.page-about {
  --about-measure: 66ch;
  --about-rule: 1px solid var(--steel-600);
  --about-soft: rgba(42, 74, 117, 0.55);
  padding-bottom: clamp(56px, 9vw, 128px);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-top: clamp(36px, 6vw, 76px);
  padding-bottom: clamp(32px, 5vw, 64px);
  background:
    radial-gradient(820px 400px at 82% -12%, rgba(34, 224, 255, 0.15), transparent 70%),
    radial-gradient(560px 300px at 4% 12%, rgba(123, 255, 60, 0.07), transparent 72%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: -180px;
  right: -170px;
  width: 540px;
  height: 540px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(34, 224, 255, 0.14), transparent 68%);
  pointer-events: none;
}

@media (prefers-reduced-motion: no-preference) {
  .page-about .about-hero::after {
    animation: aboutGlow 17s ease-in-out infinite alternate;
  }

  @keyframes aboutGlow {
    from { transform: translate3d(0, 0, 0); }
    to { transform: translate3d(-70px, 80px, 0); }
  }
}

.page-about .crumbs {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: clamp(22px, 3.6vw, 42px);
  font-size: var(--fs-14);
  color: var(--mist-400);
}

.page-about .crumbs a {
  color: var(--mist-400);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.page-about .crumbs a:hover,
.page-about .crumbs a:focus-visible {
  color: var(--cyan-400);
  border-bottom-color: var(--cyan-400);
}

.page-about .about-hero__frame {
  position: relative;
  z-index: 1;
  padding: clamp(26px, 5vw, 62px) clamp(20px, 4.4vw, 58px);
}

.page-about .about-hero__title {
  margin: 20px 0 0;
  font-size: clamp(32px, 7vw, 82px);
  line-height: 1.04;
  color: var(--white-100);
}

.page-about .about-hero__lede {
  max-width: var(--about-measure);
  margin: clamp(20px, 3vw, 34px) 0 0;
  font-size: clamp(16px, 1.5vw, 18px);
  line-height: 1.85;
  color: var(--mist-400);
}

.page-about .about-hero__meta {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(28px, 4.6vw, 52px) 0 0;
  background: var(--about-soft);
  border: var(--about-rule);
}

.page-about .about-figure {
  background: var(--navy-900);
  padding: clamp(14px, 2vw, 22px) clamp(14px, 2vw, 20px);
}

.page-about .about-figure__cap {
  margin: 0 0 8px;
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--mist-400);
}

.page-about .about-figure__num {
  margin: 0;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(24px, 3.4vw, 38px);
  line-height: 1;
  font-weight: 700;
  color: var(--cyan-400);
}

.page-about .about-figure__num span {
  display: block;
  margin-top: 6px;
  font-family: var(--font-sans);
  font-size: var(--fs-12);
  font-weight: 400;
  letter-spacing: 0.1em;
  color: var(--mist-400);
}

/* ---------- 纵向刻度主线 ---------- */

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

@media (min-width: 900px) {
  .page-about .about-spine {
    padding-left: clamp(52px, 6vw, 96px);
  }

  .page-about .about-spine::before {
    content: "";
    position: absolute;
    top: 0;
    bottom: 0;
    left: clamp(12px, 2vw, 28px);
    width: 1px;
    background: repeating-linear-gradient(
      to bottom,
      var(--steel-600) 0 10px,
      transparent 10px 20px
    );
  }
}

/* ---------- 通用文字块 ---------- */

.page-about .about-block {
  position: relative;
  padding-block: clamp(34px, 5.4vw, 68px);
}

.page-about .about-block > h2,
.page-about .about-block__text > h2 {
  margin: 0 0 clamp(14px, 2.2vw, 24px);
  font-size: clamp(23px, 3.6vw, 42px);
  line-height: 1.14;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--white-100);
}

.page-about .about-block > h2::before,
.page-about .about-block__text > h2::before {
  content: "";
  display: block;
  width: 46px;
  height: 3px;
  margin-bottom: 14px;
  background: var(--green-400);
}

.page-about .about-block p {
  max-width: var(--about-measure);
  margin: 0 0 1.05em;
  font-size: clamp(15px, 1.1vw, 17px);
  line-height: 1.85;
  color: var(--mist-400);
}

