.page-about {
  --about-pad: clamp(56px, 8vw, 120px);
  --about-gap: clamp(28px, 4.5vw, 64px);
  --about-line-gap: clamp(20px, 3vw, 44px);
  position: relative;
  isolation: isolate;
  overflow-x: clip;
  background: var(--ink-900);
  color: var(--text);
  font-family: var(--font-sans);
  padding-bottom: clamp(56px, 8vw, 112px);
}

.page-about::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, var(--line-soft) 1px, transparent 1px),
    linear-gradient(to bottom, var(--line-soft) 1px, transparent 1px);
  background-size: 96px 96px;
  opacity: 0.22;
}

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

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  padding-top: clamp(20px, 3vw, 36px);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-crumb a {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-crumb a:hover,
.page-about .about-crumb a:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

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

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: var(--about-gap);
  padding-top: clamp(24px, 4vw, 48px);
}

.page-about .about-hero__copy .eyebrow {
  margin: 0 0 18px;
}

.page-about .about-hero h1 {
  margin: 0;
  font-size: clamp(38px, 8.4vw, 88px);
  line-height: 1.02;
  letter-spacing: -0.04em;
  font-weight: 900;
  text-wrap: balance;
}

.page-about .about-hero__lead {
  margin: clamp(20px, 3vw, 30px) 0 0;
  max-width: 34em;
  color: var(--text);
  font-size: clamp(16px, 2vw, 19px);
  line-height: 1.75;
}

.page-about .about-hero__body {
  margin: 16px 0 0;
  max-width: 34em;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.8;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(24px, 4vw, 38px);
}

.page-about .about-hero__visual {
  position: relative;
  margin: 0;
  border: 1px solid var(--line);
  background: var(--ink-800);
}

.page-about .about-hero__visual::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 2;
  pointer-events: none;
  background:
    radial-gradient(circle at 70% 22%, rgba(54, 224, 232, 0.16), transparent 58%),
    linear-gradient(to top, rgba(5, 7, 13, 0.86), transparent 46%);
}

.page-about .about-hero__visual::after {
  content: "";
  position: absolute;
  top: 14px;
  left: 14px;
  width: 18px;
  height: 18px;
  z-index: 3;
  pointer-events: none;
  background:
    linear-gradient(var(--cyan), var(--cyan)) center / 1px 100% no-repeat,
    linear-gradient(var(--cyan), var(--cyan)) center / 100% 1px no-repeat;
  opacity: 0.85;
}

.page-about .about-hero__visual img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 1 / 1;
  object-fit: cover;
}

.page-about .about-figcap {
  position: relative;
  z-index: 3;
  display: block;
  padding: 12px 14px;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  border-top: 1px solid var(--line);
  background: var(--ink-800);
}

/* ---------- 数据条 ---------- */
.page-about .about-stats {
  margin-top: clamp(40px, 6vw, 76px);
}

.page-about .about-stats__list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0;
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 20px 12px 22px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-stat__num {
  font-family: var(--font-mono);
  font-size: clamp(30px, 5.4vw, 48px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--cyan);
}

.page-about .about-stat__unit {
  font-size: 0.55em;
  margin-left: 2px;
  color: var(--text);
}

.page-about .about-stat__suffix {
  font-size: 13px;
  color: var(--text);
}

.page-about .about-stat__label {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--muted);
}

/* ---------- 章节索引 ---------- */
.page-about .about-index {
  margin-top: clamp(28px, 4vw, 46px);
}

.page-about .about-index__list {
  display: flex;
  gap: 10px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
  -webkit-overflow-scrolling: touch;
}

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

.page-about .about-index__list a {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 9px 16px;
  font-size: 13px;
  color: var(--muted);
  text-decoration: none;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background: var(--panel);
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease), transform 0.2s var(--ease);
}

.page-about .about-index__list a .t-mono {
  font-size: 11px;
  color: var(--cobalt);
}

