.page-about {
  --about-rail: 44px;
  --about-gap: clamp(24px, 3vw, 48px);
  --about-panel: rgba(18, 63, 52, 0.55);
  --about-cell: #123F34;
  background: var(--ink-950);
  color: var(--text);
}

.page-about img {
  display: block;
  max-width: 100%;
  height: auto;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding-block: clamp(18px, 3vw, 34px) clamp(36px, 6vw, 76px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background:
    linear-gradient(118deg, rgba(43, 245, 200, 0.13) 0%, rgba(43, 245, 200, 0) 58%),
    linear-gradient(300deg, rgba(255, 106, 31, 0.14) 0%, rgba(255, 106, 31, 0) 44%);
  clip-path: polygon(48% 0, 100% 0, 100% 100%, 24% 100%);
}

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

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(18px, 3vw, 36px);
  padding-top: clamp(22px, 4vw, 52px);
}

.page-about .about-hero__title {
  margin: 10px 0 0;
  font-size: clamp(34px, 7.4vw, 84px);
  font-weight: 900;
  line-height: 1.02;
  letter-spacing: -0.02em;
  color: var(--text);
}

.page-about .about-hero__lede {
  margin: 0;
  max-width: 44ch;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: clamp(18px, 2.5vw, 28px);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(118px, 1fr));
  gap: 1px;
  margin: clamp(28px, 4vw, 52px) 0 0;
  padding: 0;
  background: var(--line-soft);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .about-facts__item {
  margin: 0;
  padding: 14px 12px 16px;
  background: var(--ink-950);
}

.page-about .about-facts dt {
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.page-about .about-facts dd {
  margin: 10px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(24px, 3.2vw, 34px);
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-facts__unit {
  margin-left: 4px;
  font-size: 12px;
  color: var(--muted);
}

/* ---------- 长卷骨架 ---------- */

.page-about .about-ledger {
  display: block;
  padding-bottom: clamp(40px, 6vw, 80px);
}

.page-about .about-rail {
  position: sticky;
  top: 0;
  z-index: 4;
  margin-bottom: clamp(20px, 3vw, 36px);
  background: var(--ink-950);
  border-bottom: 1px solid var(--line);
  padding-bottom: 6px;
}

.page-about .about-rail__list {
  display: flex;
  gap: 6px;
  margin: 0;
  padding: 4px 0;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-rail__list a {
  position: relative;
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 10px;
  border: 1px solid var(--line-soft);
  color: var(--muted);
  text-decoration: none;
  white-space: nowrap;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .about-rail__list a:hover,
.page-about .about-rail__list a:focus-visible {
  color: var(--cyan);
  border-color: var(--line-strong);
  background: rgba(43, 245, 200, 0.06);
}

.page-about .about-rail__num {
  font-size: 12px;
  color: var(--cyan);
}

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

/* ---------- 章节 ---------- */

.page-about .about-chapter {
  padding-block: clamp(34px, 5.5vw, 76px);
}

.page-about .about-chapter__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: clamp(10px, 2vw, 28px);
  align-items: start;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line);
}

.page-about .about-chapter__num {
  font-family: var(--font-mono);
  font-weight: 200;
  font-size: clamp(40px, 6vw, 88px);
  line-height: 0.8;
  letter-spacing: -0.02em;
  color: rgba(159, 247, 226, 0.16);
  -webkit-text-stroke: 1px var(--line-strong);
}

.page-about .about-chapter__head .h2 {
  margin: 6px 0 0;
}

.page-about .about-chapter__body {
  display: grid;
  gap: clamp(16px, 2vw, 24px);
  margin-top: clamp(18px, 3vw, 32px);
}

.page-about .about-chapter__body > p {
  margin: 0;
  max-width: 46ch;
  line-height: 1.8;
}

.page-about .about-chapter__body .lede {
  color: var(--muted);
}

.page-about .about-quote {
  margin: 6px 0 0;
  padding: 14px 0 14px 18px;
  border-left: 2px solid var(--signal);
  max-width: 44ch;
  color: var(--cyan-soft);
}