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

.page-about .about-block__lead {
  color: var(--white-100) !important;
  font-size: clamp(16px, 1.3vw, 18px) !important;
}

/* ---------- 图片 ---------- */

.page-about .about-media {
  margin: clamp(26px, 4.4vw, 54px) 0;
}

.page-about .about-media.media-frame {
  overflow: hidden;
  border: var(--about-rule);
  background: linear-gradient(150deg, var(--navy-700), var(--navy-900));
}

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

.page-about .media-frame--wide {
  aspect-ratio: 14 / 9;
}

.page-about .media-frame--square {
  aspect-ratio: 1 / 1;
}

/* ---------- 时间轴 ---------- */

.page-about .about-timeline {
  position: relative;
  margin: clamp(22px, 3vw, 36px) 0 0;
  padding: 0 0 0 clamp(24px, 4vw, 42px);
  list-style: none;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  top: 8px;
  bottom: 8px;
  left: 0;
  width: 1px;
  background: linear-gradient(to bottom, var(--cyan-400), rgba(34, 224, 255, 0.12));
}

.page-about .about-timeline__item {
  position: relative;
  padding-bottom: clamp(26px, 3.6vw, 42px);
}

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

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  top: 10px;
  left: calc(-1 * clamp(24px, 4vw, 42px) - 6px);
  width: 12px;
  height: 12px;
  background: var(--navy-900);
  border: 1px solid var(--cyan-400);
  transform: rotate(45deg);
  transition: background 0.22s ease, border-color 0.22s ease, box-shadow 0.22s ease;
}

.page-about .about-timeline__item:hover::before {
  background: var(--green-400);
  border-color: var(--green-400);
  box-shadow: var(--glow-cyan);
}

.page-about .about-timeline__year {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(26px, 4.4vw, 46px);
  line-height: 1;
  font-weight: 700;
  color: var(--cyan-400);
}

.page-about .about-timeline__item h3 {
  margin: 10px 0 6px;
  font-size: clamp(17px, 1.8vw, 22px);
  font-weight: 700;
  color: var(--white-100);
}

.page-about .about-timeline__item p {
  max-width: 54ch;
  margin: 0;
}

.page-about .about-timeline__tag {
  display: inline-block;
  margin-top: 12px;
  padding: 5px 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--mist-400);
  border: var(--about-rule);
  opacity: 0.55;
  transition: opacity 0.22s ease, color 0.22s ease, border-color 0.22s ease;
}

.page-about .about-timeline__item:hover .about-timeline__tag,
.page-about .about-timeline__item:focus-within .about-timeline__tag {
  opacity: 1;
  color: var(--green-400);
  border-color: var(--green-400);
}

/* ---------- 展签式说明牌 ---------- */

.page-about .about-specs {
  display: grid;
  gap: 12px;
  margin-top: clamp(20px, 3vw, 32px);
}

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

.page-about .about-spec {
  padding: 16px 18px;
  border: var(--about-rule);
  background: linear-gradient(158deg, rgba(18, 58, 107, 0.6), rgba(10, 26, 51, 0.94));
  transition: border-color 0.2s ease, box-shadow 0.2s ease, transform 0.2s ease;
}

.page-about .about-spec:hover {
  border-color: var(--cyan-400);
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-hard);
}

.page-about .about-spec[open] {
  border-left: 2px solid var(--green-400);
}

.page-about .about-spec > summary {
  display: flex;
  align-items: baseline;
  gap: 10px;
  cursor: pointer;
  list-style: none;
  font-size: var(--fs-16);
  font-weight: 700;
  color: var(--white-100);
}

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

.page-about .about-spec > summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: var(--fs-18);
  line-height: 1;
  color: var(--cyan-400);
}

.page-about .about-spec[open] > summary::after {
  content: "–";
  color: var(--green-400);
}

.page-about .about-spec__num {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.14em;
  color: var(--cyan-400);
}

.page-about .about-spec p {
  margin: 12px 0 0;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--mist-400);
}

/* ---------- 图文分栏 ---------- */

@media (min-width: 900px) {
  .page-about .about-block--split {
    display: grid;
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    gap: clamp(28px, 4.4vw, 68px);
    align-items: start;
  }

  .page-about .about-block--split .about-media {
    margin: 0;
  }
}

/* ---------- 维度切换表 ---------- */

.page-about .about-switch {
  position: relative;
  margin-top: clamp(22px, 3.2vw, 38px);
}

