.page-about {
  --ab-rail: 200px;
  --ab-gap: 52px;
  display: block;
  background: var(--yb-ice);
  color: var(--yb-navy);
  font-family: var(--yb-body);
  font-size: 16px;
  line-height: 1.75;
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(circle at 84% 10%, rgba(31, 224, 210, .16), transparent 46%),
    radial-gradient(circle at 6% 92%, rgba(255, 159, 46, .10), transparent 42%),
    var(--yb-navy);
  color: var(--yb-ice);
  padding: clamp(24px, 4.2vw, 44px) 0 clamp(40px, 6vw, 72px);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(201, 220, 234, .06) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(201, 220, 234, .06) 1px, transparent 1px);
  background-size: 52px 52px;
  pointer-events: none;
}

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

/* 面包屑 */
.page-about .about-crumb {
  margin-bottom: clamp(22px, 3.4vw, 38px);
}

.page-about .about-crumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 13px;
  font-family: var(--yb-body);
}

.page-about .about-crumb li {
  display: flex;
  align-items: center;
  color: rgba(201, 220, 234, .62);
}

.page-about .about-crumb li + li::before {
  content: "/";
  padding: 0 8px;
  color: rgba(201, 220, 234, .34);
}

.page-about .about-crumb a {
  color: rgba(201, 220, 234, .78);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .18s ease, border-color .18s ease;
}

.page-about .about-crumb a:hover,
.page-about .about-crumb a:focus-visible {
  color: var(--yb-cyan);
  border-bottom-color: var(--yb-cyan);
  outline: none;
}

.page-about .about-hero__eyebrow {
  font-family: var(--yb-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--yb-cyan);
  margin: 0 0 14px;
}

.page-about .about-hero__title {
  font-family: var(--yb-display);
  font-weight: 900;
  font-size: clamp(30px, 5.2vw, 56px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin: 0 0 18px;
  max-width: min(100%, 880px);
  color: var(--yb-ice);
}

.page-about .about-hero__lead {
  max-width: 660px;
  margin: 0;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.85;
  color: rgba(244, 249, 253, .82);
}

/* 首屏数据带 */
.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(28px, 4vw, 46px) 0 0;
  padding: 0;
  background: rgba(201, 220, 234, .2);
  border: 1px solid rgba(201, 220, 234, .2);
}

@media (min-width: 760px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .about-facts__cell {
  background: rgba(7, 20, 39, .74);
  padding: 16px 16px 20px;
}

.page-about .about-facts dt {
  margin: 0 0 10px;
  font-family: var(--yb-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: rgba(201, 220, 234, .62);
}

.page-about .about-facts dd {
  margin: 0;
  display: flex;
  align-items: baseline;
  gap: 6px;
  font-family: var(--yb-mono);
  font-weight: 700;
  line-height: 1;
  color: var(--yb-ice);
}

.page-about .about-facts__num {
  font-size: clamp(26px, 3.6vw, 40px);
}

.page-about .about-facts__unit {
  font-family: var(--yb-body);
  font-size: 13px;
  font-weight: 400;
  letter-spacing: 0;
  color: rgba(201, 220, 234, .72);
}

/* ---------- 档案主体 ---------- */
.page-about .about-dossier {
  background: var(--yb-ice);
  padding: clamp(32px, 5.2vw, 64px) 0 clamp(42px, 6vw, 80px);
}

.page-about .about-dossier__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}

@media (min-width: 1000px) {
  .page-about .about-dossier__inner {
    grid-template-columns: var(--ab-rail) minmax(0, 1fr);
    gap: var(--ab-gap);
    align-items: start;
  }
}

/* 左侧档案目录 */
.page-about .about-rail {
  position: relative;
  border-bottom: 1px solid var(--yb-line);
  padding-bottom: 6px;
}

@media (min-width: 1000px) {
  .page-about .about-rail {
    position: sticky;
    top: calc(var(--yb-cmd-h) + var(--yb-strip-h) + 20px);
    border-bottom: 0;
    padding-bottom: 0;
  }
}

.page-about .about-rail__title {
  margin: 0 0 10px;
  font-family: var(--yb-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--yb-muted);
}

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

.page-about .about-rail__list::-webkit-scrollbar {
  display: none;
}

@media (min-width: 1000px) {
  .page-about .about-rail__list {
    display: block;
    overflow: visible;
    padding-bottom: 0;
  }
}

