.page-about {
  --ab-tone-a: #0C231D;
  --ab-tone-b: #123027;
  --ab-tone-c: #0A1E19;
  --ab-edge: rgba(154, 163, 160, 0.2);
  --ab-shadow: 0 22px 48px -32px rgba(0, 0, 0, 0.95);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-block: clamp(24px, 4vw, 44px) clamp(40px, 6vw, 76px);
  background: var(--c-base);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -20%;
  right: -18%;
  width: min(760px, 86%);
  height: 122%;
  background: linear-gradient(
    162deg,
    rgba(44, 122, 85, 0.86) 0%,
    rgba(20, 72, 58, 0.44) 46%,
    rgba(10, 30, 25, 0) 78%
  );
  clip-path: polygon(36% 0%, 100% 0%, 100% 100%, 0% 74%);
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--c-line-soft) 1px, transparent 1px),
    linear-gradient(90deg, var(--c-line-soft) 1px, transparent 1px);
  background-size: 72px 72px;
  opacity: 0.55;
  pointer-events: none;
  mask-image: linear-gradient(180deg, #000 0%, transparent 78%);
}

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

/* ---------- 面包屑 ---------- */
.page-about .crumbs {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--c-text-dim);
  margin-bottom: clamp(18px, 3vw, 28px);
}

.page-about .crumbs ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .crumbs li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.page-about .crumbs li + li::before {
  content: "/";
  color: var(--c-concrete);
}

.page-about .crumbs a {
  color: var(--c-neon);
  text-decoration: none;
}

.page-about .crumbs a:hover,
.page-about .crumbs a:focus-visible {
  text-decoration: underline;
}

/* ---------- 首屏文字 ---------- */
.page-about .about-hero .eyebrow {
  color: var(--c-neon);
}

.page-about .about-hero__title {
  margin: 0 0 clamp(18px, 2.6vw, 28px);
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.1rem, 6.4vw, 5rem);
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: var(--c-text);
  max-width: 20ch;
}

.page-about .about-hero__split {
  display: grid;
  gap: clamp(18px, 3vw, 32px);
  max-width: 62rem;
}

.page-about .about-hero__lead {
  margin: 0;
  font-size: clamp(1rem, 1.6vw, 1.15rem);
  line-height: 1.78;
  color: var(--c-text-dim);
  max-width: 46ch;
}

.page-about .about-hero__marks {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
  align-self: start;
}

.page-about .about-hero__marks li {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  padding: 6px 12px;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-s);
  color: var(--c-text);
  background: rgba(62, 224, 192, 0.06);
}

/* ---------- 首屏数据条 ---------- */
.page-about .about-figures {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(30px, 5vw, 56px) 0 0;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-m);
  overflow: hidden;
  max-width: 62rem;
}

.page-about .about-figure {
  display: grid;
  gap: 4px;
  padding: 16px 14px;
  background: #0D251F;
}

.page-about .about-figure__key {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--c-concrete);
  text-transform: uppercase;
}

.page-about .about-figure__value {
  margin: 0;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.6rem, 3.4vw, 2.4rem);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--c-data);
}

.page-about .about-figure__note {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--c-text-dim);
}

/* ---------- 时间轴区块 ---------- */
.page-about .about-arc {
  background:
    radial-gradient(110% 70% at 8% 0%, rgba(20, 72, 58, 0.6), transparent 62%),
    var(--c-base);
}

.page-about .about-grid {
  align-items: start;
  row-gap: clamp(26px, 4vw, 46px);
}

.page-about .about-rail {
  grid-column: span 12;
}

.page-about .about-body {
  grid-column: span 12;
  display: grid;
  gap: clamp(18px, 2.6vw, 28px);
}

.page-about .about-rail__label {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--c-concrete);
  text-transform: uppercase;
}

