.page-about {
  --about-line: #262a3d;
  --about-line-soft: rgba(139, 92, 246, 0.28);
  --about-pad-y: clamp(44px, 7vw, 88px);
  background: var(--void-black);
  color: var(--cold-white);
  padding-bottom: clamp(40px, 6vw, 80px);
  overflow-x: hidden;
}

/* ---------- 首屏框景 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(20px, 4vw, 36px) 0 clamp(40px, 6vw, 72px);
  border-bottom: 1px solid var(--about-line);
  background:
    radial-gradient(120% 90% at 86% -14%, rgba(139, 92, 246, 0.26), transparent 62%),
    linear-gradient(158deg, rgba(59, 29, 110, 0.34) 0%, transparent 56%);
}

.page-about .about-hero .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  margin: 0 0 clamp(20px, 4vw, 34px);
  padding: 0;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--muted-mist);
}

.page-about .about-hero .breadcrumb__link {
  color: var(--muted-mist);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--ease), border-color var(--ease);
}

.page-about .about-hero .breadcrumb__link:hover,
.page-about .about-hero .breadcrumb__link:focus-visible {
  color: var(--cold-white);
  border-color: var(--racing-orange);
}

.page-about .about-hero .breadcrumb__current {
  color: var(--neon-violet);
  font-family: var(--font-data);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(24px, 4vw, 44px);
  grid-template-columns: 1fr;
  align-items: start;
}

.page-about .about-hero__eyebrow {
  margin: 0 0 14px;
  font-family: var(--font-data);
  font-size: 11px;
  letter-spacing: 0.24em;
  color: var(--signal-lime);
  text-transform: uppercase;
}

.page-about .about-hero__copy h1 {
  margin: 0 0 clamp(16px, 2.4vw, 22px);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.95rem, 6vw, 3.4rem);
  line-height: 1.14;
  letter-spacing: 0.005em;
  color: var(--cold-white);
  max-width: 16em;
}

.page-about .about-hero__lede {
  margin: 0;
  max-width: 38em;
  font-size: clamp(15px, 1.7vw, 17px);
  line-height: 1.85;
  color: var(--cold-white);
  opacity: 0.84;
}

.page-about .about-hero__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: clamp(20px, 3vw, 30px) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-hero__frame {
  position: relative;
  margin: 0;
  padding: 10px;
  background: var(--panel-ink);
  border: 1px solid var(--about-line-soft);
  box-shadow: 0 0 0 1px rgba(7, 7, 12, 0.9), 18px 24px 48px -28px rgba(139, 92, 246, 0.7);
}

.page-about .about-hero__frame::before,
.page-about .about-hero__frame::after {
  content: "";
  position: absolute;
  width: 22px;
  height: 22px;
  border: 1px solid var(--racing-orange);
  pointer-events: none;
}

.page-about .about-hero__frame::before {
  top: -1px;
  left: -1px;
  border-right: 0;
  border-bottom: 0;
}

.page-about .about-hero__frame::after {
  right: -1px;
  bottom: -1px;
  border-left: 0;
  border-top: 0;
}

.page-about .about-hero__frame img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  filter: saturate(0.92) contrast(1.04);
}

.page-about .about-hero__caption {
  margin: 10px 2px 0;
  font-family: var(--font-data);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--muted-mist);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapter {
  position: relative;
  padding: var(--about-pad-y) 0;
  border-bottom: 1px solid var(--about-line);
}

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

.page-about .about-chapter__grid {
  display: grid;
  gap: clamp(14px, 2.4vw, 28px);
  grid-template-columns: 1fr;
}

.page-about .about-chapter__index {
  margin: 0;
  font-family: var(--font-data);
  font-size: clamp(26px, 4vw, 34px);
  line-height: 1;
  letter-spacing: 0.08em;
  color: transparent;
  -webkit-text-stroke: 1px var(--neon-violet);
  position: relative;
  padding-left: 18px;
}

.page-about .about-chapter__index::before {
  content: "";
  position: absolute;
  left: 0;
  top: 2px;
  width: 2px;
  height: calc(100% - 4px);
  background: linear-gradient(180deg, var(--racing-orange), var(--violet-deep));
}

.page-about .about-chapter__title {
  margin: 0 0 clamp(12px, 2vw, 18px);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.35rem, 3.4vw, 2rem);
  line-height: 1.28;
  color: var(--cold-white);
  max-width: 22em;
}

