.page-about {
  --ab-gutter: 20px;
  --ab-rail: 120px;
  background: var(--paper);
  color: var(--ink);
}

.page-about .page-about__crumbs {
  padding-block: 16px 4px;
}

/* ============ 首屏 ============ */
.page-about .about-hero {
  position: relative;
  margin-top: 14px;
  background-color: var(--green-900);
  color: var(--paper);
  overflow: hidden;
  isolation: isolate;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(246, 244, 239, .07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(246, 244, 239, .07) 1px, transparent 1px);
  background-size: 56px 56px;
  pointer-events: none;
  z-index: 0;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -80px;
  top: -60px;
  width: 280px;
  height: 280px;
  border: 1px solid rgba(18, 183, 160, .35);
  transform: rotate(-18deg);
  pointer-events: none;
  z-index: 0;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  padding-block: 44px 40px;
  display: grid;
  gap: 32px;
}

.page-about .about-hero__flag {
  margin: 0 0 16px;
  font-size: 12px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--green-300);
}

.page-about .about-hero h1 {
  margin: 0 0 18px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(28px, 7vw, 52px);
  line-height: 1.14;
  letter-spacing: -.02em;
  color: var(--paper);
}

.page-about .about-hero__lead {
  margin: 0 0 26px;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.8;
  color: rgba(246, 244, 239, .82);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-hero__stats {
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: rgba(246, 244, 239, .16);
  border: 1px solid rgba(246, 244, 239, .16);
}

.page-about .hero-stat {
  background: var(--green-900);
  padding: 14px 14px 16px;
}

.page-about .hero-stat__k {
  margin: 0 0 8px;
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--green-300);
}

.page-about .hero-stat__v {
  margin: 0;
  display: flex;
  align-items: baseline;
  gap: 4px;
  font-family: var(--font-mono);
  font-size: clamp(22px, 6vw, 30px);
  font-weight: 700;
  font-style: italic;
  color: var(--yellow);
  letter-spacing: -.02em;
}

.page-about .hero-stat__unit {
  font-size: 13px;
  font-style: normal;
  color: rgba(246, 244, 239, .6);
}

/* ============ 章节索引横条 ============ */
.page-about .about-index {
  background: var(--paper-pure);
  border-bottom: 1px solid var(--rule);
}

.page-about .about-index__inner {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .about-index__list {
  display: flex;
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  min-width: max-content;
  background: var(--rule);
}

.page-about .about-index__list a {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 13px 16px;
  background: var(--paper-pure);
  color: var(--ink);
  text-decoration: none;
  font-size: 14px;
  white-space: nowrap;
  border-bottom: 3px solid transparent;
  transition: background .2s var(--ease), border-color .2s var(--ease);
}

.page-about .about-index__list a .mono {
  font-size: 12px;
  color: var(--green-600);
  letter-spacing: .06em;
}

.page-about .about-index__list a:hover,
.page-about .about-index__list a:focus-visible {
  background: #EDF6F1;
  border-bottom-color: var(--green-600);
  outline: none;
}

/* ============ 章节通用 ============ */
.page-about .about-chapter {
  padding-block: 52px;
  background: var(--paper);
}

.page-about .about-chapter--dark {
  background: var(--green-900);
  color: var(--paper);
}

.page-about .about-chapter--band {
  background: var(--green-300);
  color: var(--ink);
}

.page-about .about-chapter__inner {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

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

.page-about .about-chapter__num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 38px;
  height: 28px;
  padding-inline: 8px;
  background: var(--green-600);
  color: var(--paper-pure);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .06em;
}

.page-about .about-chapter--dark .about-chapter__num {
  background: var(--yellow);
  color: var(--ink);
}

.page-about .about-chapter--band .about-chapter__num {
  background: var(--green-900);
  color: var(--paper);
}

.page-about .about-chapter__year {
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--ink-soft);
}

.page-about .about-chapter--dark .about-chapter__year {
  color: var(--green-300);
}

.page-about .about-chapter__title {
  margin: 0 0 16px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(22px, 5.4vw, 34px);
  line-height: 1.24;
  letter-spacing: -.02em;
  color: inherit;
}

