.page-about {
  --about-axis-w: 196px;
  --about-col-gap: clamp(26px, 4vw, 56px);
  --about-hair: rgba(53, 230, 224, .18);
  --about-hair-soft: rgba(53, 230, 224, .1);
  --about-dim: rgba(246, 241, 231, .68);
  --about-dim-2: rgba(246, 241, 231, .52);
  display: block;
}

/* ============ 首屏 ============ */
.page-about .about-hero {
  padding-block: clamp(18px, 3vw, 34px) clamp(30px, 5vw, 64px);
}

.page-about .about-hero__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 46px);
  margin-top: clamp(20px, 3.2vw, 38px);
}

.page-about .about-hero__eyebrow {
  color: var(--fy-cyan);
}

.page-about .about-hero__title {
  margin: 12px 0 0;
  color: var(--fy-paper);
}

.page-about .about-hero__lede {
  margin: 20px 0 0;
  max-width: 34em;
  font-family: var(--fy-font-body);
  font-size: 16px;
  line-height: 1.82;
  color: rgba(246, 241, 231, .78);
}

.page-about .about-hero__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
}

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

.page-about .about-hero__figure .fy-media__img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
}

@media (min-width: 940px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, .92fr);
    align-items: end;
  }
}

/* ============ 主体骨架 ============ */
.page-about .about-body {
  padding-bottom: clamp(46px, 7vw, 96px);
}

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

@media (min-width: 1024px) {
  .page-about .about-grid {
    grid-template-columns: var(--about-axis-w) minmax(0, 1fr);
  }
}

/* ============ 左侧编年轴 ============ */
.page-about .about-axis {
  align-self: start;
}

.page-about .about-axis__eyebrow {
  margin: 0;
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--about-dim-2);
}

.page-about .about-axis__list {
  display: flex;
  gap: 8px;
  margin: 12px 0 0;
  padding: 0 0 10px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

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

.page-about .about-axis__link {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--about-hair-soft);
  border-radius: var(--fy-pill);
  font-size: 13px;
  white-space: nowrap;
  color: var(--about-dim);
  text-decoration: none;
  transition: border-color .22s var(--fy-ease), color .22s var(--fy-ease), background-color .22s var(--fy-ease);
}

.page-about .about-axis__link:hover,
.page-about .about-axis__link:focus-visible {
  border-color: var(--fy-cyan);
  color: var(--fy-paper);
  background-color: rgba(53, 230, 224, .07);
}

.page-about .about-axis__num {
  font-size: 12px;
  color: var(--fy-cyan);
  letter-spacing: .04em;
}

@media (min-width: 1024px) {
  .page-about .about-axis {
    position: sticky;
    top: calc(var(--fy-shell-space) + 18px);
  }

  .page-about .about-axis__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding: 0;
    margin-left: 5px;
    border-left: 1px solid var(--about-hair);
  }

  .page-about .about-axis__link {
    position: relative;
    border: 0;
    border-radius: 0;
    padding: 10px 0 10px 18px;
    white-space: normal;
    background: none;
  }

  .page-about .about-axis__link::before {
    content: "";
    position: absolute;
    left: -5px;
    top: 50%;
    width: 7px;
    height: 7px;
    margin-top: -4px;
    border-radius: 50%;
    background: var(--fy-night);
    border: 1px solid var(--fy-edge);
    transition: background-color .22s var(--fy-ease), border-color .22s var(--fy-ease), box-shadow .22s var(--fy-ease);
  }

  .page-about .about-axis__link:hover::before,
  .page-about .about-axis__link:focus-visible::before {
    background: var(--fy-cyan);
    border-color: var(--fy-cyan);
    box-shadow: 0 0 0 4px rgba(53, 230, 224, .14);
  }
}

/* ============ 章节通用 ============ */
.page-about .about-chapter {
  padding-bottom: clamp(38px, 5.4vw, 68px);
  scroll-margin-top: calc(var(--fy-shell-space) + 28px);
}

