.page-about {
  background: var(--yx-paper);
  color: var(--yx-ink);
  font-family: var(--yx-sans);
  line-height: 1.7;
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  padding-top: clamp(16px, 3vw, 28px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-top: clamp(24px, 4vw, 48px);
  border-top: 0;
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(28px, 4vw, 56px);
}

.page-about .about-hero__lead .yx-title--xl {
  font-family: var(--yx-serif);
  letter-spacing: -0.01em;
  line-height: 1.14;
  margin: 0.2em 0 0.5em;
}

.page-about .about-hero__lead .yx-lede {
  max-width: 62ch;
  color: var(--yx-ink);
  margin: 0;
}

.page-about .about-hero__note {
  margin: clamp(16px, 2.4vw, 24px) 0 0;
  padding-left: 14px;
  border-left: 3px solid var(--yx-orange);
  font-size: 0.94rem;
  color: var(--yx-muted);
  max-width: 60ch;
}

.page-about .about-facts {
  border-top: 1px solid var(--yx-line);
  align-self: end;
}

.page-about .about-facts__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 0;
  border-bottom: 1px solid var(--yx-line);
}

.page-about .about-facts__key {
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  color: var(--yx-muted);
}

.page-about .about-facts__val {
  font-family: var(--yx-mono);
  font-weight: 500;
  font-size: clamp(1.5rem, 3.4vw, 2.05rem);
  color: var(--yx-blue);
  line-height: 1.1;
}

.page-about .about-facts__val small {
  font-family: var(--yx-sans);
  font-size: 0.5em;
  font-weight: 500;
  color: var(--yx-muted);
  margin-left: 4px;
}

/* ---------- 起点 ---------- */
.page-about .about-origin .yx-title {
  font-family: var(--yx-serif);
  margin: 0.15em 0 0.6em;
}

.page-about .about-origin__text {
  margin: 0 0 1em;
  max-width: 68ch;
}

.page-about .about-origin__list {
  list-style: none;
  margin: clamp(20px, 3vw, 32px) 0 0;
  padding: 0;
  border-top: 1px solid var(--yx-line);
}

.page-about .about-origin__list li {
  display: grid;
  grid-template-columns: 42px 1fr;
  gap: 10px;
  align-items: baseline;
  padding: 12px 0;
  border-bottom: 1px solid var(--yx-line);
  font-size: 0.95rem;
}

.page-about .about-origin__list .yx-mono {
  color: var(--yx-blue);
  font-size: 0.82rem;
  letter-spacing: 0.06em;
}

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

/* ---------- 时间轴 ---------- */
.page-about .about-tl {
  list-style: none;
  margin: clamp(28px, 4vw, 48px) 0 0;
  padding: 0;
  position: relative;
}

.page-about .about-tl::before {
  content: "";
  position: absolute;
  top: 6px;
  bottom: 6px;
  left: 7px;
  width: 1px;
  background: var(--yx-line);
}

.page-about .about-tl__item {
  position: relative;
  padding-left: 40px;
  padding-bottom: clamp(20px, 3vw, 32px);
}

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

.page-about .about-tl__marker {
  position: absolute;
  left: 0;
  top: 9px;
  width: 15px;
  height: 15px;
  background: var(--yx-blue);
  border: 3px solid var(--yx-pale);
  box-sizing: content-box;
}

.page-about .about-tl__card {
  background: var(--yx-paper);
  border: 1px solid var(--yx-line);
  padding: clamp(14px, 2vw, 20px) clamp(16px, 2.2vw, 24px);
  transition: border-color 180ms var(--yx-ease);
}

.page-about .about-tl__item:hover .about-tl__card {
  border-color: var(--yx-blue);
}

.page-about .about-tl__trigger {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 6px 18px;
  align-items: baseline;
  width: 100%;
  padding: 0;
  border: 0;
  background: none;
  text-align: left;
  color: inherit;
  font: inherit;
  cursor: pointer;
}

.page-about .about-tl__trigger:focus-visible {
  outline: 2px solid var(--yx-orange);
  outline-offset: 3px;
}

.page-about .about-tl__year {
  font-size: clamp(1.25rem, 2.6vw, 1.7rem);
  font-weight: 500;
  color: var(--yx-blue-deep);
  letter-spacing: -0.01em;
  line-height: 1.2;
}

