.page-about {
  --about-rail-w: 232px;
  --about-ease: cubic-bezier(.2, .7, .3, 1);
  --about-ink: #2C3A63;
  --about-glow: rgba(34, 230, 211, .16);
  padding-bottom: clamp(52px, 8vw, 104px);
}

/* 面包屑 */
.page-about .breadcrumbs {
  margin: clamp(18px, 3vw, 32px) 0 clamp(16px, 2.6vw, 26px);
  font-size: 13px;
  letter-spacing: .02em;
}

/* 首屏 */
.page-about .about-intro {
  position: relative;
  overflow: hidden;
  padding: clamp(22px, 3.4vw, 44px) clamp(18px, 3vw, 40px) clamp(26px, 3.6vw, 46px);
  border: 1px solid var(--line);
  border-radius: 3px;
  background:
    linear-gradient(138deg, rgba(34, 230, 211, .10), transparent 44%),
    linear-gradient(322deg, rgba(122, 92, 255, .17), transparent 58%),
    var(--panel);
}

.page-about .about-intro::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(44, 58, 99, .55) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(44, 58, 99, .55) 1px, transparent 1px);
  background-size: 52px 52px;
  opacity: .5;
  -webkit-mask-image: radial-gradient(120% 95% at 10% 0%, #000 10%, transparent 62%);
  mask-image: radial-gradient(120% 95% at 10% 0%, #000 10%, transparent 62%);
}

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

.page-about .about-intro__title {
  margin: 14px 0 0;
  max-width: 18em;
  font-family: var(--font-display);
  font-size: clamp(27px, 4.2vw, 50px);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -.02em;
  color: var(--text);
}

.page-about .about-intro__lede {
  margin: 18px 0 0;
  max-width: 62ch;
  font-size: clamp(15px, 1.15vw, 17px);
  line-height: 1.82;
  color: var(--muted);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(24px, 3.4vw, 36px) 0 0;
  padding: 0;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 2px;
  overflow: hidden;
}

.page-about .about-facts__cell {
  padding: 14px 16px;
  background: var(--panel-deep);
}

.page-about .about-facts dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-facts dd {
  margin: 6px 0 0;
  font-family: var(--font-display);
  font-size: clamp(20px, 2.4vw, 28px);
  font-weight: 800;
  letter-spacing: -.01em;
  color: var(--cyan);
}

/* 左侧时间线轨道 + 内容区 */
.page-about .about-split {
  margin-top: clamp(32px, 4.6vw, 64px);
}

.page-about .about-rail {
  margin-bottom: clamp(26px, 4vw, 40px);
}

.page-about .about-rail__list {
  position: relative;
  display: flex;
  gap: 10px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .about-rail__item {
  transition: opacity 420ms var(--about-ease);
}

.page-about .about-rail__item:nth-child(1) { transition-delay: 0ms; }
.page-about .about-rail__item:nth-child(2) { transition-delay: 80ms; }
.page-about .about-rail__item:nth-child(3) { transition-delay: 160ms; }
.page-about .about-rail__item:nth-child(4) { transition-delay: 240ms; }
.page-about .about-rail__item:nth-child(5) { transition-delay: 320ms; }
.page-about .about-rail__item:nth-child(6) { transition-delay: 400ms; }

.page-about .about-rail__link {
  position: relative;
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 9px 13px;
  border: 1px solid var(--line);
  border-radius: 2px;
  background: var(--panel);
  color: var(--muted);
  font-size: 13px;
  text-decoration: none;
  white-space: nowrap;
  transition: color 220ms var(--about-ease), border-color 220ms var(--about-ease), background 220ms var(--about-ease);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--text);
  border-color: var(--cyan);
  background: var(--surface);
  outline: none;
}

.page-about .about-rail__num {
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--cyan);
}

.page-about .about-rail__dot {
  display: none;
}

/* 章节 */
.page-about .about-section {
  padding: clamp(28px, 4vw, 48px) 0;
  border-top: 1px solid var(--line);
}

.page-about .about-flow > .about-section:first-child {
  padding-top: 0;
  border-top: 0;
}

.page-about .about-section__title {
  margin: 10px 0 0;
  max-width: 24em;
  font-family: var(--font-display);
  font-size: clamp(22px, 2.8vw, 32px);
  font-weight: 800;
  line-height: 1.24;
  letter-spacing: -.015em;
  color: var(--text);
}

.page-about .about-section__lede {
  margin: 14px 0 0;
  max-width: 64ch;
  font-size: 15.5px;
  line-height: 1.82;
  color: var(--muted);
}

/* 图片 */
.page-about .about-figure {
  margin: clamp(20px, 3vw, 30px) 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: 2px;
}

.page-about .about-figure--wide img {
  aspect-ratio: 8 / 3;
}

.page-about .about-figure .media__caption {
  margin-top: 10px;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--muted);
}

/* 版本列表 */
.page-about .about-versions {
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 14px;
}

