.page-about {
  --moss-up: #7FAE8E;
  --violet-up: #A78DF5;
  display: block;
}

.page-about .about-hero {
  position: relative;
  padding: 36px 0 64px;
  background:
    radial-gradient(120% 90% at 88% 0%, rgba(47, 211, 232, .10), transparent 58%),
    radial-gradient(90% 70% at 6% 8%, rgba(142, 108, 240, .09), transparent 62%),
    linear-gradient(180deg, var(--ink-deep) 0%, var(--ink) 78%);
  border-bottom: 1px solid var(--line);
}

.page-about .crumbs {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 34px;
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--text-mute);
}

.page-about .crumbs a {
  color: var(--silver);
  text-decoration: none;
  transition: color .2s var(--ease);
}

.page-about .crumbs a:hover,
.page-about .crumbs a:focus-visible {
  color: var(--cyan);
}

.page-about .crumbs__sep {
  color: var(--line-strong);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 34px;
}

.page-about .eyebrow {
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--cyan);
  margin: 0 0 14px;
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(30px, 7.4vw, 54px);
  font-weight: 700;
  line-height: 1.14;
  letter-spacing: -.01em;
  color: var(--text);
  margin: 0 0 20px;
}

.page-about .lede {
  font-size: 16px;
  line-height: 1.85;
  color: var(--text-dim);
  max-width: 40em;
  margin: 0;
}

.page-about .about-hero__facts {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 26px;
  list-style: none;
  margin: 28px 0 0;
  padding: 20px 0 0;
  border-top: 1px solid var(--line);
}

.page-about .about-hero__facts li {
  font-size: 13px;
  color: var(--text-mute);
  letter-spacing: .02em;
}

.page-about .about-hero__facts b {
  display: block;
  font-family: var(--font-num);
  font-size: 19px;
  font-weight: 600;
  letter-spacing: .08em;
  color: var(--cyan);
  margin-bottom: 4px;
}

.page-about .media-frame {
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--ink-2);
}

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

.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
  padding: 44px 0 76px;
}

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

.page-about .about-rail__label {
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .22em;
  color: var(--text-mute);
  margin: 0 0 16px;
}

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

.page-about .about-rail__link {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 9px 0 9px 16px;
  font-size: 13.5px;
  color: var(--text-dim);
  text-decoration: none;
  transition: color .2s var(--ease);
}

.page-about .about-rail__link::before {
  content: "";
  position: absolute;
  left: -1px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--cyan);
  transform: scaleY(0);
  transform-origin: top center;
  transition: transform .24s var(--ease);
}

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

.page-about .about-rail__link:hover::before,
.page-about .about-rail__link:focus-visible::before {
  transform: scaleY(1);
}

.page-about .about-rail__no {
  font-family: var(--font-num);
  font-size: 11.5px;
  letter-spacing: .12em;
  color: var(--cyan);
}

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

.page-about .about-chapter {
  padding: 38px 0 44px;
  border-top: 1px solid var(--line);
}

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

.page-about .about-chapter__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 18px;
}

.page-about .about-no {
  font-family: var(--font-num);
  font-size: 12.5px;
  letter-spacing: .18em;
  color: var(--cyan);
  flex: none;
}

.page-about .about-chapter h2 {
  font-family: var(--font-display);
  font-size: clamp(21px, 3.4vw, 29px);
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: -.005em;
  color: var(--text);
  margin: 0;
}

.page-about .about-chapter__body {
  font-size: 16px;
  line-height: 1.82;
  color: var(--text-dim);
}

.page-about .about-chapter__body p {
  margin: 0 0 16px;
  max-width: 42em;
  overflow-wrap: break-word;
}

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

.page-about .hl-cyan {
  font-family: var(--font-num);
  letter-spacing: .06em;
  color: var(--cyan);
  font-weight: 600;
}

.page-about .hl-amber {
  font-family: var(--font-num);
  letter-spacing: .06em;
  color: var(--amber);
  font-weight: 600;
}

/* 定位：指标条 */
.page-about .about-metrics {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  list-style: none;
  margin: 28px 0 0;
  padding: 1px;
  background: var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-metrics li {
  background: var(--ink-2);
  padding: 18px 16px;
  min-width: 0;
}

.page-about .mv {
  display: block;
  font-family: var(--font-num);
  font-size: 22px;
  font-weight: 600;
  letter-spacing: .06em;
  color: var(--cyan);
  line-height: 1.2;
}

