.page-about {
  --about-rail-w: 190px;
  --about-soft: rgba(35, 58, 52, 0.62);
  background: var(--ink);
  color: var(--white);
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  padding: calc(var(--header-h) + clamp(20px, 5vw, 52px)) 0 clamp(52px, 9vw, 104px);
  background:
    radial-gradient(120% 90% at 88% -12%, rgba(61, 242, 196, 0.18), transparent 55%),
    radial-gradient(90% 80% at 0% 112%, rgba(140, 91, 255, 0.16), transparent 62%),
    linear-gradient(155deg, var(--ink-2), var(--ink) 72%);
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(to right, var(--line-soft) 1px, transparent 1px),
    linear-gradient(to bottom, var(--line-soft) 1px, transparent 1px);
  background-size: 64px 64px;
  -webkit-mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.9), transparent 78%);
  mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.9), transparent 78%);
}

.page-about .about-hero .breadcrumb {
  margin-bottom: clamp(24px, 4vw, 44px);
}

.page-about .about-hero .breadcrumb a {
  color: var(--mist);
}

.page-about .about-hero .index-label {
  color: var(--cyan);
  margin: 0;
}

.page-about .hero-grid {
  display: grid;
  gap: clamp(28px, 5vw, 48px);
}

.page-about .hero-title {
  margin: 16px 0 0;
  font-size: clamp(40px, 10vw, 112px);
  font-weight: 200;
  line-height: 0.98;
  letter-spacing: -0.04em;
}

.page-about .hero-l1,
.page-about .hero-l2 {
  display: block;
}

.page-about .hero-l2 {
  margin-top: 0.1em;
  font-size: 0.62em;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-about .hero-l2 .display-accent {
  font-style: italic;
  font-weight: 900;
  color: var(--cyan);
}

.page-about .hero-lede {
  max-width: 52ch;
  margin: 24px 0 0;
  font-size: clamp(15px, 1.7vw, 17px);
  line-height: 1.85;
  color: var(--mist);
}

.page-about .hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.page-about .hero-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 18px 42px;
  margin: 34px 0 0;
  padding-top: 22px;
  border-top: 1px solid var(--line);
}

.page-about .hero-facts dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .hero-facts dd {
  margin: 8px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(20px, 3vw, 28px);
  color: var(--cyan);
}

.page-about .hero-figure {
  position: relative;
  margin: 0;
  clip-path: polygon(0 4%, 100% 0, 100% 96%, 0 100%);
}

.page-about .hero-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 5;
  object-fit: cover;
  filter: saturate(0.9) contrast(1.06);
}

.page-about .hero-figure figcaption {
  position: absolute;
  left: 16px;
  bottom: 20px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cyan);
}

@media (min-width: 900px) {
  .page-about .hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: end;
    gap: clamp(32px, 4vw, 64px);
  }
}

/* ---------- 主体区 ---------- */
.page-about .about-body {
  background: var(--paper);
  color: var(--graphite);
  padding: clamp(36px, 6vw, 84px) 0 clamp(56px, 8vw, 108px);
}

.page-about .about-layout {
  display: block;
}

.page-about .about-rail {
  display: none;
}

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

@media (min-width: 1000px) {
  .page-about .about-layout {
    display: grid;
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: clamp(32px, 4vw, 72px);
    align-items: start;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: calc(var(--header-h) + 28px);
  }
}

.page-about .rail-title {
  margin: 0 0 14px;
  color: var(--about-soft);
}

.page-about .rail-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-left: 1px solid var(--line-paper);
}

.page-about .rail-list a {
  display: flex;
  gap: 10px;
  align-items: baseline;
  margin-left: -1px;
  padding: 8px 0 8px 14px;
  border-left: 2px solid transparent;
  font-size: 14px;
  color: var(--graphite);
  text-decoration: none;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .rail-list a span {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--about-soft);
}

.page-about .rail-list a:hover,
.page-about .rail-list a:focus-visible {
  color: var(--ink-2);
  border-left-color: var(--ink-2);
}

/* ---------- 章节 ---------- */
.page-about .about-section {
  padding: clamp(28px, 5vw, 52px) 0;
  border-top: 1px solid var(--line-paper);
}

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

.page-about .index-label {
  margin: 0;
  color: var(--about-soft);
}

.page-about .about-h2 {
  margin: 10px 0 22px;
  font-size: clamp(25px, 4.2vw, 44px);
  font-weight: 200;
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--ink-2);
}

