.page-about {
  --about-index-w: 236px;
  background: var(--night);
  color: var(--mist);
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  padding-block: clamp(20px, 3vw, 30px) 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-block: clamp(24px, 4vw, 44px) clamp(56px, 8vw, 104px);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(32px, 5vw, 56px);
  align-items: center;
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-size: clamp(30px, 5.4vw, 54px);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.16;
  color: var(--mist);
}

.page-about .about-hero__lede {
  margin: clamp(16px, 2vw, 22px) 0 0;
  max-width: 38em;
  color: var(--stone);
  font-size: 17px;
  line-height: 1.78;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(22px, 3vw, 32px);
}

.page-about .about-hero__meta {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 18px 24px;
  margin: clamp(28px, 4vw, 40px) 0 0;
  padding-top: clamp(20px, 3vw, 28px);
  border-top: 1px solid var(--line);
}

.page-about .about-hero__meta dt {
  margin: 0 0 6px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--stone);
}

.page-about .about-hero__meta dd {
  margin: 0;
  font-size: 16px;
  font-weight: 800;
  color: var(--gold);
}

.page-about .about-hero__figure {
  margin: 0;
  background: var(--trench);
  border: 1px solid var(--line);
  clip-path: polygon(0 0, calc(100% - 30px) 0, 100% 30px, 100% 100%, 0 100%);
  overflow: hidden;
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
}

.page-about .about-hero__cap {
  padding: 12px 16px;
  border-top: 1px solid var(--line);
  font-family: var(--mono);
  font-size: 12px;
  line-height: 1.6;
  color: var(--stone);
}

/* ---------- 主体双轨 ---------- */
.page-about .about-body {
  padding-block: clamp(56px, 8vw, 104px);
}

.page-about .about-body__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(30px, 4vw, 52px);
}

.page-about .about-index {
  border-top: 1px solid var(--line);
  padding-top: 16px;
}

.page-about .about-index__label {
  margin: 0;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--gold);
}

.page-about .about-index__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 14px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-index__link {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 7px 12px;
  font-size: 14px;
  color: var(--stone);
  text-decoration: none;
  border: 1px solid var(--line-soft);
  clip-path: polygon(0 0, calc(100% - 9px) 0, 100% 9px, 100% 100%, 0 100%);
  transition: color 180ms var(--ease), border-color 180ms var(--ease), background 180ms var(--ease);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--neon);
  border-color: var(--neon);
  background: rgba(63, 211, 190, 0.08);
}

.page-about .about-index__no {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--gold);
}

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  scroll-margin-top: 96px;
}

.page-about .about-chapter + .about-chapter {
  margin-top: clamp(44px, 6vw, 76px);
  padding-top: clamp(44px, 6vw, 76px);
  border-top: 1px solid var(--line-soft);
}

.page-about .about-chapter__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0 16px;
  align-items: start;
  margin-bottom: clamp(18px, 2.5vw, 26px);
}

.page-about .about-chapter__mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  margin-top: 4px;
  clip-path: polygon(50% 0, 100% 25%, 100% 75%, 50% 100%, 0 75%, 0 25%);
  background: var(--deep-red);
  color: var(--mist);
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 700;
}

.page-about .about-chapter__title {
  margin: 0;
  font-size: clamp(22px, 3vw, 34px);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.25;
  color: var(--mist);
}

.page-about .about-chapter__prose {
  max-width: 40em;
}

.page-about .about-chapter__prose p {
  margin: 0;
  color: var(--stone);
  font-size: 17px;
  line-height: 1.82;
}

.page-about .about-chapter__prose p + p {
  margin-top: 16px;
}

.page-about .about-chapter__lead {
  max-width: 38em;
  margin: 0 0 clamp(24px, 3vw, 34px);
  color: var(--stone);
  font-size: 17px;
  line-height: 1.82;
}

.page-about .about-chapter__lead a,
.page-about .about-chapter__foot a {
  color: var(--neon);
  text-decoration: none;
  border-bottom: 1px solid rgba(63, 211, 190, 0.4);
}

.page-about .about-chapter__lead a:hover,
.page-about .about-chapter__foot a:hover {
  border-bottom-color: var(--neon);
}

.page-about .about-chapter__foot {
  max-width: 40em;
  margin: clamp(22px, 3vw, 30px) 0 0;
  color: var(--stone);
  font-size: 15px;
  line-height: 1.82;
}