.page-about .about-index__list a:hover,
.page-about .about-index__list a:focus-visible {
  color: var(--text);
  border-color: var(--cyan);
  transform: translateY(-2px);
}

/* ---------- 通用小节 ---------- */
.page-about .section {
  padding-block: var(--about-pad);
  scroll-margin-top: 96px;
}

.page-about .about-link {
  display: inline-block;
  margin-top: clamp(18px, 2.5vw, 26px);
  padding-bottom: 3px;
  font-size: 14px;
  letter-spacing: 0.02em;
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(54, 224, 232, 0.45);
  transition: border-color 0.2s var(--ease), color 0.2s var(--ease);
}

.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  color: var(--text);
  border-bottom-color: var(--text);
}

.page-about h2 {
  margin: 0;
  font-size: clamp(26px, 4vw, 44px);
  line-height: 1.14;
  letter-spacing: -0.035em;
  font-weight: 900;
  text-wrap: balance;
}

.page-about h3 {
  margin: 0;
  font-size: 17px;
  letter-spacing: -0.01em;
  font-weight: 700;
}

.page-about p {
  margin: 0;
}

.page-about .about-split p,
.page-about .about-docs p,
.page-about .about-change p,
.page-about .about-history p,
.page-about .about-team p,
.page-about .about-place p {
  color: var(--muted);
  line-height: 1.8;
}

.page-about .about-link:focus-visible,
.page-about .about-index__list a:focus-visible,
.page-about .btn:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

/* ---------- 栏目协同 ---------- */
.page-about .about-split {
  background: linear-gradient(180deg, var(--ink-800) 0%, rgba(10, 16, 32, 0) 100%);
}

.page-about .about-split__inner {
  display: grid;
  gap: var(--about-gap);
}

.page-about .about-split__aside h2 {
  margin: 10px 0 20px;
}

.page-about .about-split__aside p + p {
  margin-top: 14px;
}

.page-about .about-figure {
  margin: 0 0 clamp(24px, 3.5vw, 36px);
  border: 1px solid var(--line);
  background: var(--panel);
}

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

.page-about .about-lanes {
  display: grid;
  gap: clamp(18px, 3vw, 32px);
}

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

.page-about .about-lane h3 {
  color: var(--text);
}

.page-about .about-steps {
  display: grid;
  gap: 10px;
  margin: 16px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-steps li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 9px 0;
  font-size: 15px;
  color: var(--text);
  border-bottom: 1px dashed var(--line-soft);
}

.page-about .about-steps .t-mono {
  flex: 0 0 auto;
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--cobalt);
}

.page-about .about-lane:first-child .about-steps .t-mono {
  color: var(--cyan);
}

/* ---------- 帮助文档 ---------- */
.page-about .about-docs__grid {
  display: grid;
  gap: var(--about-gap);
}

.page-about .about-docs__head h2 {
  margin: 10px 0 20px;
}

.page-about .about-docs__panel {
  padding: clamp(20px, 3vw, 34px);
  border: 1px solid var(--line);
  background: var(--ink-800);
}

.page-about .about-docs__label {
  margin: 0 0 16px;
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-taglist {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 clamp(20px, 3vw, 30px);
  padding: 0;
  list-style: none;
}

.page-about .about-taglist .tag {
  display: inline-block;
  padding: 7px 12px;
  font-size: 13px;
}

.page-about .about-docnotes {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-docnotes li {
  display: grid;
  gap: 4px;
  padding-top: 12px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
  border-top: 1px solid var(--line);
}

.page-about .about-docnotes .t-mono {
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--cyan);
}

/* ---------- 四月版本 ---------- */
.page-about .about-change {
  background: linear-gradient(180deg, rgba(36, 91, 255, 0.1) 0%, rgba(5, 7, 13, 0) 78%);
}

.page-about .about-change__inner {
  display: grid;
  gap: var(--about-gap);
}

.page-about .about-change__head h2 {
  margin: 10px 0 20px;
}

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

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

.page-about .about-detail summary {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 18px 0;
  cursor: pointer;
  list-style: none;
  font-size: 16px;
  font-weight: 700;
  color: var(--text);
  transition: color 0.2s var(--ease);
}

