.page-about {
  --about-rule: 2px;
  --about-mark: rgba(232, 68, 43, .08);
  --about-frost: rgba(79, 168, 216, .16);
  display: block;
  padding: 0 20px;
  background: var(--ph-cream);
  color: var(--ph-ink);
  font-family: var(--ph-font-body);
  overflow-x: clip;
}

.page-about > * {
  max-width: var(--ph-wrap);
  margin-inline: auto;
}

@media (min-width: 768px) {
  .page-about {
    padding: 0 32px;
  }
}

/* ---------- 面包屑 ---------- */

.page-about .about-crumb {
  padding-top: 26px;
}

.page-about .about-crumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--ph-rock);
}

.page-about .about-crumb__list li[aria-current] {
  color: var(--ph-ink);
  font-weight: 700;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(34px, 6vw, 74px) 0 clamp(30px, 5vw, 56px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -14%;
  right: -18%;
  width: min(620px, 68vw);
  aspect-ratio: 1 / 1;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(38deg, var(--about-frost) 0 1px, transparent 1px 24px),
    repeating-linear-gradient(-26deg, rgba(200, 154, 60, .13) 0 1px, transparent 1px 34px);
  z-index: 0;
}

.page-about .about-hero > * {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__label {
  display: inline-block;
}

.page-about .about-hero__title {
  margin: 16px 0 0;
  max-width: 15em;
  font-family: var(--ph-font-display);
  font-weight: 900;
  font-size: clamp(32px, 6.2vw, 74px);
  line-height: 1.05;
  letter-spacing: -.02em;
  color: var(--ph-ink);
}

.page-about .about-hero__title::after {
  content: "";
  display: block;
  width: clamp(64px, 12vw, 112px);
  height: 6px;
  margin-top: clamp(16px, 3vw, 24px);
  background: linear-gradient(90deg, var(--ph-flame) 0%, var(--ph-gold) 58%, var(--ph-ice) 100%);
}

.page-about .about-hero__lead {
  margin: 24px 0 0;
  max-width: 40em;
  font-size: 16.5px;
  line-height: 1.85;
  color: var(--ph-rock);
}

/* 数据带 */

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 2px;
  margin: 38px 0 0;
  padding: 0;
  list-style: none;
  border: var(--about-rule) solid var(--ph-ink);
  background: var(--ph-ink);
  box-shadow: var(--ph-hard);
}

.page-about .about-stats__item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 16px 16px 20px;
  background: var(--ph-cream);
}

.page-about .about-stats__num {
  font-family: var(--ph-font-mono);
  font-size: clamp(26px, 4vw, 38px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--ph-ink);
}

.page-about .about-stats__label {
  font-size: 12.5px;
  letter-spacing: .08em;
  color: var(--ph-rock);
}

@media (min-width: 760px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 主体两栏 ---------- */

.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 34px;
  padding: clamp(40px, 6vw, 72px) 0 clamp(24px, 4vw, 40px);
}

@media (min-width: 980px) {
  .page-about .about-body {
    grid-template-columns: minmax(0, 3fr) minmax(0, 7fr);
    gap: 0 50px;
  }
}

/* 左侧展线 */

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

.page-about .about-rail__nav {
  display: flex;
  gap: 8px;
  padding-bottom: 8px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-rail__node {
  display: grid;
  grid-template-columns: auto 1fr;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
  padding: 11px 14px;
  border: var(--about-rule) solid transparent;
  border-left: 3px solid var(--ph-clay);
  background: transparent;
  color: var(--ph-rock);
  text-decoration: none;
  transition: background .2s var(--ph-ease), color .2s var(--ph-ease),
              border-color .2s var(--ph-ease), transform .2s var(--ph-ease);
}

.page-about .about-rail__num {
  font-family: var(--ph-font-mono);
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--ph-gold);
}

.page-about .about-rail__text {
  display: block;
  min-width: 0;
}

.page-about .about-rail__label {
  display: block;
  font-family: var(--ph-font-display);
  font-weight: 800;
  font-size: 15px;
  letter-spacing: .02em;
  white-space: nowrap;
}

.page-about .about-rail__meta {
  display: block;
  margin-top: 2px;
  font-family: var(--ph-font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--ph-rock);
  white-space: nowrap;
}

