.page-about {
  background: var(--ink-900);
  color: var(--frost);
  font-family: var(--font-sans);
  overflow-x: hidden;
}

.page-about .about-crumb {
  padding-top: var(--space-3);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: var(--space-4) 0 var(--space-5);
  border-bottom: 1px solid var(--line-soft);
  background:
    radial-gradient(120% 90% at 84% 0%, rgba(92, 255, 177, 0.13), transparent 58%),
    linear-gradient(180deg, var(--ink-950) 0%, var(--ink-900) 100%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: 0.28;
  background-image:
    repeating-linear-gradient(to right, var(--line-soft) 0 1px, transparent 1px 80px),
    repeating-linear-gradient(to bottom, var(--line-soft) 0 1px, transparent 1px 80px);
  -webkit-mask-image: linear-gradient(180deg, #000 0%, transparent 82%);
  mask-image: linear-gradient(180deg, #000 0%, transparent 82%);
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  gap: var(--space-4);
}

.page-about .about-hero__eyebrow {
  margin: 0 0 var(--space-2);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--mint);
  text-transform: uppercase;
}

.page-about .about-hero__lead h1 {
  margin: 0 0 var(--space-3);
  font-size: clamp(28px, 7.4vw, 54px);
  line-height: 1.14;
  letter-spacing: -0.02em;
  font-weight: 800;
  color: var(--frost);
}

.page-about .about-hero__text {
  margin: 0 0 12px;
  max-width: 54ch;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(234, 246, 239, 0.84);
}

.page-about .about-hero__text--sub {
  padding-left: 14px;
  border-left: 2px solid var(--line);
  font-size: 14px;
  color: var(--mist);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: var(--space-3);
}

/* 历程索引卡 */
.page-about .about-index {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: var(--space-3);
  background: linear-gradient(180deg, rgba(11, 42, 33, 0.94), rgba(7, 28, 22, 0.94));
  box-shadow: 0 24px 48px -38px rgba(0, 0, 0, 0.95);
}

.page-about .about-index__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-index__title {
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--frost);
}

.page-about .about-index__meta {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--mist);
}

.page-about .about-index__list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-index__item {
  border-bottom: 1px dashed var(--line-soft);
}

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

.page-about .about-index__link {
  display: grid;
  grid-template-columns: 62px minmax(0, 1fr) 12px;
  gap: 10px;
  align-items: baseline;
  padding: 12px 4px;
  min-height: 44px;
  color: inherit;
  text-decoration: none;
  transition: background var(--ease) 180ms, color var(--ease) 180ms;
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  background: rgba(92, 255, 177, 0.09);
}

.page-about .about-index__link:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 2px;
  border-radius: 4px;
}

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

.page-about .about-index__text {
  font-size: 13px;
  line-height: 1.6;
  color: rgba(234, 246, 239, 0.86);
}

.page-about .about-index__arrow {
  font-family: var(--font-mono);
  color: var(--line);
  font-size: 13px;
}

.page-about .about-index__link:hover .about-index__arrow,
.page-about .about-index__link:focus-visible .about-index__arrow {
  color: var(--signal);
}

/* 规模条 */
.page-about .about-stats {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: var(--space-4) 0 0;
  padding: 0;
  list-style: none;
  overflow: hidden;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: var(--line-soft);
}

.page-about .about-stats__item {
  padding: 14px 16px;
  background: rgba(11, 42, 33, 0.92);
}

.page-about .about-stats__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 24px;
  line-height: 1.2;
  color: var(--mint);
  letter-spacing: -0.01em;
}

.page-about .about-stats__plus {
  font-size: 14px;
  color: var(--signal);
}

.page-about .about-stats__label {
  display: block;
  margin-top: 4px;
  font-size: 12px;
  line-height: 1.5;
  color: var(--mist);
}

/* ---------- 通用章节 ---------- */
.page-about .about-section {
  padding: var(--space-5) 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-section .section-head {
  margin-bottom: var(--space-4);
}

.page-about .about-prose p {
  margin: 0 0 14px;
  max-width: 64ch;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(234, 246, 239, 0.82);
}

