.page-about {
  --about-rail: 34px;
  --about-rail-lg: 118px;
}

/* ---------- 首屏框景 ---------- */
.page-about .about-hero {
  padding-block: clamp(26px, 5vw, 64px) clamp(18px, 3vw, 34px);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 52px);
  align-items: end;
}

.page-about .about-hero__frame {
  position: relative;
  padding: clamp(20px, 3vw, 38px);
  border: 1px solid var(--line);
  background: linear-gradient(155deg, rgba(22, 39, 63, 0.62), rgba(7, 12, 24, 0) 66%);
}

.page-about .about-hero__frame::before {
  content: "";
  position: absolute;
  top: 8px;
  right: 8px;
  width: 58px;
  height: 58px;
  border-top: 1px solid var(--lime);
  border-right: 1px solid var(--lime);
  pointer-events: none;
}

.page-about .about-hero__title {
  margin: 12px 0 0;
  font-size: clamp(2rem, 5.6vw, 3.5rem);
  line-height: 1.1;
  font-weight: 900;
  letter-spacing: 0.01em;
  color: var(--white);
}

.page-about .about-hero__lede {
  margin-top: 18px;
  max-width: 46ch;
  color: var(--mist);
}

.page-about .about-hero__note {
  margin-top: 22px;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--gray);
  text-transform: uppercase;
}

.page-about .about-hero__figure {
  margin: 0;
  position: relative;
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 14 / 9;
  object-fit: cover;
  border: 1px solid var(--line);
}

.page-about .about-hero__figure::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(90deg, var(--line-soft) 1px, transparent 1px),
    linear-gradient(180deg, var(--line-soft) 1px, transparent 1px);
  background-size: 72px 72px;
  pointer-events: none;
  opacity: 0.7;
}

.page-about .about-hero__caption {
  margin-top: 12px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--gray);
  max-width: 52ch;
}

.page-about .about-hero .tick-rule {
  margin-top: clamp(24px, 4vw, 44px);
}

/* ---------- 章节目录 ---------- */
.page-about .about-toc {
  margin-block: clamp(18px, 3vw, 34px) clamp(30px, 5vw, 58px);
  padding-block: 12px;
  border-top: 1px solid var(--line-soft);
  border-bottom: 1px solid var(--line-soft);
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-toc .toc {
  display: flex;
  gap: 26px;
  min-width: max-content;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-toc .toc__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  white-space: nowrap;
  font-size: 14px;
  color: var(--mist);
  text-decoration: none;
}

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

.page-about .about-toc .toc__link:hover,
.page-about .about-toc .toc__link[aria-current="true"] {
  color: var(--lime);
}

/* ---------- 编年长卷 ---------- */
.page-about .chronicle__list {
  position: relative;
  margin: 0;
  padding: 6px 0 0;
  list-style: none;
}

.page-about .chronicle__list::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 12px;
  bottom: 12px;
  width: 2px;
  background: linear-gradient(
    180deg,
    var(--lime) 0%,
    var(--cyan) 38%,
    var(--orange) 72%,
    rgba(140, 153, 171, 0.16) 100%
  );
  opacity: 0.75;
}

.page-about .chronicle__item {
  position: relative;
  padding-left: var(--about-rail);
  padding-bottom: clamp(30px, 5vw, 54px);
}

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

.page-about .chronicle__dot {
  position: absolute;
  left: 0;
  top: 8px;
  width: 12px;
  height: 12px;
  border: 2px solid var(--gray);
  background: var(--ink);
  transition: border-color 0.2s ease, background-color 0.2s ease, transform 0.2s ease;
}

.page-about .chronicle__item:hover .chronicle__dot,
.page-about .chronicle__item:focus-within .chronicle__dot {
  border-color: var(--lime);
  background: var(--lime);
  transform: scale(1.3);
}

.page-about .chronicle__item--key .chronicle__dot {
  border-color: var(--orange);
}

.page-about .chronicle__top {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 14px;
}

.page-about .chronicle__season {
  font-size: clamp(1.25rem, 3vw, 1.75rem);
  letter-spacing: 0.06em;
  color: var(--mist);
  transition: color 0.2s ease;
}

.page-about .chronicle__item:hover .chronicle__season {
  color: var(--lime);
}

.page-about .chronicle__title {
  margin: 12px 0 0;
  font-size: clamp(1.15rem, 2.2vw, 1.5rem);
  line-height: 1.35;
  font-weight: 700;
  color: var(--white);
}

.page-about .chronicle__text {
  margin: 10px 0 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .chronicle__facts {
  margin: 14px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 6px;
  max-width: 62ch;
}

.page-about .chronicle__facts li {
  position: relative;
  padding-left: 16px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--gray);
}

.page-about .chronicle__facts li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 7px;
  height: 1px;
  background: var(--cyan);
}

/* ---------- 版本对照 ---------- */
.page-about .versions {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
}

.page-about .version {
  padding: 22px 20px;
  border: 1px solid var(--line);
  background: rgba(14, 26, 46, 0.5);
}

.page-about .version--current {
  border-color: rgba(182, 255, 60, 0.42);
  background: linear-gradient(180deg, rgba(182, 255, 60, 0.08), rgba(7, 12, 24, 0.2) 62%);
}

.page-about .version__head {
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .version__mark {
  display: block;
  font-size: 13px;
  letter-spacing: 0.2em;
  color: var(--lime);
}

.page-about .version--current .version__mark {
  color: var(--orange);
}

.page-about .version__name {
  margin: 8px 0 0;
  font-size: clamp(1.2rem, 2.3vw, 1.55rem);
  font-weight: 800;
  color: var(--white);
}