/* ---------- 时间线 ---------- */

.page-about .about-timeline__grid {
  display: grid;
  gap: clamp(20px, 3vw, 40px);
  margin-top: clamp(20px, 3vw, 34px);
}

.page-about .about-timeline__visual {
  margin: 0;
  border: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-timeline__visual img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.8) brightness(0.82);
}

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

.page-about .about-node {
  position: relative;
  padding: 0 0 clamp(20px, 3vw, 32px) clamp(22px, 3vw, 34px);
}

.page-about .about-node::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: -6px;
  width: 1px;
  background: linear-gradient(180deg, var(--line-strong), var(--line-soft));
}

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

.page-about .about-node__dot {
  position: absolute;
  left: 0;
  top: 7px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--signal);
  box-shadow: 0 0 0 4px rgba(255, 106, 31, 0.14);
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .about-node:hover .about-node__dot,
.page-about .about-node:focus-within .about-node__dot {
  transform: scale(1.45);
  box-shadow: 0 0 0 8px rgba(255, 106, 31, 0.22);
}

.page-about .about-node__stage {
  margin: 0 0 4px;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--cyan);
  transition: color var(--dur) var(--ease);
}

.page-about .about-node:hover .about-node__stage {
  color: var(--text);
}

.page-about .about-node .h3 {
  margin: 0 0 6px;
}

.page-about .about-node p {
  margin: 0;
  max-width: 44ch;
  color: var(--muted);
  line-height: 1.75;
}

/* ---------- 栏目分工 ---------- */

.page-about .about-nav-map {
  display: grid;
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--line-soft);
  border: 1px solid var(--line);
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 260px), 1fr));
}

.page-about .about-nav-map__item {
  padding: 18px 16px 20px;
  background: var(--about-cell);
  transition: background-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .about-nav-map__item:hover {
  background: #164A3D;
  box-shadow: inset 0 0 0 1px var(--line-strong);
}

.page-about .about-nav-map__item .h3 {
  margin: 0 0 8px;
  color: var(--cyan);
}

.page-about .about-nav-map__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .about-lanes {
  margin-top: clamp(22px, 3vw, 38px);
}

.page-about .about-lanes__title {
  margin: 0 0 14px;
}

.page-about .about-lanes__list {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-lane {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 4px 14px;
  padding: 14px 16px;
  border-left: 2px solid var(--cyan);
  background: var(--about-panel);
}

.page-about .about-lane__key {
  grid-row: span 2;
  align-self: start;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

.page-about .about-lane__name {
  margin: 0;
  font-weight: 700;
}

.page-about .about-lane__desc {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 团队 ---------- */

.page-about .about-team {
  display: grid;
  gap: clamp(20px, 3vw, 40px);
  margin-top: clamp(18px, 3vw, 32px);
}

.page-about .about-team__text > p {
  margin: 0 0 16px;
  max-width: 44ch;
  line-height: 1.8;
}

.page-about .about-team__grid {
  display: grid;
  gap: 1px;
  margin: 0 0 18px;
  padding: 0;
  list-style: none;
  background: var(--line-soft);
  border: 1px solid var(--line);
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 150px), 1fr));
}

.page-about .about-team__cell {
  padding: 16px 14px 18px;
  background: var(--about-cell);
}

.page-about .about-team__num {
  display: block;
  font-size: clamp(28px, 3.6vw, 40px);
  line-height: 1;
  color: var(--cyan-soft);
}

.page-about .about-team__cell .h3 {
  margin: 10px 0 6px;
  font-size: 16px;
}

.page-about .about-team__cell p {
  margin: 0;
  font-size: 13px;
  line-height: 1.65;
  color: var(--muted);
}

.page-about .about-team__visual {
  margin: 0;
  border: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-team__visual img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.75) brightness(0.85);
}

/* ---------- 赛事覆盖 ---------- */

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

.page-about .about-sport {
  display: flex;
  align-items: baseline;
  gap: 8px;
  border: 1px solid var(--line);
  background: rgba(18, 63, 52, 0.7);
  color: var(--text);
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .about-sport:hover {
  border-color: var(--cyan);
  background: rgba(43, 245, 200, 0.08);
  transform: translateY(-2px);
}