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

.page-about .about-split {
  display: grid;
  gap: var(--space-4);
}

.page-about .about-figure {
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--ink-800);
}

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

.page-about .about-figure figcaption {
  padding: 10px 14px;
  border-top: 1px solid var(--line-soft);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--mist);
}

/* ---------- 数据使命 ---------- */
.page-about .about-mission {
  display: grid;
  gap: var(--space-4);
}

.page-about .about-audience {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .about-audience__card {
  position: relative;
  padding: 18px 18px 20px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: linear-gradient(160deg, rgba(11, 42, 33, 0.9), rgba(7, 28, 22, 0.75));
  transition: border-color var(--ease) 200ms, transform var(--ease) 200ms;
}

.page-about .about-audience__card:hover {
  border-color: rgba(92, 255, 177, 0.42);
  transform: translateY(-2px);
}

.page-about .about-audience__num {
  display: inline-block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--clay);
}

.page-about .about-audience__title {
  margin: 0 0 8px;
  font-size: 16px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--frost);
}

.page-about .about-audience__text {
  margin: 0;
  font-size: 13px;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 会员 ---------- */
.page-about .about-section--member {
  background: linear-gradient(120deg, rgba(255, 159, 67, 0.08), rgba(7, 28, 22, 0) 62%);
}

.page-about .about-member {
  display: grid;
  gap: var(--space-4);
  padding: var(--space-3);
  border: 1px solid rgba(255, 159, 67, 0.34);
  border-radius: var(--radius);
  background: linear-gradient(150deg, rgba(11, 42, 33, 0.96), rgba(7, 28, 22, 0.9));
}

.page-about .about-member__title {
  margin: 6px 0 12px;
  font-size: clamp(22px, 4.4vw, 30px);
  line-height: 1.3;
  letter-spacing: -0.01em;
  font-weight: 800;
  color: var(--frost);
}

.page-about .about-member__text {
  margin: 0 0 var(--space-3);
  max-width: 58ch;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(234, 246, 239, 0.82);
}

.page-about .about-tiers {
  display: grid;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-tiers__item {
  display: grid;
  gap: 4px;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(7, 28, 22, 0.7);
}

.page-about .about-tiers__item--focus {
  border-color: rgba(255, 159, 67, 0.55);
  background: rgba(255, 159, 67, 0.1);
}

.page-about .about-tiers__name {
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.08em;
  color: var(--amber);
}

.page-about .about-tiers__desc {
  font-size: 13px;
  line-height: 1.6;
  color: var(--mist);
}

/* ---------- 内容体系（浅底） ---------- */
.page-about .about-section--sand {
  background: var(--sand);
  color: var(--ink-900);
  border-top: 1px solid rgba(7, 28, 22, 0.2);
}

.page-about .about-section--sand .section-head__title {
  color: var(--ink-900);
}

.page-about .about-section--sand .section-head__index,
.page-about .about-section--sand .section-head__note {
  color: rgba(7, 28, 22, 0.68);
}

.page-about .filing {
  position: relative;
}

.page-about .filing__input {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  border: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
}

.page-about .filing__tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: var(--space-3);
}

.page-about .filing__tab {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 44px;
  padding: 10px 16px;
  border: 1px solid rgba(7, 28, 22, 0.26);
  border-radius: 999px;
  font-size: 14px;
  font-weight: 700;
  color: var(--ink-900);
  cursor: pointer;
  transition: background var(--ease) 200ms, color var(--ease) 200ms, border-color var(--ease) 200ms;
}

.page-about .filing__num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: rgba(7, 28, 22, 0.55);
}

.page-about .filing__tab:hover {
  background: rgba(7, 28, 22, 0.08);
}

.page-about .filing__input:nth-of-type(1):checked ~ .filing__tabs .filing__tab:nth-child(1),
.page-about .filing__input:nth-of-type(2):checked ~ .filing__tabs .filing__tab:nth-child(2),
.page-about .filing__input:nth-of-type(3):checked ~ .filing__tabs .filing__tab:nth-child(3),
.page-about .filing__input:nth-of-type(4):checked ~ .filing__tabs .filing__tab:nth-child(4) {
  background: var(--ink-900);
  border-color: var(--ink-900);
  color: var(--sand);
}

