.page-about {
  --about-cut: 18px;
  --about-cut-shape: polygon(0 0, calc(100% - var(--about-cut)) 0, 100% var(--about-cut), 100% 100%, var(--about-cut) 100%, 0 calc(100% - var(--about-cut)));
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  background: var(--ink);
  padding: 88px 0 56px;
  min-height: 540px;
  display: flex;
  align-items: flex-end;
}

.page-about .about-hero__bg {
  position: absolute;
  inset: 0;
  z-index: -2;
}

.page-about .about-hero__bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 70%;
  opacity: .38;
  filter: saturate(.72) contrast(1.04);
}

.page-about .about-hero__veil {
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(120% 85% at 10% 18%, rgba(43, 227, 208, .18), transparent 60%),
    radial-gradient(90% 70% at 92% 8%, rgba(124, 92, 255, .16), transparent 62%),
    linear-gradient(180deg, rgba(5, 9, 20, .42) 0%, rgba(5, 9, 20, .82) 58%, var(--ink) 100%);
}

.page-about .about-hero__inner {
  position: relative;
  width: 100%;
}

.page-about .about-hero__year {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin: 14px 0 0;
  line-height: .9;
}

.page-about .about-hero__year .mono {
  font-family: var(--font-mono);
  font-size: clamp(3rem, 14vw, 8.5rem);
  font-weight: 700;
  letter-spacing: -.04em;
  color: transparent;
  -webkit-text-stroke: 1.5px rgba(43, 227, 208, .62);
  line-height: .86;
}

.page-about .about-hero__year-note {
  font-size: 12px;
  letter-spacing: .24em;
  color: var(--gray);
  text-transform: uppercase;
}

.page-about .about-hero__title {
  margin: 18px 0 0;
  max-width: 15em;
  color: var(--white);
}

.page-about .about-hero__lede {
  max-width: 34em;
  margin: 20px 0 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--gray);
}

.page-about .about-hero__actions {
  margin-top: 28px;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  padding-top: 20px;
  padding-bottom: 20px;
}

/* ---------- 数字刻度尺 ---------- */
.page-about .about-scale {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--ink-2);
}

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

.page-about .about-scale__hint {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: .22em;
  color: var(--gray);
  text-transform: uppercase;
}

.page-about .about-scale__list {
  display: flex;
  gap: 0;
  margin: 0;
  padding: 0;
  list-style: none;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-scale__list > li {
  flex: 0 0 auto;
  min-width: 154px;
  scroll-snap-align: start;
  border-left: 1px solid var(--line);
}

.page-about .about-scale__list > li:last-child {
  border-right: 1px solid var(--line);
}

.page-about .about-scale__list a {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 10px 20px;
  text-decoration: none;
  color: var(--gray);
  transition: color .2s ease, background-color .2s ease;
}

.page-about .about-scale__list a:hover,
.page-about .about-scale__list a:focus-visible {
  color: var(--cyan);
  background: rgba(43, 227, 208, .06);
  outline: none;
}

.page-about .about-scale__num {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -.02em;
  color: var(--white);
}

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

.page-about .about-scale__cap {
  font-size: 13px;
  letter-spacing: .04em;
}

/* ---------- 通用章节元素 ---------- */
.page-about .about-h2 {
  margin: 12px 0 0;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: clamp(1.75rem, 5.4vw, 3rem);
  line-height: 1.14;
  letter-spacing: -.02em;
  color: var(--white);
}

.page-about .about-lede {
  max-width: 42em;
  margin: 16px 0 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--gray);
}

.page-about .about-head {
  margin-bottom: 32px;
}

.page-about .about-prose p {
  margin: 0 0 1.2em;
  font-size: 16px;
  line-height: 1.85;
  color: var(--gray);
}

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

.page-about section[id] {
  scroll-margin-top: 72px;
}

/* ---------- 起点 ---------- */
.page-about .about-start__aside {
  margin-top: 32px;
}

.page-about .about-facts {
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 8px;
}

.page-about .about-facts li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding: 11px 16px;
  background: var(--panel);
  clip-path: var(--about-cut-shape);
  font-size: 13px;
  color: var(--gray);
}

.page-about .about-facts li b {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  color: var(--cyan);
  white-space: nowrap;
}

/* ---------- 我们解决的问题 ---------- */
.page-about .about-problem__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 20px;
}