.page-about .about-rail__node:hover,
.page-about .about-rail__node:focus-visible {
  background: var(--ph-cream-2);
  color: var(--ph-ink);
  transform: translateX(3px);
}

.page-about:has(#chapter-01:target) .about-rail__node[href="#chapter-01"],
.page-about:has(#chapter-02:target) .about-rail__node[href="#chapter-02"],
.page-about:has(#chapter-03:target) .about-rail__node[href="#chapter-03"],
.page-about:has(#chapter-04:target) .about-rail__node[href="#chapter-04"],
.page-about:has(#chapter-05:target) .about-rail__node[href="#chapter-05"] {
  background: #FBE7E0;
  border-color: var(--ph-flame);
  border-left-color: var(--ph-flame);
  color: var(--ph-flame-deep);
  transform: translateX(4px);
}

@media (min-width: 980px) {
  .page-about .about-rail__nav {
    position: sticky;
    top: 108px;
    flex-direction: column;
    gap: 0;
    padding-bottom: 0;
    overflow: visible;
  }

  .page-about .about-rail__node {
    width: 100%;
    padding: 14px 16px;
  }

  .page-about .about-rail__node + .about-rail__node {
    margin-top: 4px;
  }
}

/* ---------- 章节 ---------- */

.page-about .about-chapters {
  display: flex;
  flex-direction: column;
  gap: clamp(48px, 7vw, 84px);
  min-width: 0;
}

.page-about .about-ch {
  min-width: 0;
  scroll-margin-top: 120px;
}

.page-about .about-ch__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
  padding-bottom: 14px;
  border-bottom: 3px solid var(--ph-ink);
}

.page-about .about-ch__num {
  font-family: var(--ph-font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--ph-flame-deep);
}

.page-about .about-ch__title {
  flex: 1 1 12em;
  min-width: 0;
  margin: 0;
  font-family: var(--ph-font-display);
  font-weight: 900;
  font-size: clamp(21px, 3vw, 32px);
  line-height: 1.28;
  letter-spacing: -.01em;
  color: var(--ph-ink);
}

.page-about .about-ch__tag {
  font-family: var(--ph-font-mono);
  font-size: 11.5px;
  letter-spacing: .1em;
  color: var(--ph-rock);
  white-space: nowrap;
}

.page-about .about-ch__body {
  margin-top: 24px;
  font-size: 16px;
  line-height: 1.82;
  color: var(--ph-rock);
}

.page-about .about-ch__body p {
  margin: 0 0 16px;
  max-width: 40em;
}

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

/* 说明牌式引用块 */

.page-about .about-note {
  margin: 30px 0 0;
  padding: 20px 22px;
  max-width: 42em;
  border: var(--about-rule) solid var(--ph-ink);
  border-left: 8px solid var(--ph-ice);
  background: var(--ph-cream-2);
  box-shadow: var(--ph-hard-sm);
}

.page-about .about-note__tag {
  display: inline-block;
  margin-bottom: 10px;
  font-family: var(--ph-font-mono);
  font-size: 11.5px;
  letter-spacing: .14em;
  color: var(--ph-flame-deep);
}

.page-about .about-note__body {
  margin: 0;
  font-size: 15px;
  line-height: 1.82;
  color: var(--ph-ink);
}

/* ---------- 团队四组 ---------- */

.page-about .about-teams {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0 28px;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-teams__item {
  padding: 16px 0 18px;
  border-top: var(--about-rule) solid var(--ph-ink);
}

.page-about .about-teams__name {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin: 0;
  font-family: var(--ph-font-display);
  font-weight: 800;
  font-size: 16.5px;
  letter-spacing: .01em;
  color: var(--ph-ink);
}

.page-about .about-teams__idx {
  font-family: var(--ph-font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--ph-flame);
  letter-spacing: .1em;
}

.page-about .about-teams__desc {
  margin: 8px 0 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--ph-rock);
}

@media (min-width: 720px) {
  .page-about .about-teams {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ---------- 流程步骤 ---------- */

.page-about .about-steps {
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
  counter-reset: about-step;
  border-top: var(--about-rule) solid var(--ph-ink);
}

