.page-about {
  --about-rail-w: 84px;
  --about-line: rgba(53, 227, 196, 0.22);
  background: var(--ink);
  color: var(--paper);
  overflow-x: clip;
}

/* ============ 首屏 ============ */
.page-about .about-hero {
  position: relative;
  padding: calc(var(--header-h) + 40px) 0 56px;
  background:
    radial-gradient(110% 80% at 88% -10%, rgba(53, 227, 196, 0.14), transparent 58%),
    radial-gradient(70% 60% at 6% 100%, rgba(240, 164, 74, 0.08), transparent 60%),
    linear-gradient(180deg, var(--ink-2) 0%, var(--ink) 100%);
  border-bottom: 1px solid var(--hair);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--cyan) 22%, transparent 62%);
  opacity: 0.5;
}

.page-about .breadcrumb {
  margin-bottom: 30px;
}

.page-about .breadcrumb ul {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  color: var(--muted);
}

.page-about .breadcrumb li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--muted);
  opacity: 0.55;
}

.page-about .breadcrumb a {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}

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

.page-about .breadcrumb li[aria-current="page"] {
  color: var(--paper);
}

.page-about .hero-grid {
  display: grid;
  gap: 32px;
}

.page-about .hero-copy {
  max-width: 68ch;
}

.page-about .about-kicker {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 20px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--orange);
}

.page-about .kicker-no {
  color: var(--orange);
}

.page-about .kicker-line {
  display: block;
  width: 42px;
  height: 1px;
  background: var(--cyan);
  opacity: 0.9;
}

.page-about .kicker-label {
  color: var(--muted);
}

.page-about .hero-title {
  margin: 0 0 22px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(30px, 5.2vw, 54px);
  line-height: 1.16;
  letter-spacing: -0.005em;
  color: var(--paper);
}

.page-about .hero-title::after {
  content: "";
  display: block;
  width: 72px;
  height: 3px;
  margin-top: 26px;
  background: var(--cyan);
}

.page-about .about-lede {
  margin: 0 0 30px;
  font-size: 17px;
  line-height: 1.78;
  color: var(--paper);
  opacity: 0.86;
  max-width: 62ch;
}

.page-about .hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .hero-meta {
  display: grid;
  gap: 0;
  align-self: start;
  border: 1px solid var(--hair-strong);
  border-radius: var(--radius);
  background: var(--glass);
  backdrop-filter: blur(6px);
  overflow: hidden;
}

.page-about .meta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 14px;
  justify-content: space-between;
  align-items: baseline;
  padding: 14px 18px;
  border-bottom: 1px solid var(--hair);
}

.page-about .meta-row:last-child {
  border-bottom: 0;
}

.page-about .meta-key {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.12em;
  color: var(--muted);
}

.page-about .meta-val {
  font-size: 14px;
  color: var(--paper);
  text-align: right;
}

/* ============ 通用区块 ============ */
.page-about .about-section {
  padding: 64px 0;
}

.page-about .section-head {
  gap: 14px;
  margin-bottom: 34px;
}

.page-about .about-section .section-no {
  font-family: var(--font-data);
  font-weight: 700;
  font-size: 22px;
  letter-spacing: -0.01em;
  color: var(--orange);
  padding-right: 14px;
  border-right: 2px solid var(--cyan);
  line-height: 1;
}

.page-about .about-section .section-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(24px, 3.4vw, 40px);
  line-height: 1.2;
  color: var(--paper);
}

.page-about .about-section .section-rule {
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--hair-strong), transparent);
  min-width: 40px;
}

.page-about .prose p {
  margin: 0 0 18px;
  font-size: 17px;
  line-height: 1.78;
  color: var(--paper);
  opacity: 0.88;
}

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

/* ============ 02 起源 ============ */
.page-about .about-section#origin {
  background:
    linear-gradient(180deg, var(--ink) 0%, var(--ink-2) 100%);
  border-top: 1px solid var(--hair);
  border-bottom: 1px solid var(--hair);
}

