.page-about {
  --about-idx: 210px;
  --about-shell-gap: clamp(32px, 4vw, 72px);
  --about-block-pad: clamp(24px, 3.4vw, 52px);
}

/* ---------- 首屏 ---------- */
.page-about__hero {
  position: relative;
  overflow: hidden;
  padding-top: calc(var(--header-h) + clamp(28px, 5vw, 64px));
  padding-bottom: clamp(40px, 6vw, 88px);
}
.page-about__hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.page-about__hero-bg img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.36;
  filter: saturate(0.62) contrast(1.06);
}
.page-about__hero-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(110% 90% at 78% 8%, rgba(79, 240, 224, 0.13), transparent 62%),
    linear-gradient(180deg, rgba(10, 14, 18, 0.5) 0%, rgba(10, 14, 18, 0.86) 58%, var(--ink) 100%);
}
.page-about__hero-inner {
  position: relative;
  z-index: 1;
}
.page-about__crumb {
  margin-bottom: clamp(28px, 5vw, 56px);
}
.page-about__h1 {
  margin: 14px 0 0;
  font-size: clamp(36px, 7.2vw, 96px);
  line-height: 1.06;
  letter-spacing: -0.02em;
  font-weight: 300;
}
.page-about__lede {
  margin: clamp(20px, 3vw, 32px) 0 0;
  max-width: 46ch;
}

/* 首屏数据条 */
.page-about__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(32px, 4.5vw, 56px) 0 0;
  padding: 0;
  list-style: none;
  background: var(--line-soft);
  border: 1px solid var(--line);
}
@media (min-width: 720px) {
  .page-about__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}
.page-about__stat {
  background: rgba(10, 14, 18, 0.86);
  padding: 16px clamp(14px, 2vw, 22px);
  min-width: 0;
}
.page-about__stat dt {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--mist);
}
.page-about__stat dd {
  margin: 10px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(22px, 3.2vw, 34px);
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--paper);
}

/* ---------- 双栏骨架 ---------- */
.page-about__shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-shell-gap);
  padding-top: clamp(48px, 7vw, 104px);
  padding-bottom: clamp(60px, 9vw, 130px);
}
@media (min-width: 1000px) {
  .page-about__shell {
    grid-template-columns: var(--about-idx) minmax(0, 1fr);
    align-items: start;
  }
}

/* ---------- 左侧索引 ---------- */
.page-about__index {
  min-width: 0;
}
@media (min-width: 1000px) {
  .page-about__index {
    position: sticky;
    top: calc(var(--header-h) + 28px);
  }
}
.page-about__index-label {
  margin: 0;
  color: var(--cyan);
}
.page-about__index-list {
  list-style: none;
  margin: 14px 0 0;
  padding: 14px 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  border-top: 1px solid var(--line);
}
.page-about__index-list a {
  display: block;
  padding: 8px 14px;
  min-height: 44px;
  line-height: 26px;
  border: 1px solid var(--line);
  color: var(--mist);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);
}
.page-about__index-list a:hover,
.page-about__index-list a:focus-visible {
  color: var(--cyan);
  border-color: var(--line-cyan);
}
@media (min-width: 1000px) {
  .page-about__index-list {
    display: grid;
    gap: 0;
    padding: 0;
    border-top: 0;
    border-left: 1px solid var(--line);
  }
  .page-about__index-list a {
    margin-left: -1px;
    padding: 12px 0 12px 16px;
    min-height: 0;
    line-height: 1.5;
    border: 0;
    border-left: 2px solid transparent;
  }
  .page-about__index-list a:hover,
  .page-about__index-list a:focus-visible {
    border-left-color: var(--cyan);
    color: var(--cyan);
  }
}