.page-about .about-sport__idx {
  font-size: 11px;
  color: var(--muted);
}

.page-about .about-sport--xl {
  padding: 16px 20px;
  font-size: 20px;
  font-weight: 700;
}

.page-about .about-sport--lg {
  padding: 13px 17px;
  font-size: 17px;
  font-weight: 600;
}

.page-about .about-sport--md {
  padding: 10px 14px;
  font-size: 15px;
  color: var(--cyan-soft);
}

.page-about .about-coverage__visual {
  margin: clamp(22px, 3vw, 38px) 0 0;
  border: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-coverage__visual img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.8) brightness(0.8);
}

/* ---------- 数据来源 ---------- */

.page-about .about-sources {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 240px), 1fr));
}

.page-about .about-source {
  padding: 16px;
  border-top: 2px solid var(--cyan);
  background: var(--about-panel);
}

.page-about .about-source__num {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

.page-about .about-source__name {
  margin: 8px 0 6px;
  font-weight: 700;
}

.page-about .about-source__desc {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 下一步 ---------- */

.page-about .about-next {
  display: grid;
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--line-soft);
  border: 1px solid var(--line);
  counter-reset: about-next;
}

.page-about .about-next__item {
  position: relative;
  padding: 18px 18px 20px 58px;
  background: var(--ink-950);
  counter-increment: about-next;
}

.page-about .about-next__item::before {
  content: "0" counter(about-next);
  position: absolute;
  left: 16px;
  top: 20px;
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--signal);
}

.page-about .about-next__item .h3 {
  margin: 0 0 6px;
}

.page-about .about-next__item p {
  margin: 0;
  max-width: 52ch;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 收束 ---------- */

.page-about .about-cta {
  margin-top: clamp(28px, 4vw, 56px);
  padding: clamp(24px, 4vw, 48px);
  border: 1px solid var(--line);
  border-left: 3px solid var(--signal);
  background:
    linear-gradient(120deg, rgba(255, 106, 31, 0.1) 0%, rgba(255, 106, 31, 0) 46%),
    var(--ink-800);
}

.page-about .about-cta__title {
  margin: 0 0 12px;
}

.page-about .about-cta__text {
  margin: 0;
  max-width: 48ch;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: clamp(18px, 2.5vw, 26px);
}

/* ---------- 响应式 ---------- */

@media (min-width: 720px) {
  .page-about .about-timeline__grid {
    grid-template-columns: minmax(0, 0.72fr) minmax(0, 1.28fr);
    align-items: start;
  }

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

  .page-about .about-team {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    align-items: start;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    align-items: end;
  }

  .page-about .about-hero__side {
    padding-bottom: 8px;
  }
}

@media (min-width: 1024px) {
  .page-about .about-ledger {
    display: grid;
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: var(--about-gap);
  }

  .page-about .about-rail {
    position: sticky;
    top: 108px;
    align-self: start;
    margin-bottom: 0;
    background: transparent;
    border-bottom: 0;
    padding-bottom: 0;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
  }

  .page-about .about-rail__list a {
    width: var(--about-rail);
    height: var(--about-rail);
    justify-content: center;
    gap: 0;
    padding: 0;
    border: 0;
    border-left: 1px solid var(--line);
    background: transparent;
  }

  .page-about .about-rail__list a:hover,
  .page-about .about-rail__list a:focus-visible {
    border-left-color: var(--cyan);
    background: rgba(43, 245, 200, 0.06);
  }

  .page-about .about-rail__name {
    position: absolute;
    left: calc(100% + 8px);
    top: 50%;
    transform: translateY(-50%) translateX(-4px);
    padding: 4px 8px;
    background: var(--ink-700);
    border: 1px solid var(--line);
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease);
  }

  .page-about .about-rail__list a:hover .about-rail__name,
  .page-about .about-rail__list a:focus-visible .about-rail__name {
    opacity: 1;
    transform: translateY(-50%) translateX(0);
  }

  .page-about .about-chapter {
    scroll-margin-top: 120px;
  }

  .page-about .about-cta {
    scroll-margin-top: 120px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-node__dot,
  .page-about .about-sport,
  .page-about .about-rail__name,
  .page-about .about-nav-map__item {
    transition: none;
  }

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