.page-about {
  --about-rail-w: 208px;
  --about-gap: 56px;
  display: block;
  padding-bottom: 88px;
  background:
    radial-gradient(900px 520px at 88% -6%, rgba(34, 224, 207, .07), transparent 62%),
    radial-gradient(760px 460px at 4% 12%, rgba(255, 107, 44, .05), transparent 60%);
}

.page-about .about-shell {
  padding-top: 16px;
}

/* ============ 首屏 ============ */
.page-about .about-hero {
  position: relative;
  padding: 34px 0 38px;
  border-bottom: 1px solid var(--yb-gridline);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: -14px 0 0 0;
  background-image:
    linear-gradient(var(--yb-gridline) 1px, transparent 1px),
    linear-gradient(90deg, var(--yb-gridline) 1px, transparent 1px);
  background-size: 52px 52px;
  opacity: .3;
  pointer-events: none;
  -webkit-mask-image: radial-gradient(circle at 26% 12%, #000 0%, transparent 74%);
  mask-image: radial-gradient(circle at 26% 12%, #000 0%, transparent 74%);
}

.page-about .about-hero > * {
  position: relative;
}

.page-about .about-hero .yb-eyebrow {
  font-family: var(--yb-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--yb-cyan);
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-family: var(--yb-display);
  font-weight: 700;
  font-size: clamp(2.15rem, 5.4vw, 4.1rem);
  line-height: 1.1;
  letter-spacing: -.005em;
  color: var(--yb-cream);
  max-width: 20ch;
}

.page-about .about-hero__lede {
  margin: 22px 0 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.72;
  color: var(--yb-rock);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px 14px;
  margin: 32px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-hero__stat {
  border-left: 3px solid var(--yb-cyan);
  padding-left: 12px;
  min-width: 0;
}

.page-about .about-hero__num {
  display: block;
  font-size: 24px;
  line-height: 1.1;
  color: var(--yb-cyan);
  letter-spacing: -.02em;
}

.page-about .about-hero__label {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  color: var(--yb-rock);
}

/* ============ 主体骨架 ============ */
.page-about .about-body {
  display: block;
  margin-top: 38px;
}

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

/* ============ 左侧版本式轨道 ============ */
.page-about .about-rail {
  display: none;
}

/* ============ 章节 ============ */
.page-about .about-sec {
  padding: 0 0 8px;
  margin-bottom: 46px;
  border-top: 1px solid var(--yb-gridline);
  padding-top: 34px;
}

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

.page-about .about-sec .yb-section__title {
  border-left: 4px solid var(--yb-cyan);
  padding-left: 13px;
  font-family: var(--yb-head);
  font-weight: 700;
}

.page-about .about-sec .yb-section__note {
  padding-left: 17px;
}

.page-about .about-sec--tail {
  margin-bottom: 0;
}

/* ============ 通用栅格 ============ */
.page-about .about-grid {
  display: grid;
  gap: 26px;
  margin-top: 26px;
}

.page-about .about-prose p {
  font-size: 15px;
  line-height: 1.75;
  color: var(--yb-rock);
}

.page-about .about-prose p + p {
  margin-top: 14px;
}

.page-about .about-prose p:first-child {
  color: var(--yb-cream);
  font-size: 16px;
}

/* ============ 侧写卡片 ============ */
.page-about .about-note-card {
  background: var(--yb-panel);
  border: 2px solid var(--yb-gridline);
  box-shadow: var(--yb-shadow);
  padding: 22px 20px 24px;
}

.page-about .about-note-card__title {
  margin: 0 0 16px;
  font-family: var(--yb-head);
  font-size: 18px;
  font-weight: 600;
  letter-spacing: .01em;
  color: var(--yb-cream);
}

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

.page-about .about-note-list li {
  position: relative;
  padding: 0 0 0 18px;
  margin-bottom: 11px;
  font-size: 14px;
  line-height: 1.65;
  color: var(--yb-rock);
}

.page-about .about-note-list li:last-child {
  margin-bottom: 0;
}

.page-about .about-note-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 7px;
  height: 7px;
  background: var(--yb-cyan);
}

/* ============ 数据流程 ============ */
.page-about .about-flow {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-flow__node {
  position: relative;
  padding: 0 0 26px 46px;
}

.page-about .about-flow__node::after {
  content: "";
  position: absolute;
  left: 15px;
  top: 34px;
  bottom: 4px;
  width: 2px;
  background: linear-gradient(180deg, var(--yb-gridline), rgba(29, 58, 82, .15));
}

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

.page-about .about-flow__node:last-child::after {
  display: none;
}

.page-about .about-flow__no {
  position: absolute;
  left: 0;
  top: 0;
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border: 2px solid var(--yb-cyan);
  background: var(--yb-night);
  color: var(--yb-cyan);
  font-size: 12px;
  box-sizing: border-box;
}