.page-about .mv--amber {
  color: var(--amber);
}

.page-about .mv--moss {
  color: var(--moss-up);
}

.page-about .mv-unit {
  font-size: 13px;
  letter-spacing: .08em;
  margin-left: 3px;
}

.page-about .ml {
  display: block;
  margin-top: 7px;
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--text-mute);
}

/* 使用者卡片 */
.page-about .about-cards {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 24px;
}

.page-about .about-card {
  position: relative;
  padding: 22px 20px 22px;
  background: linear-gradient(158deg, rgba(18, 41, 61, .95) 0%, rgba(10, 26, 42, .95) 100%);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-card::after {
  content: "";
  position: absolute;
  left: 20px;
  right: 20px;
  bottom: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--cyan), rgba(47, 211, 232, 0));
}

.page-about .about-card__tag {
  display: inline-block;
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--cyan);
  border: 1px solid rgba(47, 211, 232, .34);
  border-radius: 999px;
  padding: 3px 10px;
  margin-bottom: 14px;
}

.page-about .about-card__tag.tag--violet {
  color: var(--violet-up);
  border-color: rgba(142, 108, 240, .40);
}

.page-about .about-card__tag.tag--moss {
  color: var(--moss-up);
  border-color: rgba(127, 174, 142, .40);
}

.page-about .about-card h3 {
  font-family: var(--font-display);
  font-size: 17.5px;
  font-weight: 700;
  color: var(--text);
  margin: 0 0 10px;
  line-height: 1.4;
}

.page-about .about-card p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-dim);
}

/* 时间线 */
.page-about .about-timeline {
  list-style: none;
  margin: 26px 0 0;
  padding: 0 0 0 26px;
  position: relative;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan) 0%, rgba(142, 108, 240, .55) 52%, rgba(47, 211, 232, 0) 100%);
}

.page-about .tl-item {
  position: relative;
  padding-bottom: 26px;
}

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

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 6px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--ink);
  border: 1px solid var(--cyan);
  box-shadow: 0 0 0 3px rgba(47, 211, 232, .12);
}

.page-about .tl-item--violet::before {
  border-color: var(--violet);
  box-shadow: 0 0 0 3px rgba(142, 108, 240, .14);
}

.page-about .tl-item--amber::before {
  border-color: var(--amber);
  box-shadow: 0 0 0 3px rgba(240, 169, 59, .14);
}

.page-about .tl-item--moss::before {
  border-color: var(--moss-up);
  box-shadow: 0 0 0 3px rgba(127, 174, 142, .16);
}

.page-about .tl-when {
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--cyan);
  margin: 0 0 6px;
}

.page-about .tl-item--violet .tl-when {
  color: var(--violet-up);
}

.page-about .tl-item--amber .tl-when {
  color: var(--amber);
}

.page-about .tl-item--moss .tl-when {
  color: var(--moss-up);
}

.page-about .tl-title {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  color: var(--text);
  line-height: 1.5;
  margin: 0 0 8px;
}

.page-about .tl-text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-dim);
  max-width: 38em;
}

.page-about .about-figure {
  margin: 30px 0 0;
}

.page-about .about-figure figcaption {
  margin-top: 12px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--text-mute);
  max-width: 40em;
}

/* 团队 */
.page-about .about-units {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: 24px;
}

.page-about .about-unit {
  padding: 20px 20px 18px;
  background: rgba(18, 41, 61, .68);
  border: 1px solid var(--line);
  border-left: 2px solid var(--cyan);
  border-radius: var(--radius-sm) var(--radius) var(--radius) var(--radius-sm);
}

.page-about .about-unit__tag {
  display: block;
  font-family: var(--font-num);
  font-size: 11.5px;
  letter-spacing: .2em;
  color: var(--cyan);
  margin-bottom: 8px;
}

.page-about .about-unit h3 {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  color: var(--text);
  margin: 0 0 8px;
}

.page-about .about-unit p {
  margin: 0 0 12px;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--text-dim);
}

.page-about .about-unit .collapse__trigger {
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--cyan);
  background: none;
  border: 0;
  border-bottom: 1px solid rgba(47, 211, 232, .35);
  padding: 2px 0;
  cursor: pointer;
  transition: border-color .2s var(--ease), color .2s var(--ease);
}