.page-about .about-chapter__figure {
  margin: clamp(22px, 3vw, 30px) 0;
  border: 1px solid var(--line-soft);
  background: var(--night);
  clip-path: polygon(0 0, calc(100% - 22px) 0, 100% 22px, 100% 100%, 0 100%);
  overflow: hidden;
}

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

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  margin-top: clamp(8px, 1.5vw, 14px);
}

.page-about .about-timeline__list {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(252px, 1fr);
  gap: 0 clamp(14px, 2.4vw, 30px);
  margin: 0;
  padding: 0 0 10px;
  list-style: none;
  overflow-x: auto;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-timeline__node {
  position: relative;
  padding: 46px 14px 0 0;
  scroll-snap-align: start;
}

.page-about .about-timeline__node::before {
  content: "";
  position: absolute;
  top: 15px;
  left: 26px;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--gold), rgba(200, 162, 76, 0.14));
}

.page-about .about-timeline__node:last-child::before {
  display: none;
}

.page-about .about-timeline__dot {
  position: absolute;
  top: 9px;
  left: 6px;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  border: 2px solid var(--gold);
  background: var(--trench);
  transition: background 180ms var(--ease), box-shadow 180ms var(--ease), border-color 180ms var(--ease);
}

.page-about .about-timeline__node:hover .about-timeline__dot {
  background: var(--neon);
  border-color: var(--neon);
  box-shadow: 0 0 0 5px rgba(63, 211, 190, 0.16);
}

.page-about .about-timeline__ver {
  margin: 0 0 6px;
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--gold);
}

.page-about .about-timeline__name {
  margin: 0 0 10px;
  font-size: 20px;
  font-weight: 900;
  letter-spacing: -0.01em;
  color: var(--mist);
}

.page-about .about-timeline__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--stone);
}

.page-about .about-timeline__extra {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px dashed var(--line-soft);
}

.page-about .about-timeline__extra .mono {
  margin: 0;
  font-size: 12px;
  line-height: 1.7;
  color: var(--teal);
  word-break: break-word;
}

/* ---------- 新旧栏目映射 ---------- */
.page-about .about-map {
  margin-top: clamp(20px, 3vw, 30px);
}

.page-about .about-map__head,
.page-about .about-map__row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.3fr) minmax(0, 1fr);
  gap: 6px 18px;
  align-items: baseline;
}

.page-about .about-map__head {
  padding: 0 0 10px;
  border-bottom: 1px solid var(--line);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--stone);
}

.page-about .about-map__row {
  padding: 13px 0;
  border-bottom: 1px solid var(--line-soft);
  transition: background 160ms var(--ease), padding-left 160ms var(--ease);
}

.page-about .about-map__row:hover {
  background: rgba(31, 111, 107, 0.16);
  padding-left: 10px;
}

.page-about .about-map__old {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 15px;
  font-weight: 700;
  color: var(--mist);
  word-break: break-word;
}

.page-about .about-map__old::before {
  content: "";
  flex: 0 0 auto;
  width: 8px;
  height: 8px;
  background: var(--teal);
  clip-path: polygon(50% 0, 100% 50%, 50% 100%, 0 50%);
}

.page-about .about-map__to a {
  color: var(--neon);
  font-size: 15px;
  text-decoration: none;
  border-bottom: 1px solid rgba(63, 211, 190, 0.32);
  transition: border-color 160ms var(--ease), color 160ms var(--ease);
}

.page-about .about-map__to a:hover {
  border-bottom-color: var(--neon);
}

.page-about .about-map__path {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--gold);
  word-break: break-all;
}

/* ---------- 团队分工 ---------- */
.page-about .about-roles {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: clamp(22px, 3vw, 30px);
}

.page-about .about-role {
  padding: 22px 24px 24px;
  background: var(--trench);
  clip-path: polygon(0 0, calc(100% - 16px) 0, 100% 16px, 100% 100%, 0 100%);
  transition: background 200ms var(--ease);
}

.page-about .about-role:hover {
  background: #17304A;
}

.page-about .about-role__badge {
  display: grid;
  place-items: center;
  width: 30px;
  height: 34px;
  clip-path: polygon(50% 0, 100% 25%, 100% 75%, 50% 100%, 0 75%, 0 25%);
  background: var(--deep-red);
  color: var(--mist);
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 700;
}

