.page-about {
  --about-shadow: 8px 8px 0 var(--ink);
  --about-shadow-tight: 4px 4px 0 var(--ink);
  --about-line: rgba(23, 17, 14, 0.16);
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding-top: 18px;
  background:
    radial-gradient(circle at 86% -12%, var(--danxia-soft) 0%, rgba(232, 196, 180, 0) 48%),
    var(--paper);
}

.page-about .about-hero__inner {
  display: grid;
  gap: 18px;
  padding-bottom: 44px;
}

.page-about .about-hero__title {
  margin: 0;
  font-size: clamp(34px, 8.4vw, 76px);
  line-height: 1.04;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--ink);
  text-wrap: balance;
}

.page-about .about-hero__mark {
  display: inline-block;
  background: var(--danxia);
  color: var(--paper);
  padding: 0.02em 0.18em 0.1em;
  -webkit-box-decoration-break: clone;
  box-decoration-break: clone;
}

.page-about .about-hero__lead {
  margin: 0;
  max-width: 42em;
  padding-left: 16px;
  border-left: 4px solid var(--danxia);
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink);
}

.page-about .about-hero__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 4px;
}

.page-about .about-hero__strip {
  background: var(--danxia);
  border-top: var(--rule) solid var(--ink);
  border-bottom: var(--rule) solid var(--ink);
  color: var(--paper);
  padding: 22px 0;
}

.page-about .about-hero__strip-grid {
  display: grid;
  gap: 18px;
}

.page-about .about-strip__item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  border-left: 3px solid var(--gold);
  padding-left: 12px;
}

.page-about .about-strip__num {
  font-family: var(--font-mono);
  font-size: 28px;
  font-weight: 800;
  line-height: 1;
  color: var(--gold);
}

.page-about .about-strip__label {
  font-size: 13px;
  line-height: 1.5;
  letter-spacing: 0.03em;
  color: rgba(246, 241, 231, 0.88);
}

/* ---------- 阶段轨道 ---------- */
.page-about .about-rail {
  position: sticky;
  top: var(--bar-h);
  z-index: 6;
  background: var(--pine);
  border-top: var(--rule) solid var(--ink);
  border-bottom: var(--rule) solid var(--ink);
}

.page-about .about-rail__inner {
  display: flex;
  align-items: center;
  gap: 12px;
  padding-top: 10px;
  padding-bottom: 10px;
}

.page-about .about-rail__label {
  flex: none;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--signal);
  padding-right: 12px;
  border-right: 1px solid rgba(246, 241, 231, 0.28);
}

.page-about .about-rail__list {
  display: flex;
  gap: 6px;
  margin: 0;
  padding: 0 2px 2px 0;
  list-style: none;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-rail__list a {
  display: block;
  white-space: nowrap;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.2;
  padding: 5px 9px;
  color: var(--mist);
  text-decoration: none;
  border: 2px solid transparent;
  transition: border-color 140ms ease-out, color 140ms ease-out, background-color 140ms ease-out;
}

.page-about .about-rail__list a:hover,
.page-about .about-rail__list a:focus-visible {
  border-color: var(--signal);
  color: var(--signal);
  background: rgba(201, 242, 75, 0.08);
}

/* ---------- 时间轴 ---------- */
.page-about .about-body {
  padding-top: 44px;
  padding-bottom: 56px;
}

.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 34px;
}

.page-about .about-stage {
  display: grid;
  gap: 10px;
  scroll-margin-top: calc(var(--bar-h) + 72px);
}

.page-about .about-stage__mark {
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.page-about .about-stage__no {
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 800;
  line-height: 1;
  color: var(--danxia);
}

.page-about .about-stage__era {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--sand);
}

.page-about .about-stage__card {
  position: relative;
  background: var(--paper);
  border: var(--rule) solid var(--ink);
  box-shadow: var(--about-shadow);
  padding: 30px 20px 22px;
  transition: transform 160ms ease-out, box-shadow 160ms ease-out, border-color 160ms ease-out;
}

.page-about .about-stage__card:hover {
  transform: translate(2px, 2px);
  box-shadow: var(--about-shadow-tight);
  border-color: var(--danxia);
}

.page-about .about-stage__tag {
  position: absolute;
  top: -14px;
  left: 18px;
  font-family: var(--font-mono);
  letter-spacing: 0.06em;
}

.page-about .about-stage__title {
  margin: 6px 0 0;
  font-size: clamp(21px, 3.4vw, 30px);
  line-height: 1.28;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about .about-stage__text {
  margin: 14px 0 0;
  max-width: 40em;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink);
}

.page-about .about-stage__figure {
  margin: 22px 0 0;
  border: 2px solid var(--ink);
  background: var(--mist);
  overflow: hidden;
}

.page-about .about-stage__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-stage__cap {
  margin: 0;
  padding: 10px 12px;
  border-top: 2px solid var(--ink);
  background: var(--paper);
  font-size: 13px;
  line-height: 1.6;
  color: var(--sand);
}

.page-about .about-stage__stats {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 22px 0 0;
  padding: 18px 0 0;
  list-style: none;
  border-top: 2px dashed var(--danxia-soft);
}

.page-about .about-stage__stat {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding: 5px 10px;
  border: 2px solid var(--ink);
  background: var(--mist);
  font-size: 13px;
  line-height: 1.5;
  color: var(--ink);
}

