.page-about .about-flow {
  display: grid;
  gap: clamp(36px, 6vw, 80px);
  padding-block: clamp(22px, 3.5vw, 44px) clamp(48px, 8vw, 96px);
}

.page-about .crumbs {
  justify-self: start;
}

/* ---------- 首屏 ---------- */
.page-about .about-open {
  display: grid;
  gap: calc(var(--gap) * 1.4);
  align-items: start;
}

.page-about .about-open__copy {
  max-width: 44ch;
}

.page-about .about-open h1 {
  margin: 10px 0 20px;
  font-size: clamp(32px, 6vw, 62px);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: 0.05em;
  color: var(--ink);
}

.page-about .about-open .lead {
  margin: 0 0 16px;
  font-size: clamp(16px, 1.9vw, 19px);
  line-height: 1.8;
  color: var(--ink);
}

.page-about .about-open__note {
  margin: 22px 0 0;
  padding-left: 14px;
  border-left: var(--bw) solid var(--gold);
  font-size: 15px;
  line-height: 1.7;
  color: var(--mid);
}

.page-about .about-open__fig {
  margin: 0;
  border: var(--bw) solid var(--ink);
  box-shadow: var(--hard);
  background: var(--sand);
}

@media (min-width: 880px) {
  .page-about .about-open {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
    gap: calc(var(--gap) * 2);
  }

  .page-about .about-open__copy {
    max-width: none;
    padding-top: 10px;
  }

  .page-about .about-open__fig {
    margin-top: 8px;
  }
}

/* ---------- 阶段带 ---------- */
.page-about .stage-band {
  border-top: var(--bw) solid var(--ink);
  padding-top: clamp(20px, 3vw, 32px);
}

.page-about .stage-band__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: clamp(18px, 2.5vw, 28px);
}

.page-about .stage-band h2 {
  margin: 0;
  font-size: clamp(22px, 3vw, 32px);
  font-weight: 800;
  letter-spacing: 0.05em;
  color: var(--ink);
}

.page-about .stage-band__mark {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.28em;
  color: var(--saffron);
  white-space: nowrap;
}

.page-about .stage-track {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--gap);
}

.page-about .stage {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 20px 18px 16px;
  border: var(--bw) solid var(--ink);
  background: var(--white);
  box-shadow: var(--hard-sm);
  transition: box-shadow 0.16s ease, background-color 0.16s ease;
}

.page-about .stage:nth-child(2) {
  background: var(--sand);
}

.page-about .stage:nth-child(3) {
  background: var(--gold);
}

.page-about .stage:hover,
.page-about .stage:focus-within {
  box-shadow: var(--hard);
}

.page-about .stage__year {
  align-self: flex-start;
  padding: 2px 9px 3px;
  background: var(--ink);
  color: var(--paper);
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.08em;
}

.page-about .stage__name {
  margin: 4px 0 0;
  font-size: 20px;
  font-weight: 800;
  letter-spacing: 0.04em;
  color: var(--ink);
}

.page-about .stage__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink);
}

.page-about .stage__cities {
  margin: auto 0 0;
  padding-top: 12px;
  border-top: 2px solid rgba(19, 26, 44, 0.18);
  font-size: 13px;
  font-weight: 600;
  color: var(--mid);
  transition: color 0.16s ease;
}

.page-about .stage:hover .stage__cities,
.page-about .stage:focus-within .stage__cities {
  color: var(--ink);
}

@media (min-width: 768px) {
  .page-about .stage-track {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 网络 + 数字栏 ---------- */
.page-about .about-split {
  display: grid;
  gap: calc(var(--gap) * 1.5);
}

.page-about .about-split h2,
.page-about .about-quality h2,
.page-about .about-promise h2 {
  margin: 0 0 18px;
  font-size: clamp(24px, 3.4vw, 38px);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: 0.05em;
  color: var(--ink);
}

.page-about .about-split__main p {
  margin: 0 0 14px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink);
}

.page-about .about-split__link {
  margin: 10px 0 0;
}

.page-about .about-split__link a {
  display: inline-block;
  padding-bottom: 2px;
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
  text-decoration: none;
  border-bottom: var(--bw) solid var(--gold);
  transition: background-color 0.16s ease;
}

.page-about .about-split__link a:hover,
.page-about .about-split__link a:focus-visible {
  background: var(--gold);
}

.page-about .about-rail {
  display: grid;
  gap: 14px;
  align-content: start;
  padding-top: 16px;
  border-top: var(--bw) solid var(--sand);
}

.page-about .about-rail__mark {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.3em;
  color: var(--saffron);
  white-space: nowrap;
}

.page-about .rail-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .rail-stat {
  display: grid;
  gap: 4px;
  justify-items: start;
}

.page-about .rail-stat__num {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: clamp(26px, 3.6vw, 34px);
  font-weight: 600;
  line-height: 1;
  letter-spacing: 0.02em;
  padding: 6px 10px 7px;
  background: var(--sand);
  color: var(--ink);
  transition: background-color 0.16s ease;
}

