.page-about {
  --about-gutter: 20px;
  --about-radius: 2px;
  background: var(--paper);
  color: var(--stone);
  overflow-x: clip;
}

.page-about .container {
  padding-left: var(--about-gutter);
  padding-right: var(--about-gutter);
}

.page-about .crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  padding: 18px 0 4px;
}

.page-about .crumbs__item {
  color: var(--stone);
}

.page-about .crumbs__item + .crumbs__item::before {
  content: "／";
  margin: 0 7px;
  color: var(--copper);
}

.page-about .crumbs__item a {
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--copper);
  padding-bottom: 1px;
}

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

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  padding-top: 22px;
  padding-bottom: 46px;
}

.page-about .about-hero__title {
  font-family: var(--font-head);
  font-weight: 900;
  letter-spacing: -0.02em;
  color: var(--black);
  font-size: clamp(29px, 7.6vw, 66px);
  line-height: 1.07;
  margin: 10px 0 20px;
}

.page-about .about-hero__aside {
  border-left: 2px solid var(--copper);
  padding-left: 16px;
}

.page-about .about-hero__lede {
  margin: 0 0 14px;
  color: var(--ink);
  font-size: 15px;
  line-height: 1.95;
}

.page-about .about-hero__tail {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.85;
  color: var(--steel);
}

.page-about .about-hero__vnote {
  display: none;
}

/* ---------- 规模数字带 ---------- */

.page-about .about-stats {
  padding: 30px 0;
}

.page-about .about-stats__grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px 18px;
}

.page-about .about-stats__item .datum__key {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--copper);
  margin-bottom: 8px;
}

.page-about .about-stats__item .datum__val {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 6px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(30px, 8vw, 44px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--paper);
  font-variant-numeric: tabular-nums;
}

.page-about .about-stats__item .datum__unit {
  font-family: var(--font-mono);
  font-weight: 400;
  font-size: 11px;
  letter-spacing: 0.04em;
  color: rgba(244, 239, 230, 0.7);
}

/* ---------- 通用标题 ---------- */

.page-about .about-h2 {
  font-family: var(--font-head);
  font-weight: 900;
  letter-spacing: -0.02em;
  color: var(--black);
  font-size: clamp(23px, 5.4vw, 38px);
  line-height: 1.18;
  margin: 8px 0 16px;
}

.page-about .eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--copper);
  border-bottom: 1px solid var(--line-strong);
  padding-bottom: 5px;
}

.page-about p {
  font-size: 15px;
  line-height: 1.95;
  margin: 0 0 14px;
}

.page-about .about-link {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--copper);
  padding-bottom: 3px;
  margin-top: 4px;
}

.page-about .about-link span {
  color: var(--copper);
}

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

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--line-strong);
  border-radius: var(--about-radius);
  background: var(--paper-2);
}

.page-about .about-figure figcaption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.7;
  color: var(--stone);
  border-left: 1px solid var(--copper);
  padding-left: 10px;
}

/* ---------- 起点 ---------- */

.page-about .about-origin {
  padding-top: 44px;
  padding-bottom: 44px;
}

.page-about .about-origin__grid {
  display: grid;
  gap: 28px;
}

.page-about .about-origin__text p:first-of-type {
  color: var(--ink);
}

/* ---------- 时间轴 ---------- */

.page-about .about-tl-section {
  padding-bottom: 44px;
}

.page-about .about-tl-head {
  margin-bottom: 22px;
}

.page-about .about-tl-head .section-head__index {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--copper);
  margin: 0 0 6px;
}

.page-about .about-tl-head .section-head__note {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.8;
  color: var(--steel);
}

.page-about .about-tl-head .section-head__title {
  margin-top: 0;
}

.page-about .about-tl {
  position: relative;
  padding-left: 0;
}

.page-about .about-tl::before {
  content: "";
  position: absolute;
  left: 20px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(to bottom, var(--copper), var(--line-strong));
}

.page-about .about-tl__item {
  position: relative;
  border: 0;
  border-top: 1px solid var(--line);
  background: transparent;
}

.page-about .about-tl__item:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .about-tl__head {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr) 22px;
  align-items: center;
  gap: 10px;
  padding: 16px 0;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-tl__dot {
  justify-self: start;
  width: 13px;
  height: 13px;
  margin-left: 14px;
  border-radius: 50%;
  background: var(--paper);
  border: 2px solid var(--copper);
  position: relative;
  z-index: 1;
}

.page-about .about-tl__item[open] .about-tl__dot {
  background: var(--copper);
}

