.page-about {
  --about-railw: 176px;
  --about-hair: rgba(217, 255, 242, .14);
  --about-hair-strong: rgba(217, 255, 242, .26);
  background:
    radial-gradient(1100px 520px at 84% -6%, rgba(47, 240, 200, .09), transparent 62%),
    radial-gradient(760px 460px at 4% 6%, rgba(255, 106, 43, .06), transparent 64%),
    var(--night);
  color: var(--ink);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  padding-top: clamp(1.6rem, 4vw, 3rem);
  padding-bottom: clamp(2rem, 5vw, 3.6rem);
}

.page-about .breadcrumbs {
  margin-bottom: clamp(1.4rem, 3.5vw, 2.6rem);
}

.page-about .breadcrumbs__list {
  display: flex;
  flex-wrap: wrap;
  gap: .45rem;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: .74rem;
  letter-spacing: .08em;
  color: var(--mist);
}

.page-about .breadcrumbs__item + .breadcrumbs__item::before {
  content: "/";
  margin-right: .45rem;
  color: rgba(147, 179, 167, .55);
}

.page-about .breadcrumbs__link {
  color: var(--mist);
  text-decoration: none;
  transition: color var(--dur) var(--ease);
}

.page-about .breadcrumbs__link:hover,
.page-about .breadcrumbs__link:focus-visible {
  color: var(--cyan);
}

.page-about .breadcrumbs__link[aria-current="page"] {
  color: var(--ink);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(1.6rem, 4vw, 3rem);
  align-items: center;
}

.page-about .about-hero__title {
  margin: .85rem 0 1.1rem;
  font-size: clamp(2rem, 5.6vw, 4.15rem);
  font-weight: 200;
  line-height: 1.08;
  letter-spacing: -.015em;
}

.page-about .about-hero__lede {
  margin: 0;
  max-width: 34rem;
  color: var(--mist);
  line-height: 1.85;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: .65rem;
  margin-top: 1.6rem;
}

.page-about .about-hero__visual {
  position: relative;
  height: clamp(238px, 32vw, 400px);
  border: 1px solid var(--about-hair);
  background: linear-gradient(155deg, rgba(11, 52, 40, .92) 0%, rgba(6, 23, 38, .96) 68%);
  clip-path: polygon(var(--cut) 0, 100% 0, 100% calc(100% - var(--cut)), calc(100% - var(--cut)) 100%, 0 100%, 0 var(--cut));
  overflow: hidden;
}

.page-about .about-hero__svg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
}

.page-about .about-hero__cap {
  position: absolute;
  left: 1.1rem;
  right: 1.1rem;
  bottom: .95rem;
  margin: 0;
  font-size: .72rem;
  letter-spacing: .08em;
  color: var(--mist);
  z-index: 2;
}

.page-about .about-figures {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(2rem, 5vw, 3.2rem);
  border: 1px solid var(--about-hair);
  background: var(--about-hair);
}

.page-about .about-fig {
  padding: 1.05rem .95rem 1.15rem;
  background: var(--deep);
}

.page-about .about-fig__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 3.4vw, 2.3rem);
  line-height: 1;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .about-fig__unit {
  font-size: .48em;
  margin-left: .12em;
  color: var(--amber);
}

.page-about .about-fig__label {
  display: block;
  margin-top: .5rem;
  font-size: .78rem;
  line-height: 1.5;
  color: var(--mist);
}

/* ---------- 主体骨架 ---------- */

.page-about .about-body {
  display: grid;
  gap: clamp(1.4rem, 3vw, 2.6rem);
  padding-bottom: clamp(3rem, 8vw, 6rem);
}

.page-about .about-rail {
  min-width: 0;
}

.page-about .index-rail {
  display: flex;
  gap: .4rem;
  margin: 0;
  padding: 0 0 .5rem;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}

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

.page-about .index-rail__link {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: baseline;
  gap: .45rem;
  padding: .48rem .85rem;
  border: 1px solid var(--about-hair);
  border-radius: 999px;
  color: var(--mist);
  text-decoration: none;
  font-size: .78rem;
  letter-spacing: .06em;
  white-space: nowrap;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .index-rail__link .num {
  font-family: var(--font-mono);
  color: var(--cyan);
  font-size: .74rem;
}

.page-about .index-rail__link:hover,
.page-about .index-rail__link:focus-visible {
  color: var(--ink);
  border-color: rgba(47, 240, 200, .45);
  background: rgba(47, 240, 200, .07);
}

.page-about .about-flow {
  min-width: 0;
}

.page-about .about-block {
  scroll-margin-top: 110px;
  padding-block: clamp(1.9rem, 4.4vw, 3.2rem);
  border-top: 1px solid var(--about-hair);
}

.page-about .about-block__head {
  max-width: 46rem;
}

.page-about .about-block__title {
  margin: .6rem 0 .9rem;
  font-size: clamp(1.55rem, 3.6vw, 2.5rem);
  font-weight: 200;
  line-height: 1.16;
  letter-spacing: -.01em;
}

