.page-about {
  --story-rail-w: 220px;
  background: var(--bg-deep);
  color: var(--text);
}

/* ===== 首屏框景封面 ===== */
.page-about .story-hero {
  margin-top: calc(var(--header-h) * -1);
  padding: var(--header-h) 0 0;
  background: var(--bg-deep);
}
.page-about .story-hero-frame {
  width: min(calc(100% - 20px), var(--content-max));
  margin: 0 auto;
  border: 1px solid var(--border);
  box-shadow: 0 18px 60px rgba(0, 0, 0, 0.35);
  display: flex;
  flex-direction: column;
}
.page-about .story-hero-axis {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 8px 12px;
  font-size: 10px;
  font-weight: 800;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-faint);
  background: rgba(16, 24, 40, 0.5);
  border-bottom: 1px solid var(--border);
}
.page-about .story-hero-axis.bottom {
  border-bottom: 0;
  border-top: 1px solid var(--border);
}
.page-about .story-hero-window {
  position: relative;
  min-height: 520px;
  overflow: hidden;
  display: flex;
  align-items: flex-end;
}
.page-about .story-hero-media {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.page-about .story-hero-veil {
  position: absolute;
  inset: 0;
  z-index: 1;
  background:
    linear-gradient(180deg, rgba(11, 29, 58, 0.68) 0%, rgba(11, 29, 58, 0.35) 38%, rgba(11, 29, 58, 0.92) 100%),
    radial-gradient(circle at 84% 14%, rgba(166, 77, 244, 0.28) 0%, transparent 42%);
}
.page-about .story-hero-content {
  position: relative;
  z-index: 2;
  width: 100%;
  padding: 28px 20px 24px;
}
.page-about .story-hero-content .breadcrumbs {
  margin-bottom: 24px;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--text-faint);
}
.page-about .story-hero-title {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(2rem, 5vw, 3.6rem);
  line-height: 1.02;
  letter-spacing: -0.03em;
  color: var(--text);
}
.page-about .story-hero-lead {
  margin: 10px 0 0;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(1.05rem, 2vw, 1.5rem);
  color: var(--purple);
  letter-spacing: -0.01em;
}
.page-about .story-hero-desc {
  margin: 18px 0 0;
  max-width: 620px;
  font-size: 16px;
  line-height: 1.75;
  color: var(--text-dim);
}
.page-about .story-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}
.page-about .hero-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px 20px;
  margin-top: 28px;
  padding-top: 22px;
  border-top: 1px solid var(--border);
}
.page-about .hero-stat {
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.page-about .hero-stat-num {
  font-family: var(--font-body);
  font-weight: 800;
  font-size: 1.65rem;
  line-height: 1.05;
  color: var(--accent);
  letter-spacing: -0.02em;
}
.page-about .hero-stat-label {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-faint);
}

/* ===== 纵向层叠布局：左侧章节导航 ===== */
.page-about .story-layout {
  padding: 64px 0 96px;
}
.page-about .story-layout-inner {
  width: min(calc(100% - 20px), var(--content-max));
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}
.page-about .story-rail {
  position: relative;
  z-index: 3;
  border: 1px solid var(--border);
  background: rgba(26, 58, 110, 0.5);
  border-radius: var(--radius);
  padding: 16px;
}
.page-about .rail-caption {
  margin: 0 0 10px;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--text-faint);
}
.page-about .rail-nav {
  display: flex;
  gap: 8px;
  overflow-x: auto;
}
.page-about .rail-link {
  display: flex;
  align-items: center;
  gap: 8px;
  flex: 0 0 auto;
  padding: 8px 12px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  color: var(--text-dim);
  font-size: 13px;
  font-weight: 700;
  white-space: nowrap;
  text-decoration: none;
  transition: background-color 0.2s, color 0.2s;
}
.page-about .rail-link:hover,
.page-about .rail-link:focus-visible {
  color: var(--text);
  background: rgba(255, 255, 255, 0.06);
}
.page-about .rail-index {
  font-size: 10px;
  font-weight: 800;
  color: var(--text-faint);
}
.page-about .rail-dot {
  width: 6px;
  height: 6px;
  border-radius: 999px;
  background: var(--purple);
  opacity: 0.45;
}
.page-about .rail-footer {
  display: none;
}