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

.page-about .about-detail summary:hover,
.page-about .about-detail summary:focus-visible {
  color: var(--cyan);
  outline: none;
}

.page-about .about-detail__no {
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--cobalt);
}

.page-about .about-detail__mark {
  position: relative;
  width: 14px;
  height: 14px;
  margin-left: auto;
  flex: 0 0 auto;
}

.page-about .about-detail__mark::before,
.page-about .about-detail__mark::after {
  content: "";
  position: absolute;
  background: var(--cyan);
  transition: transform 0.2s var(--ease), opacity 0.2s var(--ease);
}

.page-about .about-detail__mark::before {
  top: 6px;
  left: 0;
  width: 14px;
  height: 1px;
}

.page-about .about-detail__mark::after {
  top: 0;
  left: 6px;
  width: 1px;
  height: 14px;
}

.page-about .about-detail[open] .about-detail__mark::after {
  transform: scaleY(0);
  opacity: 0;
}

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

.page-about .about-detail__body p {
  max-width: 46em;
  font-size: 15px;
}

/* ---------- 发展历程 ---------- */
.page-about .about-history__inner {
  display: grid;
  gap: var(--about-gap);
}

.page-about .about-history__head h2 {
  margin: 10px 0 20px;
}

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

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  top: 8px;
  bottom: 8px;
  left: 5px;
  width: 1px;
  background: linear-gradient(to bottom, var(--cyan), var(--cobalt) 55%, rgba(27, 42, 68, 0.2));
}

.page-about .about-timeline__item {
  position: relative;
  padding-bottom: clamp(22px, 3vw, 34px);
}

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

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  top: 7px;
  left: -30px;
  width: 11px;
  height: 11px;
  border: 1px solid var(--cyan);
  background: var(--ink-900);
}

.page-about .about-timeline__item::after {
  content: "";
  position: absolute;
  top: 11px;
  left: -26px;
  width: 3px;
  height: 3px;
  background: var(--cyan);
}

.page-about .about-timeline__year {
  display: block;
  margin-bottom: 6px;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--cobalt);
}

.page-about .about-timeline__item h3 {
  margin-bottom: 6px;
  color: var(--text);
}

.page-about .about-timeline__item p {
  font-size: 15px;
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  background: var(--ink-800);
}

.page-about .about-team__head h2 {
  margin: 10px 0 20px;
}

.page-about .about-team__inner > .about-team__head {
  max-width: 46em;
}

.page-about .about-metrics {
  display: grid;
  gap: 0;
  margin: clamp(28px, 4vw, 44px) 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.page-about .about-metric {
  padding: 22px 0;
  border-bottom: 1px solid var(--line);
  transition: transform 0.25s var(--ease);
}

.page-about .about-metric__num {
  display: block;
  font-size: clamp(28px, 4.6vw, 40px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--text);
  transition: color 0.25s var(--ease);
}

.page-about .about-metric h3 {
  margin: 10px 0 6px;
  font-size: 15px;
  color: var(--text);
}

.page-about .about-metric p {
  font-size: 14px;
  max-width: 30em;
}

.page-about .about-metric:hover {
  transform: translateY(-3px);
}

.page-about .about-metric:hover .about-metric__num {
  color: var(--cyan);
}

.page-about .about-team__note {
  max-width: 52em;
  margin-top: clamp(24px, 3vw, 36px);
  padding-top: 18px;
  font-size: 15px;
  border-top: 1px solid var(--line);
}

.page-about .about-team__note a,
.page-about .about-place__copy a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(54, 224, 232, 0.45);
}

.page-about .about-team__note a:hover,
.page-about .about-place__copy a:hover,
.page-about .about-team__note a:focus-visible,
.page-about .about-place__copy a:focus-visible {
  color: var(--text);
  border-bottom-color: var(--text);
}