.page-about .rail-stat:hover .rail-stat__num {
  background: var(--gold);
}

.page-about .rail-stat__label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--mid);
}

@media (min-width: 960px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1fr) 264px;
    gap: calc(var(--gap) * 2.5);
    align-items: start;
  }

  .page-about .about-rail {
    grid-template-columns: 24px minmax(0, 1fr);
    gap: 18px;
    padding-top: 0;
    padding-left: 18px;
    border-top: none;
    border-left: var(--bw) solid var(--sand);
  }

  .page-about .about-rail__mark {
    writing-mode: vertical-rl;
    letter-spacing: 0.5em;
    justify-self: start;
  }
}

/* ---------- 团队（深靛段落） ---------- */
.page-about .about-crew {
  background: var(--ink);
  border: var(--bw) solid var(--ink);
  border-top: 8px solid var(--gold);
  padding: clamp(22px, 4vw, 48px);
  color: var(--paper);
}

.page-about .about-crew h2 {
  margin: 0 0 16px;
  font-size: clamp(24px, 3.4vw, 38px);
  font-weight: 800;
  letter-spacing: 0.05em;
  color: var(--paper);
}

.page-about .about-crew__body > p {
  margin: 0 0 18px;
  font-size: 16px;
  line-height: 1.8;
  color: rgba(245, 238, 225, 0.86);
}

.page-about .about-crew__grid {
  display: grid;
  gap: calc(var(--gap) * 1.3);
}

.page-about .about-crew__fig {
  margin: 0;
  border: var(--bw) solid var(--gold);
  background: var(--sand);
}

.page-about .roles {
  list-style: none;
  margin: 0 0 20px;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .role {
  padding: 14px;
  border: 2px solid rgba(245, 238, 225, 0.28);
  background: rgba(255, 253, 248, 0.04);
  transition: border-color 0.16s ease, background-color 0.16s ease;
}

.page-about .role:hover {
  border-color: var(--gold);
  background: rgba(229, 160, 58, 0.12);
}

.page-about .role h3 {
  margin: 0 0 8px;
  font-size: 16px;
  font-weight: 800;
  letter-spacing: 0.06em;
  color: var(--gold);
}

.page-about .role p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: rgba(245, 238, 225, 0.82);
}

.page-about .about-crew__train {
  margin: 0;
  padding: 14px 16px;
  background: rgba(229, 160, 58, 0.16);
  border-left: 5px solid var(--gold);
  font-size: 15px;
  line-height: 1.75;
  color: var(--paper);
}

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

@media (min-width: 920px) {
  .page-about .about-crew__grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: calc(var(--gap) * 2);
    align-items: start;
  }
}

/* ---------- 质量 ---------- */
.page-about .about-quality {
  display: grid;
  gap: calc(var(--gap) * 1.4);
}

.page-about .about-quality__copy > p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink);
}

.page-about .qlist {
  list-style: none;
  margin: 0 0 18px;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .qitem {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr);
  gap: 12px;
  padding: 14px;
  border: 2px solid var(--sand);
  background: var(--white);
  transition: border-color 0.16s ease, box-shadow 0.16s ease;
}

.page-about .qitem:hover {
  border-color: var(--ink);
  box-shadow: var(--hard-sm);
}

.page-about .qitem__k {
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 600;
  line-height: 1;
  color: var(--saffron);
}

.page-about .qitem h3 {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 800;
  letter-spacing: 0.04em;
  color: var(--ink);
}

.page-about .qitem p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--mid);
}

.page-about .about-quality__parts {
  margin: 0;
  padding: 14px 16px;
  background: var(--sand);
  border-left: 5px solid var(--pine);
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink);
}

.page-about .about-quality__fig {
  margin: 0;
  border: var(--bw) solid var(--ink);
  box-shadow: var(--hard);
  background: var(--sand);
}

@media (min-width: 900px) {
  .page-about .about-quality {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: calc(var(--gap) * 2);
    align-items: start;
  }

  .page-about .about-quality__fig {
    margin-top: 6px;
  }
}

/* ---------- 承诺与入口 ---------- */
.page-about .about-promise__ribbon {
  height: 6px;
  margin-bottom: clamp(22px, 3vw, 32px);
  background: linear-gradient(
    90deg,
    var(--sky) 0 20%,
    var(--white) 20% 40%,
    var(--saffron) 40% 60%,
    var(--pine) 60% 80%,
    var(--lany) 80% 100%
  );
}

.page-about .about-promise p {
  margin: 0 0 14px;
  max-width: 68ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink);
}

.page-about .about-cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px 24px;
  margin-top: 14px;
}

.page-about .about-cta__link {
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
  text-decoration: none;
  border-bottom: 2px solid var(--sky);
  padding-bottom: 1px;
  transition: background-color 0.16s ease, border-color 0.16s ease;
}

.page-about .about-cta__link:hover,
.page-about .about-cta__link:focus-visible {
  background: var(--gold);
  border-color: var(--ink);
}