.page-about {
  --about-rail: 200px;
  --about-gap: clamp(22px, 3.4vw, 54px);
  background: var(--ink-900);
  color: var(--paper);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(22px, 4vw, 44px) 0 clamp(34px, 6vw, 72px);
  isolation: isolate;
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(120% 88% at 88% -12%, rgba(184, 245, 60, 0.1), transparent 58%),
    var(--ink-800);
  clip-path: polygon(0 0, 100% 0, 100% 92%, 0 100%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--lime) 0%, var(--ink-600) 34%, transparent 100%);
  opacity: 0.7;
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(22px, 4vw, 44px);
  margin-top: clamp(16px, 2.6vw, 28px);
}

.page-about .about-hero__title {
  margin: 10px 0 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(30px, 6.6vw, 60px);
  line-height: 1.06;
  letter-spacing: -0.01em;
  color: var(--paper);
  max-width: 16em;
}

.page-about .about-hero__lead {
  margin: clamp(14px, 2.4vw, 22px) 0 0;
  max-width: 58ch;
  font-size: clamp(15px, 1.7vw, 17px);
  line-height: 1.8;
  color: var(--paper);
  opacity: 0.92;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: clamp(18px, 3vw, 28px);
}

.page-about .about-hero__figure {
  aspect-ratio: 3 / 2;
  align-self: end;
  border: 1px solid var(--ink-600);
}

.page-about .about-hero__figure img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  filter: saturate(0.72) brightness(0.78);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(26px, 4vw, 46px) 0 0;
  background: var(--ink-600);
  border: 1px solid var(--ink-600);
}

.page-about .about-fact {
  background: var(--ink-900);
  padding: 14px 16px 16px;
}

.page-about .about-fact__label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-fact__value {
  margin: 8px 0 0;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(24px, 4vw, 32px);
  line-height: 1;
  color: var(--lime);
  font-variant-numeric: tabular-nums;
}

.page-about .about-fact__unit {
  margin-left: 3px;
  font-size: 12px;
  font-weight: 500;
  color: var(--muted);
  letter-spacing: 0.04em;
}

/* ---------- 主体骨架 ---------- */
.page-about .about-shell {
  display: grid;
  gap: var(--about-gap);
  padding: clamp(28px, 5vw, 56px) 0 clamp(40px, 7vw, 96px);
}

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

.page-about .about-rail__title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--moss);
}

.page-about .about-rail__list {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding: 0 0 8px;
  scrollbar-width: thin;
}

.page-about .about-rail__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  flex: none;
  padding: 9px 13px;
  font-size: 13px;
  line-height: 1.2;
  text-decoration: none;
  color: var(--muted);
  background: var(--ink-800);
  border: 1px solid var(--ink-600);
  border-radius: var(--radius);
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease), background 0.18s var(--ease);
}

.page-about .about-rail__idx {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--moss);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--paper);
  border-color: var(--lime);
}

.page-about .about-rail__link[aria-current="true"] {
  color: var(--ink-900);
  background: var(--lime);
  border-color: var(--lime);
}

.page-about .about-rail__link[aria-current="true"] .about-rail__idx {
  color: rgba(7, 19, 15, 0.6);
}

.page-about .about-rail__note {
  margin: 12px 0 0;
  font-size: 12px;
  line-height: 1.6;
  color: var(--moss);
}

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

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  padding: clamp(26px, 4.6vw, 54px) 0;
  border-top: 1px solid var(--ink-600);
  scroll-margin-top: calc(var(--header-h) + 20px);
}

.page-about .about-chapter:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .about-chapter__head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: clamp(14px, 2.2vw, 22px);
}

.page-about .about-chapter__index {
  flex: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--lime);
}

.page-about .about-chapter__title {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(21px, 3.4vw, 32px);
  line-height: 1.18;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-subtitle {
  margin: clamp(20px, 3vw, 30px) 0 12px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(16px, 2vw, 19px);
  line-height: 1.3;
  color: var(--paper);
}

.page-about .about-prose p {
  max-width: 68ch;
  margin: 0 0 1em;
  font-size: clamp(15px, 1.6vw, 16.5px);
  line-height: 1.85;
  color: var(--paper);
}

.page-about .about-prose__tail {
  max-width: 68ch;
  margin: 16px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-prose__tail a,
.page-about .about-chapter a {
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid var(--lime-dim);
}

