.page-about {
  --about-node-gap: clamp(20px, 4vw, 44px);
  --about-rule: rgba(43, 43, 43, .14);
}

/* ============ hero ============ */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(120% 90% at 88% 8%, rgba(184, 121, 31, .18), transparent 58%),
    linear-gradient(180deg, var(--ink) 0%, #0C1826 100%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 4px;
  background: linear-gradient(90deg, var(--cinnabar) 0 12%, var(--bronze) 12% 62%, var(--bronze-dk) 62% 100%);
}

.page-about .about-hero__inner {
  padding-block: clamp(28px, 5vw, 68px) clamp(34px, 6vw, 76px);
}

.page-about .about-hero__crumbs {
  margin-bottom: clamp(20px, 3.6vw, 40px);
  color: var(--ink-muted);
  font-size: 14px;
}

.page-about .about-hero__crumbs a {
  color: var(--ink-text);
  text-decoration: none;
}

.page-about .about-hero__crumbs a:hover,
.page-about .about-hero__crumbs a:focus-visible {
  color: var(--bronze-lt);
}

.page-about .about-hero__crumbs span[aria-current] {
  color: var(--bronze-lt);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(26px, 4vw, 48px);
  grid-template-columns: 1fr;
}

.page-about .about-hero__title {
  margin: 12px 0 0;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: clamp(30px, 5.6vw, 54px);
  line-height: 1.14;
  letter-spacing: -.01em;
  color: var(--white);
  max-width: 20em;
}

.page-about .about-hero__lede {
  margin: 18px 0 0;
  max-width: 44em;
  color: var(--ink-text);
  font-size: clamp(16px, 1.6vw, 18px);
  line-height: 1.75;
}

.page-about .about-hero__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.page-about .about-hero__aside {
  display: grid;
  gap: 2px;
  align-content: start;
  background: var(--ink-2);
  border: 1px solid var(--ink-line);
  border-top: 3px solid var(--bronze);
  padding: clamp(18px, 2.6vw, 28px);
  box-shadow: var(--shadow-2);
}

.page-about .about-hero__stat {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 12px 0;
  border-bottom: 1px dashed var(--ink-line);
}

.page-about .about-hero__stat:last-of-type {
  border-bottom: 0;
}

.page-about .about-hero__statnum {
  color: var(--bronze-lt);
  font-size: clamp(30px, 4.2vw, 42px);
  line-height: 1;
}

.page-about .about-hero__statlabel {
  color: var(--ink-muted);
  font-size: 14px;
  line-height: 1.5;
}

.page-about .about-hero__aside-note {
  margin: 14px 0 0;
  padding-top: 14px;
  border-top: 1px solid var(--ink-line);
  color: var(--ink-text);
  font-size: 13.5px;
  line-height: 1.75;
}

/* ============ 年份索引带 ============ */
.page-about .about-index-band {
  padding-block: clamp(18px, 3vw, 28px);
  border-bottom: 1px solid var(--about-rule);
}

.page-about .about-index {
  display: flex;
  gap: clamp(10px, 2vw, 26px);
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-index li {
  flex: 0 0 auto;
}

.page-about .about-index a {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid var(--line-strong);
  background: var(--card);
  color: var(--text);
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  transition: border-color var(--dur), color var(--dur), transform var(--dur);
}

.page-about .about-index a:hover,
.page-about .about-index a:focus-visible {
  border-color: var(--bronze);
  color: var(--bronze-dk);
  transform: translateY(-2px);
}

.page-about .about-index .num {
  color: var(--bronze);
  font-size: 16px;
}

/* ============ 章节头 ============ */
.page-about .about-head {
  max-width: 62ch;
  margin-bottom: clamp(26px, 4vw, 48px);
}

.page-about .about-head--wide {
  max-width: none;
}

.page-about .about-head .section-lede {
  margin-top: 14px;
}

.page-about .about-head a {
  color: var(--bronze-dk);
  text-underline-offset: 3px;
}

/* ============ 时间轴 ============ */
.page-about .about-timeline {
  position: relative;
}

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

.page-about .about-timeline__list {
  margin: 0;
  padding: 0 0 0 clamp(18px, 3vw, 26px);
  list-style: none;
  border-left: 2px solid var(--about-rule);
}

.page-about .about-node {
  position: relative;
  padding-bottom: var(--about-node-gap);
  margin-bottom: var(--about-node-gap);
  border-bottom: 1px dashed var(--about-rule);
}

