.page-about {
  --about-rail-w: 220px;
  --about-gap: clamp(28px, 4vw, 64px);
  background-color: var(--cs-navy);
  color: var(--cs-ivory);
  font-family: var(--cs-font-body);
  overflow-x: hidden;
}

/* ---------- 首屏封面 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(84px, 14vh, 150px) 0 clamp(40px, 6vh, 72px);
  border-bottom: 1px solid var(--cs-line);
  background:
    radial-gradient(1100px 480px at 14% -18%, rgba(212, 175, 55, 0.18), transparent 64%),
    radial-gradient(760px 420px at 92% 8%, rgba(30, 122, 76, 0.22), transparent 68%),
    linear-gradient(178deg, #0d2444 0%, #0B1E3A 46%, #091729 100%);
}

.page-about .about-hero__grid {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(245, 242, 234, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(245, 242, 234, 0.045) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.95), rgba(0, 0, 0, 0));
}

.page-about .about-hero__inner {
  position: relative;
  max-width: var(--cs-max);
  margin: 0 auto;
  padding: 0 var(--cs-gutter);
}

.page-about .about-hero__coord {
  margin: 26px 0 14px;
  font-family: var(--cs-font-data);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cs-steel);
}

.page-about .about-hero__coordnum {
  color: var(--cs-gold);
}

.page-about .about-hero__title {
  margin: 0 0 22px;
  max-width: 17em;
  font-family: var(--cs-font-display);
  font-weight: 900;
  font-size: clamp(32px, 6.2vw, 72px);
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--cs-ivory);
}

.page-about .about-hero__lede {
  margin: 0;
  max-width: 52em;
  font-size: clamp(15px, 1.7vw, 18px);
  line-height: 1.8;
  color: rgba(245, 242, 234, 0.78);
}

.page-about .about-hero__meta {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  gap: 1px;
  margin: clamp(32px, 5vh, 56px) 0 0;
  border-top: 1px solid var(--cs-line);
  padding-top: 20px;
}

.page-about .about-hero__meta > div {
  padding-right: 16px;
}

.page-about .about-hero__meta dt {
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cs-steel);
}

.page-about .about-hero__meta dd {
  margin: 8px 0 0;
  font-size: 15px;
  color: var(--cs-ivory);
}

.page-about .about-hero__meta dd.cs-mono {
  font-size: 22px;
  color: var(--cs-gold);
}

/* ---------- 轨道布局 ---------- */
.page-about .about-rail {
  max-width: var(--cs-max);
  margin: 0 auto;
  padding: clamp(28px, 4vh, 48px) var(--cs-gutter) clamp(48px, 8vh, 96px);
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
}

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

.page-about .about-index__title {
  margin: 0 0 10px;
  font-family: var(--cs-font-data);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cs-steel);
}

.page-about .about-index__list {
  display: flex;
  gap: 6px;
  margin: 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  border-bottom: 1px solid var(--cs-line);
  scrollbar-width: thin;
}

.page-about .about-index__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 6px 10px;
  white-space: nowrap;
  border-bottom: 2px solid transparent;
  color: var(--cs-steel);
  font-size: 13px;
  text-decoration: none;
  transition: color var(--cs-t), border-color var(--cs-t);
}

.page-about .about-index__num {
  font-size: 11px;
  color: inherit;
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible,
.page-about .about-index__link.is-active {
  color: var(--cs-gold);
  border-bottom-color: var(--cs-gold);
}

.page-about .about-rail__body {
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

/* ---------- 分区外壳 ---------- */
.page-about .about-sec {
  position: relative;
  padding: clamp(28px, 4vw, 56px) clamp(20px, 3.2vw, 52px);
  border: 1px solid var(--cs-line);
  border-radius: var(--cs-radius);
  background-color: var(--cs-navy);
}

.page-about .about-sec--panel {
  background:
    linear-gradient(180deg, rgba(20, 41, 76, 0.96), rgba(11, 30, 58, 0.98));
}

.page-about .about-sec--ivory {
  background-color: var(--cs-ivory);
  border-color: rgba(10, 12, 16, 0.14);
  color: var(--cs-ink);
}