/* ---------- 重庆落点 ---------- */
.page-about .about-place__inner {
  display: grid;
  gap: var(--about-gap);
}

.page-about .about-place__copy h2 {
  margin: 10px 0 20px;
}

.page-about .about-place__contact {
  display: grid;
  gap: 14px;
  margin: clamp(20px, 3vw, 30px) 0;
  padding: 0;
}

.page-about .about-place__contact > div {
  padding-top: 12px;
  border-top: 1px solid var(--line);
}

.page-about .about-place__contact dt {
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-place__contact dd {
  margin: 6px 0 0;
  font-family: var(--font-mono);
  font-size: 15px;
  letter-spacing: 0.01em;
  color: var(--text);
  overflow-wrap: anywhere;
}

.page-about .about-place__figure {
  position: relative;
  margin: 0;
  border: 1px solid var(--line);
  background: var(--panel);
}

.page-about .about-place__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 2 / 1;
  object-fit: cover;
}

.page-about .about-place__figure::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background: radial-gradient(circle at 28% 68%, rgba(36, 91, 255, 0.24), transparent 62%);
}

/* ---------- 结尾行动区 ---------- */
.page-about .about-cta {
  margin-top: clamp(8px, 2vw, 24px);
  padding: clamp(28px, 4vw, 52px);
  border: 1px solid var(--line);
  border-left: 3px solid var(--orange);
  background: linear-gradient(120deg, var(--panel) 0%, var(--ink-800) 100%);
}

.page-about .about-cta h2 {
  font-size: clamp(24px, 3.4vw, 38px);
  max-width: 24em;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(20px, 3vw, 30px);
}

/* ---------- 平板及以上 ---------- */
@media (min-width: 720px) {
  .page-about .about-stats__list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-stat {
    padding-left: 18px;
    border-left: 1px solid var(--line);
  }

  .page-about .about-stat:first-child {
    padding-left: 0;
    border-left: 0;
  }

  .page-about .about-lanes {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: clamp(20px, 3vw, 40px);
  }

  .page-about .about-metrics {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: clamp(24px, 4vw, 48px);
  }

  .page-about .about-place__contact {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    column-gap: 20px;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 960px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.06fr) minmax(0, 0.94fr);
    align-items: end;
    gap: clamp(40px, 6vw, 84px);
  }

  .page-about .about-hero__visual {
    margin-bottom: 6px;
  }

  .page-about .about-split__inner {
    grid-template-columns: minmax(0, 0.78fr) minmax(0, 1.22fr);
    gap: clamp(36px, 5vw, 80px);
    align-items: start;
  }

  .page-about .about-split__aside {
    position: sticky;
    top: 108px;
    padding-top: 8px;
  }

  .page-about .about-docs__grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: clamp(40px, 6vw, 88px);
    align-items: start;
  }

  .page-about .about-change__inner {
    grid-template-columns: minmax(0, 0.86fr) minmax(0, 1.14fr);
    gap: clamp(36px, 5vw, 76px);
    align-items: start;
  }

  .page-about .about-history__inner {
    grid-template-columns: minmax(0, 0.7fr) minmax(0, 1.3fr);
    gap: clamp(36px, 5vw, 80px);
    align-items: start;
  }

  .page-about .about-place__inner {
    grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.05fr);
    gap: clamp(36px, 5vw, 72px);
    align-items: center;
  }

  .page-about .about-team__inner {
    display: grid;
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .about-metrics {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    column-gap: clamp(20px, 3vw, 40px);
  }

  .page-about .about-place__figure {
    order: 2;
  }
}

@media (min-width: 1200px) {
  .page-about .about-hero h1 {
    max-width: 15ch;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__list a,
  .page-about .about-metric,
  .page-about .about-metric__num,
  .page-about .about-crumb a,
  .page-about .about-link {
    transition: none;
  }

  .page-about .about-index__list a:hover,
  .page-about .about-metric:hover {
    transform: none;
  }
}