.page-about {
  --about-rail-w: 132px;
  --about-card-line: rgba(217, 164, 65, .34);
  background-color: var(--c-ink);
  color: var(--c-fog);
  font-family: var(--font-body);
}

/* ---------- 共享节奏 ---------- */
.page-about .section {
  position: relative;
  padding: 68px 0;
}

@media (min-width: 900px) {
  .page-about .section {
    padding: 100px 0;
  }
}

.page-about .section-head {
  max-width: 74ch;
}

.page-about .section-index {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .22em;
  color: var(--c-amber);
}

.page-about .section-title {
  margin: 0 0 16px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(25px, 5vw, 38px);
  line-height: 1.3;
  letter-spacing: .06em;
  color: var(--c-fog);
}

.page-about .section--paper .section-title {
  color: var(--c-ink);
}

.page-about .section--paper {
  color: var(--c-ink);
}

.page-about .lede {
  margin: 0;
  font-size: 16.5px;
  line-height: 1.88;
  color: rgba(242, 245, 244, .78);
}

.page-about .section--paper .lede {
  color: rgba(11, 42, 58, .82);
}

.page-about .crumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  letter-spacing: .04em;
}

.page-about .crumbs__now {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .12em;
  color: var(--c-amber);
}

.page-about .note-hand {
  margin: 24px 0 0;
  font-family: var(--font-note);
  font-size: 16px;
  line-height: 1.8;
  color: rgba(240, 200, 120, .78);
}

.page-about .scope-links {
  margin-top: 24px;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding-bottom: 60px;
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding-bottom: 96px;
  }
}

.page-about .about-hero__wash {
  position: absolute;
  z-index: -1;
  inset: -34% -16% 24% 32%;
  background: linear-gradient(148deg,
      rgba(217, 164, 65, .22) 0%,
      rgba(58, 46, 92, .30) 42%,
      rgba(53, 224, 200, .10) 76%,
      rgba(53, 224, 200, 0) 100%);
  border-radius: 46% 54% 40% 60% / 56% 42% 58% 44%;
  transform: rotate(-18deg);
  pointer-events: none;
}

.page-about .about-hero__inner {
  display: grid;
  gap: 40px;
  align-items: center;
}

@media (min-width: 960px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.04fr) minmax(0, .96fr);
    gap: 56px;
  }
}

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

.page-about .about-hero .eyebrow {
  margin: 22px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .2em;
  color: var(--c-mist);
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(42px, 11vw, 88px);
  line-height: 1;
  letter-spacing: .14em;
  color: var(--c-fog);
}

.page-about .about-hero__lede {
  margin: 24px 0 0;
  max-width: 54ch;
  font-size: 16.5px;
  line-height: 1.9;
  color: rgba(242, 245, 244, .80);
}

.page-about .about-hero__facts {
  display: flex;
  flex-wrap: wrap;
  gap: 14px 36px;
  margin: 32px 0 0;
  padding: 20px 0 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.page-about .fact {
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.page-about .fact__num {
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 700;
  letter-spacing: .04em;
  color: var(--c-amber);
}

.page-about .fact__lbl {
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--c-mist);
}

.page-about .about-hero__figure {
  position: relative;
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--about-card-line);
  border-radius: 4px 4px 24px 4px;
  background: var(--c-ink-deep);
  box-shadow: var(--shadow-deep);
  clip-path: polygon(0 4%, 100% 0, 100% 96%, 0 100%);
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 1400 / 1000;
  object-fit: cover;
  filter: saturate(.62) contrast(1.06) brightness(.86);
}

.page-about .about-hero__figure::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(201, 212, 210, .13) 1px, transparent 1px),
    linear-gradient(90deg, rgba(201, 212, 210, .13) 1px, transparent 1px);
  background-size: 36px 36px;
  pointer-events: none;
}

.page-about .about-hero__tag {
  position: absolute;
  top: 18px;
  right: 18px;
  z-index: 2;
}

.page-about .about-hero__cap {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 2;
  margin: 0;
  padding: 12px 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--c-fog);
  background: linear-gradient(to top, rgba(6, 26, 38, .94), rgba(6, 26, 38, 0));
}

/* ---------- 江畔起点 ---------- */
.page-about .about-origin {
  overflow: hidden;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-origin::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-radial-gradient(circle at 86% 22%,
      rgba(201, 212, 210, .06) 0 1px,
      transparent 1px 58px);
  pointer-events: none;
}

.page-about .about-origin__grid {
  position: relative;
  display: grid;
  gap: 28px;
}

@media (min-width: 900px) {
  .page-about .about-origin__grid {
    grid-template-columns: minmax(0, 3.4fr) minmax(0, 8.6fr);
    gap: 56px;
    align-items: start;
  }

