.page-about {
  --about-narrow: clamp(184px, 21vw, 252px);
  --about-gap: clamp(30px, 4.2vw, 76px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(88px, 14vh, 156px) 0 clamp(40px, 6vw, 76px);
  background:
    radial-gradient(112% 86% at 82% 2%, rgba(57, 255, 156, .10), transparent 58%),
    radial-gradient(84% 72% at 6% 24%, rgba(255, 122, 26, .09), transparent 60%),
    var(--c-night);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: 0;
  width: min(48vw, 560px);
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--c-green));
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
}

.page-about .about-hero .breadcrumb {
  margin-bottom: clamp(20px, 3vw, 34px);
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  max-width: 19ch;
  font-size: clamp(32px, 5.4vw, 66px);
  font-weight: 900;
  line-height: 1.08;
  letter-spacing: -.02em;
  color: var(--c-white);
}

.page-about .about-hero__intro {
  margin: clamp(20px, 3.2vw, 34px) 0 0;
  max-width: 46ch;
  font-size: clamp(16px, 1.3vw, 18px);
  line-height: 1.8;
  color: var(--c-grey);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(30px, 4.6vw, 54px) 0 0;
  padding: 0;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-stat {
  padding: clamp(16px, 2.1vw, 24px);
  background: var(--c-stand);
}

.page-about .about-stat dt {
  font-size: 12px;
  letter-spacing: .07em;
  line-height: 1.5;
  color: var(--c-grey);
}

.page-about .about-stat__num {
  margin: 10px 0 0;
  font-family: var(--font-num);
  font-weight: 800;
  font-size: clamp(28px, 3.8vw, 46px);
  line-height: 1;
  letter-spacing: -.01em;
  color: var(--c-white);
}

.page-about .about-stat__num--accent {
  color: var(--c-green);
}

.page-about .about-stat__unit {
  margin-left: 3px;
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 500;
  color: var(--c-grey);
}

/* ---------- 主体栅格 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(32px, 4vw, 64px);
  padding-top: clamp(44px, 6.5vw, 84px);
  padding-bottom: clamp(56px, 8vw, 108px);
}

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

/* ---------- 窄栏索引 ---------- */
.page-about .about-rail__label {
  margin: 0 0 12px;
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--c-steel);
}

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

.page-about .about-index li {
  margin: 0;
}

.page-about .about-index .index-link {
  display: block;
  margin-left: -1px;
  padding: 9px 12px;
  font-size: 14px;
  line-height: 1.55;
  color: var(--c-steel);
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.page-about .about-index .index-link:hover {
  color: var(--c-white);
}

.page-about .about-index .index-link.is-active {
  color: var(--c-green);
  border-left-color: var(--c-green);
}

.page-about .about-rail__note {
  margin: 18px 0 0;
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--c-steel);
}

/* ---------- 区块 ---------- */
.page-about .about-block {
  position: relative;
  scroll-margin-top: calc(var(--header-h) + 28px);
}

.page-about .about-block + .about-block {
  margin-top: clamp(64px, 9vw, 124px);
  padding-top: clamp(38px, 5vw, 62px);
  border-top: 1px solid var(--line);
}

.page-about .about-block__year {
  display: block;
  margin-bottom: -.06em;
  font-family: var(--font-num);
  font-weight: 800;
  font-size: clamp(50px, 11vw, 122px);
  line-height: .84;
  letter-spacing: -.035em;
  color: transparent;
  -webkit-text-stroke: 1px var(--c-steel-blue);
  user-select: none;
}

.page-about .section-title {
  margin: 10px 0 0;
  font-size: clamp(25px, 3.5vw, 42px);
  line-height: 1.16;
  letter-spacing: -.02em;
  color: var(--c-white);
}

.page-about .about-lead {
  margin: clamp(18px, 2.6vw, 28px) 0 0;
  max-width: 46ch;
  font-size: clamp(16px, 1.3vw, 18px);
  line-height: 1.8;
  color: var(--c-grey);
}

.page-about .about-prose {
  margin-top: clamp(18px, 2.6vw, 30px);
  max-width: 44ch;
  font-size: 16.5px;
  line-height: 1.85;
  color: var(--c-grey);
}

.page-about .about-prose p + p {
  margin-top: 1.15em;
}

.page-about .about-side-note {
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--c-orange);
  max-width: 34ch;
  font-size: 13px;
  line-height: 1.7;
  color: var(--c-steel);
}

/* ---------- 通用图片框 ---------- */
.page-about .about-figure {
  margin: clamp(28px, 4vw, 46px) 0 0;
}

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

.page-about .about-figure--pipe {
  margin-top: clamp(30px, 4.4vw, 52px);
}

.page-about .about-figure--venue {
  margin-top: clamp(24px, 3.4vw, 38px);
}

/* ---------- 数据链路 ---------- */
.page-about .pipeline {
  list-style: none;
  margin: clamp(26px, 3.8vw, 44px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .pipeline-step {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
  padding: clamp(20px, 2.6vw, 30px);
  background: var(--c-stand);
  transition: background .22s var(--ease);
}

