.page-about {
  --about-rule: var(--line) solid var(--hair);
  --about-narrow: 46rem;
  padding-block: 1.5rem 3rem;
  color: var(--ink);
}

/* 面包屑下的首屏 */
.page-about .about-hero {
  position: relative;
  margin-top: 1rem;
  padding: 1.75rem 1.25rem 2.75rem;
  background: linear-gradient(135deg, var(--track-700) 0%, var(--abyss-900) 64%);
  border-top: var(--line) solid var(--signal-500);
  border-left: var(--about-rule);
  border-right: var(--about-rule);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 0 calc(100% - 26px));
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(
    0deg,
    rgba(195, 210, 220, 0.06) 0 1px,
    transparent 1px 6px
  );
  pointer-events: none;
}

.page-about .about-hero > * {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__eyebrow {
  margin: 0 0 0.9rem;
  font-size: 0.72rem;
  letter-spacing: 0.22em;
  color: var(--signal-500);
}

.page-about .about-hero__title {
  margin: 0 0 1rem;
  font-size: clamp(1.75rem, 7vw, 3.35rem);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--frost-50);
}

.page-about .about-hero__lead {
  margin: 0;
  max-width: 46rem;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--ink-dim);
}

.page-about .about-stats {
  list-style: none;
  margin: 1.75rem 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
}

.page-about .about-stat {
  padding: 0.75rem 0.9rem;
  background: rgba(6, 19, 33, 0.72);
  border: var(--about-rule);
  box-shadow: var(--shadow-drop);
}

.page-about .about-stat--lava {
  border-color: var(--lava-500);
  box-shadow: var(--shadow-lava);
}

.page-about .about-stat__num {
  display: block;
  font-size: 1.6rem;
  font-weight: 700;
  line-height: 1.1;
  color: var(--signal-500);
}

.page-about .about-stat--lava .about-stat__num {
  color: var(--lava-500);
}

.page-about .about-stat__unit {
  margin-left: 0.1em;
  font-size: 0.8em;
}

.page-about .about-stat__label {
  display: block;
  margin-top: 0.35rem;
  font-size: 0.8rem;
  color: var(--ink-faint);
}

/* 章节索引 */
.page-about .about-index {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.5rem;
  margin-top: 1.5rem;
}

.page-about .about-index__item {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  padding: 0.55rem 0.7rem;
  border: var(--about-rule);
  color: var(--ink-dim);
  font-size: 0.85rem;
  text-decoration: none;
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease),
    color var(--dur) var(--ease);
}

.page-about .about-index__item .mono {
  font-size: 0.74rem;
  color: var(--mist-500);
}

.page-about .about-index__item:hover,
.page-about .about-index__item:focus-visible {
  transform: translate(4px, -4px);
  border-color: var(--signal-500);
  color: var(--frost-50);
}

/* 章节通用 */
.page-about .about-chapter {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: var(--about-rule);
}

.page-about .about-chapter--narrow {
  max-width: var(--about-narrow);
}

.page-about .about-chapter .section-head {
  margin-bottom: 1.5rem;
}

/* 时间轴 */
.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 0 0 0 1.1rem;
  border-left: var(--line) solid rgba(31, 224, 207, 0.3);
}

.page-about .timeline__item {
  position: relative;
  padding-bottom: 0.9rem;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: calc(-1.1rem - 5px);
  top: 0.6rem;
  width: 8px;
  height: 8px;
  background: var(--signal-500);
  box-shadow: 0 0 0 3px rgba(31, 224, 207, 0.18);
}

.page-about .timeline__summary {
  display: flex;
  align-items: baseline;
  gap: 0.7rem;
  padding: 0.35rem 0;
  cursor: pointer;
  list-style: none;
}

.page-about .timeline__summary::-webkit-details-marker {
  display: none;
}

.page-about .timeline__summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  color: var(--signal-500);
}

.page-about .timeline__node[open] .timeline__summary::after {
  content: "−";
}

.page-about .timeline__year {
  font-size: 0.92rem;
  letter-spacing: 0.04em;
  color: var(--signal-500);
}

.page-about .timeline__name {
  font-size: 1rem;
  font-weight: 700;
  color: var(--frost-50);
}

.page-about .timeline__body {
  padding: 0.2rem 0 0.4rem;
}

.page-about .timeline__body p {
  margin: 0;
  max-width: 44rem;
  font-size: 0.95rem;
  line-height: 1.85;
  color: var(--ink-dim);
}

/* 四道工序 */
.page-about .process {
  display: grid;
  gap: 1.5rem;
}

.page-about .process__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.75rem;
}

.page-about .process__step {
  position: relative;
  padding: 1rem 1rem 1.1rem 3.2rem;
  background: rgba(13, 39, 64, 0.55);
  border: var(--about-rule);
  box-shadow: var(--shadow-drop);
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .process__step:hover {
  transform: translate(4px, -4px);
  border-color: var(--signal-500);
}

.page-about .process__idx {
  position: absolute;
  left: 0.95rem;
  top: 1rem;
  font-size: 0.8rem;
  color: var(--lava-500);
}

.page-about .process__name {
  margin: 0 0 0.35rem;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--frost-50);
}

.page-about .process__step p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--ink-dim);
}

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

.page-about .process__figure .media-frame,
.page-about .local-figure .media-frame,
.page-about .league-figure .media-frame {
  border: var(--about-rule);
  box-shadow: var(--shadow-hard);
}

.page-about .media-frame img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
}

/* 联赛地图 */
.page-about .league-layout {
  display: grid;
  gap: 1.5rem;
}

.page-about .league-map {
  min-width: 0;
}

.page-about .league-anchor {
  display: block;
  height: 0;
  scroll-margin-top: 5.5rem;
}