.page-about .about-chapter:last-child {
  padding-bottom: 0;
}

.page-about .about-chapter__head {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  grid-template-areas:
    "idx title"
    "idx lede";
  column-gap: 16px;
  align-items: baseline;
  padding-top: 16px;
  margin-bottom: clamp(20px, 3vw, 30px);
  border-top: 1px solid var(--about-hair);
}

.page-about .about-chapter__index {
  grid-area: idx;
  font-size: 20px;
  line-height: 1.2;
  color: var(--fy-cyan);
  letter-spacing: .06em;
}

.page-about .about-chapter__title {
  grid-area: title;
  margin: 0;
  color: var(--fy-paper);
}

.page-about .about-chapter__lede {
  grid-area: lede;
  margin: 12px 0 0;
  max-width: 38em;
  font-size: 15px;
  line-height: 1.8;
  color: var(--about-dim);
}

/* ============ A 编年 ============ */
.page-about .about-steps {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

@media (min-width: 720px) {
  .page-about .about-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .about-steps__item {
  position: relative;
  padding: 18px 18px 20px;
  border: 1px solid var(--about-hair-soft);
  border-radius: 14px;
  background: linear-gradient(158deg, rgba(22, 80, 140, .2), rgba(42, 19, 87, .18));
}

.page-about .about-steps__item::before {
  content: "";
  position: absolute;
  left: 18px;
  top: 0;
  width: 30px;
  height: 2px;
  background: var(--fy-cyan);
  opacity: .55;
}

.page-about .about-steps__tag {
  margin: 0;
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--fy-cyan);
}

.page-about .about-steps__title {
  margin: 10px 0 8px;
  font-family: var(--fy-font-body);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--fy-paper);
}

.page-about .about-steps__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--about-dim);
}

/* ============ 过渡图 ============ */
.page-about .about-bleed {
  margin: 0 0 clamp(38px, 5.4vw, 68px);
}

.page-about .about-bleed .fy-media__img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
}

/* ============ B 档案卡 ============ */
.page-about .about-dossiers {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

@media (min-width: 780px) {
  .page-about .about-dossiers {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    align-items: start;
  }
}

.page-about .about-dossier {
  border: 1px solid var(--about-hair-soft);
  border-radius: 14px;
  background: rgba(10, 24, 48, .48);
  overflow: hidden;
}

.page-about .about-dossier[open] {
  border-color: var(--about-hair);
}

.page-about .about-dossier__summary {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr) auto;
  align-items: center;
  gap: 12px;
  padding: 15px 16px;
  cursor: pointer;
  list-style: none;
  font-size: 15px;
  font-weight: 700;
  color: var(--fy-paper);
}

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

.page-about .about-dossier__summary::after {
  content: "+";
  font-family: var(--fy-font-mono);
  font-size: 16px;
  line-height: 1;
  color: var(--fy-cyan);
  transition: transform .2s var(--fy-ease);
}

.page-about .about-dossier[open] .about-dossier__summary::after {
  content: "−";
}

.page-about .about-dossier__num {
  font-size: 12px;
  color: var(--fy-orange);
  letter-spacing: .08em;
}

.page-about .about-dossier__title {
  font-family: var(--fy-font-body);
}

.page-about .about-dossier__body {
  padding: 12px 16px 16px 62px;
  border-top: 1px solid rgba(53, 230, 224, .09);
  font-size: 14px;
  line-height: 1.8;
  color: var(--about-dim);
}

.page-about .about-dossier__body p {
  margin: 0;
}

/* ============ 数据带 ============ */
.page-about .about-metrics {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(132px, 1fr));
  gap: 1px;
  margin: clamp(26px, 3.8vw, 44px) 0 0;
  border: 1px solid var(--about-hair);
  border-radius: 16px;
  background: var(--about-hair-soft);
  overflow: hidden;
}

.page-about .about-metrics__item {
  padding: 18px 16px 20px;
  background: linear-gradient(165deg, rgba(10, 24, 48, .94), rgba(42, 19, 87, .88));
}

.page-about .about-metrics__value {
  margin: 0;
  font-family: var(--fy-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(23px, 3vw, 32px);
  line-height: 1.1;
  color: var(--fy-cyan);
  letter-spacing: -.01em;
}

