.page-about {
  --about-rail: 232px;
  --about-gap: clamp(24px, 4.5vw, 68px);
  --about-panel: var(--ink-100);
  background: var(--ink-000);
  color: var(--mist);
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(126deg, var(--ink-100) 0%, var(--ink-100) 54%, var(--ink-000) 54.2%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(to right, rgba(38, 52, 77, 0.55) 0 1px, transparent 1px 72px),
    repeating-linear-gradient(to bottom, rgba(38, 52, 77, 0.55) 0 1px, transparent 1px 72px);
  opacity: 0.6;
}

.page-about .about-hero__grid {
  position: relative;
  display: grid;
  gap: clamp(28px, 5vw, 58px);
  padding-block: clamp(32px, 5.5vw, 84px);
  align-items: center;
}

.page-about .about-hero__crumb {
  margin-bottom: 22px;
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-family: var(--font-head);
  font-size: clamp(30px, 6vw, 62px);
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.02em;
  color: var(--white);
  max-width: 15em;
}

.page-about .about-hero__lede {
  margin: 18px 0 0;
  max-width: 46ch;
  font-size: clamp(15px, 2.2vw, 17px);
  line-height: 1.78;
  color: var(--mist);
}

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

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 32px 0 0;
  border: 1px solid var(--line);
  background: var(--line);
}

.page-about .about-stat {
  background: var(--ink-100);
  padding: 14px 16px 16px;
}

.page-about .about-stat__label {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist);
  line-height: 1.5;
}

.page-about .about-stat__num {
  margin: 8px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(20px, 4vw, 26px);
  line-height: 1.1;
  color: var(--amber);
}

.page-about .about-hero__figure {
  position: relative;
  margin: 0;
  border: 1px solid var(--line);
  background: var(--ink-200);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 40px), calc(100% - 40px) 100%, 0 100%);
}

.page-about .about-hero__figure::after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 64px;
  height: 3px;
  background: var(--cyan);
}

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

/* ---------- 非对称长卷骨架 ---------- */
.page-about .about-layout {
  display: grid;
  gap: var(--about-gap);
  padding-block: clamp(36px, 5.5vw, 76px);
}

.page-about .about-rail {
  border-top: 1px solid var(--line);
  padding-top: 16px;
}

.page-about .about-rail__label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--cyan);
  margin: 0 0 14px;
}

.page-about .about-rail__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}

.page-about .about-rail__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-rail__list .index-item {
  flex: 0 0 auto;
}

.page-about .about-rail__list .index-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid var(--line);
  font-size: 13px;
  line-height: 1.4;
  color: var(--mist);
  text-decoration: none;
  white-space: nowrap;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-rail__list .index-num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--cyan);
}

.page-about .about-rail__list .index-link:hover,
.page-about .about-rail__list .index-link:focus-visible {
  color: var(--white);
  border-color: var(--cyan);
  outline: none;
}

.page-about .about-rail__list .index-link[aria-current] {
  color: var(--white);
  border-color: var(--cyan);
  background: rgba(45, 226, 230, 0.09);
}

.page-about .about-rail__note {
  margin: 18px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--mist);
  max-width: 30ch;
}

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

.page-about .about-chapter {
  padding-block: clamp(26px, 4.5vw, 52px);
  border-top: 1px solid var(--line);
}

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

.page-about .about-chapter__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--amber);
}

.page-about .about-chapter__title {
  margin: 12px 0 0;
  font-family: var(--font-head);
  font-size: clamp(23px, 3.4vw, 38px);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.015em;
  color: var(--white);
  max-width: 20em;
}

.page-about .about-chapter__text {
  margin: 16px 0 0;
  max-width: 62ch;
  font-size: clamp(15px, 2vw, 16px);
  line-height: 1.8;
}

.page-about .about-chapter__points {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
  max-width: 62ch;
}

.page-about .about-chapter__points li {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  font-size: 15px;
  line-height: 1.7;
  padding-bottom: 12px;
  border-bottom: 1px dashed var(--line);
}

.page-about .about-chapter__dot {
  flex: 0 0 auto;
  width: 7px;
  height: 7px;
  margin-top: 9px;
  background: var(--cyan);
  transform: rotate(45deg);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  position: relative;
  margin: clamp(24px, 4vw, 40px) 0 0;
  padding: 0 0 0 22px;
  list-style: none;
  border-left: 1px solid var(--line);
}

.page-about .about-milestone {
  position: relative;
  margin-bottom: 14px;
  padding: 16px 18px 18px;
  background: var(--ink-100);
  border: 1px solid var(--line);
  border-left: 2px solid var(--line);
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .about-milestone::before {
  content: "";
  position: absolute;
  left: -27px;
  top: 22px;
  width: 9px;
  height: 9px;
  background: var(--ink-000);
  border: 1px solid var(--amber);
  transform: rotate(45deg);
}

.page-about .about-milestone:hover,
.page-about .about-milestone:focus-within {
  border-left-color: var(--cyan);
  background: var(--ink-200);
  transform: translateX(3px);
}

.page-about .about-milestone--key {
  border-left-color: var(--amber);
}

.page-about .about-milestone__tag {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--amber);
}

.page-about .about-milestone__name {
  margin: 8px 0 0;
  font-family: var(--font-head);
  font-size: clamp(17px, 2.4vw, 21px);
  font-weight: 700;
  line-height: 1.3;
  color: var(--white);
}

.page-about .about-milestone__more {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--mist);
  opacity: 0.86;
  transition: opacity var(--dur) var(--ease);
}