.page-about .about-stage__stat .yk-num {
  font-family: var(--font-mono);
  font-weight: 800;
  font-size: 14px;
  color: var(--danxia);
}

/* ---------- 状态图例 ---------- */
.page-about .about-legend {
  margin: 24px 0 0;
  padding: 16px 14px;
  border: 2px solid var(--ink);
  background: var(--paper);
}

.page-about .about-legend svg {
  display: block;
  width: 100%;
  max-width: 420px;
  height: auto;
}

.page-about .about-legend__list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  margin: 14px 0 0;
  padding: 0;
  font-size: 13px;
  line-height: 1.6;
  color: var(--ink);
}

.page-about .about-legend__list li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.page-about .about-legend__dot {
  flex: none;
  display: inline-block;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  border: 3px solid var(--ink);
}

.page-about .about-legend__dot--draft {
  background: var(--paper);
}

.page-about .about-legend__dot--checked {
  background: var(--gold);
}

.page-about .about-legend__dot--live {
  background: var(--signal);
}

/* ---------- 岗位分工 ---------- */
.page-about .about-roles {
  list-style: none;
  display: grid;
  gap: 14px;
  margin: 24px 0 0;
  padding: 0;
}

.page-about .about-role {
  border: 2px solid var(--ink);
  border-left-width: 6px;
  background: var(--mist);
  padding: 16px 14px;
  transition: border-color 160ms ease-out, background-color 160ms ease-out, transform 160ms ease-out;
}

.page-about .about-role:hover,
.page-about .about-role:focus-within,
.page-about .about-role:focus {
  border-color: var(--signal);
  background: var(--paper);
  transform: translateY(-2px);
  outline: none;
}

.page-about .about-role__name {
  display: block;
  margin-bottom: 8px;
  font-size: 16px;
  font-weight: 800;
  color: var(--ink);
}

.page-about .about-role__duties {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--ink);
}

/* ---------- 成果数字 ---------- */
.page-about .about-figures {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin: 24px 0 0;
  padding: 0;
}

.page-about .about-figure {
  border: 2px solid var(--ink);
  background: var(--danxia);
  color: var(--paper);
  padding: 16px 12px;
}

.page-about .about-figure:nth-child(even) {
  background: var(--pine);
}

.page-about .about-figure__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 28px;
  font-weight: 800;
  line-height: 1;
  color: var(--gold);
}

.page-about .about-figure__label {
  display: block;
  margin-top: 8px;
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--paper);
}

.page-about .about-deliver {
  list-style: none;
  display: grid;
  gap: 12px;
  margin: 22px 0 0;
  padding: 0;
}

.page-about .about-deliver li {
  padding: 2px 0 2px 14px;
  border-left: 4px solid var(--grass);
  font-size: 15px;
  line-height: 1.78;
  color: var(--ink);
}

.page-about .about-deliver strong {
  font-weight: 800;
  color: var(--danxia);
}

/* ---------- 结尾入口 ---------- */
.page-about .about-next {
  margin-top: 56px;
  padding: 30px 22px;
  background: var(--pine);
  color: var(--paper);
  border: var(--rule) solid var(--ink);
  box-shadow: var(--about-shadow);
}

.page-about .about-next__title {
  margin: 0;
  font-size: clamp(22px, 3.6vw, 32px);
  line-height: 1.3;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-next__text {
  margin: 14px 0 0;
  max-width: 40em;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .about-next__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

.page-about .about-next__back {
  margin: 22px 0 0;
  padding-top: 18px;
  border-top: 1px solid rgba(246, 241, 231, 0.24);
  font-family: var(--font-mono);
  font-size: 13px;
}

.page-about .about-next__back a {
  color: var(--signal);
  text-decoration: underline;
  text-underline-offset: 4px;
}

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

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-hero__strip-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
  }

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

  .page-about .about-stage__card {
    padding: 34px 30px 26px;
  }
}

@media (min-width: 720px) {
  .page-about .about-hero__lead {
    font-size: 17px;
  }

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

  .page-about .about-next {
    padding: 40px 36px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding-top: 26px;
  }

  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1fr);
    padding-bottom: 56px;
  }

  .page-about .about-timeline {
    gap: 40px;
  }

  .page-about .about-stage {
    grid-template-columns: 176px minmax(0, 1fr);
    gap: 34px;
  }

  .page-about .about-stage__mark {
    display: block;
    position: relative;
    padding: 6px 0 0 30px;
  }

  .page-about .about-stage__mark::before {
    content: "";
    position: absolute;
    left: 7px;
    top: 30px;
    bottom: -42px;
    width: 2px;
    background: var(--danxia-soft);
  }

  .page-about .about-stage:last-child .about-stage__mark::before {
    display: none;
  }

  .page-about .about-stage__mark::after {
    content: "";
    position: absolute;
    left: 0;
    top: 6px;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--gold);
    border: 3px solid var(--ink);
  }

  .page-about .about-stage__no {
    display: block;
    font-size: 34px;
  }

  .page-about .about-stage__era {
    display: block;
    margin-top: 10px;
  }

  .page-about .about-body {
    padding-top: 56px;
  }
}

@media (min-width: 1080px) {
  .page-about .about-roles {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}