.page-about .origin-grid {
  display: grid;
  gap: 32px;
}

.page-about .origin-body {
  max-width: 66ch;
}

.page-about .origin-aside {
  padding: 24px 22px;
  border-radius: var(--radius);
  background: var(--glass);
  border: 1px solid var(--hair-strong);
  backdrop-filter: blur(6px);
  align-self: start;
}

.page-about .aside-title {
  margin: 0 0 18px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .aside-list {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .aside-list li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding-bottom: 12px;
  border-bottom: 1px dashed var(--hair-strong);
}

.page-about .aside-list li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .aside-num {
  font-family: var(--font-data);
  font-weight: 700;
  font-size: 30px;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--cyan);
  min-width: 2.2em;
}

.page-about .aside-label {
  font-size: 14px;
  color: var(--muted);
}

.page-about .aside-link {
  display: inline-block;
  font-size: 14px;
}

/* ============ 03 时间线 ============ */
.page-about .about-timeline {
  background: var(--ink);
}

.page-about .timeline {
  display: grid;
  gap: 28px;
}

.page-about .timeline-rail {
  display: none;
}

.page-about .timeline-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 34px;
  position: relative;
}

.page-about .timeline-item {
  position: relative;
  padding-left: 26px;
}

.page-about .timeline-item::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 14px;
  bottom: -34px;
  width: 1px;
  background: linear-gradient(180deg, var(--about-line), transparent 92%);
}

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

.page-about .timeline-node {
  position: absolute;
  left: 0;
  top: 8px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(53, 227, 196, 0.16);
}

.page-about .timeline-card {
  padding: 22px 22px 20px;
  border-radius: var(--radius);
  background: var(--ink-2);
  border: 1px solid var(--hair-strong);
  border-left: 2px solid var(--cyan);
}

.page-about .timeline-tag {
  display: inline-block;
  margin-bottom: 12px;
  padding: 3px 9px;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--orange);
  background: rgba(240, 164, 74, 0.1);
}

.page-about .timeline-title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 22px;
  line-height: 1.32;
  color: var(--paper);
}

.page-about .timeline-card p {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--paper);
  opacity: 0.84;
}

.page-about .timeline-figure {
  margin-top: 20px;
}

.page-about .timeline-item .media-caption {
  color: var(--muted);
}

/* ============ 图片框架微调 ============ */
.page-about .media-frame img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .media-caption {
  padding-top: 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.06em;
  color: var(--muted);
}

/* ============ 04 团队 ============ */
.page-about .about-teams {
  background: linear-gradient(180deg, var(--ink) 0%, var(--ink-2) 100%);
  border-top: 1px solid var(--hair);
  border-bottom: 1px solid var(--hair);
}

.page-about .team-photo {
  margin: 0 0 34px;
}

.page-about .team-grid {
  display: grid;
  gap: 20px;
}

.page-about .team-card {
  padding: 26px 22px;
  border-radius: var(--radius);
  background: var(--ink);
  border: 1px solid var(--hair-strong);
  position: relative;
}

.page-about .team-card::before {
  content: "";
  position: absolute;
  left: 22px;
  top: 0;
  width: 44px;
  height: 2px;
  background: var(--cyan);
}

.page-about .team-no {
  display: block;
  margin: 8px 0 6px;
  font-family: var(--font-data);
  font-weight: 700;
  font-size: 44px;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--orange);
}

.page-about .team-role {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 22px;
  line-height: 1.3;
  color: var(--paper);
}

.page-about .team-count {
  margin: 0 0 14px;
  font-family: var(--font-data);
  font-weight: 700;
  font-size: 17px;
  letter-spacing: 0.02em;
  color: var(--cyan);
}

.page-about .team-card p:last-child {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--paper);
  opacity: 0.84;
}

/* ============ 05 档案 ============ */
.page-about .archive-grid {
  display: grid;
  gap: 28px;
  margin-bottom: 34px;
}

.page-about .archive-copy {
  max-width: 66ch;
}

.page-about .archive-drawers {
  display: grid;
  gap: 12px;
  align-self: start;
}