.page-about .about-version {
  position: relative;
  padding: 18px 20px 18px 26px;
  border: 1px solid var(--line);
  border-radius: 2px;
  background: linear-gradient(180deg, var(--surface), var(--panel));
  transition: border-color 220ms var(--about-ease);
}

.page-about .about-version::before {
  content: "";
  position: absolute;
  left: -1px;
  top: -1px;
  bottom: -1px;
  width: 3px;
  border-radius: 2px 0 0 2px;
  background: linear-gradient(180deg, var(--cyan), var(--purple));
}

.page-about .about-version:hover {
  border-color: rgba(34, 230, 211, .45);
}

.page-about .about-version__head {
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.page-about .about-version__code {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--cyan);
}

.page-about .about-version__era {
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--muted);
}

.page-about .about-version__title {
  margin: 8px 0 0;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 800;
  color: var(--text);
}

.page-about .about-version__text {
  margin: 8px 0 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.76;
  color: var(--muted);
}

.page-about .about-version__text a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(34, 230, 211, .4);
}

.page-about .about-version__text a:hover {
  border-bottom-color: var(--cyan);
}

/* 团队角色卡 */
.page-about .about-roles {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--gap);
  margin-top: clamp(22px, 3vw, 32px);
}

.page-about .about-role {
  border: 1px solid var(--line);
  border-radius: 2px;
  background: var(--panel);
  transition: border-color 220ms var(--about-ease), background 220ms var(--about-ease);
}

.page-about .about-role:hover {
  border-color: rgba(34, 230, 211, .4);
  background: var(--surface);
}

.page-about .about-role__trigger {
  position: relative;
  display: flex;
  align-items: center;
  gap: 12px;
  width: 100%;
  padding: 18px 92px 18px 18px;
  border: 0;
  background: none;
  color: inherit;
  text-align: left;
  cursor: pointer;
  font: inherit;
}

.page-about .about-role__trigger:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: -2px;
}

.page-about .about-role__count {
  min-width: 2.4ch;
  font-size: clamp(26px, 3.2vw, 36px);
  font-weight: 700;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-role__name {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 800;
  color: var(--text);
}

.page-about .about-role__code {
  position: absolute;
  right: 14px;
  bottom: 14px;
  padding: 3px 6px;
  border: 1px solid var(--line);
  border-radius: 2px;
  font-size: 10px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-role__body ul {
  margin: 0;
  padding-left: 18px;
  display: grid;
  gap: 8px;
}

.page-about .about-role__body li {
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--muted);
}

.page-about .about-role__body li::marker {
  color: var(--cyan);
}

/* 数据表 */
.page-about .about-datagrid {
  margin: clamp(20px, 3vw, 30px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 2px;
  overflow: hidden;
}

.page-about .about-datagrid .datagrid__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding: 13px 16px;
  background: var(--panel);
}

.page-about .about-datagrid .datagrid__key {
  font-size: 14px;
  color: var(--muted);
}

.page-about .about-datagrid .datagrid__val {
  font-size: 15px;
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--text);
  text-align: right;
}

/* 服务坐标 */
.page-about .about-coord {
  position: relative;
  overflow: hidden;
  margin-top: clamp(20px, 3vw, 30px);
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 2px;
  background: var(--panel-deep);
}

.page-about .about-coord__grid {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(44, 58, 99, .6) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(44, 58, 99, .6) 1px, transparent 1px);
  background-size: 34px 34px;
  opacity: .55;
  -webkit-mask-image: radial-gradient(120% 110% at 50% 0%, #000 20%, transparent 78%);
  mask-image: radial-gradient(120% 110% at 50% 0%, #000 20%, transparent 78%);
}

.page-about .about-coord__label {
  position: relative;
  z-index: 1;
  margin: 0;
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-coord__list {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
  margin: 14px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-coord__item {
  position: relative;
  padding: 12px 14px 12px 34px;
  border: 1px solid var(--line);
  border-radius: 2px;
  background: rgba(27, 37, 71, .74);
}

.page-about .about-coord__item--base {
  border-color: rgba(34, 230, 211, .5);
  background: rgba(34, 230, 211, .07);
}

.page-about .about-coord__pin {
  position: absolute;
  left: 14px;
  top: 18px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  border: 2px solid var(--cyan);
  background: var(--bg);
}

.page-about .about-coord__item--base .about-coord__pin {
  background: var(--cyan);
  box-shadow: 0 0 0 5px var(--about-glow);
}

.page-about .about-coord__name {
  display: block;
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 700;
  color: var(--text);
}

.page-about .about-coord__desc {
  display: block;
  margin-top: 4px;
  font-size: 13px;
  color: var(--muted);
}

/* 联系方式 */
.page-about .about-contact {
  margin: clamp(20px, 3vw, 28px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 2px;
  overflow: hidden;
}

.page-about .about-contact__row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 6px;
  padding: 13px 16px;
  background: var(--panel);
}

.page-about .about-contact__key {
  font-size: 11px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-contact__val {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.6;
  color: var(--text);
  word-break: break-word;
}

