.page-about {
  --about-pad: 56px;
  --about-line: rgba(138, 160, 191, .2);
  background: var(--night);
  color: #C9D5E6;
  font-family: var(--f-body);
  font-size: 15px;
  line-height: 1.75;
  overflow-x: hidden;
}

@media (min-width: 900px) {
  .page-about {
    --about-pad: 96px;
  }
}

.page-about .container {
  width: 100%;
  max-width: 1240px;
  margin-inline: auto;
  padding-inline: 18px;
  box-sizing: border-box;
}

@media (min-width: 760px) {
  .page-about .container {
    padding-inline: 32px;
  }
}

.page-about h1,
.page-about h2,
.page-about h3 {
  color: var(--cream);
  font-family: var(--f-display);
  font-weight: 900;
  font-stretch: 85%;
}

.page-about h2 {
  margin: 0 0 20px;
  letter-spacing: -.015em;
  line-height: 1.08;
}

.page-about h3 {
  margin: 0 0 10px;
  font-size: 16px;
  letter-spacing: .01em;
  line-height: 1.35;
}

.page-about p {
  margin: 0 0 16px;
}

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

.page-about .anno {
  display: block;
  margin: 0 0 14px;
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--slate);
  font-family: var(--f-body);
  font-weight: 500;
}

.page-about .display--xl {
  font-size: clamp(34px, 9vw, 72px);
  line-height: 1.02;
  letter-spacing: -.025em;
}

.page-about .display--lg {
  font-size: clamp(27px, 5.6vw, 46px);
}

.page-about .display--md {
  font-size: clamp(22px, 4.6vw, 32px);
}

.page-about .lede {
  color: #E2E9F5;
  font-size: 15.5px;
  line-height: 1.8;
  max-width: 68ch;
}

.page-about .sec-head {
  max-width: 720px;
}

.page-about .inline-link {
  color: var(--teal);
  text-decoration: none;
  border-bottom: 1px solid rgba(0, 224, 200, .42);
  transition: border-color .2s var(--ease), color .2s var(--ease);
}

.page-about .inline-link:hover,
.page-about .inline-link:focus-visible {
  border-bottom-color: var(--teal);
  color: var(--mist);
}

/* ---------- 面包屑 ---------- */

.page-about .breadcrumb {
  padding-top: 24px;
}

.page-about .breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--slate);
}

.page-about .breadcrumb li:not(:first-child)::before {
  content: "·";
  margin-right: 8px;
  color: rgba(138, 160, 191, .55);
}

.page-about .breadcrumb a {
  color: var(--slate);
  text-decoration: none;
  transition: color .2s var(--ease);
}

.page-about .breadcrumb a:hover,
.page-about .breadcrumb a:focus-visible {
  color: var(--teal);
}

.page-about .breadcrumb-current {
  color: var(--cream);
}

/* ---------- 首屏 ---------- */

.about-hero {
  position: relative;
  padding: 30px 0 var(--about-pad);
  overflow: hidden;
}

.about-hero::before {
  content: "";
  position: absolute;
  top: -140px;
  left: -25%;
  width: 130%;
  height: 560px;
  background: radial-gradient(58% 58% at 32% 30%, rgba(0, 224, 200, .17), transparent 70%);
  pointer-events: none;
}

.about-hero-inner {
  position: relative;
}

.about-hero h1 {
  margin: 0 0 24px;
}

.hero-em {
  color: var(--teal);
  display: inline-block;
}

.hero-stats {
  list-style: none;
  margin: 34px 0 0;
  padding: 20px 0 0;
  border-top: 1px solid var(--about-line);
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.stat-num {
  display: block;
  font-family: var(--f-data);
  font-variant-numeric: tabular-nums;
  font-size: clamp(20px, 5.4vw, 32px);
  line-height: 1.15;
  letter-spacing: .01em;
  color: var(--gold);
}

.stat-label {
  display: block;
  margin-top: 4px;
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--slate);
}

.about-figure {
  margin: 42px 0 0;
  position: relative;
}

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

.about-figure::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 32px;
  height: 2px;
  background: linear-gradient(90deg, var(--teal), var(--orange) 62%, var(--gold));
  opacity: .8;
}

.fig-cap {
  margin-top: 12px;
  font-size: 12px;
  color: var(--slate);
}

/* ---------- 对位入口 ---------- */

.about-unit {
  padding: 0 0 var(--about-pad);
}

.about-unit .grid--7-3 {
  display: grid;
  grid-template-columns: 1fr;
  gap: 34px;
}