.page-about .about-chapter__lede {
  margin: 0 0 clamp(20px, 3vw, 30px);
  max-width: 40em;
  font-size: clamp(14.5px, 1.6vw, 16.5px);
  line-height: 1.85;
  color: var(--cold-white);
  opacity: 0.78;
}

/* ---------- 长正文 ---------- */
.page-about .about-prose p {
  margin: 0 0 clamp(14px, 2vw, 18px);
  max-width: 40em;
  font-size: clamp(14.5px, 1.6vw, 16.5px);
  line-height: 1.9;
  color: var(--cold-white);
  opacity: 0.9;
}

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

/* ---------- 数字带 ---------- */
.page-about .about-figures {
  display: grid;
  gap: 1px;
  margin: clamp(26px, 4vw, 38px) 0 0;
  grid-template-columns: 1fr;
  background: var(--about-line);
  border: 1px solid var(--about-line);
}

.page-about .about-figures__item {
  background: var(--panel-ink);
  padding: 16px 18px;
}

.page-about .about-figures__item dt {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--muted-mist);
  margin-bottom: 6px;
}

.page-about .about-figures__item dd {
  margin: 0;
  font-family: var(--font-data);
  font-size: clamp(24px, 3.6vw, 32px);
  line-height: 1;
  color: var(--signal-lime);
}

/* ---------- 三道关 ---------- */
.page-about .check-flow {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(18px, 3vw, 26px);
  grid-template-columns: 1fr;
  counter-reset: none;
}

.page-about .check-step {
  position: relative;
  padding: 20px 0 0;
  border-top: 2px solid var(--about-line-soft);
}

.page-about .check-step:nth-child(2) {
  border-top-color: rgba(255, 107, 26, 0.6);
}

.page-about .check-step:nth-child(3) {
  border-top-color: rgba(182, 255, 59, 0.5);
}

.page-about .check-step__no {
  margin: 0 0 10px;
  font-family: var(--font-data);
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--neon-violet);
}

.page-about .check-step__title {
  margin: 0 0 10px;
  font-size: clamp(1rem, 2vw, 1.15rem);
  font-weight: 700;
  line-height: 1.4;
  color: var(--cold-white);
}

.page-about .check-step__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--cold-white);
  opacity: 0.76;
}

/* ---------- 团队 ---------- */
.page-about .crew {
  display: grid;
  gap: clamp(22px, 3.4vw, 36px);
  grid-template-columns: 1fr;
  align-items: start;
}

.page-about .crew__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .crew__group {
  padding: 16px 0;
  border-bottom: 1px dashed var(--about-line);
}

.page-about .crew__group:first-child {
  padding-top: 0;
}

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

.page-about .crew__name {
  margin: 0 0 8px;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--paper-warm);
}

.page-about .crew__name::before {
  content: "";
  display: inline-block;
  width: 8px;
  height: 8px;
  margin-right: 10px;
  background: var(--neon-violet);
  transform: translateY(-1px);
}

.page-about .crew__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--cold-white);
  opacity: 0.76;
}

.page-about .crew__figure {
  margin: 0;
  padding: 8px;
  background: var(--panel-ink);
  border: 1px solid var(--about-line);
}

.page-about .crew__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  filter: saturate(0.85);
}

.page-about .about-network {
  display: grid;
  gap: 1px;
  margin-top: clamp(26px, 4vw, 40px);
  grid-template-columns: 1fr;
  background: var(--about-line);
  border-top: 2px solid var(--racing-orange);
}

.page-about .about-network__item {
  background: linear-gradient(140deg, var(--violet-deep), var(--panel-ink) 72%);
  padding: 18px 18px 20px;
}

.page-about .about-network__num {
  margin: 0 0 8px;
  font-family: var(--font-data);
  font-size: clamp(26px, 4vw, 34px);
  line-height: 1;
  color: var(--cold-white);
}

.page-about .about-network__label {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--cold-white);
  opacity: 0.82;
}

/* ---------- 里程碑时间带 ---------- */
.page-about .about-chapter--timeline {
  background:
    linear-gradient(180deg, rgba(59, 29, 110, 0.22), transparent 42%),
    var(--void-black);
}

.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(22px, 3vw, 28px);
  grid-template-columns: 1fr;
}

.page-about .timeline__node {
  position: relative;
  padding-top: 26px;
  border-top: 1px solid var(--about-line);
  scroll-margin-top: calc(var(--header-h) + 24px);
}