.page-about .about-sec--ivory .cs-coord,
.page-about .about-sec--ivory .about-sec__lede {
  color: rgba(10, 12, 16, 0.62);
}

.page-about .about-sec--ivory .about-sec__title {
  color: var(--cs-ink);
}

.page-about .about-sec--close {
  border-color: rgba(212, 175, 55, 0.34);
  background:
    radial-gradient(680px 260px at 8% 0%, rgba(212, 175, 55, 0.16), transparent 70%),
    var(--cs-navy);
}

.page-about .cs-coord {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-family: var(--cs-font-data);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cs-steel);
}

.page-about .cs-coord__num {
  font-size: 13px;
  color: var(--cs-steel);
  transition: color var(--cs-t);
}

.page-about .about-sec.is-active .cs-coord__num {
  color: var(--cs-gold);
}

.page-about .about-sec__title {
  margin: 14px 0 0;
  font-family: var(--cs-font-display);
  font-weight: 900;
  font-size: clamp(24px, 3.4vw, 40px);
  line-height: 1.18;
  letter-spacing: -0.01em;
  color: var(--cs-ivory);
}

.page-about .about-sec__title--tight {
  margin-top: 0;
}

.page-about .about-sec__lede {
  margin: 18px 0 0;
  max-width: 46em;
  font-size: clamp(14px, 1.55vw, 16px);
  line-height: 1.8;
  color: rgba(245, 242, 234, 0.7);
}

/* ---------- 正文 ---------- */
.page-about .about-body p {
  margin: 0 0 1.1em;
  font-size: clamp(15px, 1.55vw, 17px);
  line-height: 1.82;
}

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

.page-about .about-sec--dark .about-body,
.page-about .about-sec--panel .about-body {
  color: rgba(245, 242, 234, 0.8);
}

.page-about .about-sec--ivory .about-body {
  color: rgba(10, 12, 16, 0.78);
}

.page-about .about-body a {
  color: var(--cs-gold);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .about-sec--ivory .about-body a {
  color: #8a6a0f;
}

.page-about .about-quote {
  margin: 26px 0 0;
  padding: 6px 0 6px 20px;
  border-left: 3px solid var(--cs-gold);
  font-family: var(--cs-font-editorial);
  font-weight: 700;
  font-size: clamp(17px, 2.1vw, 23px);
  line-height: 1.6;
  color: var(--cs-gold-hi);
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 0;
  position: relative;
}

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

.page-about .cs-media__frame {
  border-bottom: 1px solid var(--cs-line-strong);
}

.page-about .about-sec--ivory .cs-media__frame {
  border-bottom-color: rgba(10, 12, 16, 0.24);
}

.page-about .cs-media__index {
  position: absolute;
  top: 0;
  left: 0;
  padding: 4px 8px;
  font-size: 11px;
  letter-spacing: 0.1em;
  background: var(--cs-navy);
  color: var(--cs-gold);
  border-right: 1px solid var(--cs-line-strong);
  border-bottom: 1px solid var(--cs-line-strong);
}

.page-about .cs-media__caption {
  margin: 10px 0 0;
  font-size: 12px;
  line-height: 1.6;
  color: var(--cs-steel);
}

.page-about .about-sec--ivory .cs-media__caption {
  color: rgba(10, 12, 16, 0.55);
}

/* ---------- 起点分区 ---------- */
.page-about .about-origin {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3vw, 40px);
  margin-top: 22px;
}

/* ---------- 规模分区 ---------- */
.page-about .about-figures {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: clamp(18px, 2.4vw, 34px);
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-figures__item {
  padding-top: 14px;
  border-top: 1px solid var(--cs-line-strong);
}

.page-about .about-sec--ivory .about-figures__item {
  border-top-color: rgba(10, 12, 16, 0.28);
}

.page-about .about-figures__num {
  margin: 0;
  font-family: var(--cs-font-data);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  font-size: clamp(30px, 4.4vw, 48px);
  line-height: 1;
  color: var(--cs-gold);
}

.page-about .about-sec--ivory .about-figures__num {
  color: var(--cs-ink);
  box-shadow: inset 0 -3px 0 var(--cs-gold);
}