.page-about .about-block__lede {
  margin: 0;
  max-width: 36rem;
  color: var(--mist);
  line-height: 1.85;
}

/* ---------- 时间轴 ---------- */

.page-about .track {
  list-style: none;
  margin: 1.7rem 0 0;
  padding: 0 0 0 1.4rem;
  border-left: 1px solid rgba(47, 240, 200, .3);
  display: grid;
  gap: 1.35rem;
}

.page-about .track__item {
  position: relative;
}

.page-about .track__dot {
  position: absolute;
  left: -1.4rem;
  top: .48rem;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--grass-line);
  transform: translateX(-50%);
  transition: background var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .track__item[aria-current="true"] .track__dot {
  background: var(--orange);
  box-shadow: 0 0 0 5px rgba(255, 106, 43, .16);
}

.page-about .track__label {
  display: inline-block;
  margin-bottom: .28rem;
  font-family: var(--font-mono);
  font-size: .8rem;
  letter-spacing: .1em;
  color: var(--orange);
  font-variant-numeric: tabular-nums;
}

.page-about .track__text {
  margin: 0;
  max-width: 38rem;
  color: var(--mist);
  line-height: 1.8;
}

.page-about .track__text strong {
  color: var(--cyan);
  font-weight: 500;
}

/* ---------- 图片容器 ---------- */

.page-about .about-media {
  position: relative;
  margin: 1.7rem 0 0;
  border: 1px solid var(--about-hair);
  background: linear-gradient(150deg, rgba(11, 52, 40, .6), rgba(6, 23, 38, .8));
  clip-path: polygon(var(--cut) 0, 100% 0, 100% calc(100% - var(--cut)), calc(100% - var(--cut)) 100%, 0 100%, 0 var(--cut));
  overflow: hidden;
}

.page-about .about-media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: 16 / 10;
  object-fit: cover;
}

.page-about .about-media--tall img {
  aspect-ratio: 10 / 7;
}

.page-about .about-media--wide img {
  aspect-ratio: 3 / 2;
}

.page-about .about-media .media-frame__cap {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  margin: 0;
  padding: 2rem 1rem .85rem;
  font-size: .75rem;
  letter-spacing: .04em;
  color: var(--ink);
  background: linear-gradient(to top, rgba(4, 18, 14, .94), rgba(4, 18, 14, 0));
}

/* ---------- 岗位卡片 ---------- */

.page-about .about-roles {
  list-style: none;
  margin: 1.7rem 0 0;
  padding: 0;
  display: grid;
  gap: 1rem;
}

.page-about .role {
  position: relative;
  padding: 1.25rem 1.15rem 1.2rem;
  border: 1px solid var(--about-hair);
  background: linear-gradient(170deg, rgba(11, 52, 40, .88), rgba(6, 23, 38, .9));
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, var(--cut) 100%, 0 calc(100% - var(--cut)));
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .role:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

.page-about .role__no {
  margin: 0 0 .55rem;
  font-family: var(--font-mono);
  font-size: .82rem;
  letter-spacing: .1em;
  color: var(--amber);
}

.page-about .role__title {
  margin: 0 0 .4rem;
  font-size: 1.06rem;
  font-weight: 500;
  color: var(--ink);
}

.page-about .role__desc {
  margin: 0;
  font-size: .88rem;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .role__detail {
  margin: .7rem 0 0;
  font-size: .84rem;
  line-height: 1.75;
  color: rgba(147, 179, 167, .92);
  border-top: 1px dashed rgba(217, 255, 242, .16);
  padding-top: .7rem;
  overflow: hidden;
  transition: max-height var(--dur-slow) var(--ease), opacity var(--dur) var(--ease), margin var(--dur) var(--ease);
}

/* ---------- 六个年份区间 ---------- */

.page-about .filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: .45rem;
  margin-top: 1.6rem;
}

.page-about .filter-chip {
  appearance: none;
  border: 1px solid var(--about-hair);
  background: transparent;
  color: var(--mist);
  border-radius: 999px;
  padding: .42rem .9rem;
  font: inherit;
  font-size: .79rem;
  letter-spacing: .04em;
  cursor: pointer;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .filter-chip:hover {
  color: var(--ink);
  border-color: rgba(47, 240, 200, .42);
}

.page-about .filter-chip:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

.page-about .filter-chip[aria-pressed="true"] {
  background: var(--cyan);
  border-color: var(--cyan);
  color: #04120E;
  font-weight: 500;
}

.page-about .about-eras {
  display: grid;
  gap: 1rem;
  margin-top: 1.5rem;
}

.page-about .about-era {
  padding: 1.15rem 1.1rem 1.2rem;
  border: 1px solid var(--about-hair);
  border-top: 3px solid var(--grass-line);
  background: rgba(6, 23, 38, .72);
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-era:hover {
  transform: translateY(-3px);
  border-top-color: var(--cyan);
  background: rgba(11, 52, 40, .78);
}

