.page-about {
  --rail-w: 232px;
  --about-gap: 56px;
  --rail-top: 108px;
  padding-bottom: 88px;
  overflow-x: hidden;
}

/* ---------- 封面 ---------- */
.page-about .about-cover {
  position: relative;
  background: var(--mint-glow);
  border-bottom: 1px solid var(--hairline);
  padding: 40px 0 56px;
  overflow: hidden;
}

.page-about .about-cover::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    repeating-linear-gradient(90deg, rgba(42, 59, 52, 0.5) 0 1px, transparent 1px 76px),
    repeating-linear-gradient(0deg, rgba(42, 59, 52, 0.5) 0 1px, transparent 1px 76px);
  -webkit-mask-image: radial-gradient(120% 100% at 80% 0%, #000 0%, transparent 72%);
  mask-image: radial-gradient(120% 100% at 80% 0%, #000 0%, transparent 72%);
  pointer-events: none;
}

.page-about .about-cover__inner {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: 36px;
}

.page-about .about-eyebrow {
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--cyan);
  margin: 0 0 18px;
}

.page-about .about-cover__title {
  margin: 0 0 20px;
  font-size: clamp(32px, 7.2vw, 52px);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.08;
  color: var(--text);
}

.page-about .about-cover__lede {
  margin: 0 0 28px;
  max-width: 60ch;
  font-size: var(--fs-16);
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-cover__stats {
  list-style: none;
  margin: 0 0 32px;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 12px 32px;
}

.page-about .about-cover__stats li {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding-left: 14px;
  border-left: 2px solid var(--cyan);
}

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

.page-about .about-cover__stats li:nth-child(3) {
  border-left-color: var(--amber);
}

.page-about .stat-value {
  font-size: var(--fs-28);
  font-weight: 700;
  color: var(--text);
  line-height: 1.1;
}

.page-about .stat-label {
  font-size: var(--fs-12);
  color: var(--muted);
  letter-spacing: 0.04em;
}

.page-about .about-cover__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-cover__media {
  margin: 0;
  position: relative;
  border: 1px solid var(--hairline);
  background: var(--panel-deep);
  box-shadow: var(--shadow-panel);
}

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

.page-about .media-caption {
  display: block;
  padding: 10px 14px;
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  color: var(--muted);
  border-top: 1px solid var(--hairline);
}

/* ---------- 章节骨架 ---------- */
.page-about .chapter-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 34px;
  padding-top: 56px;
}

.page-about .chapter-rail {
  border-top: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
  padding: 14px 0;
}

.page-about .rail-label {
  margin: 0 0 10px;
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .rail-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 20px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .rail-list li {
  flex: 0 0 auto;
}

.page-about .rail-link {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 6px 0;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur) var(--ease);
}

.page-about .rail-num {
  font-size: var(--fs-12);
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.page-about .rail-text {
  font-size: var(--fs-14);
  color: var(--muted);
  white-space: nowrap;
  transition: color var(--dur) var(--ease);
}

.page-about .rail-link:hover .rail-text,
.page-about .rail-link:focus-visible .rail-text {
  color: var(--text);
}

.page-about .rail-link:hover {
  border-bottom-color: var(--cyan);
}

.page-about .chapter {
  padding-top: 36px;
  border-top: 1px solid var(--hairline);
  margin-bottom: 64px;
}

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

.page-about .chapter-head {
  display: grid;
  gap: 10px;
  margin-bottom: 26px;
}

.page-about .chapter-num {
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .chapter-title {
  margin: 0;
  font-size: clamp(23px, 4.6vw, 30px);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.28;
  color: var(--text);
}

.page-about .chapter-kicker {
  margin: 0;
  font-size: var(--fs-14);
  color: var(--amber);
  letter-spacing: 0.02em;
}

.page-about .chapter-body > p {
  margin: 0 0 18px;
  max-width: 64ch;
  font-size: var(--fs-16);
  line-height: 1.85;
  color: var(--muted);
}

.page-about .chapter-note {
  margin-top: 26px;
  padding: 20px 22px;
  background: var(--panel-deep);
  border: 1px solid var(--hairline);
  border-left: 2px solid var(--cyan);
}