.page-about .about-problem__item {
  position: relative;
  padding: 26px 22px 24px;
  background: var(--panel);
  clip-path: var(--about-cut-shape);
  overflow: hidden;
}

.page-about .about-problem__item::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 3px;
  height: 100%;
  background: linear-gradient(180deg, var(--cyan), rgba(124, 92, 255, .5));
}

.page-about .about-problem__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .24em;
  color: var(--violet);
}

.page-about .about-problem__name {
  margin: 10px 0 0;
  font-size: 18px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--white);
}

.page-about .about-problem__text {
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--gray);
}

/* ---------- 团队 ---------- */
.page-about .about-team__aside {
  margin-top: 32px;
}

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

.page-about .about-team__roles {
  margin-top: 28px;
  display: grid;
  gap: 18px;
}

.page-about .about-team__role {
  padding: 22px 20px;
  background: var(--ink-2);
  border-top: 2px solid var(--cyan);
  clip-path: var(--about-cut-shape);
}

.page-about .about-team__role--violet {
  border-top-color: var(--violet);
}

.page-about .about-team__role--orange {
  border-top-color: var(--orange);
}

.page-about .about-team__count {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 2.6rem;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--cyan);
}

.page-about .about-team__role--violet .about-team__count {
  color: var(--violet);
}

.page-about .about-team__role--orange .about-team__count {
  color: var(--orange);
}

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

.page-about .about-team__text {
  margin: 10px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--gray);
}

/* ---------- 内容流水线 ---------- */
.page-about .about-line {
  background: var(--ink-2);
}

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

.page-about .about-line__step {
  position: relative;
  padding-left: 4px;
}

.page-about .about-line__dot {
  display: block;
  width: 11px;
  height: 11px;
  border: 2px solid var(--cyan);
  background: var(--ink-2);
  transform: rotate(45deg);
  margin-bottom: 14px;
  transition: background-color .2s ease, border-color .2s ease, box-shadow .2s ease;
}

.page-about .about-line__step-index {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .24em;
  color: var(--gray);
}

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

.page-about .about-line__duty {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--gray);
  transition: color .2s ease;
}

.page-about .about-line__step:hover .about-line__dot,
.page-about .about-line__step:focus-within .about-line__dot {
  background: var(--orange);
  border-color: var(--orange);
  box-shadow: 0 0 0 6px rgba(255, 122, 46, .14);
}

.page-about .about-line__step:hover .about-line__duty,
.page-about .about-line__step:focus-within .about-line__duty {
  color: var(--white);
}

/* ---------- 城市观赛网络 ---------- */
.page-about .about-city__aside {
  margin-top: 32px;
}

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

.page-about .about-city__grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 10px;
  margin-top: 28px;
  padding: 22px 18px;
  background: var(--ink-2);
  border: 1px solid var(--line);
  clip-path: var(--about-cut-shape);
}

.page-about .about-city__dot {
  position: relative;
  width: 100%;
  aspect-ratio: 1 / 1;
  border-radius: 50%;
  background: rgba(151, 162, 192, .26);
  transition: background-color .2s ease, box-shadow .2s ease;
}

.page-about .about-city__dot--hot {
  background: var(--cyan);
  box-shadow: 0 0 8px rgba(43, 227, 208, .55);
}

.page-about .about-city__dot[data-city] {
  cursor: help;
}

.page-about .about-city__dot[data-city]::after {
  content: attr(data-city);
  position: absolute;
  left: 50%;
  bottom: 140%;
  transform: translateX(-50%);
  white-space: nowrap;
  font-family: var(--font-sans);
  font-size: 12px;
  line-height: 1;
  padding: 7px 10px;
  background: var(--panel);
  border: 1px solid var(--line);
  color: var(--white);
  opacity: 0;
  pointer-events: none;
  transition: opacity .18s ease;
  z-index: 3;
  clip-path: var(--about-cut-shape);
}

.page-about .about-city__dot[data-city]:hover::after,
.page-about .about-city__dot[data-city]:focus-visible::after {
  opacity: 1;
}

.page-about .about-city__dot[data-city]:focus-visible {
  outline: 2px solid var(--orange);
  outline-offset: 3px;
}

.page-about .about-city__stats {
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 8px;
}

.page-about .about-city__stats li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 10px 16px;
  background: var(--panel);
  clip-path: var(--about-cut-shape);
}

