.page-about {
  --about-line: rgba(232, 241, 255, 0.14);
  --about-green: rgba(57, 255, 20, 0.18);
  --about-orange: rgba(255, 107, 53, 0.16);
  background: var(--c-bg);
  color: var(--c-text);
  overflow-x: hidden;
}

.page-about-breadcrumb {
  padding-top: 1.25rem;
}

.page-about-hero {
  padding-top: 1.5rem;
  padding-bottom: 3.5rem;
}

.page-about-hero-copy h1 {
  font-family: var(--font-head);
  font-size: clamp(2.1rem, 5.2vw, 4.3rem);
  line-height: 1.06;
  letter-spacing: -0.015em;
  margin: 1rem 0 1.5rem;
  border-left: 4px solid var(--c-accent);
  padding-left: 1rem;
}

.page-about-hero-copy .lede {
  color: var(--c-text-dim);
  font-size: 1.05rem;
  line-height: 1.8;
  max-width: 36em;
  margin: 0 0 1rem;
}

.page-about-hero-copy p {
  line-height: 1.75;
  margin: 0 0 1.4rem;
  max-width: 42em;
}

.page-about-hero-meta {
  margin: 1.75rem 0 1.25rem;
}

.page-about-hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
}

.page-about-hero-visual {
  position: relative;
  margin-top: 2.25rem;
  padding-left: 0.75rem;
}

.page-about-hero-visual::before {
  content: "CN官方入口 · 实时数据终端";
  position: absolute;
  z-index: 2;
  top: -0.75rem;
  left: 0;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.14em;
  color: var(--c-bg-deep);
  background: var(--c-accent);
  padding: 0.35rem 0.7rem;
  border-radius: 2px;
  box-shadow: 4px 4px 0 var(--c-cta);
}

.page-about-hero-visual img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--about-line);
  border-radius: var(--radius);
  box-shadow: 0 10px 0 var(--about-green), 0 20px 0 var(--about-orange), 0 28px 48px rgba(0, 0, 0, 0.4);
}

.page-about-milestones {
  padding-top: 2.5rem;
  padding-bottom: 3rem;
  background: linear-gradient(180deg, rgba(7, 18, 38, 0.95), rgba(11, 29, 58, 0.9)),
    repeating-linear-gradient(90deg, rgba(232, 241, 255, 0.03) 0 1px, transparent 1px 80px);
  border-top: 1px solid var(--about-line);
  border-bottom: 1px solid var(--about-line);
}

.page-about-section-head {
  margin-bottom: 1.5rem;
}

.page-about .section-title {
  font-family: var(--font-head);
  font-size: clamp(1.9rem, 3.6vw, 3rem);
  line-height: 1.1;
  margin-top: 0.8rem;
}

.page-about-milestone-bg {
  display: block;
  width: 100%;
  height: 210px;
  object-fit: cover;
  object-position: center;
  opacity: 0.6;
  border: 1px solid var(--about-line);
  border-radius: var(--radius);
  margin-top: 1.75rem;
}

.page-about-timeline {
  list-style: none;
  margin: 2.25rem 0 0;
  padding: 0;
}

.page-about-timeline-item {
  position: relative;
  padding: 0 0 2.25rem 1.25rem;
  border-left: 2px solid rgba(57, 255, 20, 0.35);
}

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

.page-about-timeline-item::before {
  content: "";
  position: absolute;
  top: 0.25rem;
  left: -0.5rem;
  width: 0.875rem;
  height: 0.875rem;
  border-radius: 50%;
  background: var(--c-bg);
  border: 3px solid var(--c-accent);
  box-shadow: 0 0 0 4px rgba(57, 255, 20, 0.12);
}

.page-about-timeline-item h3 {
  font-family: var(--font-head);
  font-size: 1.2rem;
  margin: 0.9rem 0 0.4rem;
  letter-spacing: 0.01em;
  font-weight: 900;
}

.page-about-timeline-item p {
  color: var(--c-text-dim);
  font-size: 0.92rem;
  line-height: 1.7;
  margin: 0;
}

.page-about-timeline-marker {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.6rem;
}

