.page-about {
  --about-super: clamp(7rem, 22vw, 20rem);
  background-color: var(--bg-deep);
  color: var(--text-main);
  overflow-x: hidden;
}
.page-about .section-head {
  margin-bottom: var(--space-4);
}

/* ===== 英雄区 ===== */
.about-hero {
  position: relative;
  padding: clamp(28px, 5vw, 64px) 0 56px;
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(135deg, rgba(0, 229, 255, 0.06), transparent 42%),
    radial-gradient(circle at 82% 18%, rgba(57, 255, 20, 0.08), transparent 48%),
    var(--bg-deep);
}
.about-hero::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, var(--neon-green), var(--electric-blue));
}
.about-hero-grid-bg {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(rgba(58, 71, 80, 0.22) 1px, transparent 1px),
    linear-gradient(90deg, rgba(58, 71, 80, 0.22) 1px, transparent 1px);
  background-size: 56px 56px;
  pointer-events: none;
}
.about-hero-inner {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  align-items: center;
}
.about-hero-yearcol {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 20px 16px;
  border: 2px solid var(--line);
  background: linear-gradient(160deg, rgba(26, 33, 44, 0.55), rgba(13, 15, 20, 0.9));
  position: relative;
}
.about-hero-yearcol::after {
  content: "";
  position: absolute;
  inset: 6px;
  border: 1px solid var(--line-strong);
  pointer-events: none;
}
.about-hero-year {
  font-family: var(--font-display);
  font-size: var(--about-super);
  line-height: 0.88;
  color: rgba(57, 255, 20, 0.16);
  -webkit-text-stroke: 1px rgba(57, 255, 20, 0.5);
  letter-spacing: -0.02em;
  white-space: nowrap;
}
.about-hero-year-sub {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.3em;
  color: var(--text-dim);
  margin-top: 4px;
}
.about-hero-main {
  padding: 0 2px;
}
.about-hero-kicker {
  margin-bottom: 16px;
}
.about-hero-title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.1rem, 6vw, 4rem);
  line-height: 1.06;
  margin: 0 0 20px;
  color: var(--text-main);
  letter-spacing: 0.01em;
}
.about-hero-title em {
  font-style: normal;
  display: block;
  font-size: 0.5em;
  line-height: 1.3;
  color: var(--text-main);
  border-left: 4px solid var(--neon-green);
  padding-left: 16px;
  margin-top: 10px;
  font-family: var(--font-mono);
  font-weight: 400;
  letter-spacing: 0.02em;
}
.about-hero-desc {
  font-family: var(--font-mono);
  font-size: 0.92rem;
  line-height: 1.75;
  color: var(--text-dim);
  max-width: 60ch;
  margin: 0 0 28px;
}
.about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-bottom: 32px;
}
.about-hero-facts {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 16px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.about-hero-fact-num {
  font-family: var(--font-accent);
  font-size: 1.7rem;
  color: var(--neon-green);
  line-height: 1;
}
.about-hero-fact-label {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-dim);
  letter-spacing: 0.08em;
}
.about-hero-fact-sep {
  color: var(--line-strong);
  font-size: 1.2rem;
  margin: 0 4px;
}