.page-about .about-city__stats b {
  font-family: var(--font-mono);
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--orange);
  min-width: 3.6em;
}

.page-about .about-city__stats span {
  font-size: 14px;
  color: var(--gray);
}

/* ---------- 版本演进 ---------- */
.page-about .about-version__list {
  margin-top: 8px;
}

.page-about .about-version__list .accordion__trigger {
  display: flex;
  align-items: center;
  gap: 16px;
  width: 100%;
  text-align: left;
}

.page-about .about-version__tag {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  padding: 5px 10px;
  border: 1px solid var(--line);
  color: var(--cyan);
  clip-path: var(--about-cut-shape);
}

.page-about .about-version__name {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.5;
  color: var(--white);
}

.page-about .about-version__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.82;
  color: var(--gray);
}

/* ---------- 资质 ---------- */
.page-about .about-credit__aside {
  margin-top: 32px;
}

.page-about .about-credit__list {
  margin: 8px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 16px;
}

.page-about .about-credit__item {
  padding: 22px 20px;
  background: var(--panel);
  clip-path: var(--about-cut-shape);
}

.page-about .about-credit__tag {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .24em;
  color: var(--gray);
}

.page-about .about-credit__name {
  margin: 10px 0 0;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--white);
}

.page-about .about-credit__text {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--gray);
}

/* ---------- 接着看 ---------- */
.page-about .about-next__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 14px;
}

.page-about .about-next__item a {
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-areas:
    "index title"
    "index desc";
  align-items: baseline;
  column-gap: 18px;
  row-gap: 6px;
  padding: 20px 20px 20px 22px;
  background: var(--ink-2);
  border-left: 2px solid var(--line);
  text-decoration: none;
  transition: border-color .2s ease, background-color .2s ease, transform .2s ease;
}

.page-about .about-next__item a:hover,
.page-about .about-next__item a:focus-visible {
  border-left-color: var(--orange);
  background: var(--panel);
  outline: none;
}

.page-about .about-next__index {
  grid-area: index;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .2em;
  color: var(--cyan);
}

.page-about .about-next__title {
  grid-area: title;
  font-size: 17px;
  font-weight: 700;
  color: var(--white);
}

.page-about .about-next__desc {
  grid-area: desc;
  font-size: 14px;
  line-height: 1.7;
  color: var(--gray);
}

/* ---------- 桌面增强 ---------- */
@media (min-width: 641px) {
  .page-about .about-city__grid {
    grid-template-columns: repeat(12, 1fr);
    gap: 12px;
    padding: 26px 24px;
  }

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

  .page-about .about-problem__list {
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
  }

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

@media (min-width: 881px) {
  .page-about .about-hero {
    padding: 132px 0 76px;
    min-height: 620px;
    align-items: flex-end;
  }

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

  .page-about .about-scale__hint {
    margin-bottom: 14px;
  }

  .page-about .about-start__aside,
  .page-about .about-team__aside,
  .page-about .about-city__aside,
  .page-about .about-credit__aside {
    margin-top: 96px;
  }

  .page-about .about-team__aside,
  .page-about .about-city__aside {
    margin-top: 64px;
  }

  .page-about .about-line__track {
    position: relative;
    grid-template-columns: repeat(5, 1fr);
    gap: 0;
    padding-top: 8px;
  }

  .page-about .about-line__track::before {
    content: "";
    position: absolute;
    left: 0;
    right: 24px;
    top: 13px;
    height: 1px;
    background: linear-gradient(90deg, rgba(43, 227, 208, .65), rgba(124, 92, 255, .55) 55%, rgba(255, 122, 46, .6));
  }

  .page-about .about-line__step {
    padding: 34px 22px 0 0;
  }

  .page-about .about-line__dot {
    position: absolute;
    top: 8px;
    left: 0;
    margin-bottom: 0;
  }

  .page-about .about-line__step-index {
    letter-spacing: .2em;
  }

  .page-about .about-next__list {
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
  }

  .page-about .about-next__item a {
    height: 100%;
    align-content: start;
    grid-template-columns: 1fr;
    grid-template-areas:
      "index"
      "title"
      "desc";
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-scale__list a,
  .page-about .about-line__dot,
  .page-about .about-line__duty,
  .page-about .about-city__dot,
  .page-about .about-city__dot[data-city]::after,
  .page-about .about-next__item a {
    transition: opacity .2s ease;
  }
}
<<<END>>>