.page-about .about-milestone:hover .about-milestone__more,
.page-about .about-milestone:focus-within .about-milestone__more {
  opacity: 1;
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  display: grid;
  gap: 14px;
  margin-top: 26px;
}

.page-about .about-team__card {
  padding: 18px 18px 20px;
  background: var(--ink-100);
  border: 1px solid var(--line);
  border-top: 2px solid var(--teal);
  transition: border-top-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-team__card:hover {
  border-top-color: var(--cyan);
  background: var(--ink-200);
}

.page-about .about-team__no {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .about-team__name {
  margin: 8px 0 0;
  font-family: var(--font-head);
  font-size: 18px;
  font-weight: 700;
  color: var(--white);
}

.page-about .about-team__desc {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .about-team__figure {
  margin: 30px 0 0;
  border: 1px solid var(--line);
  background: var(--ink-200);
}

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

.page-about .about-team__caption {
  padding: 12px 16px;
  font-size: 12.5px;
  line-height: 1.6;
  letter-spacing: 0.02em;
  color: var(--mist);
  border-top: 1px solid var(--line);
}

/* ---------- 原则 ---------- */
.page-about .about-rules {
  display: grid;
  gap: 1px;
  margin-top: 26px;
  border: 1px solid var(--line);
  background: var(--line);
}

.page-about .about-rule {
  background: var(--ink-100);
  padding: 20px 20px 22px;
}

.page-about .about-rule__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--amber);
}

.page-about .about-rule__name {
  margin: 8px 0 0;
  font-family: var(--font-head);
  font-size: 17px;
  font-weight: 700;
  color: var(--white);
}

.page-about .about-rule__text {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 服务对象 ---------- */
.page-about .about-audience {
  display: grid;
  gap: 0;
  margin-top: 26px;
}

.page-about .about-audience__row {
  display: grid;
  gap: 6px;
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-audience__row:first-child {
  border-top: 1px solid var(--line);
}

.page-about .about-audience__idx {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .about-audience__who {
  margin: 0;
  font-family: var(--font-head);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--white);
}

.page-about .about-audience__what {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--mist);
}

/* ---------- 生态 ---------- */
.page-about .about-eco {
  display: grid;
  gap: 24px;
  margin-top: 28px;
}

.page-about .about-eco__figure {
  margin: 0;
  position: relative;
  border: 1px solid var(--line);
  background: var(--ink-200);
  overflow: hidden;
}

.page-about .about-eco__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  opacity: 0.9;
}

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

.page-about .about-eco__quote {
  margin: 0;
  padding-left: 16px;
  border-left: 3px solid var(--cyan);
  font-size: 16px;
  line-height: 1.75;
  color: var(--white);
}

.page-about .about-eco__list {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-eco__list li {
  position: relative;
  padding-left: 18px;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--mist);
}

.page-about .about-eco__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 6px;
  height: 6px;
  background: var(--amber);
  transform: rotate(45deg);
}

.page-about .about-eco__side .btn {
  margin-top: 24px;
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  margin-top: clamp(36px, 5.5vw, 64px);
  padding: clamp(24px, 4vw, 44px);
  border: 1px solid var(--line);
  background: linear-gradient(132deg, var(--ink-100) 0%, var(--ink-200) 62%, var(--teal) 138%);
}

.page-about .about-cta__title {
  margin: 0;
  font-family: var(--font-head);
  font-size: clamp(21px, 3vw, 30px);
  font-weight: 800;
  line-height: 1.25;
  color: var(--white);
}

.page-about .about-cta__text {
  margin: 14px 0 0;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.78;
  color: var(--mist);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.page-about a:focus-visible,
.page-about .btn:focus-visible {
  outline: 2px solid var(--coral);
  outline-offset: 3px;
}

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

@media (min-width: 760px) {
  .page-about .about-rules {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-team {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    padding-bottom: 44px;
  }

  .page-about .about-team__card:nth-child(2) {
    transform: translateY(22px);
  }

  .page-about .about-team__card:nth-child(3) {
    transform: translateY(44px);
  }

  .page-about .about-audience__row {
    grid-template-columns: 56px minmax(0, 168px) minmax(0, 1fr);
    align-items: baseline;
    gap: 18px;
  }

  .page-about .about-eco {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: center;
    gap: clamp(24px, 4vw, 44px);
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
  }
}

@media (min-width: 960px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 28px);
    border-top: 0;
    padding-top: 0;
    border-left: 1px solid var(--line);
    padding-left: 18px;
  }

  .page-about .about-rail__list {
    display: block;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-rail__list .index-item {
    display: block;
  }

  .page-about .about-rail__list .index-link {
    display: flex;
    width: 100%;
    border: 0;
    border-left: 2px solid transparent;
    padding: 10px 0 10px 12px;
    margin-left: -2px;
    font-size: 14px;
    white-space: normal;
    color: var(--mist);
  }

  .page-about .about-rail__list .index-link:hover,
  .page-about .about-rail__list .index-link:focus-visible {
    border-color: var(--line);
    color: var(--white);
    background: transparent;
  }

  .page-about .about-rail__list .index-link[aria-current] {
    border-left-color: var(--cyan);
    color: var(--cyan);
    background: linear-gradient(90deg, rgba(45, 226, 230, 0.12), transparent 78%);
  }

  .page-about .about-rail__note {
    border-top: 1px solid var(--line);
    padding-top: 16px;
    margin-top: 24px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-milestone,
  .page-about .about-milestone__more,
  .page-about .about-team__card,
  .page-about .about-rail__list .index-link {
    transition: none;
  }

  .page-about .about-milestone:hover,
  .page-about .about-milestone:focus-within {
    transform: none;
  }
}
<<<END>>>