@media (min-width: 900px) {
  .about-unit .grid--7-3 {
    grid-template-columns: minmax(0, 7fr) minmax(0, 3fr);
    gap: 64px;
    align-items: start;
  }
}

.unit-main p {
  max-width: 62ch;
}

.unit-side {
  background: var(--field);
  padding: 22px 20px 24px;
  border-top: 2px solid var(--teal);
}

.unit-side .anno {
  margin-bottom: 16px;
}

.unit-svg {
  display: block;
  width: 100%;
  height: auto;
}

.unit-svg .n-box {
  fill: none;
  stroke: var(--teal);
  stroke-width: 1.4;
}

.unit-svg .n-box--alt {
  stroke: var(--orange);
}

.unit-svg .n-link {
  fill: none;
  stroke: rgba(0, 224, 200, .5);
  stroke-width: 1.2;
}

.unit-svg .n-node {
  fill: rgba(0, 224, 200, .12);
  stroke: var(--teal);
  stroke-width: 1.6;
}

.unit-svg .n-label {
  fill: #C9D5E6;
  font-family: var(--f-body);
  font-size: 11px;
  letter-spacing: .04em;
}

.unit-svg .n-label--core {
  fill: var(--cream);
  font-size: 12px;
}

/* ---------- 赛事版图 ---------- */

.about-map {
  padding: var(--about-pad) 0;
  background: linear-gradient(180deg, #0B1B36 0%, var(--field) 100%);
}

.map-stack {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 36px;
}

.tier {
  border-left: 3px solid var(--teal);
}

.tier--l1 {
  background: #17335C;
}

.tier--l2 {
  background: #112646;
}

.tier--l3 {
  background: #0A1730;
}

.tier > summary {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: baseline;
  gap: 10px 14px;
  padding: 18px 18px;
  cursor: pointer;
  list-style: none;
}

.tier > summary::-webkit-details-marker {
  display: none;
}

.tier > summary:focus-visible {
  outline: 2px solid var(--teal);
  outline-offset: -2px;
}

.tier-id {
  font-family: var(--f-data);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--slate);
}

.tier-title {
  color: var(--cream);
  font-family: var(--f-display);
  font-weight: 900;
  font-stretch: 85%;
  font-size: clamp(18px, 3.6vw, 24px);
  letter-spacing: -.01em;
  line-height: 1.2;
}

.tier-title::after {
  content: "";
  display: inline-block;
  margin-left: 12px;
  width: 7px;
  height: 7px;
  border-right: 2px solid var(--teal);
  border-bottom: 2px solid var(--teal);
  transform: rotate(45deg) translateY(-3px);
  transition: transform .24s var(--ease);
}

.tier[open] .tier-title::after {
  transform: rotate(-135deg) translateY(-1px);
}

.tier-count {
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--slate);
  white-space: nowrap;
}

.tier-count .data {
  font-family: var(--f-data);
  font-variant-numeric: tabular-nums;
  font-size: 16px;
  color: var(--gold);
  margin-right: 4px;
}

.tier-list {
  list-style: none;
  margin: 0;
  padding: 0 18px 20px;
  display: grid;
  gap: 12px;
}

.tier-list li {
  border-top: 1px solid rgba(138, 160, 191, .16);
  padding-top: 12px;
}

.li-head {
  display: block;
  font-size: 13.5px;
  color: var(--cream);
  letter-spacing: .01em;
}

.li-head .data {
  font-family: var(--f-data);
  font-variant-numeric: tabular-nums;
  color: var(--teal);
  margin-left: 6px;
}

.tier--l2 .li-head .data {
  color: var(--orange);
}

.li-desc {
  display: block;
  margin-top: 2px;
  font-size: 13px;
  line-height: 1.7;
  color: #AFC0D8;
}

.map-figure {
  margin: 40px 0 0;
}

.map-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 更新节奏 ---------- */

.about-cadence {
  position: relative;
  padding: var(--about-pad) 0;
  overflow: hidden;
}

.about-cadence::before {
  content: "";
  position: absolute;
  top: -80px;
  right: -20%;
  width: 90%;
  height: 420px;
  background: radial-gradient(50% 50% at 70% 40%, rgba(255, 106, 44, .14), transparent 70%);
  pointer-events: none;
}

.about-cadence .grid--7-3 {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
}

@media (min-width: 900px) {
  .about-cadence .grid--7-3 {
    grid-template-columns: minmax(0, 7fr) minmax(0, 3fr);
    gap: 64px;
    align-items: start;
  }
}