.page-about .about-prose__tail a:hover,
.page-about .about-chapter a:hover {
  border-bottom-color: var(--lime);
}

/* ---------- 三段流程 ---------- */
.page-about .flow {
  display: grid;
  gap: 14px;
  margin: clamp(18px, 2.6vw, 24px) 0 0;
}

.page-about .flow__step {
  position: relative;
  padding: 20px 22px 18px;
  background: var(--ink-800);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 15px), calc(100% - 15px) 100%, 0 100%);
  transition: background 0.18s var(--ease);
}

.page-about .flow__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--teal);
}

.page-about .flow__name {
  margin: 8px 0 8px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 18px;
  line-height: 1.2;
  color: var(--paper);
}

.page-about .flow__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .flow__out {
  margin: 14px 0 0;
  padding-top: 11px;
  border-top: 1px dashed var(--ink-600);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.03em;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .flow__out b {
  color: var(--lime);
  font-weight: 700;
  margin-right: 6px;
}

/* 图文分栏 */
.page-about .about-split {
  display: grid;
  gap: clamp(16px, 2.6vw, 28px);
  margin-top: clamp(22px, 3.4vw, 32px);
}

.page-about .about-split__text p {
  max-width: 60ch;
  margin: 0 0 1em;
  font-size: clamp(15px, 1.6vw, 16px);
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-split__figure {
  aspect-ratio: 4 / 5;
  border: 1px solid var(--ink-600);
  max-width: 340px;
}

.page-about .about-split__figure img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.7) brightness(0.76);
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  gap: 1px;
  margin-top: clamp(18px, 2.6vw, 26px);
  background: var(--ink-600);
  border: 1px solid var(--ink-600);
}

.page-about .team-grid__cell {
  background: var(--ink-800);
  padding: 16px 18px 18px;
  transition: background 0.18s var(--ease);
}

.page-about .team-grid__name {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--teal);
}

.page-about .team-grid__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 里程碑 ---------- */
.page-about .about-band {
  aspect-ratio: 2 / 1;
  margin: 0 0 clamp(20px, 3vw, 30px);
  border: 1px solid var(--ink-600);
}

.page-about .about-band img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.65) brightness(0.7);
}

.page-about .milestones {
  position: relative;
  padding-left: 26px;
}

.page-about .milestones::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(to bottom, var(--lime) 0%, var(--ink-600) 26%, var(--ink-600) 100%);
}

.page-about .milestone {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 18px;
  padding: 0 0 clamp(20px, 3vw, 28px);
}

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

.page-about .milestone::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 8px;
  width: 11px;
  height: 11px;
  background: var(--ink-900);
  border: 1px solid var(--ink-600);
  transform: rotate(45deg);
  transition: background 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .milestone:hover::before {
  background: var(--lime-dim);
  border-color: var(--lime);
}

.page-about .milestone--now::before {
  background: var(--lime);
  border-color: var(--lime);
}

.page-about .milestone__year {
  flex: none;
  min-width: 62px;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(17px, 2.2vw, 21px);
  line-height: 1.2;
  color: var(--lime);
  font-variant-numeric: tabular-nums;
}

.page-about .milestone__body {
  flex: 1 1 260px;
  min-width: 0;
}

.page-about .milestone__name {
  margin: 0 0 4px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 15.5px;
  line-height: 1.35;
  color: var(--paper);
}

.page-about .milestone__text {
  margin: 0;
  max-width: 56ch;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 覆盖范围 ---------- */
.page-about .about-stats {
  display: grid;
  gap: 1px;
  margin: 0 0 clamp(18px, 2.6vw, 26px);
  background: var(--ink-600);
  border-top: 1px solid var(--ink-600);
  border-bottom: 1px solid var(--ink-600);
}

.page-about .about-stat {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 16px;
  padding: 14px 16px;
  background: var(--ink-800);
}

.page-about .about-stat__num {
  flex: none;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(28px, 4.6vw, 40px);
  line-height: 1;
  color: var(--paper);
  font-variant-numeric: tabular-nums;
}

.page-about .about-stat__note {
  flex: 1 1 220px;
  min-width: 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .about-rules {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--ink-600);
}

.page-about .about-rules__item {
  display: grid;
  gap: 4px;
  padding: 13px 0;
  border-bottom: 1px solid var(--ink-600);
}