.page-about .version__span {
  margin: 6px 0 0;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--gray);
}

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

.page-about .version__row {
  padding: 14px 0;
  border-bottom: 1px dashed var(--line-soft);
}

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

.page-about .version__term {
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--cyan);
  text-transform: uppercase;
}

.page-about .version__desc {
  margin: 8px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 净胜球口径 ---------- */
.page-about .diff-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 46px);
  align-items: start;
}

.page-about .diff-formula {
  margin: 0;
  padding: 18px 20px;
  border-left: 3px solid var(--lime);
  background: rgba(22, 39, 63, 0.55);
  font-size: clamp(1.05rem, 2.4vw, 1.5rem);
  letter-spacing: 0.02em;
  color: var(--white);
}

.page-about .diff-formula__note {
  margin: 10px 0 0;
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--orange);
}

.page-about .diff-text p {
  margin-top: 18px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--mist);
  max-width: 58ch;
}

.page-about .diff-link {
  color: var(--gray);
}

.page-about .diff-figure {
  margin: 0;
}

.page-about .diff-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  border: 1px solid var(--line);
}

.page-about .diff-figure__caption {
  margin-top: 12px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--gray);
}

/* ---------- 团队与流程 ---------- */
.page-about .team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 46px);
  align-items: start;
}

.page-about .team-text p {
  margin: 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--mist);
  max-width: 58ch;
}

.page-about .roles {
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .roles__item {
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 4px 16px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .roles__num {
  grid-row: span 2;
  align-self: start;
  font-size: 1.5rem;
  line-height: 1.1;
  color: var(--lime);
  letter-spacing: 0.04em;
}

.page-about .roles__name {
  font-size: 16px;
  font-weight: 700;
  color: var(--white);
}

.page-about .roles__desc {
  font-size: 13px;
  line-height: 1.7;
  color: var(--gray);
}

.page-about .process {
  margin-top: 26px;
  padding: 20px 22px;
  border: 1px solid var(--line);
  background: linear-gradient(160deg, rgba(53, 208, 208, 0.07), rgba(7, 12, 24, 0) 60%);
}

.page-about .process__title {
  margin: 0 0 12px;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--white);
}

.page-about .process p {
  margin-top: 10px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .process__key {
  color: var(--cyan);
  font-weight: 700;
  margin-right: 4px;
}

.page-about .team-figure {
  margin: 0;
}

.page-about .team-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  border: 1px solid var(--line);
}

.page-about .team-figure__caption {
  margin-top: 12px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--gray);
}

/* ---------- 数据来源 ---------- */
.page-about .sources-panel {
  padding: clamp(20px, 3vw, 32px);
}

.page-about .sources-panel p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--mist);
}

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

.page-about .sources-panel strong {
  color: var(--lime);
  font-size: 1.1em;
}

.page-about .aside-num {
  margin: 10px 0 0;
  font-size: 1.5rem;
  letter-spacing: 0.03em;
  color: var(--white);
}

.page-about .aside-unit {
  margin-left: 8px;
  font-family: var(--sans);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--gray);
}

.page-about .aside-link {
  margin-top: 20px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--gray);
}

/* ---------- 勘误流程 ---------- */
.page-about .flow {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}

.page-about .flow__step {
  padding: 22px 20px;
  background: var(--ink);
}

.page-about .flow__num {
  display: block;
  font-size: 1.35rem;
  letter-spacing: 0.16em;
  color: var(--orange);
}

.page-about .flow__title {
  margin: 10px 0 0;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--white);
}

.page-about .flow__text {
  margin: 8px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .maintenance-tail {
  margin-top: 26px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--gray);
}

/* ---------- 文本链接统一微交互 ---------- */
.page-about .text-link {
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid rgba(182, 255, 60, 0.35);
  transition: border-color 0.2s ease, color 0.2s ease;
}

.page-about .text-link:hover {
  border-bottom-color: var(--lime);
  color: var(--white);
}

/* ---------- 平板 ---------- */
@media (min-width: 700px) {
  .page-about .flow {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

/* ---------- 桌面 ---------- */
@media (min-width: 960px) {
  .page-about {
    --about-rail: var(--about-rail-lg);
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }

  .page-about .chronicle__item {
    padding-bottom: clamp(38px, 5vw, 68px);
  }

  .page-about .chronicle__body {
    max-width: 74ch;
  }

  .page-about .versions {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr) minmax(0, 1.18fr);
    gap: 0;
    align-items: start;
    border-top: 1px solid var(--line-soft);
    padding-top: 8px;
  }

  .page-about .version {
    border: 0;
    border-left: 1px solid var(--line);
    background: none;
    padding: 26px 26px 30px;
  }

  .page-about .version:nth-child(1) {
    margin-top: 0;
  }

  .page-about .version:nth-child(2) {
    margin-top: 54px;
  }

  .page-about .version--current {
    margin-top: 26px;
    border-left-color: rgba(182, 255, 60, 0.5);
    background: linear-gradient(180deg, rgba(182, 255, 60, 0.08), rgba(7, 12, 24, 0) 58%);
  }

  .page-about .diff-grid {
    grid-template-columns: minmax(0, 1.42fr) minmax(0, 1fr);
  }

  .page-about .team-grid {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
  }

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

  .page-about .flow__step {
    padding: 26px 20px 30px;
  }
}

@media (min-width: 1180px) {
  .page-about .version {
    padding-inline: 30px;
  }

  .page-about .about-hero__frame {
    padding: 44px 42px;
  }
}

/* ---------- 降低动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .chronicle__dot,
  .page-about .chronicle__season,
  .page-about .text-link {
    transition: none;
  }
}