.about-cadence p {
  max-width: 62ch;
}

.cadence-side {
  padding-top: 18px;
  border-top: 1px solid var(--about-line);
}

.cadence-ver {
  font-family: var(--f-data);
  font-variant-numeric: tabular-nums;
  font-size: clamp(44px, 11vw, 68px);
  line-height: 1;
  color: var(--gold);
  margin: 4px 0 12px;
}

.cadence-side .footnote {
  font-size: 12px;
  line-height: 1.75;
  color: var(--slate);
  margin: 0;
}

/* ---------- 团队 ---------- */

.about-team {
  padding: 0 0 var(--about-pad);
}

.team-cols {
  display: grid;
  grid-template-columns: 1fr;
  gap: 34px;
  margin-top: 42px;
}

@media (min-width: 780px) {
  .team-cols {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 48px;
  }
}

.team-col p:not(.team-num) {
  font-size: 13.5px;
  line-height: 1.75;
  color: #AFC0D8;
}

.team-num {
  font-family: var(--f-data);
  font-variant-numeric: tabular-nums;
  font-size: clamp(34px, 8vw, 48px);
  line-height: 1;
  margin: 0 0 12px;
  color: var(--teal);
}

.team-col:nth-child(2) .team-num {
  color: var(--orange);
}

.team-col:nth-child(3) .team-num {
  color: var(--gold);
}

/* ---------- 发展历程 ---------- */

.about-timeline {
  padding: var(--about-pad) 0;
  background: var(--field);
}

.tl-hint {
  max-width: 1240px;
  margin: 28px auto 0;
  padding-inline: 18px;
  box-sizing: border-box;
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--slate);
}

@media (min-width: 760px) {
  .tl-hint {
    padding-inline: 32px;
  }
}

.tl-track {
  display: flex;
  gap: 16px;
  max-width: 1240px;
  margin: 14px auto 0;
  padding: 6px 18px 26px;
  box-sizing: border-box;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
  scrollbar-color: rgba(0, 224, 200, .55) transparent;
}

@media (min-width: 760px) {
  .tl-track {
    padding-inline: 32px;
    gap: 22px;
  }
}

.tl-track::-webkit-scrollbar {
  height: 4px;
}

.tl-track::-webkit-scrollbar-thumb {
  background: rgba(0, 224, 200, .55);
}

.tl-track::-webkit-scrollbar-track {
  background: rgba(138, 160, 191, .15);
}

.tl-item {
  flex: 0 0 76vw;
  max-width: 320px;
  scroll-snap-align: start;
  background: rgba(10, 23, 48, .75);
  border-top: 3px solid var(--gold);
  padding: 20px 18px 22px;
}

@media (min-width: 760px) {
  .tl-item {
    flex: 0 0 290px;
  }
}

.tl-year {
  font-family: var(--f-data);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--gold);
  margin: 0 0 10px;
}

.tl-item p:not(.tl-year) {
  font-size: 13.5px;
  line-height: 1.75;
  color: #AFC0D8;
}

.tl-figure {
  margin: 20px 0 0;
}

.tl-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 合作生态 ---------- */

.about-eco {
  padding: var(--about-pad) 0;
  background: var(--night);
}

.eco-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin-top: 36px;
}

@media (min-width: 780px) {
  .eco-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px;
  }
}

.eco-card {
  background: #0E2140;
  border-left: 3px solid var(--orange);
  padding: 22px 20px 24px;
}

.eco-card p:not(.eco-num) {
  font-size: 13.5px;
  line-height: 1.75;
  color: #AFC0D8;
}

.eco-num {
  font-family: var(--f-data);
  font-variant-numeric: tabular-nums;
  font-size: 32px;
  line-height: 1;
  color: var(--orange);
  margin: 0 0 12px;
}

.eco-cta {
  margin: 26px 0 0;
  font-size: 13.5px;
  color: #AFC0D8;
}

/* ---------- 收尾 ---------- */

.about-cta {
  padding: var(--about-pad) 0;
  background: linear-gradient(135deg, #0B1B36 0%, #14305A 58%, #0A1730 100%);
}

.about-cta p {
  max-width: 60ch;
  color: #C9D5E6;
}

.cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 26px;
}

@media (max-width: 520px) {
  .about-cta .btn {
    width: 100%;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .inline-link,
  .page-about .breadcrumb a,
  .tier-title::after {
    transition: none;
  }
}