.page-about .about-rail__list {
  display: flex;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0 0 8px;
  overflow-x: auto;
  scrollbar-width: thin;
  scrollbar-color: var(--c-concrete) transparent;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-rail__link {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 9px 12px;
  border-inline-start: 2px solid var(--c-line);
  border-radius: 0 var(--radius-s) var(--radius-s) 0;
  background: rgba(255, 255, 255, 0.02);
  color: var(--c-text-dim);
  text-decoration: none;
  white-space: nowrap;
  transition: border-color var(--dur), color var(--dur), background var(--dur);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  border-inline-start-color: var(--c-neon);
  color: var(--c-text);
  background: rgba(62, 224, 192, 0.08);
}

.page-about .about-rail__no {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--c-orange);
}

.page-about .about-rail__span {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
}

/* ---------- 阶段卡 ---------- */
.page-about .about-stage {
  padding: clamp(18px, 3vw, 32px);
  border: 1px solid var(--ab-edge);
  border-radius: var(--radius-l);
  scroll-margin-top: 148px;
}

.page-about .about-stage--a { background: var(--ab-tone-a); }
.page-about .about-stage--b { background: var(--ab-tone-b); }
.page-about .about-stage--c { background: var(--ab-tone-c); }

.page-about .about-stage__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 14px;
  margin-bottom: 14px;
}

.page-about .about-stage__years {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.08em;
  color: var(--c-data);
}

.page-about .about-stage__title {
  flex-basis: 100%;
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.25rem, 2.8vw, 1.85rem);
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--c-text);
}

.page-about .about-stage__text {
  margin: 0 0 12px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--c-text-dim);
  max-width: 46ch;
}

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

.page-about .about-stage__text--strong {
  color: var(--c-text);
  padding-inline-start: 14px;
  border-inline-start: 2px solid var(--c-turf);
}

/* ---------- 通用图片 ---------- */
.page-about .about-figure {
  margin: clamp(18px, 2.6vw, 28px) 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  border-radius: var(--radius-m);
  border: 1px solid var(--c-line-soft);
  filter: saturate(0.92);
}

.page-about .about-figure figcaption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  line-height: 1.65;
  color: var(--c-text-dim);
}

.page-about .about-figure--wide img {
  aspect-ratio: 4 / 3;
}

.page-about .about-figure--side {
  margin: 0;
}

/* ---------- 俱乐部简史 ---------- */
.page-about .about-anatomy {
  background: linear-gradient(180deg, var(--c-home) 0%, #103A2D 58%, var(--c-home) 100%);
  position: relative;
  overflow: hidden;
}

.page-about .about-anatomy::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(
    135deg,
    rgba(255, 255, 255, 0.028) 0px,
    rgba(255, 255, 255, 0.028) 1px,
    transparent 1px,
    transparent 9px
  );
  pointer-events: none;
}

.page-about .about-anatomy .shell {
  position: relative;
  z-index: 1;
}

.page-about .about-anatomy__intro {
  max-width: 52ch;
  margin-bottom: clamp(26px, 4vw, 44px);
}

.page-about .about-threads {
  display: grid;
  gap: 1px;
  list-style: none;
  margin: 0 0 clamp(24px, 3.4vw, 38px);
  padding: 0;
  background: rgba(243, 241, 234, 0.16);
  border: 1px solid rgba(243, 241, 234, 0.18);
  border-radius: var(--radius-l);
  overflow: hidden;
}

.page-about .about-thread {
  background: rgba(10, 30, 25, 0.42);
  padding: clamp(16px, 2.6vw, 24px);
  display: grid;
  gap: 6px;
  transition: background var(--dur);
}

.page-about .about-thread:hover {
  background: rgba(10, 30, 25, 0.62);
}

.page-about .about-thread__no {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--c-orange);
}

.page-about .about-thread__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.125rem;
  letter-spacing: -0.01em;
  color: var(--c-text);
}

.page-about .about-thread__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--c-text-dim);
}

.page-about .about-anatomy__linkline {
  margin: 0 0 clamp(20px, 3vw, 34px);
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--c-text-dim);
  max-width: 46ch;
}

