.page-about {
  --about-grid-line: rgba(255, 255, 255, 0.06);
  --about-muted: rgba(242, 244, 247, 0.7);
  background-color: var(--gray-light);
  color: var(--slate);
  font-family: var(--font-body);
  overflow-x: hidden;
}

/* ===== 首屏：品牌宣言 ===== */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  background: linear-gradient(135deg, var(--navy) 0%, var(--navy-2) 100%);
  color: var(--white);
  padding: 48px 0 56px;
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--about-grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--about-grid-line) 1px, transparent 1px);
  background-size: 32px 32px;
  z-index: -1;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -60px;
  top: -60px;
  width: 220px;
  height: 220px;
  background: linear-gradient(135deg, var(--gold) 0%, transparent 70%);
  border-radius: 32px;
  opacity: 0.1;
  transform: rotate(12deg);
  z-index: -1;
}

.page-about .breadcrumb {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  margin-bottom: 24px;
  color: var(--about-muted);
}

.page-about .breadcrumb a {
  color: var(--blue);
  text-decoration: none;
}

.page-about .breadcrumb .sep {
  margin: 0 8px;
}

.page-about .breadcrumb .current {
  color: rgba(255, 255, 255, 0.85);
}

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

.page-about .about-hero-kicker {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  letter-spacing: 0.14em;
  color: var(--gold);
  margin: 0 0 12px;
}

.page-about .about-hero h1 {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: clamp(1.75rem, 5vw, 2.75rem);
  line-height: 1.2;
  margin: 0 0 16px;
}

.page-about .about-hero-lead {
  font-size: 1rem;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.85);
  max-width: 560px;
}

.page-about .about-hero-meta {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--gold-soft);
  margin: 20px 0 0;
}

.page-about .about-hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
}

.page-about .about-hero-stat {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius);
  padding: 18px 12px;
  transition: var(--transition);
}

.page-about .about-hero-stat:hover {
  border-color: var(--gold-soft);
}

.page-about .about-hero-stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.375rem;
  font-weight: 700;
  line-height: 1.2;
  color: var(--gold);
  margin-bottom: 6px;
}

.page-about .about-hero-stat-label {
  font-size: 0.75rem;
  color: rgba(255, 255, 255, 0.7);
}

/* ===== 品牌使命 ===== */
.page-about .about-mission {
  background: var(--white);
  padding: 56px 0;
}

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

.page-about .about-eyebrow {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  color: var(--blue);
  margin: 0 0 8px;
}

.page-about .about-mission h2,
.page-about .about-data-head h2,
.page-about .about-journey-head h2,
.page-about .about-team h2 {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.625rem;
  line-height: 1.25;
  margin: 0 0 16px;
  color: var(--navy);
}

.page-about .about-mission-copy p {
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--slate);
  margin: 0 0 14px;
}

.page-about .about-mission-copy a {
  color: var(--blue);
  text-decoration: none;
  box-shadow: inset 0 -1px 0 rgba(0, 208, 255, 0.4);
}

.page-about .about-mission-copy a:hover {
  box-shadow: inset 0 -1px 0 var(--blue);
}

.page-about .about-mission-list {
  list-style: none;
  margin: 20px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .about-mission-list li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--slate);
}

.page-about .about-mission-list li::before {
  content: "";
  flex: 0 0 auto;
  width: 6px;
  height: 6px;
  margin-top: 9px;
  border-radius: 50%;
  background: var(--gold);
}

.page-about .about-mission-figure {
  margin: 0;
}

.page-about .about-mission-figure img,
.page-about .about-team-figure img {
  width: 100%;
  height: auto;
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
}

.page-about .about-mission-figure figcaption,
.page-about .about-team-figure figcaption {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: #8994a3;
  margin-top: 8px;
}

/* ===== 数据版图 ===== */
.page-about .about-data {
  background: linear-gradient(180deg, var(--navy) 0%, var(--navy-2) 100%);
  color: var(--white);
  padding: 56px 0 64px;
}

.page-about .about-data-head {
  max-width: 620px;
  margin-bottom: 28px;
}

.page-about .about-data-head .about-eyebrow {
  color: var(--gold);
}

.page-about .about-data-head h2 {
  color: var(--white);
}

.page-about .about-data-head p:not(.about-eyebrow) {
  font-size: 0.9375rem;
  line-height: 1.7;
  color: var(--about-muted);
  margin: 0;
}

.page-about .about-data-grid {
  display: grid;
  gap: 14px;
}

.page-about .about-metric-card {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius);
  padding: 22px 20px;
  transition: var(--transition);
}

.page-about .about-metric-card:hover {
  border-color: var(--gold-soft);
  background: rgba(255, 255, 255, 0.08);
}

.page-about .about-metric-num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.75rem;
  line-height: 1.2;
  color: var(--gold);
  margin-bottom: 6px;
}