.page-about .chapter-note p {
  margin: 0;
  max-width: 62ch;
  font-size: var(--fs-16);
  line-height: 1.85;
  color: var(--text);
}

/* ---------- 使用场景 ---------- */
.page-about .scene-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
  margin-top: 8px;
}

.page-about .about-card {
  position: relative;
  padding: 22px 22px 24px;
  background: var(--panel-deep);
  border: 1px solid var(--hairline);
  border-top-width: 2px;
  box-shadow: var(--shadow-panel);
  transition: transform var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .about-card:hover {
  transform: translateY(-2px);
  background: var(--panel);
}

.page-about .about-card--cyan { border-top-color: var(--cyan); }
.page-about .about-card--orange { border-top-color: var(--orange); }
.page-about .about-card--amber { border-top-color: var(--amber); }
.page-about .about-card--mist { border-top-color: var(--mist); }

.page-about .about-card__title {
  margin: 0 0 10px;
  font-size: var(--fs-18);
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.01em;
}

.page-about .about-card__text {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 团队构成 ---------- */
.page-about .team-visual {
  margin-top: 12px;
}

.page-about .team-bar {
  display: flex;
  height: 16px;
  margin-bottom: 26px;
  background: var(--panel-deep);
  border: 1px solid var(--hairline);
}

.page-about .team-bar__seg {
  height: 100%;
  transition: opacity var(--dur) var(--ease);
}

.page-about .team-bar__seg:nth-child(1) { width: 35.3%; background: var(--cyan); }
.page-about .team-bar__seg:nth-child(2) { width: 23.5%; background: var(--mist); }
.page-about .team-bar__seg:nth-child(3) { width: 32.4%; background: var(--orange); }
.page-about .team-bar__seg:nth-child(4) { width: 8.8%; background: var(--amber); }

.page-about .team-bar:hover .team-bar__seg {
  opacity: 0.55;
}

.page-about .team-bar__seg:hover {
  opacity: 1;
}

.page-about .team-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.page-about .team-item {
  display: grid;
  grid-template-columns: 10px auto auto;
  align-items: center;
  gap: 10px;
  padding: 16px 18px;
  background: var(--panel-deep);
  border: 1px solid var(--hairline);
}

.page-about .team-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.page-about .team-item--cyan .team-dot { background: var(--cyan); }
.page-about .team-item--mist .team-dot { background: var(--mist); }
.page-about .team-item--orange .team-dot { background: var(--orange); }
.page-about .team-item--amber .team-dot { background: var(--amber); }

.page-about .team-name {
  font-size: var(--fs-16);
  font-weight: 700;
  color: var(--text);
}

.page-about .team-count {
  font-size: var(--fs-14);
  color: var(--cyan);
  margin-left: auto;
}

.page-about .team-duty {
  grid-column: 2 / -1;
  margin: 4px 0 0;
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 发布链路 ---------- */
.page-about .flow-steps {
  list-style: none;
  margin: 10px 0 0;
  padding: 0;
}

.page-about .flow-step {
  position: relative;
  padding: 0 0 28px 26px;
  border-left: 1px solid var(--hairline);
}

.page-about .flow-step:last-child {
  padding-bottom: 4px;
}

.page-about .flow-step::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 6px;
  width: 7px;
  height: 7px;
  background: var(--cyan);
}

.page-about .flow-num {
  display: block;
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--cyan);
  margin-bottom: 6px;
}

.page-about .flow-title {
  margin: 0 0 8px;
  font-size: var(--fs-18);
  font-weight: 700;
  color: var(--text);
}

.page-about .flow-text {
  margin: 0;
  max-width: 62ch;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-figure {
  margin: 30px 0 0;
  border: 1px solid var(--hairline);
  background: var(--panel-deep);
}

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

.page-about .about-figure--trail {
  margin-top: 34px;
}

/* ---------- 版本切换 ---------- */
.page-about .version-tabs {
  margin-top: 8px;
}

.page-about .tab-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  border-bottom: 1px solid var(--hairline);
  padding-bottom: 12px;
}