/* ---------- 纵向长卷 ---------- */
.page-about__roll {
  display: grid;
  gap: clamp(56px, 8vw, 118px);
  min-width: 0;
}
.page-about__block {
  position: relative;
  min-width: 0;
  scroll-margin-top: calc(var(--header-h) + 28px);
}
.page-about__block--indigo,
.page-about__block--wine,
.page-about__block--teal {
  padding: var(--about-block-pad);
  border: 1px solid var(--line);
}
.page-about__block--indigo {
  background: linear-gradient(158deg, var(--indigo) 0%, rgba(19, 26, 43, 0.4) 100%);
}
.page-about__block--wine {
  background: linear-gradient(158deg, var(--wine) 0%, rgba(42, 18, 32, 0.45) 100%);
}
.page-about__block--teal {
  background: linear-gradient(158deg, var(--teal) 0%, rgba(12, 38, 36, 0.45) 100%);
}
.page-about__block-lede {
  margin: clamp(16px, 2.2vw, 24px) 0 0;
  max-width: 46ch;
}

/* ---------- 赛季里程碑带 ---------- */
.page-about__rail {
  list-style: none;
  margin: clamp(28px, 4vw, 48px) 0 0;
  padding: 0 0 24px;
  display: flex;
  gap: 0;
  overflow-x: auto;
  overscroll-behavior-x: contain;
  scroll-snap-type: x proximity;
  border-bottom: 1px solid var(--line-cyan);
}
.page-about__rail::-webkit-scrollbar {
  height: 3px;
}
.page-about__rail::-webkit-scrollbar-track {
  background: var(--line-soft);
}
.page-about__rail::-webkit-scrollbar-thumb {
  background: var(--line-cyan);
}
.page-about__node {
  position: relative;
  flex: 0 0 min(272px, 76vw);
  padding: 0 clamp(20px, 3vw, 34px) 0 0;
  scroll-snap-align: start;
  min-width: 0;
}
.page-about__node::before {
  content: "";
  display: block;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--ink);
  border: 3px solid var(--cyan);
  margin-bottom: 18px;
  transition: background var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease);
}
.page-about__node:hover::before,
.page-about__node:focus-within::before {
  background: var(--cyan);
  transform: scale(1.3);
  box-shadow: 0 0 0 6px rgba(79, 240, 224, 0.14);
}
.page-about__node-season {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--amber);
}
.page-about__node-title {
  margin: 10px 0 0;
  font-size: clamp(17px, 1.6vw, 20px);
  font-weight: 700;
  line-height: 1.4;
  color: var(--paper);
}
.page-about__node-text {
  margin: 10px 0 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--mist);
}
.page-about__rail-hint {
  margin: 14px 0 0;
}

/* ---------- 团队分工 ---------- */
.page-about__crew {
  display: grid;
  gap: clamp(22px, 2.8vw, 36px);
  margin-top: clamp(32px, 4vw, 52px);
}
@media (min-width: 760px) {
  .page-about__crew {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: clamp(24px, 3vw, 44px);
  }
}
.page-about__crew-item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  column-gap: clamp(14px, 2vw, 24px);
  align-items: start;
  padding-top: 18px;
  border-top: 1px solid var(--line-cyan);
  min-width: 0;
}
.page-about__crew-num {
  grid-column: 1;
  grid-row: 1;
  font-size: clamp(34px, 4.6vw, 54px);
  line-height: 0.88;
  letter-spacing: -0.03em;
  color: var(--cyan);
}
.page-about__crew-item h3 {
  grid-column: 2;
  grid-row: 1;
  margin: 8px 0 0;
  font-size: 17px;
  font-weight: 700;
  color: var(--paper);
}
.page-about__crew-item p {
  grid-column: 2;
  grid-row: 2;
  margin: 10px 0 0;
  max-width: 40ch;
  font-size: 15px;
  line-height: 1.72;
  color: var(--mist);
}