.page-about .pipeline-step::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--c-green);
  opacity: 0;
  transition: opacity .22s var(--ease);
}

.page-about .pipeline-step:hover::before {
  opacity: 1;
}

.page-about .pipeline-step__idx {
  font-family: var(--font-num);
  font-weight: 800;
  font-size: clamp(26px, 3.2vw, 38px);
  line-height: 1;
  color: var(--c-steel);
  transition: color .22s var(--ease);
}

.page-about .pipeline-step:hover .pipeline-step__idx {
  color: var(--c-green);
}

.page-about .pipeline-step__title {
  margin: 0;
  font-size: clamp(18px, 1.6vw, 21px);
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-white);
}

.page-about .pipeline-step__role {
  display: inline-block;
  margin: 9px 0 0;
  padding: 3px 10px;
  font-size: 12px;
  letter-spacing: .05em;
  color: var(--c-green);
  background: rgba(57, 255, 156, .06);
  border: 1px solid rgba(57, 255, 156, .34);
}

.page-about .pipeline-step__body > p:last-child {
  margin: 12px 0 0;
  max-width: 52ch;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--c-grey);
}

/* ---------- 时间轴 ---------- */
.page-about .milestones {
  list-style: none;
  margin: clamp(26px, 3.8vw, 46px) 0 0;
  padding: 0;
}

.page-about .milestone {
  --tl-gap: clamp(22px, 3vw, 36px);
  position: relative;
  padding-left: var(--tl-gap);
  padding-bottom: clamp(26px, 3.6vw, 46px);
}

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

.page-about .milestone::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  bottom: -6px;
  width: 1px;
  background: var(--c-steel-blue);
}

.page-about .milestone:last-child::before {
  display: none;
}

.page-about .milestone::after {
  content: "";
  position: absolute;
  left: -4px;
  top: 5px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--c-green);
  box-shadow: 0 0 0 4px var(--c-night), 0 0 14px rgba(57, 255, 156, .5);
}

.page-about .milestone--current::after {
  background: var(--c-orange);
  box-shadow: 0 0 0 4px var(--c-night), 0 0 16px rgba(255, 122, 26, .6);
}

.page-about .milestone__year {
  display: block;
  font-family: var(--font-num);
  font-weight: 800;
  font-size: clamp(26px, 3.1vw, 38px);
  line-height: 1;
  letter-spacing: -.01em;
  color: var(--c-white);
}

.page-about .milestone--current .milestone__year {
  color: var(--c-orange);
}

.page-about .milestone__body h3 {
  margin: 10px 0 0;
  font-size: clamp(17px, 1.5vw, 20px);
  font-weight: 700;
  line-height: 1.45;
  color: var(--c-white);
}

.page-about .milestone__body p {
  margin: 8px 0 0;
  max-width: 52ch;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--c-grey);
}

/* ---------- 团队 ---------- */
.page-about .role-grid {
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: clamp(28px, 4vw, 46px) 0 0;
  padding: 0;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .role-card {
  padding: clamp(20px, 2.6vw, 30px);
  background: var(--c-stand);
  box-shadow: inset 0 0 0 0 rgba(57, 255, 156, 0);
  transition: box-shadow .24s var(--ease), transform .24s var(--ease);
}

.page-about .role-card:hover {
  transform: translateY(-2px);
  box-shadow: inset 0 0 0 1px rgba(57, 255, 156, .34);
}

.page-about .role-card__name {
  margin: 0;
  font-size: clamp(17px, 1.5vw, 19px);
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-white);
}

.page-about .role-card__desc {
  margin: 10px 0 0;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--c-grey);
}

.page-about .role-card__more {
  margin: 14px 0 0;
  padding-top: 13px;
  border-top: 1px dashed var(--line);
  font-size: 14px;
  line-height: 1.75;
  color: var(--c-steel);
}

/* ---------- 赛事覆盖 ---------- */
.page-about .coverage-numbers {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(26px, 3.6vw, 40px) 0 0;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .coverage-num {
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  gap: 8px;
  padding: clamp(18px, 2.4vw, 28px);
  background: var(--c-stand);
}

.page-about .coverage-num__value {
  font-family: var(--font-num);
  font-weight: 800;
  font-size: clamp(34px, 4.6vw, 58px);
  line-height: .95;
  letter-spacing: -.02em;
  color: var(--c-white);
}

.page-about .coverage-num--accent .coverage-num__value {
  color: var(--c-orange);
}

.page-about .coverage-num__unit {
  margin-left: 3px;
  font-size: .44em;
  color: var(--c-grey);
}

.page-about .coverage-num__label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--c-grey);
}

.page-about .coverage-body {
  display: grid;
  gap: clamp(26px, 3.6vw, 46px);
  margin-top: clamp(28px, 4vw, 46px);
}