.page-about .about-chapter__intro {
  margin: 0 0 26px;
  max-width: 60ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.page-about .about-chapter--dark .about-chapter__intro {
  color: rgba(246, 244, 239, .78);
}

.page-about .about-chapter__tail {
  margin: 22px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
  border-left: 3px solid var(--green-600);
  padding-left: 14px;
}

.page-about .about-chapter__note {
  margin-top: 18px;
}

.page-about .about-chapter__wide {
  margin-top: 32px;
}

.page-about .about-chapter__cols {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

.page-about .about-chapter__text p {
  margin: 0 0 14px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink);
}

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

/* ============ 01 起点 ============ */
.page-about #ch-start .about-chapter__cols {
  align-items: start;
}

/* ============ 02 版本线 ============ */
.page-about .vline {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid rgba(246, 244, 239, .18);
}

.page-about .vline__item {
  border-bottom: 1px solid rgba(246, 244, 239, .18);
}

.page-about .vline__det {
  padding: 14px 0;
}

.page-about .vline__sum {
  display: flex;
  align-items: center;
  gap: 14px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .vline__sum:focus-visible {
  outline: 2px solid var(--teal);
  outline-offset: 3px;
}

.page-about .vline__tag {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 56px;
  height: 30px;
  background: var(--green-600);
  color: var(--paper-pure);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .06em;
}

.page-about .vline__item:nth-child(2) .vline__tag {
  background: var(--teal);
  color: var(--green-900);
}

.page-about .vline__item:nth-child(3) .vline__tag {
  background: var(--yellow);
  color: var(--ink);
}

.page-about .vline__item:nth-child(4) .vline__tag {
  background: var(--red);
  color: var(--paper-pure);
}

.page-about .vline__name {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 17px;
  color: var(--paper);
}

.page-about .vline__chev {
  margin-left: auto;
  width: 10px;
  height: 10px;
  border-right: 2px solid var(--green-300);
  border-bottom: 2px solid var(--green-300);
  transform: rotate(45deg);
  transition: transform .2s var(--ease);
}

.page-about .vline__det[open] .vline__chev {
  transform: rotate(-135deg);
}

.page-about .vline__desc {
  margin: 12px 0 2px;
  padding-left: 14px;
  border-left: 2px solid rgba(111, 191, 151, .5);
  font-size: 15px;
  line-height: 1.8;
  color: rgba(246, 244, 239, .82);
  max-width: 62ch;
}

/* ============ 03 团队 ============ */
.page-about .crew-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--rule);
  border: 1px solid var(--rule);
}

.page-about .crew-card {
  background: var(--paper-pure);
  padding: 20px 18px 22px;
}

.page-about .crew-card__num {
  display: block;
  font-size: 32px;
  font-weight: 700;
  font-style: italic;
  letter-spacing: -.03em;
  color: var(--green-600);
  line-height: 1;
  margin-bottom: 10px;
}

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

.page-about .crew-card__desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink-soft);
}

.page-about .crew-numbers {
  margin-top: 26px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--rule);
  border: 1px solid var(--rule);
}

.page-about .crew-numbers__item {
  background: var(--paper-pure);
  padding: 14px 16px;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px;
}

.page-about .crew-numbers__v {
  font-size: 24px;
  font-weight: 700;
  font-style: italic;
  color: var(--red);
  letter-spacing: -.02em;
}

.page-about .crew-numbers__u {
  font-size: 13px;
  color: var(--ink-soft);
}

.page-about .crew-numbers__k {
  flex-basis: 100%;
  font-size: 14px;
  color: var(--ink);
}

/* ============ 04 覆盖版图 ============ */
.page-about .coverage-sub {
  margin: 0 0 12px;
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 16px;
  color: var(--green-900);
}

.page-about .coverage-sub:not(:first-of-type) {
  margin-top: 28px;
}

.page-about .coverage-sub__n {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 30px;
  height: 22px;
  padding-inline: 6px;
  background: var(--green-900);
  color: var(--paper-pure);
  font-size: 12px;
  font-weight: 700;
}

.page-about .league-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: rgba(11, 59, 36, .25);
  border: 1px solid rgba(11, 59, 36, .25);
}