/* ===== 章节通用排版 ===== */
.page-about .story-main .story-section {
  scroll-margin-top: calc(var(--header-h) + 32px);
}
.page-about .story-section + .story-section {
  margin-top: 72px;
  padding-top: 64px;
  border-top: 1px solid var(--border);
}
.page-about .section-head {
  position: relative;
  margin-bottom: 36px;
}
.page-about .section-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  border: 1px solid var(--border);
  border-radius: 999px;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
}
.page-about .section-tag::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 999px;
  background: var(--purple);
}
.page-about .section-title {
  margin: 14px 0 0;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.6rem, 3vw, 2.5rem);
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--text);
}
.page-about .section-desc {
  margin: 12px 0 0;
  max-width: 640px;
  font-size: 16px;
  line-height: 1.7;
  color: var(--text-dim);
}

/* ===== 发展里程碑时间线 ===== */
.page-about .milestone-timeline {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 24px;
}
.page-about .milestone-timeline::before {
  content: '';
  position: absolute;
  left: 15px;
  top: 44px;
  bottom: 44px;
  width: 1px;
  background: linear-gradient(180deg, var(--accent), var(--purple));
  opacity: 0.5;
}
.page-about .milestone-item {
  position: relative;
  display: grid;
  grid-template-columns: 32px minmax(0, 1fr);
  gap: 16px;
}
.page-about .milestone-marker {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  padding-top: 4px;
}
.page-about .milestone-year {
  font-family: var(--font-body);
  font-weight: 800;
  font-size: 13px;
  white-space: nowrap;
  color: var(--purple);
}
.page-about .milestone-core {
  width: 14px;
  height: 14px;
  border-radius: 999px;
  background: var(--purple);
  box-shadow: 0 0 0 4px rgba(166, 77, 244, 0.18);
  z-index: 1;
}
.page-about .milestone-panel {
  background: linear-gradient(145deg, rgba(26, 58, 110, 0.8), rgba(26, 58, 110, 0.4));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  transition: transform 0.2s ease, border-color 0.2s ease;
}
.page-about .milestone-panel:hover {
  transform: translateY(-2px);
  border-color: rgba(255, 106, 0, 0.5);
}
.page-about .milestone-panel h3 {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 1.1rem;
  color: var(--text);
}
.page-about .milestone-panel p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-dim);
}
.page-about .milestone-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}

/* ===== 核心团队与组织 ===== */
.page-about .team-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}
.page-about .team-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.page-about .team-item {
  display: grid;
  grid-template-columns: 36px minmax(0, 1fr);
  gap: 14px;
  padding: 16px;
  background: rgba(26, 58, 110, 0.42);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.page-about .team-num {
  font-family: var(--font-body);
  font-weight: 800;
  font-size: 1.3rem;
  line-height: 1;
  color: var(--accent);
}
.page-about .team-entry strong {
  display: block;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 1rem;
  color: var(--text);
  margin-bottom: 4px;
}
.page-about .team-entry p {
  margin: 0;
  font-size: 15px;
  line-height: 1.65;
  color: var(--text-dim);
}

/* ===== 技术实力 ===== */
.page-about .tech-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}
.page-about .tech-card {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 12px;
  padding: 26px 20px 20px;
  background: linear-gradient(150deg, rgba(26, 58, 110, 0.8), rgba(11, 29, 58, 0.25));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform 0.2s ease, border-color 0.2s;
}
.page-about .tech-card:hover {
  transform: translateY(-2px);
  border-color: rgba(166, 77, 244, 0.45);
}
.page-about .tech-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, var(--accent), var(--purple));
  transform: scaleX(0);
  transform-origin: 0 0;
  transition: transform 0.35s ease;
}
.page-about .tech-card:hover::before {
  transform: scaleX(1);
}
.page-about .tech-card-num {
  font-family: var(--font-body);
  font-weight: 800;
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--text-faint);
}
.page-about .tech-card h3 {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 1.2rem;
  color: var(--accent);
}
.page-about .tech-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-dim);
}
.page-about .tech-card .tech-card-link {
  margin-top: auto;
}
.page-about .tech-metrics {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin-top: 24px;
  padding: 16px;
  background: rgba(16, 24, 40, 0.4);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.page-about .metric-item {
  display: flex;
  flex-direction: column-reverse;
  gap: 4px;
  padding: 10px 12px;
  border-left: 3px solid var(--accent);
  background: rgba(11, 29, 58, 0.3);
}
.page-about .metric-num {
  font-family: var(--font-body);
  font-weight: 800;
  font-size: 1.6rem;
  line-height: 1.1;
  color: var(--text);
}
.page-about .metric-label {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-faint);
}