.page-about .about-tl__title {
  font-family: var(--yx-serif);
  font-weight: 600;
  font-size: clamp(1rem, 1.6vw, 1.12rem);
  color: var(--yx-ink);
}

.page-about .about-tl__body {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--yx-line);
}

.page-about .about-tl__body p {
  margin: 0;
  font-size: 0.95rem;
  color: var(--yx-ink);
  max-width: 64ch;
}

/* ---------- 上海六区宽幅带 ---------- */
.page-about .about-eyebrow--light {
  color: var(--yx-orange);
}

.page-about .about-title--light {
  font-family: var(--yx-serif);
  color: #fff;
}

.page-about .about-lede--light {
  color: #C9DBEB;
  max-width: 64ch;
}

.page-about .about-band {
  margin-top: clamp(28px, 4vw, 44px);
  border: 1px solid rgba(201, 219, 235, 0.35);
}

.page-about .about-band__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
}

.page-about .about-band__cell {
  padding: clamp(14px, 2vw, 20px) clamp(12px, 2vw, 18px);
  border-right: 1px solid rgba(201, 219, 235, 0.35);
  border-bottom: 1px solid rgba(201, 219, 235, 0.35);
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .about-band__cell:nth-child(2n) {
  border-right: 0;
}

.page-about .about-band__dist {
  font-family: var(--yx-serif);
  font-weight: 600;
  font-size: clamp(1.05rem, 1.8vw, 1.25rem);
  color: #fff;
  letter-spacing: 0.04em;
}

.page-about .about-band__note {
  font-size: 0.74rem;
  letter-spacing: 0.1em;
  color: var(--yx-orange);
}

.page-about .about-band__foot {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: clamp(14px, 2vw, 20px) clamp(12px, 2vw, 18px);
  background: rgba(7, 46, 78, 0.4);
}

.page-about .about-band__kpi {
  font-size: clamp(1.6rem, 3.4vw, 2.2rem);
  font-weight: 500;
  color: #fff;
  line-height: 1;
}

.page-about .about-band__kpilabel {
  font-size: 0.86rem;
  color: #C9DBEB;
}

.page-about .about-shanghai__figure {
  margin: clamp(24px, 3.4vw, 40px) 0 0;
}

.page-about .about-shanghai__figure .yx-figure__cap {
  color: #C9DBEB;
}

.page-about .about-shanghai__link {
  margin: clamp(18px, 2.6vw, 26px) 0 0;
  font-size: 0.95rem;
  color: #C9DBEB;
  max-width: 64ch;
}

.page-about .about-shanghai__link a {
  color: var(--yx-orange);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .about-shanghai__link a:hover {
  color: #fff;
}

/* ---------- 工程师 ---------- */
.page-about .about-team .yx-title {
  font-family: var(--yx-serif);
  margin: 0.15em 0 0.6em;
}

.page-about .about-team__text {
  margin: 0 0 1em;
  max-width: 68ch;
}

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

.page-about .about-team__stats {
  margin-top: clamp(28px, 4vw, 44px);
}

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

.page-about .about-statbox .yx-stat__value {
  font-family: var(--yx-mono);
  font-weight: 500;
  font-size: clamp(1.7rem, 3.6vw, 2.3rem);
  color: var(--yx-blue);
  display: block;
  line-height: 1.1;
}

.page-about .about-statbox .yx-stat__value small {
  font-family: var(--yx-sans);
  font-size: 0.44em;
  color: var(--yx-muted);
  margin-left: 4px;
}

.page-about .about-statbox .yx-stat__label {
  display: block;
  margin-top: 6px;
  font-size: 0.82rem;
  letter-spacing: 0.1em;
  color: var(--yx-muted);
}

/* ---------- 资质与合作 ---------- */
.page-about .about-creds .yx-title {
  font-family: var(--yx-serif);
  margin: 0.15em 0 0.5em;
}

.page-about .about-creds__grid {
  margin-top: clamp(24px, 3.4vw, 40px);
}

.page-about .about-cred {
  border: 1px solid var(--yx-line);
  border-top: 3px solid var(--yx-blue);
  background: var(--yx-paper);
  padding: clamp(16px, 2.2vw, 24px);
  display: flex;
  flex-direction: column;
  gap: 8px;
  transition: border-top-color 180ms var(--yx-ease), transform 180ms var(--yx-ease);
}