.page-about .about-rail__list a {
  display: block;
  white-space: nowrap;
  font-size: 13px;
  line-height: 1.4;
  padding: 7px 12px;
  color: var(--yb-muted);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: color .18s ease, border-color .18s ease;
}

@media (min-width: 1000px) {
  .page-about .about-rail__list a {
    white-space: normal;
    padding: 9px 0 9px 14px;
    border-bottom: 0;
    border-left: 2px solid rgba(201, 220, 234, .8);
  }
}

.page-about .about-rail__list a:hover {
  color: var(--yb-navy);
  border-color: var(--yb-cyan);
}

.page-about .about-rail__list a:focus-visible {
  outline: none;
  box-shadow: var(--yb-focus);
  color: var(--yb-navy);
  border-color: var(--yb-cyan);
}

.page-about .about-rail__list a[aria-current="true"] {
  color: var(--yb-navy);
  font-weight: 700;
  border-color: var(--yb-cyan);
}

/* ---------- 章节 ---------- */
.page-about .about-sec {
  scroll-margin-top: calc(var(--yb-cmd-h) + var(--yb-strip-h) + 18px);
  padding-bottom: clamp(30px, 4.4vw, 52px);
}

.page-about .about-sec + .about-sec {
  border-top: 1px solid var(--yb-line);
  padding-top: clamp(30px, 4.4vw, 52px);
}

.page-about .about-tag {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 14px;
  font-family: var(--yb-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .16em;
  color: var(--yb-navy);
}

.page-about .about-tag span {
  color: var(--yb-cyan);
}

.page-about .about-tag::after {
  content: "";
  flex: 0 0 auto;
  width: 46px;
  height: 1px;
  background: var(--yb-line);
}

.page-about .about-sec h2 {
  font-family: var(--yb-display);
  font-weight: 800;
  font-size: clamp(23px, 3.1vw, 36px);
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--yb-navy);
  margin: 0 0 16px;
  max-width: 24em;
}

.page-about .about-sec p {
  max-width: 42em;
  margin: 0 0 15px;
  color: var(--yb-navy);
}

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

.page-about .about-sec strong {
  color: var(--yb-navy);
  font-weight: 700;
}

/* 图文分栏 */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
}

@media (min-width: 840px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
    gap: 38px;
    align-items: start;
  }
}

.page-about .about-split--rev .about-split__text {
  order: 1;
}

.page-about .about-split--rev .about-media {
  order: 2;
}

@media (min-width: 840px) {
  .page-about .about-split--rev .about-split__text {
    order: 2;
  }
  .page-about .about-split--rev .about-media {
    order: 1;
  }
}

/* 媒体 */
.page-about .about-media {
  margin: 0;
}

.page-about .about-media .yb-media {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--yb-line);
  background: var(--yb-navy-2);
  box-shadow: var(--yb-shadow);
}

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

.page-about .yb-media--3x2 {
  aspect-ratio: 3 / 2;
}

.page-about .yb-media--4x3 {
  aspect-ratio: 4 / 3;
}

.page-about .about-media figcaption {
  margin-top: 10px;
  font-family: var(--yb-mono);
  font-size: 12px;
  line-height: 1.65;
  letter-spacing: .02em;
  color: var(--yb-muted);
}

.page-about .about-media--wide {
  margin-top: 24px;
}

/* 团队分工 */
.page-about .about-roles {
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 24px 0 0;
  padding: 0;
  background: var(--yb-line);
  border: 1px solid var(--yb-line);
}

@media (min-width: 760px) {
  .page-about .about-roles {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .about-roles > li {
  background: var(--yb-paper);
  padding: 20px 18px 22px;
}

.page-about .about-roles__num {
  display: block;
  font-family: var(--yb-mono);
  font-weight: 700;
  font-size: clamp(30px, 4vw, 42px);
  line-height: 1;
  color: var(--yb-navy);
  margin-bottom: 12px;
}

.page-about .about-roles h3 {
  font-family: var(--yb-display);
  font-size: 17px;
  font-weight: 700;
  letter-spacing: .01em;
  margin: 0 0 8px;
  color: var(--yb-navy-2);
}

.page-about .about-roles p {
  margin: 0;
  max-width: none;
  font-size: 14px;
  line-height: 1.72;
  color: var(--yb-muted);
}

/* 年龄段索引 */
.page-about .about-agegroup {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 22px 0 20px;
}