  .page-about .about-origin__aside {
    position: sticky;
    top: calc(var(--header-h-compact) + 36px);
  }
}

.page-about .about-origin__aside .section-title {
  margin-bottom: 0;
}

.page-about .about-origin__body p {
  margin: 0 0 20px;
  max-width: 68ch;
  font-size: 16.5px;
  line-height: 1.9;
  color: rgba(242, 245, 244, .80);
}

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

/* ---------- 坐标体系 ---------- */
.page-about .about-system {
  overflow: hidden;
}

.page-about .about-system__layout {
  display: grid;
  gap: 30px;
}

@media (min-width: 900px) {
  .page-about .about-system__layout {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: 52px;
    align-items: start;
  }
}

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

/* 年份刻度 */
.page-about .year-rail {
  display: none;
}

@media (min-width: 900px) {
  .page-about .year-rail {
    display: block;
    position: sticky;
    top: calc(var(--header-h-compact) + 34px);
    align-self: start;
  }
}

.page-about .year-rail__label {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .22em;
  color: var(--c-mist);
}

.page-about .year-rail__list {
  position: relative;
  margin: 0;
  padding: 0 0 0 20px;
  list-style: none;
}

.page-about .year-rail__list::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  bottom: 6px;
  width: 1px;
  background: linear-gradient(to bottom,
      var(--c-amber) 0%,
      rgba(217, 164, 65, .28) 56%,
      rgba(217, 164, 65, 0) 100%);
}

.page-about .year-rail__list li {
  position: relative;
}

.page-about .year-rail__list li::before {
  content: "";
  position: absolute;
  left: -20px;
  top: 16px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--c-amber);
  opacity: .45;
  transform: translateX(-50%);
  transition: opacity .22s var(--ease), transform .22s var(--ease);
}

.page-about .year-rail__tick {
  display: flex;
  flex-direction: column;
  gap: 3px;
  padding: 8px 0;
  text-decoration: none;
  color: var(--c-mist);
  transition: color .22s var(--ease);
}

.page-about .year-rail__num {
  font-family: var(--font-mono);
  font-size: 17px;
  font-weight: 700;
  letter-spacing: .06em;
  transition: color .22s var(--ease);
}

.page-about .year-rail__code {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .18em;
  color: rgba(127, 166, 166, .7);
}

.page-about .year-rail__tick:hover .year-rail__num,
.page-about .year-rail__tick:focus-visible .year-rail__num {
  color: var(--c-amber-bright);
}

.page-about .year-rail__list li:hover::before {
  opacity: 1;
  transform: translateX(-50%) scale(1.25);
}

/* 体系引言与信息图 */
.page-about .about-system__intro {
  display: grid;
  gap: 28px;
}

@media (min-width: 760px) {
  .page-about .about-system__intro {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, .88fr);
    gap: 36px;
    align-items: start;
  }
}

.page-about .about-system__lede {
  margin: 0;
  max-width: 52ch;
  font-size: 16.5px;
  line-height: 1.9;
  color: rgba(242, 245, 244, .78);
}

.page-about .about-figure {
  position: relative;
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 4px 4px 22px 4px;
  background: var(--c-ink);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  filter: saturate(.7) contrast(1.05) brightness(.9);
}

.page-about .about-figure::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(201, 212, 210, .12) 1px, transparent 1px),
    linear-gradient(90deg, rgba(201, 212, 210, .12) 1px, transparent 1px);
  background-size: 28px 28px;
  pointer-events: none;
}

.page-about .about-figure__cap {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 2;
  margin: 0;
  padding: 12px 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--c-fog);
  background: linear-gradient(to top, rgba(6, 26, 38, .94), rgba(6, 26, 38, 0));
}

/* 里程碑 */
.page-about .milestone-list {
  margin: 34px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 18px;
}

.page-about .milestone {
  position: relative;
  padding: 24px 26px 26px;
  border: 1px solid var(--line);
  border-left: 2px solid var(--c-amber);
  border-radius: 3px 18px 18px 3px;
  background: linear-gradient(155deg, rgba(58, 46, 92, .20), rgba(6, 26, 38, .66));
  scroll-margin-top: calc(var(--header-h-compact) + 34px);
  transition: border-color .24s var(--ease), background .24s var(--ease);
}

.page-about .milestone--content {
  border-left-color: var(--c-mist);
}

.page-about .milestone:target {
  border-color: rgba(240, 200, 120, .58);
  border-left-color: var(--c-amber-bright);
  background: linear-gradient(155deg, rgba(58, 46, 92, .34), rgba(6, 26, 38, .74));
}