/* ---------- 五步入库流程 ---------- */
.page-about__process {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
  margin-top: clamp(32px, 4vw, 52px);
}
@media (min-width: 880px) {
  .page-about__process {
    grid-template-columns: minmax(0, 0.82fr) minmax(0, 1.18fr);
    align-items: start;
    gap: clamp(32px, 4.5vw, 64px);
  }
}
.page-about__process-fig {
  margin: 0;
  min-width: 0;
}
.page-about__process-fig figcaption {
  margin-top: 14px;
}
@media (min-width: 880px) {
  .page-about__process-fig {
    position: sticky;
    top: calc(var(--header-h) + 32px);
  }
}
.page-about__steps {
  border-top: 1px solid var(--line);
  min-width: 0;
}
.page-about__step {
  border-bottom: 1px solid var(--line);
}
.page-about__step summary {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 18px 0;
  min-height: 44px;
  cursor: pointer;
  list-style: none;
  color: var(--paper);
  font-size: clamp(16px, 1.6vw, 19px);
  font-weight: 700;
  transition: color var(--dur-fast) var(--ease);
}
.page-about__step summary::-webkit-details-marker {
  display: none;
}
.page-about__step summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--cyan);
}
.page-about__step[open] summary::after {
  content: "−";
}
.page-about__step summary:hover,
.page-about__step summary:focus-visible {
  color: var(--cyan);
}
.page-about__step summary .mono {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--mist);
}
.page-about__step[open] summary .mono {
  color: var(--cyan);
}
.page-about__step p {
  margin: 0 0 20px;
  max-width: 48ch;
  font-size: 15.5px;
  line-height: 1.76;
  color: var(--mist);
}

/* ---------- 评分维度 ---------- */
.page-about__score {
  display: grid;
  gap: clamp(14px, 2vw, 22px);
  margin-top: clamp(28px, 3.6vw, 44px);
}
@media (min-width: 720px) {
  .page-about__score {
    grid-template-columns: auto minmax(0, 1fr);
    align-items: end;
    gap: clamp(20px, 3vw, 36px);
  }
}
.page-about__score-anchor {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(58px, 10vw, 116px);
  line-height: 0.86;
  letter-spacing: -0.04em;
  color: var(--label);
}
.page-about__score-note {
  margin: 0;
  max-width: 52ch;
}
.page-about__dims {
  list-style: none;
  margin: clamp(32px, 4vw, 52px) 0 0;
  padding: 0;
}
.page-about__dim {
  display: grid;
  grid-template-columns: clamp(38px, 5vw, 62px) minmax(0, 1fr);
  gap: clamp(14px, 2vw, 26px);
  padding: clamp(18px, 2.4vw, 26px) 0;
  border-top: 1px solid var(--line);
  min-width: 0;
}
.page-about__dim:last-child {
  border-bottom: 1px solid var(--line);
}
.page-about__dim-num {
  font-size: clamp(18px, 2.2vw, 26px);
  line-height: 1.2;
  letter-spacing: 0.02em;
  color: var(--amber);
}
.page-about__dim h3 {
  margin: 0;
  font-size: 17px;
  font-weight: 700;
  color: var(--paper);
}
.page-about__dim p {
  margin: 8px 0 0;
  max-width: 46ch;
  font-size: 15px;
  line-height: 1.74;
  color: var(--mist);
}

/* ---------- 合作与节点 ---------- */
.page-about__eco {
  display: grid;
  gap: clamp(28px, 4vw, 52px);
  margin-top: clamp(28px, 4vw, 48px);
}
@media (min-width: 880px) {
  .page-about__eco {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: start;
  }
}
.page-about__eco-text {
  min-width: 0;
}
.page-about__eco-fig {
  margin: 0;
  min-width: 0;
}
.page-about__eco-fig figcaption {
  margin-top: 14px;
}
.page-about__eco-list {
  list-style: none;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 0;
}
.page-about__eco-list li {
  display: grid;
  grid-template-columns: 8px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding: 14px 0;
  border-top: 1px solid var(--line);
  font-size: 15.5px;
  line-height: 1.74;
  color: var(--mist);
}
.page-about__eco-list li::before {
  content: "";
  width: 8px;
  height: 8px;
  margin-top: 9px;
  background: var(--cyan);
}

/* ---------- 收尾 ---------- */
.page-about__cta {
  padding-top: clamp(32px, 4vw, 52px);
  border-top: 1px solid var(--line-cyan);
}
.page-about__cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(22px, 3vw, 34px);
}
.page-about__cta-actions .btn {
  min-height: 44px;
}

/* ---------- 通用可达性 ---------- */
.page-about a:focus-visible,
.page-about summary:focus-visible,
.page-about [tabindex]:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}
.page-about .media-frame img {
  max-width: 100%;
  height: auto;
  display: block;
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: 0.01ms;
    animation-duration: 0.01ms;
  }
}