/* ===== 通用图片容器 ===== */
.page-about .story-figure {
  margin: 24px 0 0;
}
.page-about .story-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.page-about .story-figure figcaption {
  margin-top: 10px;
  padding-left: 12px;
  border-left: 3px solid var(--purple);
  font-size: 13px;
  color: var(--text-faint);
}

/* ===== 服务承诺 ===== */
.page-about .promise-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}
.page-about .promise-card {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 14px;
  padding: 26px 22px;
  background: linear-gradient(155deg, rgba(26, 58, 110, 0.7), rgba(11, 29, 58, 0.25));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: transform 0.2s ease, border-color 0.2s ease;
}
.page-about .promise-card:hover {
  transform: translateY(-2px);
  border-color: rgba(166, 77, 244, 0.5);
}
.page-about .promise-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: 999px;
  background: rgba(166, 77, 244, 0.16);
  border: 1px solid rgba(166, 77, 244, 0.4);
  color: var(--purple);
  font-size: 16px;
  font-weight: 800;
}
.page-about .promise-card h3 {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 1.15rem;
  color: var(--text);
}
.page-about .promise-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-dim);
}
.page-about .promise-card .btn {
  margin-top: 4px;
}
.page-about .trust-note {
  margin-top: 28px;
  padding: 20px 22px;
  border: 1px solid rgba(255, 106, 0, 0.3);
  background: rgba(255, 106, 0, 0.08);
  border-radius: var(--radius);
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-dim);
}
.page-about .trust-note p {
  margin: 0;
}
.page-about .trust-note a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 700;
}
.page-about .trust-note a:hover,
.page-about .trust-note a:focus-visible {
  text-decoration: underline;
}

/* ===== 桌面端布局 ===== */
@media (min-width: 700px) {
  .page-about .tech-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
  }
  .page-about .tech-metrics {
    grid-template-columns: repeat(4, 1fr);
    padding: 20px;
  }
  .page-about .metric-item {
    padding: 14px;
  }
  .page-about .metric-num {
    font-size: 1.8rem;
  }
  .page-about .promise-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
  }
}

@media (min-width: 900px) {
  .page-about .story-layout {
    padding: 96px 0 120px;
  }
  .page-about .story-layout-inner {
    grid-template-columns: var(--story-rail-w) minmax(0, 1fr);
    gap: 56px;
    align-items: start;
  }
  .page-about .story-rail {
    position: sticky;
    top: calc(var(--header-h) + 28px);
    border: 0;
    background: transparent;
    padding: 0;
  }
  .page-about .rail-nav {
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    overflow: visible;
  }
  .page-about .rail-link {
    white-space: normal;
    padding: 10px 12px;
  }
  .page-about .rail-link.is-active {
    background: rgba(255, 106, 0, 0.12);
    border-color: rgba(255, 106, 0, 0.35);
    color: var(--text);
  }
  .page-about .rail-footer {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-top: 24px;
    padding-top: 14px;
    border-top: 1px solid var(--border);
    font-size: 11px;
    color: var(--text-faint);
    letter-spacing: 0.1em;
  }
  .page-about .story-hero-window {
    min-height: 640px;
  }
  .page-about .story-hero-content {
    padding: 56px 64px 48px;
  }
  .page-about .hero-stats {
    grid-template-columns: repeat(4, 1fr);
    margin-top: 48px;
  }
  .page-about .milestone-timeline {
    gap: 28px;
    padding-left: 12px;
  }
  .page-about .milestone-timeline::before {
    left: 31px;
  }
  .page-about .milestone-item {
    grid-template-columns: 64px minmax(0, 1fr);
    gap: 24px;
  }
  .page-about .milestone-marker {
    gap: 12px;
  }
  .page-about .milestone-panel {
    padding: 22px 24px;
  }
  .page-about .milestone-panel h3 {
    font-size: 1.25rem;
  }
  .page-about .team-grid {
    grid-template-columns: 1.05fr 0.95fr;
    gap: 56px;
    align-items: center;
  }
  .page-about .team-item {
    padding: 20px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition: none !important;
    animation: none !important;
    transform: none !important;
  }
}