.page-about .about-flow__title {
  margin: 4px 0 0;
  font-family: var(--yb-head);
  font-size: 18px;
  font-weight: 600;
  color: var(--yb-cream);
}

.page-about .about-flow__text {
  margin: 8px 0 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--yb-rock);
}

.page-about .about-flow__out {
  margin: 9px 0 0;
  font-family: var(--yb-mono);
  font-size: 12px;
  line-height: 1.6;
  color: var(--yb-moss-soft);
  border-left: 2px solid var(--yb-moss);
  padding-left: 10px;
}

/* ============ 图 ============ */
.page-about .about-figure {
  margin: 0;
}

.page-about .about-figure--banner {
  margin-top: 26px;
}

.page-about .about-figure .yb-figure__cap {
  font-size: 12px;
  line-height: 1.6;
  color: var(--yb-rock);
}

/* ============ 覆盖范围 ============ */
.page-about .about-coverage {
  margin-top: 30px;
}

.page-about .about-filters {
  margin-bottom: 18px;
}

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

.page-about .about-cov__row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 48px 26px;
  grid-template-areas:
    "name num unit"
    "bar bar bar";
  align-items: center;
  gap: 6px 10px;
  padding: 10px 0;
  border-bottom: 1px solid rgba(29, 58, 82, .75);
}

.page-about .about-cov__name {
  grid-area: name;
  font-size: 14px;
  color: var(--yb-cream);
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.page-about .about-cov__bar {
  grid-area: bar;
  display: block;
  height: 8px;
  background: rgba(29, 58, 82, .55);
  overflow: hidden;
}

.page-about .about-cov__bar i {
  display: block;
  height: 100%;
  width: var(--p, 0%);
  background: linear-gradient(90deg, var(--yb-moss), var(--yb-cyan));
}

.page-about .about-cov__row[data-filter-tag="sport"] .about-cov__bar i {
  background: linear-gradient(90deg, var(--yb-clay), var(--yb-orange));
}

.page-about .about-cov__num {
  grid-area: num;
  text-align: right;
  font-size: 15px;
  color: var(--yb-cyan);
}

.page-about .about-cov__row[data-filter-tag="sport"] .about-cov__num {
  color: var(--yb-orange);
}

.page-about .about-cov__unit {
  grid-area: unit;
  font-size: 12px;
  color: var(--yb-rock);
}

.page-about .about-cov__note {
  margin: 22px 0 0;
  padding-left: 14px;
  border-left: 3px solid var(--yb-clay);
  font-size: 14px;
  line-height: 1.75;
  color: var(--yb-rock);
}

/* ============ 团队 ============ */
.page-about .about-roles {
  min-width: 0;
}

.page-about .about-role {
  border-left: 3px solid var(--yb-gridline);
  padding: 2px 0 2px 16px;
  margin-bottom: 22px;
  transition: border-color var(--yb-t);
}

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

.page-about .about-role:hover {
  border-color: var(--yb-cyan);
}

.page-about .about-role__head {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 4px 12px;
}

.page-about .about-role__title {
  margin: 0;
  font-family: var(--yb-head);
  font-size: 19px;
  font-weight: 600;
  color: var(--yb-cream);
}

.page-about .about-role__count {
  font-size: 12px;
  color: var(--yb-orange);
  border: 1px solid rgba(255, 107, 44, .45);
  padding: 1px 7px;
  letter-spacing: .02em;
}

.page-about .about-role__text {
  margin: 9px 0 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--yb-rock);
}

/* ============ 版本轨道 ============ */
.page-about .about-track {
  display: grid;
  gap: 14px;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-track__item {
  position: relative;
  background: var(--yb-panel);
  border: 2px solid var(--yb-gridline);
  padding: 18px 16px 20px;
  transition: border-color var(--yb-t), transform var(--yb-t);
}

.page-about .about-track__item:hover {
  border-color: var(--yb-cyan);
  transform: translateY(-3px);
}

.page-about .about-track__item.is-current {
  border-color: var(--yb-cyan);
  box-shadow: var(--yb-shadow-cyan);
}

.page-about .about-track__tag {
  display: inline-block;
  font-family: var(--yb-mono);
  font-size: 12px;
  letter-spacing: .05em;
  padding: 3px 8px;
  border: 1px solid rgba(192, 102, 63, .65);
  color: var(--yb-clay);
  margin-bottom: 12px;
}

.page-about .about-track__item.is-current .about-track__tag {
  border-color: var(--yb-cyan);
  background: var(--yb-cyan);
  color: var(--yb-night);
}