.page-about .about-anatomy__linkline a {
  color: var(--c-neon);
  text-decoration: none;
  border-bottom: 1px solid rgba(62, 224, 192, 0.45);
  padding-bottom: 1px;
}

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

/* ---------- 档案构成（标签页） ---------- */
.page-about .about-samples {
  background: var(--c-base);
}

.page-about .about-tabs {
  margin-top: clamp(22px, 3vw, 34px);
}

.page-about .about-tabs .tabs__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 0;
}

.page-about .about-panel {
  padding: clamp(18px, 3vw, 30px);
  background: var(--ab-tone-a);
  border: 1px solid var(--ab-edge);
  border-radius: var(--radius-l);
  margin-top: 14px;
}

.page-about .about-panel__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.15rem, 2.4vw, 1.5rem);
  letter-spacing: -0.01em;
  color: var(--c-text);
}

.page-about .about-panel__text {
  margin: 0 0 16px;
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--c-text-dim);
  max-width: 46ch;
}

.page-about .about-panel__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--c-line-soft);
  border-radius: var(--radius-s);
  overflow: hidden;
}

.page-about .about-panel__list li {
  background: #0E2721;
  padding: 14px 16px;
  display: grid;
  gap: 5px;
}

.page-about .about-panel__key {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--c-data);
}

.page-about .about-panel__val {
  font-size: 15px;
  line-height: 1.72;
  color: var(--c-text-dim);
}

/* ---------- 编辑与校对 ---------- */
.page-about .about-team {
  background:
    radial-gradient(90% 70% at 88% 10%, rgba(44, 122, 85, 0.36), transparent 66%),
    var(--c-base);
}

.page-about .about-team__grid {
  display: grid;
  gap: clamp(24px, 3.4vw, 44px);
}

.page-about .about-pipeline {
  list-style: none;
  margin: clamp(18px, 2.6vw, 28px) 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .about-pipeline li {
  position: relative;
  padding: 16px 18px 16px 22px;
  border: 1px solid var(--ab-edge);
  border-radius: var(--radius-m);
  background: rgba(18, 48, 39, 0.6);
  display: grid;
  gap: 5px;
  transition: transform var(--dur), border-color var(--dur);
}

.page-about .about-pipeline li::before {
  content: "";
  position: absolute;
  inset-block: 14px;
  inset-inline-start: 0;
  width: 3px;
  border-radius: 3px;
  background: linear-gradient(180deg, var(--c-neon), var(--c-turf));
}

.page-about .about-pipeline li:hover {
  transform: translateY(-2px);
  border-color: rgba(62, 224, 192, 0.5);
}

.page-about .about-pipeline__step {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--c-concrete);
}

.page-about .about-pipeline__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.0625rem;
  color: var(--c-text);
}

.page-about .about-pipeline__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--c-text-dim);
}

/* ---------- 资料互换 ---------- */
.page-about .about-partners {
  background: var(--c-base);
}

.page-about .about-partners__grid {
  display: grid;
  gap: 14px;
  margin-top: clamp(20px, 3vw, 32px);
}

.page-about .about-partner {
  padding: clamp(18px, 2.8vw, 26px);
  border: 1px solid var(--ab-edge);
  border-radius: var(--radius-l);
  background: var(--ab-tone-b);
  display: grid;
  gap: 8px;
  align-content: start;
}

.page-about .about-partner--accent {
  background: linear-gradient(150deg, var(--c-turf) 0%, #1C5B41 100%);
  border-color: rgba(62, 224, 192, 0.35);
}

.page-about .about-partner__count {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(2rem, 5vw, 3.2rem);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--c-orange);
}

.page-about .about-partner__badge {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--c-neon);
  padding: 5px 10px;
  border: 1px solid rgba(62, 224, 192, 0.5);
  border-radius: var(--radius-s);
  justify-self: start;
}

.page-about .about-partner__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.0625rem;
  line-height: 1.4;
  color: var(--c-text);
}

.page-about .about-partner__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.74;
  color: var(--c-text-dim);
}