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

.page-about .about-node::before {
  content: "";
  position: absolute;
  left: calc(-1 * clamp(18px, 3vw, 26px) - 7px);
  top: 12px;
  width: 12px;
  height: 12px;
  background: var(--card);
  border: 3px solid var(--bronze);
  border-radius: 50%;
}

.page-about .about-node:target::before {
  border-color: var(--cinnabar);
  box-shadow: 0 0 0 5px rgba(192, 67, 43, .16);
}

.page-about .about-node:target {
  background: linear-gradient(90deg, rgba(184, 121, 31, .07), transparent 62%);
}

.page-about .about-node__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}

.page-about .about-node__year {
  font-size: clamp(28px, 4.6vw, 44px);
  line-height: 1;
  color: var(--bronze);
  letter-spacing: -.02em;
}

.page-about .about-node__title {
  margin: 0 0 12px;
  font-family: var(--font-sans);
  font-weight: 800;
  font-size: clamp(19px, 2.2vw, 24px);
  line-height: 1.35;
  color: var(--text);
}

.page-about .about-node__body p {
  margin: 0 0 12px;
  max-width: 58ch;
  font-size: 16px;
  line-height: 1.75;
  color: var(--text);
}

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

.page-about .about-node__body a {
  color: var(--bronze-dk);
  text-underline-offset: 3px;
}

.page-about .about-node__figure {
  margin-top: 20px;
  max-width: 520px;
}

.page-about .about-points {
  margin: 6px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 8px;
  max-width: 58ch;
}

.page-about .about-points li {
  position: relative;
  padding-left: 22px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--text);
}

.page-about .about-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .62em;
  width: 10px;
  height: 2px;
  background: var(--cinnabar);
}

/* ============ 原料来源 ============ */
.page-about .about-source {
  border-top: 1px solid var(--ink-line);
}

.page-about .about-source__inner {
  display: grid;
  gap: clamp(24px, 4vw, 46px);
  align-items: start;
}

.page-about .about-source__copy .section-title {
  margin-top: 12px;
}

.page-about .about-source__copy p {
  margin: 14px 0 0;
  max-width: 58ch;
  color: var(--ink-text);
  font-size: 16px;
  line-height: 1.78;
}

.page-about .about-facts {
  display: grid;
  gap: 1px;
  margin: clamp(22px, 3vw, 32px) 0 0;
  background: var(--ink-line);
  border: 1px solid var(--ink-line);
}

.page-about .about-facts__item {
  display: grid;
  grid-template-columns: 1fr;
  gap: 4px;
  padding: 14px 16px;
  background: var(--ink-2);
}

.page-about .about-facts dt {
  color: var(--ink-muted);
  font-size: 13px;
  letter-spacing: .04em;
}

.page-about .about-facts dd {
  margin: 0;
  color: var(--white);
  font-size: 15.5px;
  line-height: 1.6;
}

.page-about .about-facts .num {
  color: var(--bronze-lt);
  font-size: 22px;
}

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

/* ============ 服务网络 ============ */
.page-about .about-network__grid {
  display: grid;
  gap: clamp(22px, 3.4vw, 40px);
}

.page-about .about-network__map {
  background: var(--card);
  border: 1px solid var(--line-strong);
  border-left: 4px solid var(--bronze);
  padding: clamp(18px, 2.6vw, 28px);
  box-shadow: var(--shadow-1);
}

.page-about .about-network__maptitle {
  margin: 0 0 14px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .12em;
  color: var(--muted);
  text-transform: uppercase;
}

.page-about .about-network__points {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 1px;
  background: var(--line);
}

.page-about .about-network__points li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 12px 14px;
  background: var(--card);
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
  transition: background var(--dur), color var(--dur);
}

.page-about .about-network__points li:hover {
  background: #EFE9E0;
  color: var(--bronze-dk);
}

.page-about .about-network__points .num {
  color: var(--bronze);
  font-size: 15px;
}

.page-about .about-network__note {
  margin: 16px 0 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .about-subtitle {
  margin: 0 0 12px;
  font-family: var(--font-sans);
  font-weight: 800;
  font-size: clamp(17px, 1.9vw, 20px);
  color: var(--text);
}

.page-about .about-network__team p {
  margin: 0 0 12px;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.78;
  color: var(--text);
}

.page-about .about-network__stamp {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-top: 22px;
  padding-top: 20px;
  border-top: 1px dashed var(--line-strong);
}

.page-about .about-stamp {
  width: 84px;
  height: 84px;
  flex: 0 0 auto;
}

.page-about .about-network__stamp p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
  max-width: 24ch;
}

/* ============ 质保 ============ */
.page-about .about-quality__inner {
  display: grid;
  gap: clamp(24px, 4vw, 48px);
}