.page-about .about-track__title {
  margin: 0;
  font-family: var(--yb-head);
  font-size: 18px;
  font-weight: 600;
  line-height: 1.3;
  color: var(--yb-cream);
}

.page-about .about-track__text {
  margin: 10px 0 0;
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--yb-rock);
}

/* ============ 合作路径 ============ */
.page-about .about-steps {
  display: grid;
  gap: 16px;
  margin-top: 28px;
  padding: 0;
  list-style: none;
}

.page-about .about-steps .yb-step {
  background: rgba(18, 36, 56, .72);
  border: 2px solid var(--yb-gridline);
  padding: 20px 18px 22px;
  transition: border-color var(--yb-t);
}

.page-about .about-steps .yb-step:hover {
  border-color: var(--yb-orange);
}

.page-about .about-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
  padding-top: 24px;
  border-top: 1px solid var(--yb-gridline);
}

.page-about .about-cta__note {
  margin: 16px 0 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--yb-rock);
}

.page-about .about-cta__note a {
  color: var(--yb-cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ============ 桌面布局 ============ */
@media (min-width: 768px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-hero__num {
    font-size: 30px;
  }

  .page-about .about-cov__row {
    grid-template-columns: minmax(88px, 112px) minmax(0, 1fr) 62px 30px;
    grid-template-areas: "name bar num unit";
    gap: 14px;
    padding: 11px 0;
  }

  .page-about .about-cov__bar {
    height: 9px;
  }

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

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

@media (min-width: 900px) {
  .page-about .about-grid--split {
    grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
    align-items: start;
    gap: 30px;
  }

  .page-about .about-grid--flow {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
    align-items: start;
    gap: 32px;
  }

  .page-about .about-grid--team {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
    align-items: start;
    gap: 34px;
  }
}

@media (min-width: 1024px) {
  .page-about .about-body {
    display: grid;
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: var(--about-gap);
    align-items: start;
    margin-top: 48px;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 104px;
    align-self: start;
  }

  .page-about .about-rail__title {
    margin: 0 0 16px;
    font-family: var(--yb-mono);
    font-size: 11px;
    letter-spacing: .14em;
    text-transform: uppercase;
    color: var(--yb-rock);
  }

  .page-about .about-rail__list {
    position: relative;
    margin: 0;
    padding: 0;
    list-style: none;
  }

  .page-about .about-rail__list::before {
    content: "";
    position: absolute;
    left: 5px;
    top: 16px;
    bottom: 16px;
    width: 2px;
    background: linear-gradient(180deg, rgba(34, 224, 207, .6), var(--yb-gridline) 42%, var(--yb-gridline));
  }

  .page-about .about-rail__item {
    margin: 0;
  }

  .page-about .about-rail__link {
    position: relative;
    display: block;
    padding: 10px 0 10px 26px;
    font-size: 14px;
    line-height: 1.4;
    color: var(--yb-rock);
    text-decoration: none;
    transition: color var(--yb-t);
  }

  .page-about .about-rail__link::before {
    content: "";
    position: absolute;
    left: 0;
    top: 14px;
    width: 12px;
    height: 12px;
    box-sizing: border-box;
    border-radius: 50%;
    background: var(--yb-night);
    border: 2px solid var(--yb-gridline);
    transition: border-color var(--yb-t), background var(--yb-t), box-shadow var(--yb-t);
  }

  .page-about .about-rail__link:hover {
    color: var(--yb-cream);
  }

  .page-about .about-rail__link:hover::before {
    border-color: var(--yb-cyan);
  }

  .page-about .about-rail__link.is-active {
    color: var(--yb-cream);
  }

  .page-about .about-rail__link.is-active::before {
    border-color: var(--yb-cyan);
    background: var(--yb-cyan);
    box-shadow: 0 0 0 4px rgba(34, 224, 207, .16);
  }
}

@media (min-width: 1180px) {
  .page-about .about-track {
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 12px;
  }

  .page-about .about-steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ============ 交互增强 ============ */
@media (hover: hover) and (pointer: fine) {
  .page-about .about-flow__out {
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    margin-top: 0;
    padding-top: 0;
    padding-bottom: 0;
    transition: max-height 240ms ease, opacity 180ms ease, margin-top 240ms ease;
  }

  .page-about .about-flow__node:hover .about-flow__out,
  .page-about .about-flow__node:focus-within .about-flow__out {
    max-height: 96px;
    opacity: 1;
    margin-top: 10px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-track__item,
  .page-about .about-role,
  .page-about .about-rail__link::before,
  .page-about .about-steps .yb-step {
    transition: none;
  }

  .page-about .about-track__item:hover {
    transform: none;
  }

  .page-about .about-hero::before {
    opacity: .22;
  }
}
<<<END>>>

.page-about {
  --p: 1rem;
}