.page-about {
  --about-line: rgba(27, 27, 24, .16);
  --about-line-soft: rgba(27, 27, 24, .08);
  --about-ink-soft: rgba(27, 27, 24, .78);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background: var(--deep);
  color: var(--text);
  padding: clamp(96px, 13vh, 150px) 0 clamp(44px, 6vw, 76px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(201, 162, 74, .10) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(201, 162, 74, .10) 1px, transparent 1px);
  background-size: 64px 64px;
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--gold) 0%, rgba(201, 162, 74, .12) 42%, transparent 78%);
}

.page-about .about-hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 54px);
}

.page-about .about-hero .breadcrumbs {
  margin-bottom: 20px;
}

.page-about .about-hero .crumbs-list {
  color: var(--text-dim);
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-size: clamp(2.35rem, 6.2vw, 4.4rem);
  line-height: 1.07;
  letter-spacing: -.02em;
  font-weight: 800;
  color: var(--paper);
}

.page-about .about-hero .lede {
  margin: 24px 0 0;
  max-width: 48ch;
  font-size: clamp(1rem, 1.4vw, 1.08rem);
  line-height: 1.9;
  color: var(--text-dim);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.page-about .about-hero__figure {
  margin: 0;
  aspect-ratio: 3 / 2;
  border: 1px solid var(--line);
  background: var(--panel);
  box-shadow: var(--shadow-island);
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.8) contrast(1.08);
}

.page-about .about-hero__figure .media-caption {
  padding: 10px 12px;
  font-size: .78rem;
  color: var(--text-dim);
  background: rgba(11, 31, 26, .82);
}

/* ---------- 正文底 ---------- */

.page-about .about-body {
  background: var(--paper);
  color: var(--ink);
  padding: clamp(42px, 6vw, 88px) 0 clamp(60px, 8vw, 112px);
}

.page-about .about-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(30px, 4vw, 60px);
}

/* ---------- 侧栏索引 ---------- */

.page-about .about-rail__label {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .22em;
  color: var(--skin-deep);
  text-transform: uppercase;
}

.page-about .about-rail .toc-title {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
}

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

.page-about .about-rail .toc-link {
  display: block;
  padding: 7px 0 7px 13px;
  border-left: 1px solid var(--about-line);
  font-size: .9rem;
  line-height: 1.5;
  color: rgba(27, 27, 24, .68);
  text-decoration: none;
  transition: color var(--fast) ease-out, border-color var(--fast) ease-out, padding-left var(--fast) ease-out;
}

.page-about .about-rail .toc-link:hover,
.page-about .about-rail .toc-link[aria-current="true"] {
  color: var(--ink);
  border-left-color: var(--gold);
  padding-left: 17px;
}

.page-about .about-rail__facts {
  margin-top: 28px;
  padding-top: 20px;
  border-top: 1px dashed var(--about-line);
  display: grid;
  gap: 16px;
}

.page-about .about-rail .stat {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.page-about .about-rail .stat-num {
  font-family: var(--font-mono);
  font-size: clamp(1.35rem, 3vw, 1.7rem);
  font-weight: 700;
  letter-spacing: -.02em;
  line-height: 1;
  color: var(--ink);
}

.page-about .about-rail .stat-label {
  font-size: .78rem;
  line-height: 1.5;
  color: rgba(27, 27, 24, .58);
}

/* ---------- 章节 ---------- */

.page-about .about-main {
  display: grid;
  gap: clamp(52px, 6vw, 92px);
}

.page-about .about-chapter {
  scroll-margin-top: calc(var(--header-h) + 24px);
}

.page-about .about-chapter__num {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: .76rem;
  letter-spacing: .22em;
  color: var(--skin-deep);
}

.page-about .about-chapter__title {
  position: relative;
  margin: 0 0 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--about-line);
  font-size: clamp(1.5rem, 2.7vw, 2.15rem);
  line-height: 1.32;
  font-weight: 700;
  color: var(--ink);
}

.page-about .about-chapter__title::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 64px;
  height: 2px;
  background: var(--gold);
}

.page-about .about-prose {
  max-width: 68ch;
}

.page-about .about-prose--after {
  margin-top: 26px;
}

.page-about .about-prose p {
  margin: 0 0 1.15em;
  font-size: clamp(1rem, 1.15vw, 1.05rem);
  line-height: 1.9;
  color: var(--about-ink-soft);
}

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

.page-about .about-prose a {
  color: var(--skin-deep);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-color: rgba(201, 162, 74, .75);
  transition: color var(--fast) ease-out;
}

.page-about .about-prose a:hover {
  color: var(--ink);
}

/* ---------- 时间线 ---------- */

.page-about .timeline {
  position: relative;
  list-style: none;
  margin: 26px 0 0;
  padding: 0 0 0 30px;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 14px;
  bottom: 14px;
  width: 1px;
  background: linear-gradient(180deg, rgba(201, 162, 74, .85), rgba(201, 162, 74, .14));
}

.page-about .timeline__item {
  position: relative;
  padding-bottom: clamp(30px, 4vw, 48px);
}

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

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -30px;
  top: 9px;
  box-sizing: border-box;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--paper);
  border: 2px solid var(--gold);
}

.page-about .timeline__year {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 3.4vw, 2.25rem);
  font-weight: 700;
  letter-spacing: -.02em;
  line-height: 1;
  color: var(--ink);
}

.page-about .timeline__title {
  margin: 0 0 8px;
  font-size: 1.06rem;
  font-weight: 700;
  color: var(--ink);
}

.page-about .timeline__text {
  margin: 0;
  max-width: 62ch;
  font-size: 1rem;
  line-height: 1.9;
  color: var(--about-ink-soft);
}