.page-about .about-metric-label {
  display: block;
  font-weight: 600;
  font-size: 0.875rem;
  color: var(--white);
  margin-bottom: 6px;
}

.page-about .about-metric-card p {
  font-size: 0.8125rem;
  line-height: 1.55;
  color: var(--about-muted);
  margin: 0;
}

.page-about .about-data-foot {
  margin-top: 24px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--about-muted);
}

.page-about .about-data-foot a {
  color: var(--blue);
  text-decoration: none;
}

/* ===== 发展历程 ===== */
.page-about .about-journey {
  background: var(--gray-light);
  padding: 56px 0;
}

.page-about .about-journey-head {
  max-width: 620px;
  margin-bottom: 28px;
}

.page-about .about-journey-head p:not(.about-eyebrow) {
  font-size: 0.9375rem;
  line-height: 1.7;
  color: var(--slate);
  opacity: 0.75;
  margin: 0;
}

.page-about .about-journey-figure {
  margin: 0 0 36px;
}

.page-about .about-journey-figure img {
  width: 100%;
  height: auto;
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
}

.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 0 0 0 48px;
  position: relative;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 15px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(180deg, var(--blue) 0%, var(--purple) 100%);
  opacity: 0.55;
}

.page-about .about-timeline-item {
  position: relative;
  margin-bottom: 24px;
}

.page-about .about-timeline-item:last-child {
  margin-bottom: 0;
}

.page-about .about-timeline-marker {
  position: absolute;
  left: 0;
  top: 4px;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: var(--navy);
  border: 2px solid var(--blue);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.625rem;
  font-weight: 700;
  color: var(--blue);
  z-index: 1;
}

.page-about .about-timeline-card {
  background: var(--white);
  border-radius: var(--radius);
  padding: 18px 18px 16px;
  box-shadow: var(--shadow-card);
  transition: var(--transition);
}

.page-about .about-timeline-card:hover {
  box-shadow: var(--shadow-lift);
  transform: translateY(-2px);
}

.page-about .about-timeline-card h3 {
  font-family: var(--font-heading);
  font-size: 1.0625rem;
  line-height: 1.3;
  margin: 0 0 6px;
  color: var(--navy);
}

.page-about .about-timeline-card p {
  font-size: 0.8125rem;
  line-height: 1.7;
  margin: 0;
  color: var(--slate);
}

.page-about .about-timeline-note {
  margin: 28px 0 0;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--slate);
  opacity: 0.75;
}

.page-about .about-timeline-note a {
  color: var(--blue);
  text-decoration: none;
}

/* ===== 团队与资质 ===== */
.page-about .about-team {
  background: var(--white);
  padding: 56px 0;
}

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

.page-about .about-team-copy p {
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--slate);
  margin: 0 0 14px;
}

.page-about .about-team-copy a {
  color: var(--blue);
  text-decoration: none;
  box-shadow: inset 0 -1px 0 rgba(0, 208, 255, 0.4);
}

.page-about .about-team-copy a:hover {
  box-shadow: inset 0 -1px 0 var(--blue);
}

.page-about .about-team-figure {
  margin: 0;
}

/* ===== 焦点状态 ===== */
.page-about a:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ===== 窄屏微调 ===== */
@media (max-width: 359px) {
  .page-about .about-hero-stats {
    grid-template-columns: 1fr;
  }
}

/* ===== 平板及以上 ===== */
@media (min-width: 768px) {
  .page-about .about-hero {
    padding: 72px 0 80px;
  }

  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 48px;
    align-items: end;
  }

  .page-about .about-mission,
  .page-about .about-journey,
  .page-about .about-team {
    padding: 72px 0;
  }

  .page-about .about-data {
    padding: 72px 0 80px;
  }

  .page-about .about-mission-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 48px;
    align-items: center;
  }

  .page-about .about-data-grid {
    grid-template-columns: repeat(4, 1fr);
    gap: 18px;
  }

  .page-about .about-team-grid {
    grid-template-columns: minmax(0, 6fr) minmax(0, 5fr);
    gap: 48px;
    align-items: center;
  }
}

/* ===== 桌面端时间轴 ===== */
@media (min-width: 900px) {
  .page-about .about-timeline {
    padding-left: 0;
  }

  .page-about .about-timeline::before {
    left: 50%;
    transform: translateX(-1px);
  }

  .page-about .about-timeline-item {
    width: 50%;
    margin-bottom: 28px;
    padding-right: 48px;
  }

  .page-about .about-timeline-item:nth-child(even) {
    margin-left: 50%;
    padding-left: 48px;
    padding-right: 0;
  }

  .page-about .about-timeline-marker {
    left: auto;
    right: -15px;
  }

  .page-about .about-timeline-item:nth-child(even) .about-timeline-marker {
    right: auto;
    left: -15px;
  }

  .page-about .about-timeline-card {
    text-align: right;
  }

  .page-about .about-timeline-item:nth-child(even) .about-timeline-card {
    text-align: left;
  }
}