/* ===== 品牌简介 ===== */
.about-intro {
  padding: clamp(48px, 8vw, 88px) 0;
  background: var(--bg-deep);
}
.about-intro-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
}
.about-intro-aside {
  display: none;
}
.about-vertical {
  writing-mode: vertical-rl;
  transform: rotate(180deg);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.32em;
  color: var(--text-dim);
  border-left: 1px solid var(--line);
  padding-left: 12px;
  height: 240px;
  white-space: nowrap;
}
.about-intro-copy {
  font-family: var(--font-mono);
  font-size: 0.92rem;
  line-height: 1.78;
  color: var(--text-dim);
  margin-bottom: 32px;
}
.about-intro-copy p {
  margin: 0 0 16px;
}
.about-intro-copy p:last-child {
  margin-bottom: 0;
}
.about-intro-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  margin-bottom: 28px;
}
.about-stat {
  background: var(--bg-card);
  border: 1px solid var(--line);
  padding: 18px 12px;
  text-align: center;
  position: relative;
  transition: border-color 160ms ease;
}
.about-stat:hover {
  border-color: var(--electric-blue);
}
.about-stat-num {
  display: block;
  font-family: var(--font-accent);
  font-size: 2rem;
  color: var(--neon-green);
  line-height: 1.1;
}
.about-stat-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--text-dim);
  margin-top: 6px;
  letter-spacing: 0.04em;
}
.about-intro-link {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.86rem;
  color: var(--text-dim);
  text-decoration: none;
  border-bottom: 1px dashed var(--line-strong);
  padding-bottom: 3px;
  transition: color 160ms ease, border-color 160ms ease;
}
.about-intro-link:hover {
  color: var(--neon-green);
  border-color: var(--neon-green);
}

/* ===== 发展里程碑 ===== */
.about-milestones {
  position: relative;
  padding: clamp(48px, 8vw, 88px) 0;
  background: var(--bg-panel);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.about-milestones-lead {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--text-dim);
  max-width: 72ch;
  margin: 0 0 40px;
}
.about-milestones-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
  align-items: start;
}
.about-milestones-media {
  position: relative;
  border: 1px solid var(--line-strong);
  background: var(--bg-card);
  padding: 12px;
  box-shadow: 8px 8px 0 rgba(0, 0, 0, 0.35);
  transform: rotate(-1deg);
}
.about-milestones-img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}
.about-milestones-media-note {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.22em;
  color: var(--text-dim);
  padding: 12px 2px 2px;
}
.about-timeline {
  position: relative;
}
.about-timeline-item {
  position: relative;
  border-left: 2px solid var(--line);
  padding-left: 20px;
  padding-bottom: 4px;
  margin-bottom: 4px;
}
.about-timeline-item[open] {
  border-left-color: var(--neon-green);
  padding-bottom: 14px;
}
.about-timeline-head {
  list-style: none;
  cursor: pointer;
  display: grid;
  grid-template-columns: 64px 1fr auto;
  align-items: center;
  gap: 12px;
  padding: 8px 0;
  user-select: none;
}
.about-timeline-head::-webkit-details-marker {
  display: none;
}
.about-timeline-dot {
  position: absolute;
  left: -5px;
  top: 14px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  border: 2px solid var(--electric-blue);
  background: var(--bg-panel);
}
.about-timeline-item[open] .about-timeline-dot {
  background: var(--neon-green);
  border-color: var(--neon-green);
  box-shadow: 0 0 12px rgba(57, 255, 20, 0.5);
}
.about-timeline-year {
  font-family: var(--font-accent);
  font-size: 0.95rem;
  color: var(--electric-blue);
  letter-spacing: 0.06em;
}
.about-timeline-item[open] .about-timeline-year {
  color: var(--neon-green);
}
.about-timeline-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
  color: var(--text-main);
  line-height: 1.3;
}
.about-timeline-arrow {
  font-family: var(--font-mono);
  color: var(--text-dim);
  font-size: 1.1rem;
  transition: transform 160ms ease;
}
.about-timeline-item[open] .about-timeline-arrow {
  transform: rotate(45deg);
  color: var(--neon-green);
}
.about-timeline-body {
  font-family: var(--font-mono);
  font-size: 0.87rem;
  line-height: 1.65;
  color: var(--text-dim);
  margin-top: 4px;
}
.about-timeline-body p {
  margin: 0;
}