.page-about .timeline__split {
  position: relative;
  padding-bottom: clamp(30px, 4vw, 46px);
}

.page-about .timeline__split .media-frame {
  aspect-ratio: 2 / 1;
  border: 1px solid var(--about-line);
  background: var(--mist);
}

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

.page-about .timeline__split .media-caption {
  margin-top: 10px;
  font-size: .78rem;
  letter-spacing: .02em;
  color: rgba(27, 27, 24, .55);
}

/* ---------- 流程 ---------- */

.page-about .flow {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}

.page-about .flow__step {
  position: relative;
  padding: 18px 16px 22px;
  border: 1px solid rgba(201, 162, 74, .45);
  background: rgba(255, 255, 255, .38);
}

.page-about .flow__idx {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .2em;
  color: var(--skin-deep);
}

.page-about .flow__name {
  margin: 0 0 8px;
  font-size: 1.02rem;
  font-weight: 700;
  color: var(--ink);
}

.page-about .flow__desc {
  margin: 0;
  font-size: .92rem;
  line-height: 1.8;
  color: var(--about-ink-soft);
}

.page-about .about-fold {
  margin-top: 28px;
  border: 1px solid var(--about-line);
  border-left: 2px solid var(--gold);
  background: rgba(255, 255, 255, .34);
}

.page-about .about-fold .fold-body {
  padding: 4px 18px 18px;
}

.page-about .about-fold .fold-body p {
  margin: 0 0 1em;
  font-size: .95rem;
  line-height: 1.9;
  color: var(--about-ink-soft);
}

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

/* ---------- 服务对象 ---------- */

.page-about .serve-grid {
  margin-top: 26px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about .serve-card {
  padding: 20px 20px 22px;
  border: 1px solid var(--about-line);
  border-top: 2px solid var(--gold);
  background: rgba(255, 255, 255, .42);
}

.page-about .serve-card__name {
  margin: 0 0 10px;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--ink);
}

.page-about .serve-card__text {
  margin: 0;
  font-size: .96rem;
  line-height: 1.85;
  color: var(--about-ink-soft);
}

/* ---------- 本地合作 ---------- */

.page-about .local-block {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(20px, 3vw, 36px);
  align-items: center;
}

.page-about .local-block .media-frame {
  aspect-ratio: 4 / 3;
  border: 1px solid var(--about-line);
  background: var(--mist);
}

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

.page-about .local-block .media-caption {
  margin-top: 10px;
  font-size: .78rem;
  color: rgba(27, 27, 24, .55);
}

/* ---------- 团队构成 ---------- */

.page-about .team-stack {
  display: flex;
  gap: 4px;
  margin: 26px 0 30px;
  padding: 0;
}

.page-about .stack-seg {
  position: relative;
  flex: var(--w) 1 0;
  min-width: 0;
  outline-offset: 4px;
}

.page-about .stack-seg__bar {
  display: block;
  height: 58px;
  border: 1px solid rgba(201, 162, 74, .55);
  background: linear-gradient(180deg, rgba(201, 162, 74, .30), rgba(201, 162, 74, .10));
  transition: background var(--mid) ease-out;
}

.page-about .stack-seg:hover .stack-seg__bar,
.page-about .stack-seg:focus .stack-seg__bar {
  background: linear-gradient(180deg, rgba(201, 162, 74, .52), rgba(201, 162, 74, .20));
}

.page-about .stack-seg__num {
  display: block;
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: clamp(.92rem, 1.9vw, 1.05rem);
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--ink);
}

.page-about .stack-seg__name {
  display: block;
  margin-top: 2px;
  font-size: .8rem;
  line-height: 1.5;
  color: rgba(27, 27, 24, .62);
}

.page-about .stack-tip {
  position: absolute;
  left: 0;
  bottom: calc(100% + 10px);
  z-index: 4;
  width: max-content;
  max-width: 240px;
  padding: 11px 13px;
  border: 1px solid var(--line);
  background: var(--deep);
  color: var(--text);
  font-size: .8rem;
  line-height: 1.7;
  opacity: 0;
  visibility: hidden;
  transform: translateY(6px);
  transition: opacity var(--fast) ease-out, transform var(--fast) ease-out, visibility var(--fast);
  pointer-events: none;
}

.page-about .stack-seg:last-child .stack-tip {
  left: auto;
  right: 0;
}

.page-about .stack-seg:hover .stack-tip,
.page-about .stack-seg:focus .stack-tip {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

/* ---------- 断点 ---------- */

@media (min-width: 700px) {
  .page-about .serve-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

@media (min-width: 780px) {
  .page-about .flow {
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 8px;
  }

  .page-about .flow__step::after {
    content: "";
    position: absolute;
    right: -7px;
    top: 50%;
    width: 6px;
    height: 6px;
    border-top: 1px solid var(--gold);
    border-right: 1px solid var(--gold);
    transform: translateY(-50%) rotate(45deg);
  }

  .page-about .flow__step:last-child::after {
    display: none;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: end;
  }

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

  .page-about .local-block {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  }
}

@media (min-width: 1024px) {
  .page-about .about-layout {
    grid-template-columns: minmax(200px, 3fr) minmax(0, 9fr);
    align-items: start;
    gap: clamp(36px, 4.5vw, 72px);
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 20px);
  }
}

@media (max-width: 680px) {
  .page-about .team-stack {
    overflow-x: auto;
    padding-bottom: 8px;
  }

  .page-about .stack-seg {
    min-width: 128px;
    flex-grow: 1;
  }

  .page-about .stack-tip {
    max-width: 200px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail .toc-link,
  .page-about .stack-seg__bar,
  .page-about .stack-tip {
    transition: none;
  }
}

.page-about {
  --w: inherit;
}