.page-about .about-era__range {
  display: inline-block;
  margin: 0 0 .75rem;
  padding-bottom: .35rem;
  font-family: var(--font-mono);
  font-size: 1rem;
  letter-spacing: .05em;
  color: var(--cyan);
  border-bottom: 1px solid rgba(47, 240, 200, .3);
  font-variant-numeric: tabular-nums;
}

.page-about .about-era__text {
  margin: 0;
  font-size: .86rem;
  line-height: 1.78;
  color: var(--mist);
}

/* ---------- 海南 ---------- */

.page-about .about-split {
  display: grid;
  gap: 1.4rem;
  margin-top: 1.6rem;
}

.page-about .about-split .about-media {
  margin: 0;
}

.page-about .about-split__body p {
  margin: 0 0 1rem;
  max-width: 36rem;
  color: var(--mist);
  line-height: 1.85;
}

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

/* ---------- 合作方 ---------- */

.page-about .about-partners {
  list-style: none;
  margin: 1.7rem 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-hair);
  border: 1px solid var(--about-hair);
}

.page-about .partner {
  padding: 1.15rem 1.1rem 1.25rem;
  background: var(--deep);
  transition: background var(--dur) var(--ease);
}

.page-about .partner:hover {
  background: rgba(11, 52, 40, .82);
}

.page-about .partner__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.5rem;
  line-height: 1;
  color: var(--orange);
  font-variant-numeric: tabular-nums;
}

.page-about .partner__title {
  margin: .6rem 0 .45rem;
  font-size: .98rem;
  font-weight: 500;
  color: var(--ink);
}

.page-about .partner__text {
  margin: 0;
  font-size: .84rem;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 加入 ---------- */

.page-about .about-block--join {
  border-top-color: transparent;
}

.page-about .about-join {
  position: relative;
  padding: clamp(1.6rem, 4.5vw, 3rem);
  border: 1px solid var(--about-hair);
  background:
    radial-gradient(680px 320px at 88% 8%, rgba(255, 106, 43, .16), transparent 62%),
    linear-gradient(150deg, rgba(11, 52, 40, .95), rgba(6, 23, 38, .95));
  clip-path: polygon(var(--cut) 0, 100% 0, 100% calc(100% - var(--cut)), calc(100% - var(--cut)) 100%, 0 100%, 0 var(--cut));
}

.page-about .about-join__text {
  margin: 0;
  max-width: 38rem;
  color: var(--mist);
  line-height: 1.85;
}

.page-about .about-join__actions {
  display: flex;
  flex-wrap: wrap;
  gap: .65rem;
  margin-top: 1.6rem;
}

/* ---------- 响应式 ---------- */

@media (min-width: 640px) {
  .page-about .about-figures {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

@media (min-width: 760px) {
  .page-about .about-eras {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.04fr) minmax(0, .96fr);
  }
}

@media (min-width: 900px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
    align-items: center;
  }

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

@media (min-width: 1024px) {
  .page-about .about-body {
    grid-template-columns: var(--about-railw) minmax(0, 1fr);
    align-items: start;
    gap: clamp(2rem, 4vw, 3.6rem);
  }

  .page-about .about-rail {
    position: sticky;
    top: 108px;
  }

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

  .page-about .index-rail__link {
    position: relative;
    display: flex;
    flex-direction: column;
    gap: .18rem;
    border: 0;
    border-radius: 0;
    padding: .62rem 0 .62rem 1.05rem;
    font-size: .8rem;
    background: none;
  }

  .page-about .index-rail__link::before {
    content: "";
    position: absolute;
    left: 0;
    top: 50%;
    width: 9px;
    height: 9px;
    margin-left: -4.5px;
    border-radius: 50%;
    background: var(--grass-line);
    transform: translateY(-50%);
    transition: background var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
  }

  .page-about .index-rail__link:hover::before,
  .page-about .index-rail__link:focus-visible::before {
    background: var(--cyan);
    box-shadow: 0 0 0 4px rgba(47, 240, 200, .14);
  }

  .page-about .index-rail__link:hover,
  .page-about .index-rail__link:focus-visible {
    background: none;
    color: var(--ink);
  }

  .page-about .role:hover {
    transform: translateY(-4px);
    border-color: rgba(47, 240, 200, .45);
    box-shadow: 0 20px 42px -26px rgba(47, 240, 200, .55);
  }

  .page-about .role__detail {
    max-height: 0;
    margin-top: 0;
    padding-top: 0;
    border-top-color: transparent;
    opacity: 0;
  }

  .page-about .role:hover .role__detail,
  .page-about .role:focus-within .role__detail {
    max-height: 12rem;
    margin-top: .7rem;
    padding-top: .7rem;
    border-top-color: rgba(217, 255, 242, .16);
    opacity: 1;
  }
}

@media (min-width: 1200px) {
  .page-about .about-eras {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .role,
  .page-about .about-era,
  .page-about .role__detail,
  .page-about .index-rail__link::before {
    transition: none;
  }

  .page-about .role:hover,
  .page-about .about-era:hover {
    transform: none;
  }
}