns: 7fr 5fr;
  }

  .page-about .about-cover__media {
    border-top: 0;
    border-left: var(--edge) solid var(--c-line-strong);
  }

  .page-about .about-chron {
    grid-template-columns: 216px minmax(0, 1fr);
    gap: clamp(28px, 4vw, 56px);
  }

  .page-about .about-rail {
    align-self: start;
    position: sticky;
    top: calc(var(--strip-h) + 76px);
  }

  .page-about .about-rail__list {
    flex-direction: column;
    gap: 16px;
    overflow: visible;
    padding: 4px 0 4px 22px;
    border-left: var(--edge) solid var(--c-rib);
  }

  .page-about .about-rail__item {
    position: relative;
    flex: 0 0 auto;
  }

  .page-about .about-rail__link {
    border: 0;
    background: transparent;
    padding: 2px 0;
    white-space: normal;
  }

  .page-about .about-rail__link::before {
    content: "";
    position: absolute;
    left: -27px;
    top: 7px;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--c-void);
    border: 2px solid var(--c-line-strong);
    transition: background-color var(--dur-fast) ease, border-color var(--dur-fast) ease,
      box-shadow var(--dur-fast) ease;
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    background: transparent;
    border-color: transparent;
  }

  .page-about .about-rail__link:hover::before,
  .page-about .about-rail__link:focus-visible::before {
    background: var(--c-pulse);
    border-color: var(--c-pulse);
    box-shadow: 0 0 0 4px rgba(41, 231, 214, 0.18);
  }

  .page-about .about-flow {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0;
    border: var(--edge) solid var(--c-line);
  }

  .page-about .about-flow__step {
    border: 0;
    border-left: var(--edge) solid var(--c-line);
  }

  .page-about .about-flow__step:first-child {
    border-left: 0;
  }

  .page-about .about-eco {
    grid-template-columns: minmax(0, 1fr) 320px;
  }
}

@media (min-width: 1180px) {
  .page-about .about-chron {
    grid-template-columns: 248px minmax(0, 1fr);
  }

  .page-about .about-eco {
    grid-template-columns: minmax(0, 1fr) 380px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about {
    scroll-behavior: auto;
  }

  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: 1ms !important;
    animation-duration: 1ms !important;
  }
}