.page-about .league-chip {
  background: rgba(246, 244, 239, .55);
  padding: 12px 14px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 15px;
  color: var(--green-900);
  letter-spacing: .02em;
}

.page-about .coverage-line {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--green-900);
  max-width: 62ch;
}

.page-about .coverage-figures {
  margin-top: 26px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  padding-top: 20px;
  border-top: 1px dashed rgba(11, 59, 36, .35);
}

.page-about .coverage-figure {
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.page-about .coverage-figure__v {
  font-size: 26px;
  font-weight: 700;
  font-style: italic;
  letter-spacing: -.03em;
  color: var(--green-900);
}

.page-about .coverage-figure__k {
  font-size: 14px;
  color: rgba(11, 59, 36, .8);
}

/* ============ 05 合作与认可 ============ */
.page-about .partner-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about .partner-card {
  background: var(--paper-pure);
  border: 1px solid var(--rule);
  border-left: 3px solid var(--green-600);
  padding: 20px 18px;
}

.page-about .partner-card__title {
  margin: 12px 0 8px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 17px;
  color: var(--ink);
}

.page-about .partner-card__desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink-soft);
}

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

.page-about .award-head {
  margin: 34px 0 14px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 16px;
  color: var(--ink);
  padding-bottom: 10px;
  border-bottom: 1px solid var(--rule);
}

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

.page-about .award-item {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 14px;
  padding: 14px 0;
  border-bottom: 1px solid var(--rule);
}

.page-about .award-item__y {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 54px;
  height: 26px;
  background: var(--yellow);
  color: var(--ink);
  font-size: 13px;
  font-weight: 700;
}

.page-about .award-item__t {
  font-size: 15px;
  color: var(--ink);
  line-height: 1.6;
}

/* ============ 06 服务 ============ */
.page-about .service-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: rgba(246, 244, 239, .18);
  border: 1px solid rgba(246, 244, 239, .18);
}

.page-about .service-row {
  background: var(--green-900);
  padding: 18px 16px 20px;
}

.page-about .service-row__t {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 16px;
  color: var(--paper);
}

.page-about .service-row__d {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: rgba(246, 244, 239, .78);
}

.page-about .about-cta {
  margin-top: 30px;
  padding-top: 24px;
  border-top: 1px solid rgba(246, 244, 239, .2);
}

.page-about .about-cta__t {
  margin: 0 0 16px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(18px, 4.4vw, 24px);
  color: var(--paper);
}

.page-about .about-cta .btn-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-cta__n {
  margin: 16px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: rgba(246, 244, 239, .7);
}

.page-about .about-cta__n a {
  color: var(--teal);
  text-decoration: underline;
  text-underline-offset: 3px;
}

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

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

  .page-about .crew-numbers {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

  .page-about .coverage-figures {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
  }

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

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

@media (min-width: 900px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.55fr) minmax(0, 1fr);
    align-items: end;
    gap: 48px;
    padding-block: 72px 64px;
  }

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

  .page-about .about-chapter {
    padding-block: 72px;
  }

  .page-about #ch-versions,
  .page-about #ch-coverage {
    padding-block: 88px;
  }

  .page-about #ch-partners {
    padding-block: 104px;
  }

  .page-about #ch-service {
    padding-block: 112px;
  }

  .page-about .about-chapter__inner {
    grid-template-columns: var(--ab-rail) minmax(0, 1fr);
    gap: 44px;
  }

  .page-about .about-chapter__rail {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
    padding-top: 4px;
  }

  .page-about .about-chapter__cols {
    grid-template-columns: minmax(0, 1fr) minmax(0, 320px);
    gap: 44px;
    align-items: start;
  }

  .page-about .about-chapter__wide {
    margin-top: 44px;
  }

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

  .page-about .partner-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
  }

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

@media (min-width: 1100px) {
  .page-about .about-chapter__inner {
    gap: 64px;
  }

  .page-about .about-chapter__cols {
    grid-template-columns: minmax(0, 1fr) minmax(0, 360px);
    gap: 56px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__list a,
  .page-about .vline__chev {
    transition: none;
  }
}
<<<END>>>