.page-about .about-unit .collapse__trigger:hover,
.page-about .about-unit .collapse__trigger:focus-visible {
  color: var(--text);
  border-color: var(--cyan);
}

.page-about .about-unit .collapse__panel {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
}

.page-about .about-unit .collapse__panel p {
  margin: 0;
  font-size: 14px;
  color: var(--text-mute);
}

/* 运营准则 */
.page-about .about-rules {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .about-rules li {
  padding: 18px 18px 16px;
  background: rgba(18, 41, 61, .55);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.page-about .about-rules__k {
  display: inline-block;
  font-family: var(--font-num);
  font-size: 11.5px;
  letter-spacing: .18em;
  color: var(--amber);
  border-bottom: 1px solid rgba(240, 169, 59, .35);
  padding-bottom: 2px;
  margin-bottom: 10px;
}

.page-about .about-rules p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-dim);
}

/* 服务保障 */
.page-about .about-support {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  margin-top: 22px;
  padding: 24px 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    linear-gradient(140deg, rgba(78, 122, 94, .18) 0%, rgba(10, 26, 42, .9) 58%);
}

.page-about .about-support__big {
  display: block;
  font-family: var(--font-num);
  font-size: clamp(24px, 6vw, 34px);
  font-weight: 600;
  letter-spacing: .08em;
  color: var(--moss-up);
  line-height: 1.2;
}

.page-about .about-support__sub {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--text-mute);
}

.page-about .about-support__body p {
  margin: 0 0 16px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-dim);
}

.page-about .about-priority {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 9px;
}

.page-about .about-priority li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  font-size: 14.5px;
  color: var(--text);
  padding-bottom: 9px;
  border-bottom: 1px solid var(--line);
}

.page-about .about-priority li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .about-priority__k {
  flex: none;
  font-family: var(--font-num);
  font-size: 11.5px;
  letter-spacing: .16em;
  color: var(--violet-up);
  min-width: 3em;
}

/* 下一步 */
.page-about .about-chapter--next {
  padding-bottom: 8px;
}

.page-about .about-next {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: 22px;
}

.page-about .about-next__card {
  display: block;
  padding: 20px 20px 18px;
  color: inherit;
  text-decoration: none;
  background: rgba(10, 26, 42, .7);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: border-color .22s var(--ease), transform .22s var(--ease), background-color .22s var(--ease);
}

.page-about .about-next__card:hover,
.page-about .about-next__card:focus-visible {
  border-color: rgba(47, 211, 232, .5);
  background: rgba(18, 41, 61, .9);
  transform: translateY(-2px);
}

.page-about .about-next__no {
  display: block;
  font-family: var(--font-num);
  font-size: 11.5px;
  letter-spacing: .2em;
  color: var(--cyan);
  margin-bottom: 10px;
}

.page-about .about-next__card h3 {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  color: var(--text);
  margin: 0 0 8px;
}

.page-about .about-next__card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-mute);
}

/* —— 平板 —— */
@media (min-width: 720px) {
  .page-about .about-metrics {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-cards {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
  }

  .page-about .about-units {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
  }

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

  .page-about .about-next {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
  }
}

/* —— 桌面 —— */
@media (min-width: 1024px) {
  .page-about .about-hero {
    padding: 44px 0 82px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.02fr);
    gap: 56px;
    align-items: center;
  }

  .page-about .lede {
    font-size: 17px;
  }

  .page-about .about-shell {
    grid-template-columns: 172px minmax(0, 1fr);
    gap: 60px;
    padding: 64px 0 96px;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 96px;
    align-self: start;
  }

  .page-about .about-chapter {
    padding: 46px 0 54px;
  }

  .page-about .about-chapter__body {
    font-size: 16.5px;
  }

  .page-about .about-support {
    grid-template-columns: minmax(0, .82fr) minmax(0, 1.18fr);
    gap: 34px;
    align-items: center;
    padding: 30px 28px;
  }
}

@media (min-width: 1440px) {
  .page-about .about-shell {
    grid-template-columns: 196px minmax(0, 1fr);
    gap: 72px;
  }
}

/* 动效降级 */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-next__card {
    transition: none;
  }

  .page-about .about-next__card:hover,
  .page-about .about-next__card:focus-visible {
    transform: none;
  }

  .page-about .about-rail__link::before {
    transition: none;
  }
}
<<<END>>>