.page-about {
  display: block;
  background: linear-gradient(180deg, #06130f 0%, var(--deep) 34%, #04100d 100%);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(22px, 4vw, 46px) 0 clamp(32px, 4.6vw, 58px);
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(110% 85% at 94% 0%, rgba(0, 229, 255, 0.16), transparent 58%),
    radial-gradient(85% 70% at 0% 100%, rgba(255, 90, 31, 0.13), transparent 62%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 12px;
  background-image: repeating-linear-gradient(
    90deg,
    rgba(0, 229, 255, 0.34) 0 1px,
    transparent 1px 28px
  );
  opacity: 0.55;
  pointer-events: none;
}

.page-about .breadcrumbs {
  margin-bottom: clamp(18px, 3vw, 30px);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3.4vw, 40px);
}

.page-about .about-hero__title {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(32px, 7vw, 74px);
  line-height: 1.02;
  letter-spacing: -0.005em;
  color: var(--paper);
}

.page-about .about-hero__text {
  margin: 16px 0 0;
  max-width: 56ch;
  font-size: var(--step-1);
  line-height: 1.72;
  color: var(--grey);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

.page-about .about-hero__facts {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--glass-fill);
  padding: 16px 18px;
  backdrop-filter: blur(10px);
}

.page-about .fact-list {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
  display: grid;
  gap: 11px;
}

.page-about .fact-item {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .fact-item:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}

.page-about .fact-num {
  font-family: var(--font-mono);
  font-size: clamp(19px, 2.4vw, 24px);
  letter-spacing: -0.02em;
  color: var(--cyan);
  white-space: nowrap;
}

.page-about .fact-key {
  font-size: var(--step--1);
  color: var(--grey);
  text-align: right;
}

/* ---------- 通用区块头 ---------- */
.page-about .about-section-head {
  max-width: 64ch;
  margin: 0 0 clamp(20px, 3vw, 32px);
}

.page-about .about-section-head .section-title {
  margin: 10px 0 12px;
}

/* ---------- 时间轨道 ---------- */
.page-about .about-timeline {
  padding: clamp(36px, 6vw, 76px) 0;
  border-bottom: 1px solid var(--line-soft);
}

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

.page-about .rail-index {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(155, 246, 255, 0.05);
  padding: 8px;
}

.page-about .rail-index ol {
  display: flex;
  gap: 6px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .rail-index a {
  display: block;
  padding: 7px 12px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--grey);
  text-decoration: none;
  white-space: nowrap;
  border-left: 2px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .rail-index a:hover,
.page-about .rail-index a:focus-visible {
  color: var(--cyan);
  border-left-color: var(--whistle);
  outline: none;
}

.page-about .rail-stops {
  display: grid;
  gap: 13px;
  min-width: 0;
}

.page-about .stop {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
}

.page-about .stop::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: linear-gradient(180deg, var(--cyan), var(--whistle));
  opacity: 0.85;
}

.page-about .stop[open] {
  border-color: rgba(0, 229, 255, 0.32);
}

.page-about .stop-summary {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 15px 18px 15px 22px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .stop-summary::after {
  content: "";
  flex: 0 0 auto;
  align-self: center;
  width: 9px;
  height: 9px;
  border-right: 2px solid var(--cyan);
  border-bottom: 2px solid var(--cyan);
  transform: rotate(45deg);
  transition: transform 0.25s var(--ease);
}

.page-about .stop[open] .stop-summary::after {
  transform: rotate(-135deg);
}

.page-about .stop-year {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--whistle);
}

.page-about .stop-title {
  flex: 1 1 auto;
  min-width: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(17px, 2.3vw, 24px);
  line-height: 1.3;
  color: var(--paper);
  transition: color 0.2s var(--ease);
}

.page-about .stop-summary:hover .stop-title {
  color: var(--cyan);
}

.page-about .stop-body {
  padding: 0 20px 20px 22px;
}

.page-about .stop-body p {
  margin: 0;
  max-width: 64ch;
  font-size: var(--step-0);
  line-height: 1.78;
  color: var(--paper);
}

/* ---------- 图片框 ---------- */
.page-about .about-figure {
  margin: 18px 0 0;
  min-width: 0;
}

.page-about .media-frame {
  aspect-ratio: 3 / 2;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--ink);
}

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

.page-about .media-caption {
  display: block;
  margin-top: 8px;
  font-size: var(--step--1);
  line-height: 1.6;
  color: var(--grey);
}

/* ---------- 数据 ---------- */
.page-about .about-data {
  padding: clamp(34px, 5.5vw, 72px) 0;
  border-bottom: 1px solid var(--line-soft);
}

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

.page-about .data-cell {
  display: flex;
  flex-direction: column;
  gap: 7px;
  padding: 16px 14px;
  background: var(--deep);
}

.page-about .data-num {
  display: flex;
  align-items: baseline;
  gap: 4px;
  font-family: var(--font-mono);
  font-size: clamp(26px, 4.2vw, 42px);
  font-weight: 600;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--cyan);
}

.page-about .data-unit {
  font-size: 0.42em;
  color: var(--glass);
}

.page-about .data-key {
  font-size: var(--step--1);
  line-height: 1.5;
  color: var(--grey);
}

.page-about .tag[data-tone="yellow"] {
  background: rgba(255, 210, 63, 0.16);
  border: 1px solid rgba(255, 210, 63, 0.42);
  color: var(--card-yellow);
  margin-left: 2px;
}