.page-about .about-partner--accent .about-partner__text {
  color: rgba(234, 242, 238, 0.82);
}

.page-about .about-partners__note {
  margin: clamp(20px, 3vw, 30px) 0 0;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--c-text-dim);
  max-width: 48ch;
}

.page-about .about-partners__note a {
  color: var(--c-neon);
  text-decoration: none;
  border-bottom: 1px solid rgba(62, 224, 192, 0.45);
}

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

/* ---------- 站点信息 ---------- */
.page-about .about-site {
  padding-block: clamp(42px, 7vw, 88px);
  background:
    linear-gradient(180deg, var(--c-base) 0%, #08211B 100%);
}

.page-about .about-plate {
  position: relative;
  background: var(--c-paper);
  color: var(--c-ink);
  border-radius: var(--radius-l);
  padding: clamp(22px, 4vw, 44px);
  box-shadow: var(--ab-shadow);
  overflow: hidden;
  max-width: 60rem;
}

.page-about .about-plate::after {
  content: "";
  position: absolute;
  top: -30%;
  right: -12%;
  width: 46%;
  height: 150%;
  background: linear-gradient(150deg, rgba(44, 122, 85, 0.22), rgba(255, 107, 53, 0.12) 70%, transparent);
  clip-path: polygon(30% 0%, 100% 0%, 100% 100%, 0% 72%);
  pointer-events: none;
}

.page-about .about-plate > * {
  position: relative;
  z-index: 1;
}

.page-about .about-plate__tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  padding: 5px 11px;
  border: 1px solid rgba(10, 30, 25, 0.35);
  border-radius: var(--radius-s);
  color: rgba(10, 30, 25, 0.72);
  margin-bottom: 14px;
}

.page-about .about-plate__title {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.5rem, 3.6vw, 2.4rem);
  letter-spacing: -0.02em;
  line-height: 1.18;
  color: var(--c-ink);
}

.page-about .about-plate__text {
  margin: 0 0 20px;
  font-size: 16px;
  line-height: 1.78;
  color: rgba(10, 30, 25, 0.78);
  max-width: 46ch;
}

.page-about .about-plate__text--tight {
  margin-bottom: 18px;
}

.page-about .about-plate__meta {
  display: grid;
  gap: 1px;
  margin: 0 0 22px;
  background: rgba(10, 30, 25, 0.16);
  border: 1px solid rgba(10, 30, 25, 0.16);
  border-radius: var(--radius-s);
  overflow: hidden;
}

.page-about .about-plate__meta > div {
  background: var(--c-paper);
  padding: 12px 14px;
  display: grid;
  gap: 3px;
}

.page-about .about-plate__meta dt {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: rgba(10, 30, 25, 0.55);
}

.page-about .about-plate__meta dd {
  margin: 0;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.01em;
  color: var(--c-ink);
  word-break: break-word;
}

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

  .page-about .about-figure {
    padding: 18px 18px;
  }

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

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

  .page-about .about-partner--accent {
    grid-column: span 2;
  }

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

@media (min-width: 940px) {
  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    align-items: start;
  }

  .page-about .about-figure--side {
    position: sticky;
    top: 132px;
  }

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

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

  .page-about .about-partner--accent {
    grid-column: span 1;
  }
}

@media (min-width: 1000px) {
  .page-about .about-rail {
    grid-column: span 3;
    position: sticky;
    top: 132px;
  }

  .page-about .about-body {
    grid-column: span 9;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    overflow: visible;
    padding-bottom: 0;
    gap: 4px;
  }

  .page-about .about-rail__link {
    padding: 11px 14px;
  }

  .page-about .about-stage__text {
    max-width: 44ch;
  }
}

@media (min-width: 1180px) {
  .page-about .about-hero__split {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    align-items: end;
  }

  .page-about .about-hero__marks {
    justify-content: flex-end;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .about-thread,
  .page-about .about-pipeline li {
    transition: none;
  }

  .page-about .about-pipeline li:hover {
    transform: none;
  }
}