/* ===== 数据版本演进 ===== */
.about-versions {
  position: relative;
  padding: clamp(56px, 9vw, 100px) 0;
  overflow: hidden;
  background: var(--bg-deep);
}
.about-versions-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  opacity: 0.22;
}
.about-versions-bg-img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.about-versions-super {
  position: absolute;
  right: -2vw;
  top: 32px;
  z-index: 0;
  font-family: var(--font-display);
  font-size: clamp(5rem, 16vw, 14rem);
  line-height: 1;
  color: rgba(0, 229, 255, 0.12);
  -webkit-text-stroke: 1px rgba(0, 229, 255, 0.25);
  pointer-events: none;
}
.about-versions .container {
  position: relative;
  z-index: 1;
}
.about-versions-lead {
  font-family: var(--font-mono);
  font-size: 0.92rem;
  line-height: 1.78;
  color: var(--text-dim);
  max-width: 68ch;
  margin: 0 0 40px;
  border-left: 3px solid var(--electric-blue);
  padding-left: 18px;
}
.about-versions-rotate {
  position: absolute;
  right: 10px;
  bottom: 48px;
  writing-mode: vertical-rl;
  transform: rotate(180deg);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.3em;
  color: var(--text-dim);
  opacity: 0.7;
  z-index: 1;
}
.about-version-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
}
.about-version-card {
  position: relative;
  background: linear-gradient(160deg, var(--bg-elevated), var(--bg-card));
  border: 1px solid var(--line);
  padding: 32px 24px 20px;
  box-shadow: 6px 6px 0 rgba(0, 0, 0, 0.25);
  transition: border-color 160ms ease, box-shadow 160ms ease, transform 160ms ease;
}
.about-version-card::before {
  content: "";
  position: absolute;
  inset: 6px;
  border: 1px solid var(--line);
  pointer-events: none;
}
.about-version-card:hover {
  border-color: var(--electric-blue);
  box-shadow: 6px 6px 0 rgba(0, 229, 255, 0.12);
  transform: translate(-2px, -2px);
}
.about-version-code {
  display: inline-block;
  font-family: var(--font-accent);
  font-size: 0.82rem;
  letter-spacing: 0.14em;
  color: var(--neon-green);
  border: 1px solid var(--line-strong);
  padding: 4px 10px;
  margin-bottom: 16px;
  background: rgba(57, 255, 20, 0.06);
}
.about-version-card h3 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.15rem;
  color: var(--text-main);
  margin: 0 0 8px;
}
.about-version-card p {
  font-family: var(--font-mono);
  font-size: 0.86rem;
  line-height: 1.65;
  color: var(--text-dim);
  margin: 0;
  min-height: 72px;
}
.about-version-year {
  display: inline-block;
  margin-top: 18px;
  font-family: var(--font-accent);
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  color: var(--electric-blue);
  border-top: 1px solid var(--line);
  padding-top: 8px;
}
.about-versions-more {
  display: inline-block;
  margin-top: 32px;
  font-family: var(--font-mono);
  font-size: 0.88rem;
  color: var(--electric-blue);
  text-decoration: none;
  border-bottom: 1px solid var(--electric-blue);
  padding-bottom: 3px;
  transition: color 160ms ease, border-color 160ms ease;
}
.about-versions-more:hover {
  color: var(--neon-green);
  border-color: var(--neon-green);
}

/* ===== 服务理念 ===== */
.about-principles {
  padding: clamp(48px, 8vw, 88px) 0;
  background: var(--bg-panel);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.about-principles-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
  align-items: center;
}
.about-principles-media {
  position: relative;
  border: 2px solid var(--line);
  padding: 12px;
  background: var(--bg-card);
}
.about-principles-media::after {
  content: "";
  position: absolute;
  top: 8px;
  right: 8px;
  width: 18px;
  height: 18px;
  border-top: 2px solid var(--neon-green);
  border-right: 2px solid var(--neon-green);
}
.about-principles-img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}
.about-principles-media-note {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.22em;
  color: var(--text-dim);
  padding: 12px 2px 2px;
  text-align: right;
}
.about-principle {
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 16px;
  padding: 20px 0;
  border-bottom: 1px solid var(--line);
}
.about-principle:last-child {
  border-bottom: 0;
}
.about-principle-num {
  font-family: var(--font-accent);
  font-size: 0.92rem;
  color: var(--neon-green);
  border: 1px solid var(--line-strong);
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.about-principle-body h3 {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 900;
  margin: 0 0 6px;
  color: var(--text-main);
}
.about-principle-body p {
  font-family: var(--font-mono);
  font-size: 0.88rem;
  line-height: 1.7;
  color: var(--text-dim);
  margin: 0;
}