.page-about .about-quality__left .section-title {
  margin-top: 12px;
}

.page-about .about-quality__left > p {
  margin: 14px 0 0;
  max-width: 56ch;
  font-size: 16px;
  line-height: 1.78;
  color: var(--text);
}

.page-about .about-quality__figure {
  margin: 24px 0 0;
}

.page-about .about-warranty {
  display: grid;
  gap: 1px;
  background: var(--line-strong);
  border: 1px solid var(--line-strong);
}

.page-about .about-warranty__row {
  display: flex;
  align-items: center;
  gap: 18px;
  padding: clamp(16px, 2.4vw, 22px);
  background: var(--card);
  transition: background var(--dur);
}

.page-about .about-warranty__row:hover {
  background: #FFFFFF;
}

.page-about .about-warranty__num {
  color: var(--cinnabar);
  font-size: clamp(34px, 5vw, 48px);
  line-height: 1;
  flex: 0 0 auto;
}

.page-about .about-warranty__name {
  margin: 0;
  font-size: 16px;
  font-weight: 700;
  color: var(--text);
}

.page-about .about-warranty__desc {
  margin: 4px 0 0;
  font-size: 14px;
  line-height: 1.65;
  color: var(--muted);
}

.page-about .about-success {
  margin-top: clamp(24px, 3.4vw, 38px);
  padding: clamp(18px, 2.6vw, 26px);
  background: var(--paper);
  border: 1px solid var(--line);
  border-top: 3px solid var(--cinnabar);
}

.page-about .about-success p {
  margin: 0 0 12px;
  max-width: 60ch;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--text);
}

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

.page-about .about-success a {
  color: var(--bronze-dk);
  text-underline-offset: 3px;
}

/* ============ CTA ============ */
.page-about .about-cta {
  border-top: 3px solid var(--bronze);
}

.page-about .about-cta__inner {
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  align-items: center;
}

.page-about .about-cta__kicker {
  color: var(--bronze-lt);
}

.page-about .about-cta__title {
  margin: 12px 0 0;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: clamp(22px, 3vw, 32px);
  line-height: 1.28;
  color: var(--white);
  max-width: 26em;
}

.page-about .about-cta__text p:not(.kicker) {
  margin: 14px 0 0;
  max-width: 46ch;
  color: var(--ink-text);
  font-size: 16px;
  line-height: 1.75;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ============ 响应式 ============ */
@media (min-width: 600px) {
  .page-about .about-facts__item {
    grid-template-columns: 11ch 1fr;
    align-items: baseline;
  }
}

@media (min-width: 860px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(280px, .95fr);
    align-items: start;
  }

  .page-about .about-source__inner {
    grid-template-columns: minmax(0, 1.15fr) minmax(300px, .85fr);
  }

  .page-about .about-network__grid {
    grid-template-columns: minmax(280px, .8fr) minmax(0, 1.2fr);
  }

  .page-about .about-quality__inner {
    grid-template-columns: minmax(0, 1.1fr) minmax(320px, .9fr);
  }

  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 1.5fr) auto;
  }
}

@media (min-width: 1024px) {
  .page-about .about-timeline {
    display: grid;
    grid-template-columns: 220px minmax(0, 1fr);
    gap: clamp(28px, 4vw, 56px);
    align-items: start;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 108px;
    padding: 20px 18px;
    background: var(--paper);
    border: 1px solid var(--line);
    border-left: 3px solid var(--bronze);
  }

  .page-about .about-rail__title {
    margin: 0 0 12px;
    font-size: 12px;
    font-weight: 700;
    letter-spacing: .14em;
    color: var(--muted);
  }

  .page-about .about-rail__list {
    margin: 0;
    padding: 0;
    list-style: none;
    display: grid;
    gap: 2px;
  }

  .page-about .about-rail__list a {
    display: block;
    padding: 8px 10px;
    color: var(--text);
    font-size: 14px;
    font-weight: 600;
    text-decoration: none;
    border-left: 2px solid transparent;
    transition: border-color var(--dur), color var(--dur), background var(--dur);
  }

  .page-about .about-rail__list a:hover,
  .page-about .about-rail__list a:focus-visible {
    border-left-color: var(--bronze);
    background: rgba(184, 121, 31, .1);
    color: var(--bronze-dk);
  }

  .page-about .about-node__figure {
    max-width: 640px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index a,
  .page-about .about-warranty__row,
  .page-about .about-network__points li,
  .page-about .about-rail__list a {
    transition: none;
  }

  .page-about .about-index a:hover,
  .page-about .about-index a:focus-visible {
    transform: none;
  }
}

</main>