.page-about .about-agegroup a {
  font-family: var(--yb-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .06em;
  padding: 7px 15px;
  color: var(--yb-navy-2);
  background: var(--yb-paper);
  border: 1px solid var(--yb-line);
  text-decoration: none;
  transition: background .18s ease, color .18s ease, border-color .18s ease;
}

.page-about .about-agegroup a:hover {
  background: var(--yb-amber);
  border-color: var(--yb-amber);
  color: var(--yb-navy);
}

.page-about .about-agegroup a:focus-visible {
  outline: none;
  box-shadow: var(--yb-focus);
  background: var(--yb-amber);
  border-color: var(--yb-amber);
  color: var(--yb-navy);
}

/* 年龄段列表 */
.page-about .about-age-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--yb-line);
}

.page-about .about-age-item {
  display: grid;
  grid-template-columns: 76px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding: 15px 10px 15px 0;
  border-bottom: 1px solid var(--yb-line);
  scroll-margin-top: calc(var(--yb-cmd-h) + var(--yb-strip-h) + 24px);
  transition: background .2s ease;
}

.page-about .about-age-item:target {
  background: rgba(31, 224, 210, .09);
}

.page-about .about-age-item__code {
  position: relative;
  padding-left: 13px;
  font-family: var(--yb-mono);
  font-weight: 700;
  font-size: 18px;
  line-height: 1.5;
  color: var(--yb-navy);
  letter-spacing: .04em;
}

.page-about .about-age-item__code::before {
  content: "";
  position: absolute;
  left: 0;
  top: .58em;
  width: 6px;
  height: 6px;
  background: var(--yb-cyan);
}

.page-about .about-age-item p {
  margin: 0;
  max-width: 42em;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--yb-navy-2);
}

/* ---------- 核对表 ---------- */
.page-about .about-tablewrap {
  margin: 24px 0 0;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  border: 1px solid var(--yb-line);
  background: var(--yb-paper);
}

.page-about .about-table {
  width: 100%;
  min-width: 660px;
  border-collapse: collapse;
  font-size: 14.5px;
}

.page-about .about-table__cap {
  caption-side: top;
  text-align: left;
  padding: 13px 16px;
  font-family: var(--yb-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--yb-muted);
  background: var(--yb-ice-2);
  border-bottom: 1px solid var(--yb-line);
}

.page-about .about-table thead th {
  text-align: left;
  padding: 12px 16px;
  font-family: var(--yb-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .12em;
  color: var(--yb-navy-2);
  background: var(--yb-ice);
  border-bottom: 1px solid var(--yb-line);
  white-space: nowrap;
}

.page-about .about-table tbody th {
  text-align: left;
  padding: 16px;
  vertical-align: top;
  white-space: nowrap;
  font-size: 15px;
  font-weight: 700;
  color: var(--yb-navy);
  border-bottom: 1px solid var(--yb-line);
}

.page-about .about-table tbody td {
  padding: 16px;
  vertical-align: top;
  line-height: 1.72;
  color: var(--yb-navy-2);
  border-bottom: 1px solid var(--yb-line);
  border-left: 1px solid var(--yb-line);
}

.page-about .about-table tbody tr:nth-child(even) > * {
  background: var(--yb-ice);
}

.page-about .about-table tbody tr:last-child th,
.page-about .about-table tbody tr:last-child td {
  border-bottom: 0;
}

.page-about .about-chip {
  display: inline-block;
  margin: 0 4px 4px 0;
  padding: 2px 9px;
  font-family: var(--yb-mono);
  font-size: 12.5px;
  line-height: 1.65;
  white-space: nowrap;
  color: var(--yb-navy-2);
  background: var(--yb-ice-2);
  border: 1px solid var(--yb-line);
}

.page-about .about-chip--cyan {
  color: #0A5551;
  background: rgba(31, 224, 210, .17);
  border-color: rgba(31, 224, 210, .62);
}

.page-about .about-chip--amber {
  color: #7A4400;
  background: rgba(255, 159, 46, .17);
  border-color: rgba(255, 159, 46, .62);
}

.page-about .about-note {
  margin: 18px 0 0;
  padding: 14px 16px;
  max-width: 46em;
  font-size: 14px;
  line-height: 1.78;
  color: var(--yb-navy-2);
  background: rgba(255, 159, 46, .09);
  border-left: 3px solid var(--yb-amber);
}

/* ---------- 数据档案 ---------- */
.page-about .about-metrics {
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 8px;
  margin: 20px 0 0;
  padding: 0;
}