/* ===== 资质与认证 ===== */
.about-certifications {
  padding: clamp(48px, 8vw, 88px) 0;
  background: var(--bg-deep);
}
.about-cert-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
  margin-bottom: 40px;
}
.about-cert-card {
  position: relative;
  background: var(--bg-panel);
  border: 1px solid var(--line);
  padding: 28px 24px;
  transition: border-color 160ms ease;
}
.about-cert-card:hover {
  border-color: var(--electric-blue);
}
.about-cert-card::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--electric-blue), var(--neon-green));
  opacity: 0.6;
}
.about-cert-code {
  display: inline-block;
  font-family: var(--font-accent);
  font-size: 0.74rem;
  letter-spacing: 0.2em;
  color: var(--signal-orange);
  border: 1px solid var(--line-strong);
  padding: 3px 8px;
  margin-bottom: 16px;
}
.about-cert-card h3 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.02rem;
  color: var(--text-main);
  margin: 0 0 10px;
}
.about-cert-card p {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  line-height: 1.6;
  color: var(--text-dim);
  margin: 0;
}
.about-cert-bar {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  padding: 32px;
  border: 1px solid var(--line-strong);
  background:
    linear-gradient(135deg, rgba(57, 255, 20, 0.07), transparent 40%),
    linear-gradient(315deg, rgba(0, 229, 255, 0.06), transparent 50%),
    var(--bg-panel);
}
.about-cert-bar::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, var(--neon-green), var(--electric-blue), var(--neon-green));
}
.about-cert-bar-meta {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px 24px;
}
.about-cert-bar-label {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.12em;
  color: var(--text-dim);
}
.about-cert-bar-value {
  font-family: var(--font-accent);
  font-size: 1.2rem;
  color: var(--text-main);
  text-align: right;
}
.about-cert-bar-text {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--text-dim);
  margin: 0;
}
.about-cert-bar-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

/* ===== 响应式断点 ===== */
@media (min-width: 640px) {
  .about-intro-stats {
    grid-template-columns: repeat(4, 1fr);
  }
  .about-version-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .about-cert-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .about-timeline-body {
    padding-left: 76px;
  }
  .about-versions-rotate {
    right: 24px;
  }
}

@media (min-width: 960px) {
  .about-hero {
    padding-bottom: 72px;
  }
  .about-hero-inner {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
    gap: 56px;
  }
  .about-hero-yearcol {
    align-self: stretch;
    min-height: 420px;
  }
  .about-intro-layout {
    grid-template-columns: 140px 1fr;
    gap: 56px;
  }
  .about-intro-aside {
    display: flex;
    justify-content: flex-start;
    padding-top: 12px;
  }
  .about-milestones-grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    gap: 56px;
  }
  .about-milestones-media {
    transform: rotate(-1deg);
  }
  .about-principles-layout {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
    gap: 64px;
  }
  .about-cert-grid {
    grid-template-columns: repeat(4, 1fr);
  }
  .about-cert-bar {
    grid-template-columns: 220px 1fr auto;
    align-items: center;
    gap: 32px;
  }
  .about-cert-bar-meta {
    grid-template-columns: 1fr;
    gap: 4px;
  }
  .about-cert-bar-value {
    text-align: left;
  }
}

@media (min-width: 1200px) {
  .about-version-grid {
    grid-template-columns: repeat(4, 1fr);
  }
  .about-principles-media {
    padding: 16px;
  }
}