.page-about .tab {
  appearance: none;
  cursor: pointer;
  padding: 10px 16px;
  font-family: var(--font-sans);
  font-size: var(--fs-14);
  font-weight: 700;
  color: var(--muted);
  background: var(--panel-deep);
  border: 1px solid var(--hairline);
  border-radius: var(--radius);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .tab:hover {
  color: var(--text);
  border-color: var(--cyan);
}

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

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

.page-about .tab-status {
  margin: 12px 0 0;
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  color: var(--amber);
}

.page-about .tab-panel {
  margin-top: 20px;
  padding: 22px 22px 24px;
  background: var(--panel-deep);
  border: 1px solid var(--hairline);
  border-left: 2px solid var(--cyan);
}

.page-about .panel-heading {
  margin: 0 0 12px;
  font-size: var(--fs-18);
  font-weight: 700;
  color: var(--text);
}

.page-about .tab-panel p {
  margin: 0 0 14px;
  max-width: 62ch;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--muted);
}

.page-about .panel-result {
  margin: 0;
  padding-top: 12px;
  border-top: 1px solid var(--hairline);
  color: var(--text);
}

.page-about .panel-result .num {
  display: inline-block;
  margin-right: 8px;
  font-size: var(--fs-12);
  letter-spacing: 0.14em;
  color: var(--orange);
}

/* ---------- 品质标准 ---------- */
.page-about .standard-list {
  list-style: none;
  margin: 8px 0 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .standard-item {
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 16px;
  padding: 20px;
  background: var(--panel-deep);
  border: 1px solid var(--hairline);
}

.page-about .standard-num {
  font-size: var(--fs-22);
  font-weight: 700;
  color: var(--cyan);
  line-height: 1.2;
}

.page-about .standard-title {
  margin: 0 0 8px;
  font-size: var(--fs-16);
  font-weight: 700;
  color: var(--text);
}

.page-about .standard-item p {
  margin: 0;
  max-width: 62ch;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 后续入口 ---------- */
.page-about .chapter--closing {
  margin-bottom: 0;
}

.page-about .next-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin-top: 8px;
}

.page-about .next-card {
  display: grid;
  gap: 8px;
  padding: 20px;
  text-decoration: none;
  background: var(--panel-deep);
  border: 1px solid var(--hairline);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .next-card:hover {
  border-color: var(--cyan);
  transform: translateY(-2px);
}

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

.page-about .next-num {
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .next-title {
  font-size: var(--fs-18);
  font-weight: 700;
  color: var(--text);
}

.page-about .next-text {
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--muted);
}

.page-about .next-go {
  font-size: var(--fs-12);
  letter-spacing: 0.12em;
  color: var(--orange);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .scene-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

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

@media (min-width: 900px) {
  .page-about .about-cover {
    padding: 64px 0 76px;
  }

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

  .page-about .standard-item {
    grid-template-columns: 64px 1fr;
    padding: 24px;
  }
}

@media (min-width: 1024px) {
  .page-about .chapter-layout {
    grid-template-columns: var(--rail-w) minmax(0, 1fr);
    gap: var(--about-gap);
    padding-top: 72px;
  }

  .page-about .chapter-rail {
    position: sticky;
    top: var(--rail-top);
    align-self: start;
    border-top: 0;
    border-bottom: 0;
    padding: 0;
  }

  .page-about .rail-label {
    padding-bottom: 12px;
    border-bottom: 1px solid var(--hairline);
  }

  .page-about .rail-list {
    display: block;
    overflow: visible;
    padding-top: 6px;
  }

  .page-about .rail-list li {
    border-bottom: 1px solid var(--hairline);
  }

  .page-about .rail-link {
    padding: 11px 0 11px 2px;
    border-bottom: 0;
  }

  .page-about .rail-text {
    white-space: normal;
  }

  .page-about .chapter {
    padding-top: 40px;
    margin-bottom: 76px;
  }

  .page-about .flow-steps {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0 32px;
  }

  .page-about .flow-step {
    padding-bottom: 26px;
  }

  .page-about .flow-step:nth-child(3) {
    padding-bottom: 4px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-card,
  .page-about .next-card,
  .page-about .team-bar__seg,
  .page-about .tab,
  .page-about .rail-text,
  .page-about .rail-link {
    transition: none;
  }

  .page-about .about-card:hover,
  .page-about .next-card:hover {
    transform: none;
  }
}
<<<END>>>