.page-about .about-rules__key {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.1em;
  color: var(--orange);
}

.page-about .about-rules__val {
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--paper);
}

/* ---------- 引用 ---------- */
.page-about .about-quote {
  margin: clamp(20px, 3vw, 28px) 0 0;
  padding: 20px 22px;
  background: var(--ink-800);
  border-left: 2px solid var(--lime);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 14px), calc(100% - 14px) 100%, 0 100%);
}

.page-about .about-quote__text {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(16px, 2.2vw, 20px);
  line-height: 1.5;
  color: var(--paper);
}

.page-about .about-quote__cite {
  display: block;
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-style: normal;
  letter-spacing: 0.08em;
  color: var(--moss);
}

/* ---------- 更新完成 ---------- */
.page-about .about-steps {
  list-style: none;
  margin: 16px 0 0;
  padding: 0;
  counter-reset: step;
}

.page-about .about-steps__item {
  display: flex;
  gap: 14px;
  padding: 15px 0;
  border-top: 1px solid var(--ink-600);
}

.page-about .about-steps__item:last-child {
  border-bottom: 1px solid var(--ink-600);
}

.page-about .about-steps__num {
  flex: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--teal);
  padding-top: 3px;
}

.page-about .about-steps__text {
  margin: 0;
  max-width: 62ch;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--paper);
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  margin-top: clamp(26px, 4vw, 46px);
  padding: clamp(24px, 4vw, 40px);
  background:
    radial-gradient(110% 120% at 100% 0%, rgba(184, 245, 60, 0.12), transparent 62%),
    var(--ink-800);
  border: 1px solid var(--ink-600);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
}

.page-about .about-cta__title {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(20px, 3.2vw, 28px);
  line-height: 1.2;
  color: var(--paper);
}

.page-about .about-cta__text {
  margin: 10px 0 0;
  max-width: 56ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 20px;
}

/* ---------- 平板与桌面 ---------- */
@media (min-width: 700px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

  .page-about .about-stat {
    padding: 16px 20px;
  }
}

@media (min-width: 860px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    align-items: end;
  }

  .page-about .about-hero__figure {
    margin-bottom: 4px;
  }

  .page-about .flow {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1px;
    background: var(--ink-600);
  }

  .page-about .flow__step {
    clip-path: none;
  }

  .page-about .flow__step + .flow__step {
    position: relative;
    padding-left: 34px;
  }

  .page-about .flow__step + .flow__step::before {
    content: "";
    position: absolute;
    left: 16px;
    top: 14%;
    height: 72%;
    width: 1px;
    background: var(--ink-600);
    transform: skewX(-16deg);
  }

  .page-about .about-split {
    grid-template-columns: minmax(0, 1.55fr) minmax(0, 0.9fr);
    align-items: start;
  }

  .page-about .about-split__figure {
    max-width: none;
  }

  .page-about .about-rules__item {
    grid-template-columns: 88px minmax(0, 1fr);
    gap: 16px;
    align-items: baseline;
  }
}

@media (min-width: 980px) {
  .page-about .about-shell {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 26px);
    align-self: start;
  }

  .page-about .about-rail__list {
    display: grid;
    gap: 2px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-rail__link {
    justify-content: flex-start;
    width: 100%;
    background: transparent;
    border-color: transparent;
    border-left: 2px solid transparent;
    border-radius: 0;
    padding: 8px 10px;
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    background: var(--ink-800);
    border-color: var(--ink-600);
    border-left-color: var(--lime);
  }

  .page-about .about-rail__link[aria-current="true"] {
    background: var(--ink-800);
    border-color: var(--ink-600);
    border-left-color: var(--lime);
    color: var(--lime);
  }

  .page-about .about-rail__link[aria-current="true"] .about-rail__idx {
    color: var(--lime);
  }

  .page-about .about-rail__note {
    border-top: 1px solid var(--ink-600);
    padding-top: 12px;
  }

  .page-about .about-chapter__title {
    font-size: clamp(24px, 2.6vw, 32px);
  }
}

@media (hover: hover) {
  .page-about .flow__step:hover {
    background: var(--ink-700);
  }

  .page-about .team-grid__cell:hover {
    background: var(--ink-700);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .flow__step,
  .page-about .team-grid__cell,
  .page-about .about-rail__link,
  .page-about .milestone::before {
    transition: none;
  }
}