.page-about .filing__input:nth-of-type(1):checked ~ .filing__tabs .filing__tab:nth-child(1) .filing__num,
.page-about .filing__input:nth-of-type(2):checked ~ .filing__tabs .filing__tab:nth-child(2) .filing__num,
.page-about .filing__input:nth-of-type(3):checked ~ .filing__tabs .filing__tab:nth-child(3) .filing__num,
.page-about .filing__input:nth-of-type(4):checked ~ .filing__tabs .filing__tab:nth-child(4) .filing__num {
  color: var(--mint);
}

.page-about .filing__input:nth-of-type(1):focus-visible ~ .filing__tabs .filing__tab:nth-child(1),
.page-about .filing__input:nth-of-type(2):focus-visible ~ .filing__tabs .filing__tab:nth-child(2),
.page-about .filing__input:nth-of-type(3):focus-visible ~ .filing__tabs .filing__tab:nth-child(3),
.page-about .filing__input:nth-of-type(4):focus-visible ~ .filing__tabs .filing__tab:nth-child(4) {
  outline: 2px solid var(--ink-900);
  outline-offset: 2px;
}

.page-about .filing__panel {
  display: none;
  padding: 20px;
  border: 1px solid rgba(7, 28, 22, 0.22);
  border-left: 3px solid var(--clay);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.28);
}

.page-about .filing__input:nth-of-type(1):checked ~ .filing__panels .filing__panel:nth-child(1),
.page-about .filing__input:nth-of-type(2):checked ~ .filing__panels .filing__panel:nth-child(2),
.page-about .filing__input:nth-of-type(3):checked ~ .filing__panels .filing__panel:nth-child(3),
.page-about .filing__input:nth-of-type(4):checked ~ .filing__panels .filing__panel:nth-child(4) {
  display: block;
}

.page-about .filing__title {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 700;
  color: var(--ink-900);
}

.page-about .filing__text {
  margin: 0;
  max-width: 62ch;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(7, 28, 22, 0.82);
}

.page-about .filing__text a {
  color: var(--ink-900);
  font-weight: 700;
  text-decoration: underline;
  text-decoration-color: rgba(7, 28, 22, 0.4);
  text-underline-offset: 3px;
}

.page-about .filing__text a:hover,
.page-about .filing__text a:focus-visible {
  background: var(--mint);
  text-decoration-color: transparent;
}

.page-about .about-team {
  display: grid;
  gap: var(--space-4);
  margin-top: var(--space-4);
}

.page-about .about-team__figure {
  border-color: rgba(7, 28, 22, 0.24);
  background: rgba(7, 28, 22, 0.9);
}

.page-about .about-team__figure figcaption {
  border-top-color: rgba(217, 201, 163, 0.22);
  color: var(--sand);
}

.page-about .about-team__prose p {
  color: rgba(7, 28, 22, 0.82);
}

/* ---------- 时间线 ---------- */
.page-about .timeline {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 28px;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg, var(--mint) 0%, var(--line) 62%, rgba(29, 74, 58, 0) 100%);
}

.page-about .timeline__item {
  position: relative;
  padding-bottom: var(--space-3);
}

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

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -24px;
  top: 16px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  border: 1px solid var(--mint);
  background: var(--ink-900);
  transition: background var(--ease) 200ms, box-shadow var(--ease) 200ms;
}

.page-about .timeline__node {
  padding: 16px 18px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: rgba(11, 42, 33, 0.62);
  outline: none;
  transition: border-color var(--ease) 200ms, background var(--ease) 200ms, transform var(--ease) 200ms;
}

.page-about .timeline__node:hover,
.page-about .timeline__node:focus-visible {
  border-color: rgba(92, 255, 177, 0.5);
  background: rgba(92, 255, 177, 0.07);
  transform: translateX(3px);
}

.page-about .timeline__node:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 2px;
}