@media (min-width: 600px) {
  .page-about .about-metrics {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .about-metrics li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 10px 12px;
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--yb-navy-2);
  background: var(--yb-paper);
  border: 1px solid var(--yb-line);
}

.page-about .about-metrics__n {
  flex: 0 0 auto;
  font-family: var(--yb-mono);
  font-size: 20px;
  font-weight: 700;
  line-height: 1;
  color: var(--yb-navy);
}

.page-about .about-archive-note {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--yb-line);
  font-size: 14px;
  color: var(--yb-muted);
}

/* ---------- 合作 ---------- */
.page-about .about-partners {
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 22px 0 0;
  padding: 0;
  background: var(--yb-line);
  border: 1px solid var(--yb-line);
}

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

@media (min-width: 1080px) {
  .page-about .about-partners {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .about-partners > li {
  padding: 20px 18px 22px;
  background: var(--yb-paper);
}

.page-about .about-partners__n {
  display: block;
  margin-bottom: 10px;
  font-family: var(--yb-mono);
  font-weight: 700;
  font-size: 32px;
  line-height: 1;
  color: var(--yb-navy);
}

.page-about .about-partners h3 {
  margin: 0 0 6px;
  font-family: var(--yb-display);
  font-size: 16px;
  font-weight: 700;
  color: var(--yb-navy-2);
}

.page-about .about-partners p {
  margin: 0;
  max-width: none;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--yb-muted);
}

.page-about .about-honors {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 18px 0 0;
  padding: 0;
}

.page-about .about-honors li {
  padding: 8px 14px;
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--yb-navy-2);
  background: var(--yb-paper);
  border: 1px solid var(--yb-line);
  border-left: 3px solid var(--yb-amber);
}

/* ---------- 比赛日时间轴 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
}

.page-about .about-timeline > li {
  position: relative;
  padding: 0 0 24px 26px;
}

.page-about .about-timeline > li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .5em;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--yb-cyan);
}

.page-about .about-timeline > li::after {
  content: "";
  position: absolute;
  left: 4px;
  top: calc(.5em + 13px);
  bottom: 0;
  width: 1px;
  background: var(--yb-line);
}

.page-about .about-timeline > li:last-child {
  padding-bottom: 0;
}

.page-about .about-timeline > li:last-child::before {
  background: var(--yb-amber);
}

.page-about .about-timeline > li:last-child::after {
  display: none;
}

.page-about .about-timeline__time {
  display: block;
  margin-bottom: 5px;
  font-family: var(--yb-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--yb-muted);
}

.page-about .about-timeline p {
  margin: 0;
  max-width: 44em;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--yb-navy-2);
}

/* ---------- 结尾入口 ---------- */
.page-about .about-cta {
  background: var(--yb-navy-2);
  color: var(--yb-ice);
  padding: clamp(36px, 5.2vw, 66px) 0;
}

.page-about .about-cta__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
}

@media (min-width: 900px) {
  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 44px;
    align-items: center;
  }
}

.page-about .about-cta h2 {
  margin: 0 0 12px;
  font-family: var(--yb-display);
  font-weight: 800;
  font-size: clamp(22px, 3vw, 32px);
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--yb-ice);
}

.page-about .about-cta p {
  margin: 0;
  max-width: 44em;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(244, 249, 253, .78);
}

.page-about .about-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-cta .yb-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 9px 20px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  border-radius: var(--yb-r);
  transition: background .18s ease, color .18s ease, border-color .18s ease;
}

.page-about .about-cta .yb-btn--solid {
  background: var(--yb-cyan);
  border: 1px solid var(--yb-cyan);
  color: var(--yb-navy);
}

.page-about .about-cta .yb-btn--solid:hover,
.page-about .about-cta .yb-btn--solid:focus-visible {
  background: var(--yb-ice);
  border-color: var(--yb-ice);
  outline: none;
}

.page-about .about-cta .yb-btn--ghost {
  background: transparent;
  border: 1px solid rgba(201, 220, 234, .42);
  color: var(--yb-ice);
}

.page-about .about-cta .yb-btn--ghost:hover,
.page-about .about-cta .yb-btn--ghost:focus-visible {
  border-color: var(--yb-cyan);
  color: var(--yb-cyan);
  outline: none;
}

@media (min-width: 1000px) {
  .page-about .about-cta__links {
    flex-wrap: nowrap;
  }
}