.page-about .about-figures__unit {
  margin-left: 4px;
  font-size: 13px;
  font-weight: 400;
  color: var(--cs-steel);
}

.page-about .about-figures__label {
  margin: 12px 0 0;
  font-size: 13px;
  line-height: 1.65;
  color: rgba(245, 242, 234, 0.68);
}

.page-about .about-sec--ivory .about-figures__label {
  color: rgba(10, 12, 16, 0.66);
}

.page-about .about-scale__text {
  margin-top: 34px;
}

.page-about .about-leagues {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-leagues .cs-tag {
  font-size: 12px;
  letter-spacing: 0.06em;
}

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

/* ---------- 团队分区 ---------- */
.page-about .about-team {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3vw, 36px);
  margin-top: 24px;
}

.page-about .about-flow {
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
  counter-reset: flow;
}

.page-about .about-flow__step {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 14px;
  padding: 16px 0;
  border-top: 1px solid var(--cs-line);
}

.page-about .about-flow__step:last-child {
  border-bottom: 1px solid var(--cs-line);
}

.page-about .about-flow__num {
  font-size: 13px;
  color: var(--cs-gold);
  padding-top: 3px;
}

.page-about .about-flow__title {
  margin: 0 0 6px;
  font-family: var(--cs-font-body);
  font-weight: 700;
  font-size: 16px;
  color: var(--cs-ivory);
}

.page-about .about-flow__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: rgba(245, 242, 234, 0.7);
}

.page-about .about-figures--inline {
  margin-top: 30px;
}

/* ---------- 版本时间线 ---------- */
.page-about .about-figure--timeline {
  margin: 28px 0 0;
}

.page-about .about-timeline {
  position: relative;
  margin: 34px 0 0;
  padding: 0 0 0 4px;
  list-style: none;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 12px;
  bottom: 12px;
  width: 1px;
  background: rgba(10, 12, 16, 0.22);
}

.page-about .about-timeline__item {
  position: relative;
  display: grid;
  grid-template-columns: 26px minmax(0, 1fr);
  gap: 16px;
  padding: 14px 0 20px;
  outline: none;
}

.page-about .about-timeline__dot {
  position: relative;
  z-index: 1;
  align-self: start;
  margin-top: 6px;
  width: 11px;
  height: 11px;
  border: 2px solid rgba(10, 12, 16, 0.4);
  background: var(--cs-ivory);
  transition: background-color var(--cs-t), border-color var(--cs-t), transform var(--cs-t);
}

.page-about .about-timeline__item:hover .about-timeline__dot,
.page-about .about-timeline__item:focus-within .about-timeline__dot,
.page-about .about-timeline__item--now .about-timeline__dot {
  border-color: var(--cs-gold);
  background: var(--cs-gold);
  transform: scale(1.18);
}

.page-about .about-timeline__code {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--cs-green);
}

.page-about .about-timeline__item--now .about-timeline__code {
  color: #a3750a;
}

.page-about .about-timeline__title {
  margin: 8px 0 0;
  font-family: var(--cs-font-editorial);
  font-weight: 700;
  font-size: clamp(18px, 2.2vw, 24px);
  line-height: 1.4;
  color: var(--cs-ink);
}

.page-about .about-timeline__text {
  margin: 8px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: rgba(10, 12, 16, 0.7);
}

.page-about .about-timeline__note {
  margin: 0;
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  font-size: 13px;
  line-height: 1.7;
  color: #8a6a0f;
  transition: max-height 260ms ease, opacity 220ms ease, margin-top 260ms ease;
}

.page-about .about-timeline__item:hover .about-timeline__note,
.page-about .about-timeline__item:focus-within .about-timeline__note {
  max-height: 110px;
  opacity: 1;
  margin-top: 8px;
}

/* ---------- 准则 ---------- */
.page-about .about-rules {
  margin: 28px 0 0;
  display: grid;
  gap: 1px;
  background: var(--cs-line);
  border-top: 1px solid var(--cs-line);
  border-bottom: 1px solid var(--cs-line);
}

.page-about .about-rules__row {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 6px;
  padding: 18px 0;
  background: var(--cs-navy);
}

.page-about .about-rules__term {
  font-family: var(--cs-font-body);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.02em;
  color: var(--cs-gold);
}