.page-about .about-data__note {
  margin: 18px 0 0;
  max-width: 64ch;
  font-size: var(--step--1);
  line-height: 1.75;
  color: var(--grey);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  padding: clamp(34px, 5.5vw, 72px) 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-team__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}

.page-about .about-team__text .section-title {
  margin: 10px 0 12px;
}

.page-about .crew-grid {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .crew {
  border: 1px solid var(--line);
  border-left: 3px solid var(--cyan);
  border-radius: var(--radius);
  background: var(--panel);
  padding: 14px 16px;
}

.page-about .crew:nth-child(2) {
  border-left-color: var(--whistle);
}

.page-about .crew:nth-child(3) {
  border-left-color: var(--glass);
}

.page-about .crew:nth-child(4) {
  border-left-color: var(--grey);
}

.page-about .crew h3 {
  margin: 0 0 7px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--step-1);
  letter-spacing: 0.01em;
  color: var(--paper);
}

.page-about .crew p {
  margin: 0;
  font-size: var(--step--1);
  line-height: 1.72;
  color: var(--grey);
}

/* ---------- 合作生态 ---------- */
.page-about .about-partners {
  padding: clamp(34px, 5.5vw, 72px) 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .partner-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .partner {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding: 16px 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .partner:last-child {
  border-bottom: 1px solid var(--line-soft);
}

.page-about .partner-dot {
  display: grid;
  place-items: center;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  font-family: var(--font-mono);
  font-size: 17px;
  font-weight: 600;
  color: var(--ink);
  background: var(--cyan);
}

.page-about .partner:nth-child(2) .partner-dot {
  background: var(--whistle);
}

.page-about .partner:nth-child(3) .partner-dot {
  background: var(--glass);
}

.page-about .partner h3 {
  margin: 2px 0 6px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--step-1);
  color: var(--paper);
}

.page-about .partner p {
  margin: 0;
  font-size: var(--step--1);
  line-height: 1.75;
  color: var(--grey);
}

/* ---------- 服务区域 ---------- */
.page-about .about-region {
  padding: clamp(34px, 5.5vw, 72px) 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-region__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  align-items: center;
}

.page-about .about-region .section-title {
  margin: 10px 0 12px;
}

.page-about .region-card {
  margin-top: 18px;
  padding: 15px 18px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--whistle);
  border-radius: var(--radius);
  background: var(--glass-fill);
}

.page-about .region-key {
  margin: 0 0 7px;
  font-size: var(--step--2);
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--grey);
}

.page-about .region-value {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--step--1);
  line-height: 1.7;
  color: var(--paper);
}

.page-about .about-region__note {
  margin: 14px 0 0;
  font-size: var(--step--1);
  line-height: 1.7;
  color: var(--grey);
}

.page-about .about-region__note a {
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 资质 ---------- */
.page-about .about-credentials {
  padding: clamp(34px, 5.5vw, 72px) 0;
}

.page-about .cred-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.page-about .cred {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  padding: 16px;
}

.page-about .cred-num {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: clamp(19px, 2.8vw, 28px);
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--cyan);
}

.page-about .cred h3 {
  margin: 0 0 7px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--step-0);
  line-height: 1.35;
  color: var(--paper);
}

.page-about .cred p {
  margin: 0;
  font-size: var(--step--1);
  line-height: 1.7;
  color: var(--grey);
}

/* ---------- 收尾 ---------- */
.page-about .about-next {
  padding: clamp(28px, 4.5vw, 52px) 0 clamp(40px, 6vw, 74px);
}

.page-about .about-next__inner {
  display: grid;
  gap: 14px;
  padding: clamp(20px, 3.4vw, 34px);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  background:
    linear-gradient(120deg, rgba(0, 229, 255, 0.12), rgba(255, 90, 31, 0.12)),
    var(--panel);
}

.page-about .about-next__inner .section-title {
  margin: 0;
}

.page-about .about-next__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 4px;
}

/* ---------- 媒体查询 ---------- */
@media (min-width: 720px) {
  .page-about .crew-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

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

  .page-about .about-team__grid,
  .page-about .about-region__grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: clamp(24px, 3.6vw, 40px);
  }

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

  .page-about .data-cell {
    padding: 22px 18px;
  }
}

@media (min-width: 960px) {
  .page-about .rail {
    grid-template-columns: 116px minmax(0, 1fr);
    gap: clamp(20px, 2.6vw, 34px);
    align-items: start;
  }

  .page-about .rail-index {
    position: sticky;
    top: calc(var(--header-h) + 22px);
    overflow: visible;
    padding: 10px 6px;
  }

  .page-about .rail-index ol {
    flex-direction: column;
    gap: 2px;
  }

  .page-about .rail-index a {
    padding: 8px 10px;
  }

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

@media (max-width: 420px) {
  .page-about .stop-summary {
    flex-wrap: wrap;
    gap: 6px 10px;
    padding: 14px 14px 14px 18px;
  }

  .page-about .stop-summary::after {
    margin-left: auto;
  }

  .page-about .stop-body {
    padding: 0 16px 18px 18px;
  }

  .page-about .partner {
    grid-template-columns: 46px minmax(0, 1fr);
    gap: 12px;
  }

  .page-about .partner-dot {
    width: 46px;
    height: 46px;
    font-size: 15px;
  }
}