.page-about .league-switch {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.25rem;
}

.page-about .league-svg {
  display: block;
  width: 100%;
  max-width: 400px;
  height: auto;
}

.page-about .league-svg circle {
  opacity: 0.92;
  transition: opacity var(--dur) var(--ease);
}

.page-about .league-svg .dot--football {
  fill: var(--signal-500);
}

.page-about .league-svg .dot--basketball {
  fill: var(--lava-500);
}

.page-about .league-svg .dot--esports {
  fill: var(--condense-300);
}

.page-about .league-svg .dot--other {
  fill: var(--metal-400);
}

/* 纯前端类目高亮：点击标签后其余分组退到背景 */
.page-about #league-football:target ~ .league-svg .dot--basketball,
.page-about #league-football:target ~ .league-svg .dot--esports,
.page-about #league-football:target ~ .league-svg .dot--other {
  opacity: 0.14;
}

.page-about #league-basketball:target ~ .league-svg .dot--football,
.page-about #league-basketball:target ~ .league-svg .dot--esports,
.page-about #league-basketball:target ~ .league-svg .dot--other {
  opacity: 0.14;
}

.page-about #league-esports:target ~ .league-svg .dot--football,
.page-about #league-esports:target ~ .league-svg .dot--basketball,
.page-about #league-esports:target ~ .league-svg .dot--other {
  opacity: 0.14;
}

.page-about .league-caption {
  margin: 0.75rem 0 0;
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--ink-faint);
}

.page-about .league-note {
  margin: 1rem 0 0;
  padding-left: 1rem;
  border-left: var(--line) solid var(--lava-500);
  font-size: 0.9rem;
  line-height: 1.85;
  color: var(--ink-dim);
}

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

/* 本地服务 */
.page-about .local-figure {
  margin: 0;
}

.page-about .local-grid {
  display: grid;
  gap: 1rem;
  margin-top: 1.5rem;
}

.page-about .local-cell {
  padding: 0.35rem 0 0.35rem 1rem;
  border-left: var(--line) solid var(--signal-500);
}

.page-about .local-cell h3 {
  margin: 0 0 0.35rem;
  font-size: 1rem;
  font-weight: 700;
  color: var(--frost-50);
}

.page-about .local-cell p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--ink-dim);
}

/* 合作生态 */
.page-about .partner-wrap {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .partner-table {
  width: 100%;
  min-width: 34rem;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.page-about .partner-table th,
.page-about .partner-table td {
  padding: 0.8rem 0.9rem;
  text-align: left;
  vertical-align: top;
  border: var(--about-rule);
}

.page-about .partner-table thead th {
  background: rgba(13, 39, 64, 0.85);
  color: var(--signal-500);
  font-size: 0.76rem;
  letter-spacing: 0.12em;
}

.page-about .partner-table tbody th {
  color: var(--frost-50);
  font-weight: 700;
}

.page-about .partner-table td {
  color: var(--ink-dim);
  line-height: 1.75;
}

.page-about .partner-num {
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--lava-500);
  white-space: nowrap;
}

/* 团队构成 */
.page-about .team-bar {
  display: flex;
  flex-direction: column;
  border: var(--about-rule);
  margin-bottom: 1.5rem;
}

.page-about .team-bar__seg {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  padding: 0.9rem 1rem;
}

.page-about .team-bar__seg--data {
  flex: 24 1 0;
  background: var(--signal-500);
  color: var(--abyss-900);
}

.page-about .team-bar__seg--editor {
  flex: 9 1 0;
  background: var(--lava-500);
  color: var(--abyss-900);
}

.page-about .team-bar__seg--ops {
  flex: 35 1 0;
  background: rgba(13, 39, 64, 0.9);
  color: var(--ink-dim);
}

.page-about .team-bar__seg + .team-bar__seg {
  border-top: var(--line) solid var(--abyss-900);
}

.page-about .team-bar__num {
  font-size: 1.45rem;
  font-weight: 700;
  line-height: 1;
}

.page-about .team-bar__label {
  font-size: 0.85rem;
}

.page-about .team-note {
  margin: 0;
  max-width: 46rem;
  font-size: 0.92rem;
  line-height: 1.85;
  color: var(--ink-dim);
}

/* 后续入口 */
.page-about .about-next {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: var(--about-rule);
}

.page-about .about-next__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.9rem;
  margin-top: 1.5rem;
}

.page-about .about-next__card {
  display: block;
  padding: 1.1rem;
  text-decoration: none;
}

.page-about .about-next__card h3 {
  margin: 0 0 0.4rem;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--frost-50);
}

.page-about .about-next__card p {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.75;
  color: var(--ink-dim);
}

.page-about .about-next__more {
  display: inline-block;
  margin-top: 0.75rem;
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  color: var(--signal-500);
}

.page-about .about-next__tail {
  margin: 1.5rem 0 0;
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--ink-dim);
}

.page-about .about-next__tail a {
  color: var(--condense-300);
}

/* 响应式 */
@media (min-width: 640px) {
  .page-about .about-hero {
    padding: 2.5rem 2rem 3.5rem;
  }

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

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

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

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

@media (min-width: 900px) {
  .page-about .process {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    align-items: start;
    gap: 2rem;
  }

  .page-about .league-layout {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 0.65fr);
    align-items: start;
    gap: 2rem;
  }

  .page-about .team-bar {
    flex-direction: row;
  }

  .page-about .team-bar__seg + .team-bar__seg {
    border-top: 0;
    border-left: var(--line) solid var(--abyss-900);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__item,
  .page-about .process__step,
  .page-about .league-svg circle {
    transition: none;
  }

  .page-about .about-index__item:hover,
  .page-about .about-index__item:focus-visible,
  .page-about .process__step:hover {
    transform: none;
  }
}