.page-about .about-metrics__label {
  margin: 9px 0 0;
  font-size: 13px;
  line-height: 1.5;
  color: var(--about-dim);
}

/* ============ C 三条主线 ============ */
.page-about .about-lanes {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
}

@media (min-width: 800px) {
  .page-about .about-lanes {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    align-items: start;
  }

  .page-about .about-lanes__item:nth-child(2) {
    margin-top: 30px;
  }

  .page-about .about-lanes__item:nth-child(3) {
    margin-top: 60px;
  }
}

.page-about .about-lanes__item {
  padding: 22px 20px 24px;
  background: linear-gradient(152deg, rgba(22, 80, 140, .32), rgba(42, 19, 87, .3));
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 0 100%);
}

.page-about .about-lanes__num {
  margin: 0;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--fy-orange);
}

.page-about .about-lanes__title {
  margin: 12px 0 10px;
  font-family: var(--fy-font-display);
  font-size: 19px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--fy-paper);
}

.page-about .about-lanes__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--about-dim);
}

.page-about .about-lanes__link {
  display: inline-block;
  margin-top: 16px;
  padding-bottom: 2px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .04em;
  color: var(--fy-cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--fy-edge);
  transition: border-color .22s var(--fy-ease), color .22s var(--fy-ease);
}

.page-about .about-lanes__link:hover,
.page-about .about-lanes__link:focus-visible {
  color: var(--fy-paper);
  border-bottom-color: var(--fy-cyan);
}

.page-about .about-chapters__note {
  margin: clamp(24px, 3.4vw, 38px) 0 0;
  padding-left: 16px;
  border-left: 2px solid var(--fy-orange);
  font-size: 14px;
  line-height: 1.8;
  color: var(--about-dim);
  max-width: 44em;
}

/* ============ D 团队与流程（纸面册页） ============ */
.page-about .about-sheet {
  padding: clamp(22px, 3.4vw, 40px);
  border-radius: var(--fy-radius-lg);
  background: var(--fy-paper);
  color: var(--fy-ink);
  box-shadow: var(--fy-glow);
}

.page-about .about-sheet .about-chapter__head {
  border-top-color: rgba(20, 22, 26, .16);
}

.page-about .about-chapter__head--sheet .about-chapter__index {
  color: var(--fy-deep-orange);
}

.page-about .about-chapter__title--sheet {
  color: var(--fy-ink);
}

.page-about .about-chapter__lede--sheet {
  color: var(--fy-slate);
}

.page-about .about-team__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3vw, 36px);
}

@media (min-width: 880px) {
  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr);
    align-items: start;
  }
}

.page-about .about-team__subtitle {
  margin: 0;
  font-family: var(--fy-font-body);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .1em;
  color: var(--fy-deep-orange);
}

.page-about .about-team__subtitle--flow {
  margin-top: 34px;
}

.page-about .about-roles {
  margin: 14px 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid rgba(20, 22, 26, .12);
}

.page-about .about-roles__item {
  display: grid;
  grid-template-columns: 1fr auto;
  grid-template-areas:
    "name num"
    "desc desc";
  gap: 4px 14px;
  align-items: baseline;
  padding: 13px 0;
  border-bottom: 1px solid rgba(20, 22, 26, .12);
}

.page-about .about-roles__name {
  grid-area: name;
  font-size: 15px;
  font-weight: 700;
  color: var(--fy-ink);
}

.page-about .about-roles__desc {
  grid-area: desc;
  font-size: 13px;
  line-height: 1.7;
  color: var(--fy-slate);
}

.page-about .about-roles__num {
  grid-area: num;
  font-size: 20px;
  color: var(--fy-deep-orange);
  font-variant-numeric: tabular-nums;
}

.page-about .about-roles__total {
  margin: 14px 0 0;
  font-size: 13px;
  color: var(--fy-slate);
}

.page-about .about-roles__total .fy-mono {
  color: var(--fy-ink);
  font-weight: 700;
}