.page-about .about-role__name {
  margin: 14px 0 8px;
  font-size: 17px;
  font-weight: 800;
  color: var(--mist);
}

.page-about .about-role__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--stone);
}

.page-about .about-chapter__figure--team {
  margin-top: clamp(26px, 3.5vw, 38px);
}

/* ---------- 数据条 ---------- */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: 0;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}

.page-about .about-stat {
  padding: clamp(18px, 2.6vw, 26px) clamp(14px, 2vw, 20px);
  background: var(--night);
}

.page-about .about-stat__num {
  display: block;
  font-size: clamp(26px, 3.4vw, 38px);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.1;
  color: var(--gold);
}

.page-about .about-stat__label {
  display: block;
  margin-top: 8px;
  font-size: 14px;
  line-height: 1.6;
  color: var(--stone);
}

/* ---------- 服务范围（暖色区） ---------- */
.page-about .about-region {
  color: var(--ink);
}

.page-about .about-region__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0 16px;
  align-items: start;
  margin-bottom: clamp(24px, 3.5vw, 36px);
}

.page-about .about-region .about-chapter__mark {
  background: var(--teal);
}

.page-about .about-region .about-chapter__title {
  color: var(--ink);
}

.page-about .about-region__lead {
  max-width: 40em;
  margin: 12px 0 0;
  font-size: 17px;
  line-height: 1.8;
  color: #4A5A68;
}

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

.page-about .about-region__card {
  padding: 22px 24px;
  background: #FFFFFF;
  clip-path: polygon(0 0, calc(100% - 16px) 0, 100% 16px, 100% 100%, 0 100%);
}

.page-about .about-region__label {
  margin: 0 0 10px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--deep-red);
}

.page-about .about-region__card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.82;
  color: #3D4B57;
}

.page-about .about-region__contacts {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-region__contacts li {
  font-size: 15px;
  line-height: 1.82;
  color: #3D4B57;
  word-break: break-word;
}

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

.page-about .about-region__foot {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px 20px;
  margin: clamp(26px, 3.5vw, 36px) 0 0;
  padding-top: clamp(20px, 3vw, 28px);
  border-top: 1px solid rgba(34, 48, 60, 0.16);
  font-size: 15px;
  line-height: 1.82;
  color: #3D4B57;
}

.page-about .about-region__foot > a.btn {
  flex: 0 0 auto;
}

/* ---------- 断点 ---------- */
@media (min-width: 620px) {
  .page-about .about-roles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 760px) {
  .page-about .about-region__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

@media (min-width: 860px) {
  .page-about .about-timeline__list {
    grid-auto-columns: minmax(0, 1fr);
    overflow-x: visible;
    padding-bottom: 0;
  }
}

@media (hover: hover) and (min-width: 860px) {
  .page-about .about-timeline__extra {
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    padding-top: 0;
    margin-top: 0;
    border-top-color: transparent;
    transition: max-height 240ms var(--ease), opacity 240ms var(--ease),
                padding-top 240ms var(--ease), margin-top 240ms var(--ease),
                border-color 240ms var(--ease);
  }

  .page-about .about-timeline__node:hover .about-timeline__extra,
  .page-about .about-timeline__node:focus-within .about-timeline__extra {
    max-height: 180px;
    opacity: 1;
    padding-top: 12px;
    margin-top: 12px;
    border-top-color: var(--line-soft);
  }
}

@media (min-width: 940px) {
  .page-about .about-hero__grid {
    grid-template-columns: 7fr 5fr;
    gap: clamp(40px, 5vw, 72px);
  }
}

@media (min-width: 1000px) {
  .page-about .about-roles {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 1024px) {
  .page-about .about-body__grid {
    grid-template-columns: var(--about-index-w) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-index {
    position: sticky;
    top: 92px;
    border-top: 0;
    border-left: 1px solid var(--line);
    padding: 0 0 0 20px;
  }

  .page-about .about-index__list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 0;
    margin-top: 14px;
  }

  .page-about .about-index__link {
    display: flex;
    padding: 10px 0;
    border: 0;
    border-bottom: 1px solid var(--line-soft);
    clip-path: none;
    background: none;
  }

  .page-about .about-index__link:hover,
  .page-about .about-index__link:focus-visible {
    color: var(--neon);
    background: none;
    padding-left: 6px;
  }
}

@media (min-width: 1100px) {
  .page-about .about-map__head,
  .page-about .about-map__row {
    gap: 6px 24px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}