.page-about .about-steps__item {
  position: relative;
  padding: 20px 0 20px 62px;
  border-bottom: var(--about-rule) solid var(--ph-cream-2);
  counter-increment: about-step;
}

.page-about .about-steps__item::before {
  content: "0" counter(about-step);
  position: absolute;
  left: 0;
  top: 22px;
  padding: 3px 8px;
  font-family: var(--ph-font-mono);
  font-size: 12px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: .06em;
  color: var(--ph-cream);
  background: var(--ph-flame-deep);
  border: var(--about-rule) solid var(--ph-ink);
}

.page-about .about-steps__name {
  margin: 0;
  font-family: var(--ph-font-display);
  font-weight: 800;
  font-size: 16px;
  color: var(--ph-ink);
}

.page-about .about-steps__desc {
  margin: 7px 0 0;
  max-width: 38em;
  font-size: 15px;
  line-height: 1.78;
  color: var(--ph-rock);
}

/* ---------- 图文分栏与图片框 ---------- */

.page-about .about-ch__split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
  align-items: start;
}

@media (min-width: 1180px) {
  .page-about .about-ch__split {
    grid-template-columns: minmax(0, 34%) minmax(0, 1fr);
    gap: 30px;
  }
}

.page-about .about-fig {
  position: relative;
  margin: 0;
  border: var(--about-rule) solid var(--ph-ink);
  background: var(--ph-night);
  box-shadow: var(--ph-hard);
  overflow: hidden;
  transition: transform .24s var(--ph-ease), box-shadow .24s var(--ph-ease);
}

.page-about .about-fig img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 14 / 9;
  object-fit: cover;
}

.page-about .about-fig--cut img {
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 30px), calc(100% - 30px) 100%, 0 100%);
}

.page-about .about-fig--sq img {
  aspect-ratio: 1 / 1;
}

.page-about .about-fig__cap {
  display: block;
  padding: 10px 14px;
  font-size: 12.5px;
  line-height: 1.6;
  letter-spacing: .03em;
  color: var(--ph-cream);
  background: var(--ph-night);
}

.page-about .about-fig:hover {
  transform: translate(-4px, -4px);
  box-shadow: 12px 12px 0 rgba(16, 16, 20, .2);
}

/* ---------- 时间线 ---------- */

.page-about .about-tlwrap {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
  align-items: start;
}

@media (min-width: 1180px) {
  .page-about .about-tlwrap {
    grid-template-columns: minmax(0, 1fr) minmax(0, 250px);
    gap: 32px;
  }
}

.page-about .about-tl {
  position: relative;
  margin: 0;
  padding: 0 0 0 30px;
  list-style: none;
  border-left: 3px solid var(--ph-ink);
}

.page-about .about-tl__item {
  position: relative;
  padding-bottom: 28px;
}

.page-about .about-tl__item:last-child {
  padding-bottom: 0;
}

.page-about .about-tl__item::before {
  content: "";
  position: absolute;
  left: -37px;
  top: 5px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--ph-flame-deep);
  border: 3px solid var(--ph-ink);
  box-shadow: 0 0 0 3px var(--ph-cream);
}

.page-about .about-tl__year {
  display: inline-block;
  padding: 2px 9px;
  font-family: var(--ph-font-mono);
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: .12em;
  color: var(--ph-flame-deep);
  border: var(--about-rule) solid var(--ph-flame);
  background: var(--about-mark);
}

.page-about .about-tl__name {
  margin: 10px 0 0;
  font-family: var(--ph-font-display);
  font-weight: 800;
  font-size: 17px;
  letter-spacing: .01em;
  color: var(--ph-ink);
}

.page-about .about-tl__desc {
  margin: 6px 0 0;
  max-width: 36em;
  font-size: 15px;
  line-height: 1.78;
  color: var(--ph-rock);
}

/* ---------- 地域横幅 ---------- */

.page-about .about-banner {
  margin: 28px 0 0;
  border: var(--about-rule) solid var(--ph-ink);
  box-shadow: var(--ph-hard);
  overflow: hidden;
  transition: transform .24s var(--ph-ease), box-shadow .24s var(--ph-ease);
}