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

.page-about .milestone__code {
  padding: 3px 8px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .18em;
  color: var(--c-amber-bright);
  border: 1px solid rgba(240, 200, 120, .42);
  border-radius: 3px;
}

.page-about .milestone__year {
  font-family: var(--font-mono);
  font-size: 21px;
  font-weight: 700;
  letter-spacing: .06em;
  color: var(--c-fog);
}

.page-about .milestone__title {
  margin: 12px 0 10px;
  font-family: var(--font-head);
  font-size: 18px;
  font-weight: 700;
  line-height: 1.5;
  letter-spacing: .03em;
  color: var(--c-fog);
}

.page-about .milestone p {
  margin: 0;
  max-width: 72ch;
  font-size: 15.5px;
  line-height: 1.86;
  color: rgba(242, 245, 244, .76);
}

/* ---------- 团队 ---------- */
.page-about .about-team .section-head {
  margin-bottom: 34px;
}

.page-about .team-layout {
  display: grid;
  gap: 26px;
}

@media (min-width: 900px) {
  .page-about .team-layout {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .team-visual {
    margin-top: 28px;
  }
}

.page-about .team-visual {
  position: relative;
  margin: 0;
  overflow: hidden;
  border: 1px solid rgba(217, 164, 65, .28);
  border-radius: 4px 4px 26px 4px;
  background: var(--c-ink);
}

.page-about .team-visual img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  filter: saturate(.55) contrast(1.08) brightness(.82);
}

.page-about .team-visual__cap {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  margin: 0;
  padding: 12px 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--c-fog);
  background: linear-gradient(to top, rgba(6, 26, 38, .94), rgba(6, 26, 38, 0));
}

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

.page-about .team-card {
  padding: 22px 24px 24px;
  border: 1px solid var(--line);
  border-radius: 16px 4px 16px 4px;
  background: linear-gradient(150deg, rgba(58, 46, 92, .28), rgba(11, 42, 58, .52));
  transition: border-color .24s var(--ease);
}

.page-about .team-card:hover {
  border-color: rgba(217, 164, 65, .44);
}

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

.page-about .team-card__role {
  margin: 0;
  font-family: var(--font-head);
  font-size: 14.5px;
  font-weight: 700;
  letter-spacing: .14em;
  color: var(--c-fog);
}

.page-about .team-card__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: .04em;
  color: var(--c-amber);
}

.page-about .team-card__desc {
  margin: 12px 0 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(242, 245, 244, .74);
}

/* ---------- 版本迭代 ---------- */
.page-about .about-versions {
  border-top: 1px solid var(--line-soft);
}

.page-about .about-versions .section-head {
  margin-bottom: 12px;
}

.page-about .version-list {
  margin: 34px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 22px;
}

.page-about .version-item {
  scroll-margin-top: calc(var(--header-h-compact) + 34px);
}

@media (min-width: 900px) {
  .page-about .version-item:nth-child(even) .version-card {
    transform: translateX(20px);
  }
}

.page-about .version-card {
  position: relative;
  padding: 34px 26px 24px;
  border: 1px solid var(--about-card-line);
  border-radius: 4px 20px 4px 20px;
  background: linear-gradient(160deg, rgba(58, 46, 92, .24), rgba(6, 26, 38, .72));
  box-shadow: var(--shadow-deep);
  transition: border-color .26s var(--ease), background .26s var(--ease);
}

.page-about .version-card::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 26px;
  width: 78px;
  height: 15px;
  border: 1px solid rgba(217, 164, 65, .36);
  border-bottom: 0;
  border-radius: 8px 8px 0 0;
  background: var(--c-indigo);
  transition: height .22s var(--ease);
}

.page-about .version-card:hover::before {
  height: 21px;
}

.page-about .version-card:target {
  border-color: rgba(240, 200, 120, .62);
}

.page-about .version-card__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 16px;
}

.page-about .version-card__code {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .2em;
  color: var(--c-amber);
}

.page-about .version-card__title {
  flex: 1 1 auto;
  margin: 0;
  font-family: var(--font-head);
  font-size: 19px;
  font-weight: 700;
  line-height: 1.4;
  letter-spacing: .04em;
  color: var(--c-fog);
}

.page-about .version-card__year {
  font-family: var(--font-mono);
  font-size: 25px;
  font-weight: 700;
  letter-spacing: .04em;
  color: rgba(240, 200, 120, .88);
}

.page-about .version-card__meta {
  display: grid;
  gap: 12px;
  margin: 20px 0 0;
  padding-top: 18px;
  border-top: 1px solid var(--line-soft);
}

@media (min-width: 720px) {
  .page-about .version-card__meta {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 22px;
  }
}