.page-about .about-switch__input {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}

.page-about .about-switch__tabs {
  display: inline-flex;
  margin-bottom: 22px;
  border: var(--about-rule);
}

.page-about .about-switch__tabs label {
  padding: 11px 20px;
  font-size: var(--fs-14);
  letter-spacing: 0.08em;
  color: var(--mist-400);
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease;
}

.page-about .about-switch__tabs label + label {
  border-left: var(--about-rule);
}

.page-about .about-switch__tabs label:hover {
  color: var(--cyan-400);
}

.page-about #about-dim-a:checked ~ .about-switch__tabs label[for="about-dim-a"],
.page-about #about-dim-b:checked ~ .about-switch__tabs label[for="about-dim-b"] {
  background: var(--green-400);
  color: var(--navy-900);
  font-weight: 700;
}

.page-about .about-table {
  width: 100%;
  border-collapse: collapse;
  font-size: clamp(14px, 1vw, 16px);
}

.page-about .about-table__cap {
  padding: 0 0 12px;
  text-align: left;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.18em;
  color: var(--cyan-400);
}

.page-about .about-table th,
.page-about .about-table td {
  padding: 14px 16px;
  text-align: left;
  border-bottom: 1px solid var(--about-soft);
}

.page-about .about-table th {
  width: 56%;
  font-weight: 500;
  color: var(--mist-400);
}

.page-about .about-table td {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  color: var(--white-100);
  white-space: nowrap;
}

.page-about .about-table tbody tr:nth-child(odd) {
  background: rgba(18, 58, 107, 0.24);
}

.page-about .about-table--b {
  display: none;
}

.page-about #about-dim-b:checked ~ .about-switch__panels .about-table--a {
  display: none;
}

.page-about #about-dim-b:checked ~ .about-switch__panels .about-table--b {
  display: table;
}

/* ---------- 上海反白内容带 ---------- */

.page-about .about-shanghai {
  display: grid;
  gap: clamp(20px, 3vw, 36px);
  margin-top: clamp(22px, 3.2vw, 38px);
}

@media (min-width: 900px) {
  .page-about .about-shanghai {
    grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.05fr);
    align-items: center;
  }

  .page-about .about-shanghai .about-media {
    margin: 0;
  }
}

.page-about .about-band {
  position: relative;
  padding: clamp(24px, 3.6vw, 44px);
  background: var(--paper-000);
  box-shadow: var(--shadow-hard);
}

.page-about .about-band::before {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  width: 6px;
  background: var(--orange-500);
}

.page-about .about-band .label {
  color: var(--trench-500);
}

.page-about .about-band__lead {
  margin: 14px 0 18px;
  max-width: 40ch;
  font-size: clamp(16px, 1.4vw, 19px);
  line-height: 1.75;
  font-weight: 700;
  color: var(--navy-900);
}

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

.page-about .about-band__list li {
  padding: 12px 0 12px 18px;
  border-top: 1px solid rgba(18, 58, 107, 0.22);
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--trench-500);
}

.page-about .about-band__list li strong {
  display: inline-block;
  margin-right: 8px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.12em;
  color: var(--navy-900);
}

.page-about .about-shanghai__media {
  clip-path: polygon(0 0, 100% 3%, 100% 100%, 0 97%);
}

/* ---------- 合作入口 ---------- */

.page-about .about-block--cta {
  padding-bottom: clamp(10px, 2vw, 24px);
}

.page-about .about-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: clamp(22px, 3vw, 34px);
}

.page-about .about-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 30px;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 20px 0 0;
  list-style: none;
  border-top: 1px solid var(--about-soft);
}

/* ---------- 窄屏兜底 ---------- */

@media (max-width: 560px) {
  .page-about .about-switch__tabs {
    display: flex;
    width: 100%;
  }

  .page-about .about-switch__tabs label {
    flex: 1 1 0;
    text-align: center;
    padding: 11px 8px;
    font-size: var(--fs-12);
  }

  .page-about .about-table th,
  .page-about .about-table td {
    padding: 12px 10px;
  }

  .page-about .about-table td {
    white-space: normal;
  }

  .page-about .about-shanghai__media {
    clip-path: none;
  }
}