.page-about .about-tl__title {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 16px;
  line-height: 1.5;
  color: var(--ink);
}

.page-about .about-tl__title b {
  display: inline-block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.04em;
  color: var(--clay);
  margin-right: 10px;
  font-variant-numeric: tabular-nums;
}

.page-about .about-tl__mark {
  justify-self: end;
  width: 12px;
  height: 12px;
  position: relative;
}

.page-about .about-tl__mark::before,
.page-about .about-tl__mark::after {
  content: "";
  position: absolute;
  background: var(--stone);
}

.page-about .about-tl__mark::before {
  left: 0;
  top: 5.5px;
  width: 12px;
  height: 1px;
}

.page-about .about-tl__mark::after {
  left: 5.5px;
  top: 0;
  width: 1px;
  height: 12px;
}

.page-about .about-tl__item[open] .about-tl__mark::after {
  display: none;
}

.page-about .about-tl__body {
  padding: 0 0 20px 50px;
}

.page-about .about-tl__body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.9;
  color: var(--stone);
}

/* ---------- 服务网络 ---------- */

.page-about .about-network {
  padding: 42px 0;
}

.page-about .about-network__grid {
  display: grid;
  gap: 30px;
}

.page-about .about-network__side {
  display: grid;
  gap: 16px;
}

.page-about .about-ring {
  position: relative;
  width: 168px;
  max-width: 100%;
  margin: 0 auto;
}

.page-about .about-ring svg {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .about-ring__track {
  stroke: var(--line-strong);
}

.page-about .about-ring__fill {
  stroke: var(--moss);
}

.page-about .about-ring__num {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
}

.page-about .about-ring__val {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 40px;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--ink);
  font-variant-numeric: tabular-nums;
}

.page-about .about-ring__val small {
  font-size: 17px;
  margin-left: 1px;
  color: var(--moss);
}

.page-about .about-ring__cap {
  margin-top: 6px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.08em;
  color: var(--stone);
}

.page-about .about-network__note {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.85;
  color: var(--steel);
  border-top: 1px solid var(--line-strong);
  padding-top: 14px;
}

/* ---------- 标准与材料 ---------- */

.page-about .about-standard {
  padding-top: 44px;
  padding-bottom: 44px;
}

.page-about .about-standard .section-head__index {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--copper);
  margin: 0 0 6px;
}

.page-about .about-standard .section-head__note {
  margin: 0 0 24px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.8;
  color: var(--steel);
}

.page-about .about-standard .section-head__title {
  margin-top: 0;
}

.page-about .about-standard__grid {
  display: grid;
  gap: 26px;
}

.page-about .about-standard__text p:first-of-type {
  color: var(--ink);
}

.page-about .about-standard__chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 18px 0 14px;
}

.page-about .about-standard__chips .tag {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.04em;
  padding: 6px 10px;
  border: 1px solid currentColor;
  border-radius: var(--about-radius);
  background: var(--paper-2);
}

.page-about .about-standard__chips .tag--base { color: var(--clay); }
.page-about .about-standard__chips .tag--material { color: var(--ink); }
.page-about .about-standard__chips .tag--labor { color: var(--steel); }
.page-about .about-standard__chips .tag--ok { color: var(--moss); }

/* ---------- 重庆 ---------- */

.page-about .about-cq {
  padding-bottom: 46px;
  background:
    linear-gradient(to bottom, transparent 0, transparent 38%, var(--paper-2) 38%, var(--paper-2) 100%);
}

.page-about .about-cq__head {
  padding-top: 8px;
  margin-bottom: 22px;
}

.page-about .about-cq__lede {
  color: var(--ink);
  margin-bottom: 0;
}

.page-about .about-cq__steps {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  gap: 0;
  counter-reset: cqstep;
}

.page-about .about-cq__step {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 4px 12px;
  padding: 16px 0;
  border-top: 1px solid var(--line);
}

.page-about .about-cq__step:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .about-cq__idx {
  grid-row: 1 / span 2;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--copper);
  padding-top: 3px;
}

.page-about .about-cq__step h3 {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 16px;
  color: var(--ink);
}

.page-about .about-cq__step p {
  grid-column: 2;
  margin: 4px 0 0;
  font-size: 14px;
  line-height: 1.88;
  color: var(--stone);
}

.page-about .about-cq__foot {
  margin: 22px 0 0;
  font-family: var(--font-mono);
  font-size: 12.5px;
  line-height: 1.9;
  color: var(--steel);
}