.page-about .section-lede {
  max-width: 62ch;
  margin: 0 0 26px;
  font-size: clamp(15px, 1.7vw, 17px);
  line-height: 1.85;
}

.page-about .prose p {
  max-width: 66ch;
  margin: 0 0 18px;
  font-size: clamp(15px, 1.6vw, 16.5px);
  line-height: 1.85;
}

.page-about .prose a,
.page-about .partner-foot a {
  color: var(--ink-2);
  text-decoration: none;
  border-bottom: 1px solid var(--orange);
  padding-bottom: 1px;
}

.page-about .prose a:hover,
.page-about .partner-foot a:hover {
  color: var(--orange);
}

.page-about .stance-grid {
  align-items: start;
  gap: clamp(24px, 4vw, 44px);
}

.page-about .stance-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .stance-list li {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding-top: 14px;
  border-top: 1px solid var(--line-paper);
}

.page-about .stance-num {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border: 1px solid var(--line-paper);
  font-family: var(--font-mono);
  font-size: 20px;
  color: var(--ink-2);
}

.page-about .stance-list p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--graphite);
}

/* ---------- 会员权益 ---------- */
.page-about .tier-grid {
  display: grid;
  gap: 16px;
  margin: 4px 0 26px;
}

.page-about .tier {
  border: 1px solid var(--line-paper);
  border-top: 3px solid var(--ink-2);
  background: rgba(255, 255, 255, 0.46);
  padding: 20px 18px 22px;
}

.page-about .tier--1 {
  border-top-color: var(--ink-2);
}

.page-about .tier--2 {
  border-top-color: var(--violet);
}

.page-about .tier--3 {
  border-top-color: var(--orange);
}

.page-about .tier-tag {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--about-soft);
}

.page-about .tier-name {
  margin: 0 0 10px;
  font-size: 18px;
  font-weight: 500;
  line-height: 1.45;
  color: var(--ink-2);
}

.page-about .tier-text {
  margin: 0 0 14px;
  font-size: 14px;
  line-height: 1.8;
}

.page-about .tier-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 7px;
}

.page-about .tier-list li {
  position: relative;
  padding-left: 16px;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--about-soft);
}

.page-about .tier-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 7px;
  height: 1px;
  background: var(--ink-2);
}

@media (min-width: 820px) {
  .page-about .tier-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
    align-items: start;
  }

  .page-about .tier--2 {
    margin-top: 24px;
  }

  .page-about .tier--3 {
    margin-top: 48px;
  }
}

.page-about .tier-details {
  border-top: 1px solid var(--line-paper);
  margin-bottom: 6px;
}

.page-about .tier-details .accordion__summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 15px 0;
  border-bottom: 1px solid var(--line-paper);
  font-size: 15px;
  font-weight: 500;
  color: var(--ink-2);
  cursor: pointer;
  list-style: none;
}

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

.page-about .tier-details .accordion__summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--orange);
}

.page-about .tier-details .accordion__item[open] .accordion__summary::after {
  content: "–";
}

.page-about .tier-details .accordion__body {
  padding: 14px 0 18px;
  border-bottom: 1px solid var(--line-paper);
}

.page-about .tier-details .accordion__body p {
  max-width: 66ch;
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
}

.page-about .member-figure {
  margin: 26px 0 0;
}

.page-about .member-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border: 1px solid var(--line-paper);
}

.page-about .member-figure figcaption,
.page-about .team-figure figcaption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--about-soft);
}

/* ---------- 深色段落 ---------- */
.page-about .about-section--ink,
.page-about .about-section--ink2 {
  margin: clamp(18px, 3vw, 32px) 0;
  padding: clamp(26px, 4vw, 44px) clamp(18px, 3.4vw, 40px);
  background: var(--ink-2);
  color: var(--white);
  border-top: 0;
}

.page-about .about-section--ink2 {
  background: linear-gradient(150deg, var(--ink), var(--ink-2) 78%);
}

.page-about .about-section--ink .index-label,
.page-about .about-section--ink2 .index-label {
  color: var(--cyan);
}

.page-about .about-section--ink .about-h2,
.page-about .about-section--ink2 .about-h2 {
  color: var(--white);
}

.page-about .about-section--ink .section-lede,
.page-about .about-section--ink2 .section-lede {
  color: var(--mist);
}

.page-about .era-axis {
  display: block;
  width: 100%;
  max-width: 620px;
  height: auto;
  margin: 0 0 22px;
}