.page-about .about-contact__note {
  margin: 12px 0 0;
  max-width: 64ch;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .about-contact__note a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(34, 230, 211, .4);
}

.page-about .about-contact__note a:hover {
  border-bottom-color: var(--cyan);
}

/* 球迷组织流程 */
.page-about .about-club {
  margin-top: clamp(22px, 3vw, 30px);
  padding: clamp(18px, 2.6vw, 26px);
  border: 1px solid var(--line);
  border-radius: 2px;
  background: linear-gradient(160deg, rgba(122, 92, 255, .12), transparent 62%), var(--panel);
}

.page-about .about-club__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 800;
  color: var(--text);
}

.page-about .about-club__list {
  margin: 16px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 12px;
}

.page-about .about-club__list > li {
  display: grid;
  grid-template-columns: 1fr;
  gap: 5px;
  padding-left: 14px;
  border-left: 2px solid var(--about-ink);
  transition: border-color 220ms var(--about-ease);
}

.page-about .about-club__list > li:hover {
  border-left-color: var(--cyan);
}

.page-about .about-club__step {
  font-size: 10.5px;
  letter-spacing: .16em;
  color: var(--purple);
}

.page-about .about-club__text {
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--muted);
}

/* 合作折叠条目 */
.page-about .about-partners {
  display: grid;
  gap: 12px;
  margin-top: clamp(22px, 3vw, 30px);
}

.page-about .about-partner {
  border: 1px solid var(--line);
  border-radius: 2px;
  background: var(--panel);
  transition: border-color 220ms var(--about-ease);
}

.page-about .about-partner:hover {
  border-color: rgba(122, 92, 255, .5);
}

.page-about .about-partner__trigger {
  display: flex;
  align-items: center;
  gap: 14px;
  width: 100%;
  padding: 15px 16px;
  border: 0;
  background: none;
  color: inherit;
  text-align: left;
  cursor: pointer;
  font: inherit;
}

.page-about .about-partner__trigger:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: -2px;
}

.page-about .about-partner__tag {
  flex: 0 0 auto;
}

.page-about .about-partner__name {
  flex: 1 1 auto;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  color: var(--text);
}

.page-about .about-partner__sign {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 18px;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-partner .disclosure__body p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--muted);
}

/* 结尾 */
.page-about .about-next {
  margin-top: clamp(30px, 4.4vw, 56px);
  padding: clamp(22px, 3.2vw, 38px);
  border: 1px solid var(--line);
  border-radius: 3px;
  background:
    linear-gradient(120deg, rgba(34, 230, 211, .12), transparent 46%),
    linear-gradient(300deg, rgba(122, 92, 255, .18), transparent 58%),
    var(--panel-deep);
}

.page-about .about-next__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(20px, 2.4vw, 26px);
  font-weight: 800;
  letter-spacing: -.01em;
  color: var(--text);
}

.page-about .about-next__text {
  margin: 12px 0 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-next__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 20px;
}

/* 平板及以上 */
@media (min-width: 720px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

  .page-about .about-contact__row {
    grid-template-columns: 140px minmax(0, 1fr);
    align-items: baseline;
    gap: 16px;
  }
}

/* 桌面：左轨固定 + 右侧内容 */
@media (min-width: 940px) {
  .page-about .about-split {
    display: grid;
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: clamp(30px, 4.2vw, 68px);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--brandbar-h) + 24px);
    margin-bottom: 0;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    gap: 0;
    padding: 6px 0 6px 26px;
    overflow: visible;
  }

  .page-about .about-rail__list::before {
    content: "";
    position: absolute;
    left: 6px;
    top: 14px;
    bottom: 14px;
    width: 2px;
    border-radius: 2px;
    background: linear-gradient(180deg, var(--cyan), var(--purple));
  }

  .page-about .about-rail__link {
    width: 100%;
    padding: 11px 0;
    border: 0;
    border-radius: 0;
    background: none;
    white-space: normal;
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    background: none;
    border-color: transparent;
    color: var(--text);
  }

  .page-about .about-rail__dot {
    display: block;
    position: absolute;
    left: -25px;
    top: 50%;
    width: 12px;
    height: 12px;
    margin-top: -6px;
    border-radius: 50%;
    border: 2px solid var(--about-ink);
    background: var(--bg);
    transition: border-color 260ms var(--about-ease), background 260ms var(--about-ease), box-shadow 260ms var(--about-ease);
  }

  .page-about .about-rail__link:hover .about-rail__dot,
  .page-about .about-rail__link:focus-visible .about-rail__dot {
    border-color: var(--cyan);
    background: var(--cyan);
    box-shadow: 0 0 0 5px var(--about-glow);
  }

  .page-about .about-versions {
    gap: 16px;
  }
}

/* 动效降级 */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__item,
  .page-about .about-rail__link,
  .page-about .about-rail__dot,
  .page-about .about-version,
  .page-about .about-role,
  .page-about .about-partner,
  .page-about .about-club__list > li {
    transition: none !important;
  }
}