.page-about .version-card__meta dt {
  margin-bottom: 5px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--c-mist);
}

.page-about .version-card__meta dd {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.72;
  color: rgba(242, 245, 244, .78);
}

.page-about .version-card__note {
  margin: 16px 0 0;
  max-width: 72ch;
  font-size: 14.5px;
  line-height: 1.78;
  color: rgba(242, 245, 244, .72);
}

.page-about .version-card__anchor {
  display: inline-block;
  margin-top: 18px;
  padding-bottom: 2px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .16em;
  color: var(--c-mist);
  text-decoration: none;
  border-bottom: 1px dashed rgba(127, 166, 166, .5);
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.page-about .version-card__anchor:hover,
.page-about .version-card__anchor:focus-visible {
  color: var(--c-amber-bright);
  border-bottom-color: var(--c-amber-bright);
}

.page-about .about-versions__more {
  margin: 30px 0 0;
  max-width: 74ch;
  font-size: 15.5px;
  line-height: 1.86;
  color: rgba(242, 245, 244, .74);
}

.page-about .about-versions__more a {
  color: var(--c-amber-bright);
  text-decoration: none;
  border-bottom: 1px solid rgba(240, 200, 120, .4);
}

.page-about .about-versions__more a:hover,
.page-about .about-versions__more a:focus-visible {
  border-bottom-color: var(--c-amber-bright);
}

/* ---------- 合作与自查 ---------- */
.page-about .about-partners__grid {
  display: grid;
  gap: 32px;
}

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

.page-about .about-partners__main p {
  max-width: 60ch;
  font-size: 16px;
  line-height: 1.88;
  color: rgba(11, 42, 58, .82);
}

.page-about .partner-list {
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
  overflow: hidden;
  border: 1px solid rgba(11, 42, 58, .18);
  border-radius: 4px;
  background: rgba(11, 42, 58, .12);
  display: grid;
  gap: 1px;
}

.page-about .partner-list li {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding: 14px 18px;
  background: var(--c-paper);
}

.page-about .partner-list__code {
  min-width: 74px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .12em;
  color: #8a6516;
}

.page-about .partner-list__name {
  font-size: 15px;
  font-weight: 600;
  letter-spacing: .03em;
  color: var(--c-ink);
}

.page-about .checklist {
  padding: 26px 26px 28px;
  border: 1px solid rgba(217, 164, 65, .44);
  border-radius: 4px 22px 4px 22px;
  background: rgba(255, 255, 255, .62);
}

.page-about .checklist__title {
  margin: 0;
  font-family: var(--font-head);
  font-size: 18px;
  font-weight: 700;
  letter-spacing: .06em;
  color: var(--c-ink);
}

.page-about .checklist__lede {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: rgba(11, 42, 58, .7);
}

.page-about .checklist__list {
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 14px;
}

.page-about .checklist__item {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  padding-bottom: 14px;
  border-bottom: 1px dashed rgba(11, 42, 58, .18);
}

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

.page-about .checklist__num {
  padding-top: 2px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .12em;
  color: #8a6516;
}

.page-about .checklist__name {
  margin: 0;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: .03em;
  color: var(--c-ink);
}

.page-about .checklist__desc {
  margin: 5px 0 0;
  font-size: 14px;
  line-height: 1.78;
  color: rgba(11, 42, 58, .74);
}

/* ---------- 口径 ---------- */
.page-about .about-scope {
  overflow: hidden;
}

.page-about .scope-panel {
  position: relative;
  max-width: 78ch;
  padding: 32px 26px 30px;
  border: 1px solid var(--line);
  border-left: 2px solid rgba(217, 164, 65, .7);
  border-radius: 3px 26px 3px 26px;
  background: linear-gradient(155deg, rgba(58, 46, 92, .26), rgba(11, 42, 58, .54));
}

.page-about .scope-panel p {
  margin: 0 0 16px;
  font-size: 15.5px;
  line-height: 1.88;
  color: rgba(242, 245, 244, .78);
}

.page-about .scope-panel p:last-of-type {
  margin-bottom: 0;
}

@media (min-width: 720px) {
  .page-about .scope-panel {
    padding: 40px 40px 36px;
  }
}

/* ---------- 焦点可达性 ---------- */
.page-about a:focus-visible,
.page-about button:focus-visible {
  outline: 2px solid var(--c-amber);
  outline-offset: 3px;
  border-radius: 2px;
}

/* ---------- 减少动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .version-card,
  .page-about .version-card::before,
  .page-about .team-card,
  .page-about .milestone,
  .page-about .year-rail__tick {
    transition: none;
  }

  .page-about .version-item:nth-child(even) .version-card {
    transform: none;
  }
}