.page-about .tab-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 22px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line);
}

.page-about .tab {
  appearance: none;
  background: transparent;
  border: 1px solid var(--line);
  padding: 9px 13px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist);
  cursor: pointer;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .tab:hover,
.page-about .tab:focus-visible {
  border-color: var(--cyan);
  color: var(--white);
}

.page-about .tab[aria-selected="true"] {
  background: var(--cyan);
  border-color: var(--cyan);
  color: var(--ink);
  font-weight: 700;
}

.page-about .tab-panel {
  color: var(--mist);
}

.page-about .tab-panel p {
  max-width: 68ch;
  margin: 0 0 14px;
  font-size: clamp(14.5px, 1.6vw, 16px);
  line-height: 1.85;
}

/* ---------- 数据统计 ---------- */
.page-about .data-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 26px;
}

.page-about .data-stat {
  border: 1px solid var(--line-paper);
  border-left: 3px solid var(--violet);
  padding: 14px 14px 16px;
}

.page-about .data-stat:nth-child(2) {
  border-left-color: var(--orange);
}

.page-about .data-stat:nth-child(3) {
  border-left-color: var(--ink-2);
}

.page-about .data-stat:nth-child(4) {
  border-left-color: var(--violet);
}

.page-about .data-stat .stat__value {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(20px, 2.8vw, 27px);
  line-height: 1.2;
  color: var(--ink-2);
}

.page-about .data-stat .stat__label {
  display: block;
  margin-top: 8px;
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: var(--about-soft);
}

@media (min-width: 720px) {
  .page-about .data-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  align-items: start;
  gap: clamp(24px, 4vw, 40px);
}

.page-about .team-grid .prose p {
  color: var(--mist);
}

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

.page-about .team-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 14 / 9;
  object-fit: cover;
  border: 1px solid var(--line);
  clip-path: polygon(0 3%, 100% 0, 100% 100%, 0 97%);
}

.page-about .team-figure figcaption {
  color: var(--mist);
}

.page-about .team-roster {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin: 24px 0 0;
  padding: 0;
}

.page-about .team-roster li {
  border-top: 1px solid var(--line);
  padding-top: 12px;
}

.page-about .roster-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(22px, 3vw, 32px);
  color: var(--cyan);
  line-height: 1.1;
}

.page-about .roster-label {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist);
}

@media (min-width: 720px) {
  .page-about .team-roster {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 合作 ---------- */
.page-about .partner-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .partner-list li {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  padding: 16px 0;
  border-top: 1px solid var(--line-paper);
}

.page-about .partner-num {
  font-family: var(--font-mono);
  font-size: clamp(20px, 3vw, 26px);
  color: var(--ink-2);
  line-height: 1.2;
}

.page-about .partner-text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--graphite);
}

.page-about .partner-foot {
  margin: 20px 0 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--about-soft);
}

@media (min-width: 720px) {
  .page-about .partner-list li {
    grid-template-columns: 120px minmax(0, 1fr);
    gap: 26px;
    padding: 20px 0;
  }
}

/* ---------- 开始使用 ---------- */
.page-about .join-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 4px 0 28px;
}

.page-about .join-contact {
  display: grid;
  gap: 12px;
}

.page-about .join-contact .contact-item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  border: 1px solid var(--line);
  padding: 14px 16px;
}

.page-about .join-contact .contact-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .join-contact .contact-value {
  font-size: 14px;
  line-height: 1.7;
  color: var(--white);
  word-break: break-word;
}

.page-about .copy-btn {
  align-self: flex-start;
  margin-top: 6px;
  padding: 7px 13px;
  background: transparent;
  border: 1px solid var(--cyan);
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  cursor: pointer;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .copy-btn:hover,
.page-about .copy-btn:focus-visible {
  background: rgba(61, 242, 196, 0.14);
}

.page-about .copy-btn.is-copied {
  background: var(--cyan);
  color: var(--ink);
  border-color: var(--cyan);
}

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

/* ---------- 窄屏兜底 ---------- */
@media (max-width: 480px) {
  .page-about .hero-facts {
    gap: 14px 26px;
  }

  .page-about .tier {
    padding: 18px 15px 20px;
  }

  .page-about .partner-list li {
    grid-template-columns: 60px minmax(0, 1fr);
    gap: 12px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tab,
  .page-about .copy-btn,
  .page-about .rail-list a {
    transition: none;
  }
}
<<<PAGE_CSS_END>>>