.page-about .about-rules__desc {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(245, 242, 234, 0.78);
}

/* ---------- 合作 ---------- */
.page-about .about-partners {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 3vw, 40px);
  margin-top: 24px;
}

.page-about .about-partners__panel {
  padding: 24px 22px;
  border: 1px solid rgba(10, 12, 16, 0.16);
  border-top: 3px solid var(--cs-green);
  background: rgba(255, 255, 255, 0.5);
}

.page-about .about-partners__title {
  margin: 0 0 16px;
  font-family: var(--cs-font-display);
  font-weight: 900;
  font-size: 16px;
  letter-spacing: 0.02em;
  color: var(--cs-ink);
}

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

.page-about .about-partners__list li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 10px 0;
  border-bottom: 1px solid rgba(10, 12, 16, 0.12);
  font-size: 14px;
  line-height: 1.6;
  color: rgba(10, 12, 16, 0.78);
}

.page-about .about-partners__list li .cs-mono {
  min-width: 1.6em;
  font-size: 20px;
  font-weight: 700;
  color: var(--cs-green);
}

.page-about .about-partners__note {
  margin: 16px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: rgba(10, 12, 16, 0.6);
}

.page-about .about-partners__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 20px;
}

.page-about .about-sec--ivory .cs-btn--ghost {
  border-color: rgba(10, 12, 16, 0.3);
  color: var(--cs-ink);
}

.page-about .about-sec--ivory .cs-btn--ghost:hover {
  border-color: var(--cs-gold);
  color: #8a6a0f;
}

/* ---------- 收尾 ---------- */
.page-about .about-close__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

/* ---------- 渐变进入 ---------- */
.page-about .about-sec {
  opacity: 1;
}

html[data-anim="on"] .page-about .about-sec[data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 420ms ease, transform 420ms ease;
}

html[data-anim="on"] .page-about .about-sec[data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- 平板及以上 ---------- */
@media (min-width: 720px) {
  .page-about .about-origin {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: start;
  }

  .page-about .about-team {
    grid-template-columns: minmax(0, 260px) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-rules__row {
    grid-template-columns: minmax(0, 150px) minmax(0, 1fr);
    gap: 22px;
    align-items: baseline;
  }

  .page-about .about-partners {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    align-items: start;
  }
}

/* ---------- 桌面端双栏轨道 ---------- */
@media (min-width: 1024px) {
  .page-about .about-rail {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    column-gap: var(--about-gap);
    align-items: start;
  }

  .page-about .about-index {
    position: sticky;
    top: 108px;
  }

  .page-about .about-index__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    border-bottom: none;
    padding-bottom: 0;
  }

  .page-about .about-index__link {
    width: 100%;
    padding: 9px 0 9px 14px;
    border-bottom: none;
    border-left: 2px solid transparent;
    justify-content: flex-start;
  }

  .page-about .about-index__link:hover,
  .page-about .about-index__link:focus-visible,
  .page-about .about-index__link.is-active {
    border-bottom-color: transparent;
    border-left-color: var(--cs-gold);
    background: linear-gradient(90deg, rgba(212, 175, 55, 0.12), transparent 82%);
  }

  .page-about .about-index__num {
    font-size: 12px;
  }
}

@media (min-width: 1280px) {
  .page-about {
    --about-rail-w: 240px;
  }
}

/* ---------- 窄屏收敛 ---------- */
@media (max-width: 479px) {
  .page-about .about-hero__title {
    font-size: 30px;
  }

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

  .page-about .about-figures__num {
    font-size: 34px;
  }

  .page-about .about-timeline__item {
    grid-template-columns: 20px minmax(0, 1fr);
    gap: 12px;
  }

  .page-about .about-timeline::before {
    left: 2px;
  }

  .page-about .about-close__links .cs-btn {
    width: 100%;
    text-align: center;
  }
}

/* 触屏设备上时间轴说明常显 */
@media (hover: none) {
  .page-about .about-timeline__note {
    max-height: none;
    opacity: 1;
    margin-top: 8px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-timeline__note,
  .page-about .about-index__link,
  .page-about .about-timeline__dot {
    transition: none;
  }
}