.page-about .donut {
  margin: 0;
  max-width: 320px;
}

.page-about .donut svg {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .donut__num {
  font-family: var(--font-num);
  font-weight: 800;
  font-size: 52px;
  fill: var(--c-white);
}

.page-about .donut__cap {
  font-family: var(--font-sans);
  font-size: 13px;
  letter-spacing: .1em;
  fill: var(--c-grey);
}

.page-about .donut figcaption {
  margin-top: 14px;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--c-steel);
}

.page-about .coverage-detail__title {
  margin: 0;
  font-size: clamp(17px, 1.5vw, 20px);
  font-weight: 700;
  line-height: 1.45;
  color: var(--c-white);
}

.page-about .format-list {
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 18px;
}

.page-about .format-item {
  padding-left: 14px;
  border-left: 2px solid var(--c-steel-blue);
}

.page-about .format-item dt {
  font-family: var(--font-num);
  font-weight: 700;
  font-size: 14px;
  letter-spacing: .08em;
  color: var(--c-green);
}

.page-about .format-item dd {
  margin: 7px 0 0;
  max-width: 50ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--c-grey);
}

.page-about .coverage-detail__note {
  margin: 22px 0 0;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  max-width: 50ch;
  font-size: 14px;
  line-height: 1.8;
  color: var(--c-steel);
}

/* ---------- 合作方 ---------- */
.page-about .about-filters {
  margin-top: clamp(24px, 3.4vw, 36px);
}

.page-about .partner-list {
  list-style: none;
  display: grid;
  gap: clamp(14px, 1.8vw, 20px);
  margin: clamp(20px, 3vw, 32px) 0 0;
  padding: 0;
}

.page-about .partner-card {
  display: grid;
  gap: 12px;
  padding: clamp(20px, 2.6vw, 30px);
  background:
    linear-gradient(180deg, rgba(15, 26, 39, .96), rgba(15, 26, 39, .86)),
    var(--c-stand);
  border: 1px solid var(--line);
  border-left: 2px solid var(--c-orange);
  transition: transform .24s var(--ease), border-color .24s var(--ease);
}

.page-about .partner-card:hover {
  transform: translateY(-2px);
  border-left-color: var(--c-green);
}

.page-about .partner-card__head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
}

.page-about .partner-card__name {
  margin: 0;
  font-size: clamp(17px, 1.5vw, 20px);
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-white);
}

.page-about .partner-card__body p {
  margin: 0;
  max-width: 52ch;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--c-grey);
}

.page-about .partner-card__meta {
  margin-top: 12px !important;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
  font-size: 14px !important;
  line-height: 1.75 !important;
  color: var(--c-steel) !important;
}

.page-about .partner-empty {
  margin: 20px 0 0;
  font-size: 14px;
  color: var(--c-steel);
}

/* ---------- 结尾行动区 ---------- */
.page-about .about-cta {
  position: relative;
  margin-top: clamp(64px, 9vw, 122px);
  padding: clamp(26px, 3.8vw, 48px);
  background:
    radial-gradient(120% 140% at 0% 0%, rgba(57, 255, 156, .10), transparent 62%),
    var(--c-stand);
  border: 1px solid var(--line);
}

.page-about .about-cta::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--c-green), var(--c-orange));
}

.page-about .about-cta__line {
  margin: 0;
  max-width: 48ch;
  font-size: clamp(16px, 1.3vw, 18px);
  line-height: 1.8;
  color: var(--c-grey);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(22px, 3vw, 32px);
}

/* ---------- 滚动浮现 ---------- */
.js .page-about [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity .5s var(--ease), transform .5s var(--ease);
}

.js .page-about [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

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

  .page-about .pipeline-step {
    grid-template-columns: 84px minmax(0, 1fr);
    gap: clamp(16px, 2.4vw, 30px);
  }

  .page-about .pipeline-step__idx {
    padding-top: 2px;
  }

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

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

@media (min-width: 860px) {
  .page-about .coverage-body {
    grid-template-columns: minmax(0, 300px) minmax(0, 1fr);
    align-items: start;
    gap: clamp(30px, 4.4vw, 60px);
  }

  .page-about .format-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: clamp(18px, 2.4vw, 30px);
  }
}

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

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 26px);
    align-self: start;
  }

  .page-about .partner-card {
    grid-template-columns: minmax(0, 210px) minmax(0, 1fr);
    gap: clamp(20px, 3vw, 42px);
    align-items: start;
  }

  .page-about .partner-card__head {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }
}

@media (min-width: 1180px) {
  .page-about .about-block__year {
    margin-left: -2px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .js .page-about [data-reveal],
  .js .page-about [data-reveal].is-visible {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .page-about .role-card,
  .page-about .partner-card,
  .page-about .pipeline-step::before {
    transition: none;
  }

  .page-about .role-card:hover,
  .page-about .partner-card:hover {
    transform: none;
  }
}