.page-about .timeline__node::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  height: 2px;
  width: 100%;
  background: linear-gradient(90deg, var(--neon-violet), transparent 88%);
}

.page-about .timeline__node::after {
  content: "";
  position: absolute;
  top: -6px;
  left: 0;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--signal-lime);
  box-shadow: 0 0 14px rgba(182, 255, 59, 0.65);
}

.page-about .timeline__year {
  margin: 0 0 10px;
  font-family: var(--font-data);
  font-size: clamp(20px, 2.6vw, 26px);
  line-height: 1;
  letter-spacing: 0.06em;
  color: var(--racing-orange);
}

.page-about .timeline__title {
  margin: 0 0 8px;
  font-size: 15px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--cold-white);
}

.page-about .timeline__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--cold-white);
  opacity: 0.74;
}

.page-about .timeline__figure {
  margin: clamp(26px, 4vw, 40px) 0 0;
  padding: 10px;
  background: var(--panel-ink);
  border: 1px solid var(--about-line-soft);
}

.page-about .timeline__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 2 / 1;
  object-fit: cover;
}

/* ---------- 前进方向 ---------- */
.page-about .forward-links {
  display: grid;
  gap: clamp(14px, 2.4vw, 22px);
  grid-template-columns: 1fr;
  margin-top: clamp(22px, 3.4vw, 34px);
}

.page-about .forward-link {
  display: block;
  padding: 20px 20px 18px;
  text-decoration: none;
  color: inherit;
  background: var(--panel-ink);
  border: 1px solid var(--about-line);
  transition: border-color var(--ease), transform var(--ease), background var(--ease);
}

.page-about .forward-link:hover,
.page-about .forward-link:focus-visible {
  border-color: var(--racing-orange);
  background: #151726;
  transform: translateY(-2px);
}

.page-about .forward-link__idx {
  margin: 0 0 12px;
  font-family: var(--font-data);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--neon-violet);
}

.page-about .forward-link__title {
  margin: 0 0 8px;
  font-size: 16px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--cold-white);
}

.page-about .forward-link__text {
  margin: 0 0 14px;
  font-size: 14px;
  line-height: 1.78;
  color: var(--cold-white);
  opacity: 0.74;
}

.page-about .forward-link__go {
  display: inline-block;
  font-family: var(--font-data);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--racing-orange);
  border-bottom: 1px solid rgba(255, 107, 26, 0.45);
  padding-bottom: 2px;
}

.page-about .about-backtop {
  margin: clamp(26px, 4vw, 38px) 0 0;
}

.page-about .about-backtop a {
  display: inline-block;
  font-family: var(--font-data);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--muted-mist);
  text-decoration: none;
  border: 1px solid var(--about-line);
  padding: 10px 16px;
  transition: color var(--ease), border-color var(--ease);
}

.page-about .about-backtop a:hover,
.page-about .about-backtop a:focus-visible {
  color: var(--cold-white);
  border-color: var(--neon-violet);
}

.page-about a:focus-visible {
  outline: 2px solid var(--racing-orange);
  outline-offset: 3px;
}

/* ---------- 平板 ---------- */
@media (min-width: 700px) {
  .page-about .about-figures,
  .page-about .about-network {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .timeline {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: clamp(22px, 3vw, 30px) clamp(18px, 2.4vw, 28px);
  }

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

/* ---------- 桌面 ---------- */
@media (min-width: 960px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.02fr) minmax(0, 0.98fr);
    gap: clamp(32px, 4vw, 60px);
    align-items: center;
  }

  .page-about .about-chapter__grid {
    grid-template-columns: 148px minmax(0, 1fr);
    gap: clamp(28px, 4vw, 64px);
  }

  .page-about .about-chapter__index {
    position: sticky;
    top: calc(var(--header-h) + 28px);
    font-size: 34px;
  }

  .page-about .check-flow {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: clamp(20px, 2.6vw, 32px);
  }

  .page-about .crew {
    grid-template-columns: minmax(0, 1.06fr) minmax(0, 0.94fr);
  }

  .page-about .timeline {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .forward-links {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .forward-link:nth-child(2) {
    margin-top: 18px;
  }

  .page-about .forward-link:nth-child(3) {
    margin-top: 36px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .forward-link,
  .page-about .forward-link:hover,
  .page-about .forward-link:focus-visible {
    transform: none;
    transition: none;
  }
}