.page-about .about-banner img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.page-about .about-banner__cap {
  display: block;
  padding: 11px 16px;
  font-size: 12.5px;
  letter-spacing: .04em;
  color: var(--ph-cream);
  background: var(--ph-night);
}

.page-about .about-banner:hover {
  transform: translate(-4px, -4px);
  box-shadow: 12px 12px 0 rgba(16, 16, 20, .2);
}

.page-about .about-local {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
  border-top: var(--about-rule) solid var(--ph-ink);
}

.page-about .about-local__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 18px;
  align-items: baseline;
  padding: 16px 0;
  border-bottom: var(--about-rule) solid var(--ph-cream-2);
}

.page-about .about-local__num {
  font-family: var(--ph-font-mono);
  font-size: clamp(26px, 3.6vw, 36px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--ph-ice);
  text-shadow: 2px 2px 0 rgba(16, 16, 20, .16);
}

.page-about .about-local__label {
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--ph-rock);
}

/* ---------- 收尾导航 ---------- */

.page-about .about-next {
  padding: clamp(36px, 5vw, 60px) 0 clamp(52px, 7vw, 88px);
  border-top: 3px solid var(--ph-ink);
  margin-top: clamp(28px, 5vw, 56px);
}

.page-about .about-next__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
}

.page-about .about-next__num {
  font-family: var(--ph-font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--ph-flame-deep);
}

.page-about .about-next__title {
  margin: 0;
  font-family: var(--ph-font-display);
  font-weight: 900;
  font-size: clamp(21px, 3vw, 30px);
  letter-spacing: -.01em;
  color: var(--ph-ink);
}

.page-about .about-next__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
  margin-top: 26px;
}

@media (min-width: 820px) {
  .page-about .about-next__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .about-next__card {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 20px 20px 18px;
  border: var(--about-rule) solid var(--ph-ink);
  background: var(--ph-cream);
  box-shadow: var(--ph-hard-sm);
  color: var(--ph-ink);
  text-decoration: none;
  transition: transform .22s var(--ph-ease), box-shadow .22s var(--ph-ease),
              background .22s var(--ph-ease);
}

.page-about .about-next__kicker {
  font-family: var(--ph-font-mono);
  font-size: 11.5px;
  letter-spacing: .14em;
  color: var(--ph-flame-deep);
}

.page-about .about-next__text {
  flex: 1 1 auto;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--ph-rock);
}

.page-about .about-next__go {
  align-self: flex-start;
  padding-bottom: 2px;
  font-family: var(--ph-font-display);
  font-weight: 800;
  font-size: 14px;
  color: var(--ph-ink);
  border-bottom: 3px solid var(--ph-flame);
}

.page-about .about-next__card:hover,
.page-about .about-next__card:focus-visible {
  transform: translate(-4px, -4px);
  box-shadow: 10px 10px 0 rgba(16, 16, 20, .2);
}

.page-about .about-next__card--dark {
  background: var(--ph-night);
  color: var(--ph-cream);
}

.page-about .about-next__card--dark .about-next__text {
  color: rgba(244, 240, 232, .82);
}

.page-about .about-next__card--dark .about-next__kicker {
  color: var(--ph-gold);
}

.page-about .about-next__card--dark .about-next__go {
  color: var(--ph-cream);
  border-bottom-color: var(--ph-ice);
}

/* ---------- 窄屏调优 ---------- */

@media (max-width: 520px) {
  .page-about .about-steps__item {
    padding-left: 0;
    padding-top: 46px;
  }

  .page-about .about-steps__item::before {
    top: 16px;
  }

  .page-about .about-tl {
    padding-left: 24px;
  }

  .page-about .about-tl__item::before {
    left: -31px;
  }

  .page-about .about-local__item {
    grid-template-columns: minmax(0, 1fr);
    gap: 6px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-fig,
  .page-about .about-banner,
  .page-about .about-next__card,
  .page-about .about-rail__node {
    transition: none;
  }

  .page-about .about-fig:hover,
  .page-about .about-banner:hover,
  .page-about .about-next__card:hover,
  .page-about .about-next__card:focus-visible,
  .page-about .about-rail__node:hover,
  .page-about .about-rail__node:focus-visible {
    transform: none;
  }
}
</PAGE_CSS>