.page-about .about-cred:hover,
.page-about .about-cred:focus-within {
  border-top-color: var(--yx-orange);
  transform: translateY(-2px);
}

.page-about .about-cred .yx-card__index {
  font-size: 0.8rem;
  letter-spacing: 0.1em;
  color: var(--yx-orange-deep);
}

.page-about .about-cred .yx-card__title {
  font-family: var(--yx-serif);
  font-weight: 600;
  font-size: 1.02rem;
  line-height: 1.45;
  margin: 0;
}

.page-about .about-cred .yx-card__body {
  margin: 0;
  font-size: 0.9rem;
  color: var(--yx-muted);
}

.page-about .about-parts {
  margin-top: clamp(24px, 3.4vw, 40px);
  padding: clamp(18px, 2.6vw, 28px);
  background: var(--yx-pale);
  border-left: 4px solid var(--yx-orange);
}

.page-about .about-parts__lead {
  margin: 0;
  font-weight: 500;
  max-width: 70ch;
}

.page-about .about-parts__note {
  margin: 10px 0 0;
  font-size: 0.92rem;
  color: var(--yx-muted);
  max-width: 70ch;
}

.page-about .about-parts__note a {
  color: var(--yx-blue);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 下一阶段 ---------- */
.page-about .about-next .yx-title {
  font-family: var(--yx-serif);
  margin: 0.15em 0 0.6em;
}

.page-about .about-next__text {
  margin: 0 0 1em;
  max-width: 68ch;
}

.page-about .about-next__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: clamp(20px, 3vw, 30px) 0 0;
}

.page-about .about-next__panel {
  border: 1px solid var(--yx-line);
  background: var(--yx-paper);
  padding: clamp(18px, 2.6vw, 28px);
}

.page-about .about-next__panelTitle {
  font-family: var(--yx-serif);
  font-weight: 600;
  font-size: 1.05rem;
  margin: 0 0 14px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--yx-line);
}

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

.page-about .about-next__list li {
  display: grid;
  grid-template-columns: 26px 1fr;
  gap: 10px;
  font-size: 0.92rem;
  align-items: baseline;
}

.page-about .about-next__list .yx-mono {
  color: var(--yx-orange-deep);
  font-size: 0.8rem;
}

.page-about .about-next__list a {
  color: var(--yx-blue);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 图片通用 ---------- */
.page-about .yx-media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-band__list {
    grid-template-columns: repeat(3, 1fr);
  }

  .page-about .about-band__cell:nth-child(2n) {
    border-right: 1px solid rgba(201, 219, 235, 0.35);
  }

  .page-about .about-band__cell:nth-child(3n) {
    border-right: 0;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(260px, 0.6fr);
    align-items: end;
  }

  .page-about .about-band__list {
    grid-template-columns: repeat(6, 1fr);
  }

  .page-about .about-band__cell,
  .page-about .about-band__cell:nth-child(2n),
  .page-about .about-band__cell:nth-child(3n) {
    border-right: 1px solid rgba(201, 219, 235, 0.35);
  }

  .page-about .about-band__cell:last-child {
    border-right: 0;
  }

  /* 时间轴左右交错 */
  .page-about .about-tl::before {
    left: 50%;
  }

  .page-about .about-tl__item {
    display: grid;
    grid-template-columns: 1fr 1fr;
    column-gap: clamp(48px, 6vw, 84px);
    padding-left: 0;
  }

  .page-about .about-tl__item > .about-tl__card {
    grid-column: 1;
    justify-self: end;
    width: 100%;
  }

  .page-about .about-tl__item:nth-child(even) > .about-tl__card {
    grid-column: 2;
    justify-self: start;
  }

  .page-about .about-tl__marker {
    left: 50%;
    margin-left: -7px;
    top: 22px;
  }
}

@media (min-width: 1100px) {
  .page-about .about-origin__figure {
    align-self: start;
    position: sticky;
    top: calc(var(--yx-topbar-h) + 24px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-cred,
  .page-about .about-tl__card {
    transition: none;
  }

  .page-about .about-cred:hover,
  .page-about .about-cred:focus-within {
    transform: none;
  }
}