.page-about .archive-drawer {
  border: 1px solid var(--hair-strong);
  border-radius: var(--radius-sm);
  background: var(--glass);
  backdrop-filter: blur(6px);
  overflow: hidden;
  transition: border-color 200ms var(--ease);
}

.page-about .archive-drawer[open] {
  border-color: rgba(53, 227, 196, 0.45);
}

.page-about .archive-drawer summary {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 15px 18px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 17px;
  color: var(--paper);
  user-select: none;
}

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

.page-about .archive-drawer summary::before {
  content: "";
  width: 8px;
  height: 8px;
  flex: none;
  border-radius: 1px;
  background: var(--cyan);
  transition: transform 200ms var(--ease);
}

.page-about .archive-drawer[open] summary::before {
  transform: rotate(45deg);
}

.page-about .drawer-body {
  padding: 0 18px 18px 36px;
  font-size: 15px;
  line-height: 1.78;
  color: var(--paper);
  opacity: 0.82;
}

.page-about .drawer-body p {
  margin: 0;
}

.page-about .archive-photo {
  margin: 0;
}

/* ============ 06 合作伙伴 ============ */
.page-about .about-partners {
  background: linear-gradient(180deg, var(--ink-2) 0%, var(--ink) 100%);
  border-top: 1px solid var(--hair);
  border-bottom: 1px solid var(--hair);
}

.page-about .partner-grid {
  display: grid;
  gap: 28px;
}

.page-about .partner-copy {
  max-width: 66ch;
}

.page-about .partner-cards {
  display: grid;
  gap: 14px;
  align-self: start;
}

.page-about .partner-card {
  padding: 18px 18px 16px;
  border-radius: var(--radius);
  background: var(--ink-2);
  border: 1px solid var(--hair-strong);
}

.page-about .partner-tag {
  margin-bottom: 10px;
  display: inline-block;
}

.page-about .partner-num {
  margin: 0 0 6px;
  font-family: var(--font-data);
  font-weight: 700;
  font-size: 34px;
  line-height: 1;
  letter-spacing: -0.015em;
  color: var(--cyan);
}

.page-about .partner-desc {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--paper);
  opacity: 0.8;
}

.page-about .partner-card--wide .partner-desc {
  font-size: 14.5px;
  opacity: 0.85;
}

/* ============ 07 服务对象 ============ */
.page-about .audience-lede {
  max-width: 72ch;
  margin: 0 0 32px;
  font-size: 17px;
  line-height: 1.78;
  color: var(--paper);
  opacity: 0.88;
}

.page-about .data-strip {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--hair-strong);
  border: 1px solid var(--hair-strong);
  border-radius: var(--radius);
  overflow: hidden;
  margin-bottom: 32px;
}

.page-about .data-cell {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 22px 20px;
  background: var(--ink-2);
}

.page-about .data-value {
  font-family: var(--font-data);
  font-weight: 700;
  font-size: clamp(34px, 5vw, 52px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--paper);
  display: inline-flex;
  align-items: baseline;
  gap: 4px;
}

.page-about .data-unit {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.06em;
  color: var(--cyan);
}

.page-about .data-label {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  color: var(--muted);
}

.page-about .audience-notes {
  display: grid;
  gap: 16px;
}

.page-about .audience-note {
  margin: 0;
  padding-left: 18px;
  border-left: 2px solid var(--about-line);
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--paper);
  opacity: 0.82;
}

/* ============ CTA ============ */
.page-about .about-cta {
  padding: 68px 0 84px;
  background:
    radial-gradient(80% 70% at 20% 0%, rgba(53, 227, 196, 0.1), transparent 60%),
    var(--ink);
}

.page-about .cta-panel {
  display: grid;
  gap: 26px;
  padding: 34px 26px;
  border-radius: var(--radius);
  background: var(--glass);
  border: 1px solid var(--hair-strong);
  backdrop-filter: blur(8px);
  position: relative;
}