.page-about .about-flow {
  margin: 14px 0 0;
  padding: 0;
  list-style: none;
  counter-reset: about-flow;
}

.page-about .about-flow__item {
  position: relative;
  counter-increment: about-flow;
  padding: 0 0 15px 34px;
}

.page-about .about-flow__item::before {
  content: counter(about-flow, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 2px;
  font-family: var(--fy-font-mono);
  font-size: 12px;
  color: var(--fy-deep-orange);
}

.page-about .about-flow__item::after {
  content: "";
  position: absolute;
  left: 11px;
  top: 20px;
  bottom: 2px;
  width: 1px;
  background: rgba(20, 22, 26, .14);
}

.page-about .about-flow__item:last-child::after {
  display: none;
}

.page-about .about-flow__name {
  display: block;
  font-size: 15px;
  font-weight: 700;
  color: var(--fy-ink);
}

.page-about .about-flow__text {
  display: block;
  margin-top: 4px;
  font-size: 13.5px;
  line-height: 1.78;
  color: var(--fy-slate);
}

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

.page-about .about-team__figure .fy-media__img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
}

.page-about .about-team__figure .fy-media__caption {
  color: var(--fy-slate);
}

/* ============ E 准则与边界 ============ */
.page-about .about-scope {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}

@media (min-width: 760px) {
  .page-about .about-scope {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, .75fr);
    gap: 32px;
  }
}

.page-about .about-scope__col {
  padding-top: 16px;
}

.page-about .about-scope__col--do {
  border-top: 2px solid var(--fy-cyan);
}

.page-about .about-scope__col--dont {
  border-top: 2px solid rgba(246, 241, 231, .24);
}

.page-about .about-scope__title {
  margin: 0 0 14px;
  font-family: var(--fy-font-body);
  font-size: 16px;
  font-weight: 700;
  color: var(--fy-paper);
}

.page-about .about-scope__list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-scope__list li {
  position: relative;
  padding: 9px 0 9px 22px;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--about-dim);
  border-bottom: 1px solid rgba(53, 230, 224, .07);
}

.page-about .about-scope__list li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 19px;
  width: 8px;
  height: 1px;
}

.page-about .about-scope__col--do .about-scope__list li::before {
  background: var(--fy-cyan);
}

.page-about .about-scope__col--dont .about-scope__list li::before {
  background: rgba(246, 241, 231, .4);
}

.page-about .about-note {
  margin-top: clamp(30px, 4vw, 48px);
  padding: clamp(20px, 2.8vw, 30px);
  border: 1px solid var(--about-hair-soft);
  border-radius: var(--fy-radius);
  background: linear-gradient(168deg, rgba(42, 19, 87, .28), rgba(10, 24, 48, .3));
}

.page-about .about-note__title {
  margin: 0 0 12px;
  font-family: var(--fy-font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--fy-paper);
}

.page-about .about-note__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--about-dim);
  max-width: 46em;
}

.page-about .about-note__text a {
  color: var(--fy-cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--fy-edge);
}

.page-about .about-note__text a:hover,
.page-about .about-note__text a:focus-visible {
  color: var(--fy-paper);
  border-bottom-color: var(--fy-cyan);
}

.page-about .about-note__text--quiet {
  margin-top: 14px;
  font-size: 13px;
  color: var(--about-dim-2);
}

/* ============ 窄屏收敛 ============ */
@media (max-width: 559px) {
  .page-about .about-chapter__head {
    grid-template-columns: 30px minmax(0, 1fr);
    column-gap: 12px;
  }

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

  .page-about .about-dossier__body {
    padding-left: 16px;
  }

  .page-about .about-dossier__summary {
    grid-template-columns: 26px minmax(0, 1fr) auto;
    gap: 8px;
    font-size: 14px;
  }

  .page-about .about-lanes__item {
    clip-path: none;
    border-radius: 14px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-axis__link,
  .page-about .about-dossier__summary::after,
  .page-about .about-lanes__link {
    transition: none;
  }

  .page-about .about-axis__link:hover::before,
  .page-about .about-axis__link:focus-visible::before {
    box-shadow: none;
  }
}