.page-about-timeline-time {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--c-cta-soft);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.page-about-tech {
  padding-top: 3.5rem;
  padding-bottom: 3.5rem;
}

.page-about-tech-copy .lede {
  color: var(--c-text);
  font-size: 1.05rem;
  line-height: 1.8;
  margin-top: 1.25rem;
}

.page-about-tech-copy p {
  color: var(--c-text-dim);
  line-height: 1.75;
  margin-bottom: 1rem;
}

.page-about-tech-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 2.25rem;
}

.page-about-tech-stat {
  background: var(--c-panel);
  border: 1px solid var(--about-line);
  border-radius: var(--radius);
  padding: 1.5rem 1.2rem;
  position: relative;
  min-height: 7.5rem;
  overflow: hidden;
}

.page-about-tech-stat::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: 0;
  width: 50%;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--c-accent));
}

.page-about-tech-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 2rem;
  font-weight: 700;
  line-height: 1.1;
  color: var(--c-accent);
}

.page-about-tech-label {
  display: block;
  margin-top: 0.6rem;
  color: var(--c-text-dim);
  font-size: 0.85rem;
  line-height: 1.4;
}

.page-about-tech-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.page-about-team {
  padding-top: 3.5rem;
  padding-bottom: 3.5rem;
  background: var(--c-bg-deep);
  border-top: 1px solid var(--about-line);
}

.page-about-credential-list {
  list-style: none;
  margin: 1.75rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.75rem;
}

.page-about-credential-list li {
  background: rgba(15, 42, 78, 0.55);
  border: 1px solid rgba(57, 255, 20, 0.18);
  border-left-width: 4px;
  border-left-color: var(--c-accent);
  border-radius: var(--radius);
  padding: 0.85rem 1rem 0.85rem 1.15rem;
  color: var(--c-text);
  font-size: 0.92rem;
  line-height: 1.5;
}

.page-about-team-visual {
  margin-top: 2rem;
}

.page-about-team-visual img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--about-line);
  border-radius: var(--radius);
  box-shadow: 0 20px 44px rgba(0, 0, 0, 0.35);
}

.page-about-team-note {
  border-left: 3px solid var(--c-cta);
  padding: 0.2rem 0 0.2rem 1rem;
  margin-top: 1.25rem;
  color: var(--c-text-dim);
  line-height: 1.7;
  font-size: 0.92rem;
}

.page-about-more {
  padding-top: 3rem;
  padding-bottom: 4rem;
}

.page-about-more-card {
  background: linear-gradient(135deg, rgba(57, 255, 20, 0.09), rgba(255, 107, 53, 0.07)),
    var(--c-panel);
  border: 1px solid var(--about-line);
  border-radius: var(--radius);
  padding: 2.5rem 1.5rem;
  text-align: center;
  position: relative;
  box-shadow: 0 18px 40px rgba(0, 0, 0, 0.25);
}

.page-about-more-card::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 25%;
  right: 25%;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--c-accent), var(--c-cta), transparent);
}

.page-about-more-card .lede {
  max-width: 30em;
  margin: 1rem auto 0;
  color: var(--c-text-dim);
  line-height: 1.7;
}

.page-about-more-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.75rem;
  margin-top: 1.75rem;
}

@media (min-width: 720px) {
  .page-about-hero-grid {
    display: grid;
    grid-template-columns: 1.05fr 0.95fr;
    gap: 2.5rem;
    align-items: center;
  }

  .page-about-hero-visual {
    margin-top: 0;
    padding-left: 0;
  }

  .page-about-milestone-bg {
    height: 280px;
  }

  .page-about-tech-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2.5rem;
    align-items: start;
  }

  .page-about-tech-stats {
    margin-top: 0;
  }

  .page-about-team-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2.5rem;
    align-items: start;
  }

  .page-about-team-visual {
    margin-top: 0;
  }
}

@media (min-width: 860px) {
  .page-about-hero {
    padding-top: 2.5rem;
    padding-bottom: 4.5rem;
  }

  .page-about-timeline {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem 3.5rem;
    margin-top: 2.5rem;
  }

  .page-about-timeline-item:nth-child(even) {
    margin-top: 3rem;
  }

  .page-about-more-card {
    padding: 3.5rem 3rem;
  }
}