.page-about .timeline__item:hover::before,
.page-about .timeline__item:focus-within::before {
  background: var(--mint);
  box-shadow: 0 0 0 4px rgba(92, 255, 177, 0.16);
}

.page-about .timeline__year {
  display: inline-block;
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--signal);
}

.page-about .timeline__title {
  margin: 0 0 6px;
  font-size: 16px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--frost);
}

.page-about .timeline__text {
  margin: 0;
  max-width: 66ch;
  font-size: 13px;
  line-height: 1.8;
  color: var(--mist);
  transition: color var(--ease) 200ms;
}

.page-about .timeline__node:hover .timeline__text,
.page-about .timeline__node:focus-visible .timeline__text {
  color: rgba(234, 246, 239, 0.92);
}

/* ---------- 服务承诺 ---------- */
.page-about .about-section--service {
  background: linear-gradient(180deg, rgba(7, 28, 22, 0) 0%, rgba(11, 42, 33, 0.55) 100%);
}

.page-about .about-service {
  display: grid;
  gap: var(--space-4);
}

.page-about .fold {
  margin-bottom: 10px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: rgba(11, 42, 33, 0.55);
  overflow: hidden;
}

.page-about .fold[open] {
  border-color: rgba(92, 255, 177, 0.32);
}

.page-about .fold__summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-height: 44px;
  padding: 14px 16px;
  font-size: 14px;
  font-weight: 700;
  color: var(--frost);
  cursor: pointer;
  list-style: none;
}

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

.page-about .fold__summary:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: -2px;
}

.page-about .fold__icon::before {
  content: "+";
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--mint);
}

.page-about .fold[open] .fold__icon::before {
  content: "−";
}

.page-about .fold__body {
  padding: 0 16px 16px;
  font-size: 13px;
  line-height: 1.85;
  color: rgba(234, 246, 239, 0.78);
}

.page-about .about-contact {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: var(--space-3) 0 0;
  padding: 0;
  list-style: none;
  overflow: hidden;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: var(--line-soft);
}

.page-about .about-contact__item {
  display: grid;
  gap: 3px;
  padding: 12px 16px;
  background: rgba(7, 28, 22, 0.86);
}

.page-about .about-contact__key {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--clay);
}

.page-about .about-contact__value {
  font-size: 13px;
  line-height: 1.6;
  color: var(--frost);
  word-break: break-word;
}

.page-about .about-contact__note {
  margin: 12px 0 0;
  font-size: 12px;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .about-service__aside {
  display: grid;
  gap: var(--space-3);
  align-content: start;
}

.page-about .about-service__links {
  display: grid;
  gap: 10px;
}

/* ---------- 媒体查询 ---------- */
@media (min-width: 640px) {
  .page-about .about-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: var(--space-5) 0 var(--space-6);
  }

  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: var(--space-5);
    align-items: start;
  }

  .page-about .about-section {
    padding: var(--space-6) 0;
  }

  .page-about .about-split {
    grid-template-columns: minmax(0, 6fr) minmax(0, 6fr);
    gap: var(--space-5);
    align-items: start;
  }

  .page-about .about-mission {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: var(--space-5);
    align-items: start;
  }

  .page-about .about-member {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: var(--space-5);
    padding: var(--space-4);
    align-items: center;
  }

  .page-about .about-team {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: var(--space-5);
    align-items: start;
  }

  .page-about .about-service {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: var(--space-5);
    align-items: start;
  }

  .page-about .timeline {
    padding-left: 34px;
  }

  .page-about .timeline::before {
    left: 12px;
  }

  .page-about .timeline__item::before {
    left: -27px;
  }
}

@media (min-width: 1080px) {
  .page-about .about-stats {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }

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

  .page-about .about-tiers {
    gap: 12px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-audience__card,
  .page-about .timeline__node,
  .page-about .filing__tab,
  .page-about .about-index__link {
    transition: none;
  }

  .page-about .about-audience__card:hover,
  .page-about .timeline__node:hover,
  .page-about .timeline__node:focus-visible {
    transform: none;
  }
}
<<<END>>>