.page-about .cta-panel::before {
  content: "";
  position: absolute;
  left: 26px;
  top: -1px;
  width: 56px;
  height: 2px;
  background: var(--orange);
}

.page-about .cta-kicker {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--orange);
}

.page-about .cta-title {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(24px, 3.6vw, 38px);
  line-height: 1.2;
  color: var(--paper);
}

.page-about .cta-text {
  margin: 0;
  font-size: 16px;
  line-height: 1.78;
  color: var(--paper);
  opacity: 0.84;
  max-width: 62ch;
}

.page-about .cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-content: start;
}

/* ============ 响应式 ============ */
@media (min-width: 760px) {
  .page-about .about-hero {
    padding: calc(var(--header-h) + 64px) 0 72px;
  }

  .page-about .hero-grid {
    grid-template-columns: minmax(0, 1.6fr) minmax(240px, 0.9fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .hero-meta {
    margin-top: 6px;
  }

  .page-about .about-section {
    padding: 84px 0;
  }

  .page-about .origin-grid {
    grid-template-columns: minmax(0, 1.7fr) minmax(250px, 0.9fr);
    gap: 46px;
  }

  .page-about .team-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 22px;
  }

  .page-about .archive-grid {
    grid-template-columns: minmax(0, 1.35fr) minmax(280px, 1fr);
    gap: 40px;
  }

  .page-about .archive-photo {
    margin-top: 8px;
  }

  .page-about .partner-grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(280px, 1fr);
    gap: 44px;
  }

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

  .page-about .audience-notes {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px;
  }

  .page-about .cta-panel {
    grid-template-columns: minmax(0, 1.6fr) minmax(220px, auto);
    align-items: center;
    padding: 42px 40px;
    gap: 36px;
  }

  .page-about .cta-panel::before {
    left: 40px;
  }

  .page-about .cta-actions {
    justify-content: flex-end;
  }
}

@media (min-width: 1024px) {
  .page-about .timeline {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: 44px;
  }

  .page-about .timeline-rail {
    display: flex;
    flex-direction: column;
    gap: 20px;
    position: sticky;
    top: calc(var(--header-h) + 48px);
    align-self: start;
    padding-top: 4px;
    border-left: 1px solid var(--hair-strong);
    padding-left: 18px;
  }

  .page-about .rail-link {
    display: block;
    font-family: var(--font-data);
    font-weight: 700;
    font-size: 22px;
    letter-spacing: -0.01em;
    line-height: 1;
    color: var(--muted);
    text-decoration: none;
    transition: color 160ms var(--ease), transform 160ms var(--ease);
  }

  .page-about .rail-link::before {
    content: "";
    display: inline-block;
    width: 0;
    height: 2px;
    margin-right: 0;
    vertical-align: middle;
    background: var(--cyan);
    transition: width 200ms var(--ease), margin-right 200ms var(--ease);
  }

  .page-about .rail-link:hover {
    color: var(--paper);
  }

  .page-about .rail-link.is-current {
    color: var(--cyan);
  }

  .page-about .rail-link.is-current::before {
    width: 18px;
    margin-right: 8px;
  }

  .page-about .timeline-list {
    gap: 46px;
  }

  .page-about .timeline-item {
    padding-left: 34px;
  }

  .page-about .timeline-item::before {
    left: 6px;
  }

  .page-about .timeline-node {
    left: 1px;
  }

  .page-about .timeline-card {
    padding: 26px 28px 24px;
  }

  .page-about .timeline-title {
    font-size: 24px;
  }

  .page-about .origin-aside {
    padding: 28px 26px;
  }
}

@media (min-width: 1200px) {
  .page-about .about-section {
    padding: 96px 0;
  }

  .page-about .hero-grid {
    grid-template-columns: minmax(0, 1.7fr) minmax(260px, 0.85fr);
    gap: 56px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .rail-link,
  .page-about .rail-link::before,
  .page-about .breadcrumb a,
  .page-about .archive-drawer summary::before {
    transition: none;
  }
}