.page-about .about-figure--wide {
  margin-bottom: 4px;
}

/* ---------- 评价与复核 ---------- */

.page-about .about-review {
  padding: 42px 0;
}

.page-about .about-review__grid {
  display: grid;
  gap: 26px;
}

.page-about .about-review__side {
  display: grid;
  gap: 14px;
}

.page-about .about-review__card {
  display: block;
  padding: 18px 20px;
  background: var(--paper-2);
  border: 1px solid var(--line-strong);
  border-left: 3px solid var(--moss);
  border-radius: var(--about-radius);
}

.page-about .about-review__card--line {
  border-left-color: var(--steel);
}

.page-about .about-review__card-key {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--stone);
  margin-bottom: 10px;
}

.page-about .about-review__card-val {
  display: block;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 46px;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--ink);
  font-variant-numeric: tabular-nums;
}

.page-about .about-review__card-val small {
  font-family: var(--font-mono);
  font-weight: 400;
  font-size: 12px;
  color: var(--steel);
  margin-left: 6px;
  letter-spacing: 0.02em;
}

.page-about .about-review__card-note {
  display: block;
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.7;
  color: var(--stone);
}

/* ---------- 结尾 ---------- */

.page-about .about-cta {
  padding-bottom: 56px;
}

.page-about .about-cta__inner {
  display: grid;
  gap: 20px;
  padding: 24px 20px;
  background: var(--ink);
  color: var(--paper);
  border: 1px solid var(--ink-deep);
  border-radius: var(--about-radius);
  box-shadow: var(--shadow-paper);
}

.page-about .about-cta__title {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(21px, 5vw, 30px);
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: var(--paper);
  margin: 0 0 12px;
}

.page-about .about-cta__text p {
  margin: 0;
  font-size: 14px;
  line-height: 1.9;
  color: rgba(244, 239, 230, 0.82);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-cta .btn {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  padding: 11px 16px;
  text-decoration: none;
  border-radius: var(--about-radius);
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.page-about .about-cta .btn--solid {
  background: var(--copper);
  color: var(--black);
  border: 1px solid var(--copper);
}

.page-about .about-cta .btn--line {
  background: transparent;
  color: var(--paper);
  border: 1px solid rgba(244, 239, 230, 0.42);
}

.page-about .about-cta .btn--quiet {
  background: transparent;
  color: rgba(244, 239, 230, 0.78);
  border: 1px solid transparent;
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 桌面 ---------- */

@media (min-width: 760px) {
  .page-about {
    --about-gutter: 32px;
  }

  .page-about .about-stats__grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 24px;
  }

  .page-about .about-hero {
    padding-top: 34px;
    padding-bottom: 58px;
  }

  .page-about .about-hero__grid {
    display: grid;
    grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
    gap: 46px;
    align-items: end;
  }

  .page-about .about-hero__title {
    margin-bottom: 0;
    max-width: 17ch;
  }

  .page-about .about-hero__vnote {
    display: block;
    position: absolute;
    right: 4px;
    top: 42px;
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 0.16em;
    color: var(--copper);
    writing-mode: vertical-rl;
  }

  .page-about .about-origin__grid {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 1fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .about-standard__grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.06fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .about-standard__grid .about-figure {
    order: -1;
  }

  .page-about .about-network__grid {
    grid-template-columns: minmax(0, 1.5fr) minmax(240px, 0.9fr);
    gap: 48px;
    align-items: center;
  }

  .page-about .about-review__grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .about-cq__steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0 32px;
  }

  .page-about .about-cq__step:nth-child(2) ~ .about-cq__step {
    border-top: 1px solid var(--line);
  }

  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 0.9fr);
    align-items: center;
    gap: 32px;
    padding: 32px 34px;
  }

  .page-about .about-cta__actions {
    justify-content: flex-end;
  }
}

@media (min-width: 1024px) {
  .page-about {
    --about-gutter: 48px;
  }

  .page-about .about-tl__head {
    grid-template-columns: 56px minmax(0, 1fr) 24px;
    padding: 18px 0;
  }

  .page-about .about-tl::before {
    left: 28px;
  }

  .page-about .about-tl__dot {
    margin-left: 22px;
  }

  .page-about .about-tl__body {
    padding-left: 66px;
    max-width: 78ch;
  }

  .page-about .about-tl__title {
    font-size: 18px;
  }

  .page-about .about-cq__steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0 26px;
  }

  .page-about .about-cq__step {
    display: block;
    border-top: 1px solid var(--line);
    border-bottom: 0;
  }

  .page-about .about-cq__step:last-child {
    border-bottom: 1px solid var(--line);
  }

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

  .page-about .about-cq__idx {
    display: block;
    margin-bottom: 10px;
  }
}