.page-about{
  --chapter-pad: clamp(64px, 10vw, 120px);
  --aside-w: 280px;
  color: var(--ink-hi);
  background: var(--bg-void);
  font-family: var(--font-body);
  overflow-x: hidden;
}

/* 面包屑 */
.page-about .breadcrumb{
  margin: 28px 0 0;
  font-size: 13px;
  color: var(--ink-mid);
}
.page-about .breadcrumb a{
  color: var(--ink-mid);
  text-decoration: none;
  transition: color .2s;
}
.page-about .breadcrumb a:hover,
.page-about .breadcrumb a:focus-visible{
  color: var(--accent);
}
.page-about .bc-sep{
  margin: 0 10px;
  color: var(--ink-low);
}

/* 首屏 */
.page-about .about-hero{
  position: relative;
  padding: 48px 0 72px;
  border-bottom: 1px solid var(--line);
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 48px 48px;
}
.page-about .about-hero::after{
  content: "EST. 2014 / CN";
  position: absolute;
  top: 22px;
  right: 24px;
  font-family: var(--font-data);
  font-size: 11px;
  letter-spacing: .2em;
  color: var(--ink-low);
}
.page-about .about-hero-grid{
  display: grid;
  gap: 44px;
  margin-top: 48px;
}
.page-about .about-hero-copy{
  position: relative;
  padding-top: 26px;
}
.page-about .about-hero-copy::before{
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 72px;
  height: 3px;
  background: linear-gradient(90deg, var(--fire-start), var(--fire-end), var(--accent));
  border-radius: 2px;
}
.page-about .hero-kicker{
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-data);
  font-size: 12px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 20px;
}
.page-about .kicker-dot{
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 14px var(--accent);
  animation: about-pulse 2s infinite;
}
@keyframes about-pulse{
  0%, 100%{ opacity: 1; }
  50%{ opacity: .4; }
}
.page-about .about-hero-copy h1{
  font-family: var(--font-h);
  font-size: clamp(32px, 5.2vw, 54px);
  line-height: 1.15;
  margin: 0 0 22px;
  font-weight: 900;
  letter-spacing: -.02em;
  max-width: 720px;
}
.page-about .h1-divider{
  color: var(--accent);
  font-weight: 300;
  margin: 0 8px;
}
.page-about .hero-lead{
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink-mid);
  max-width: 640px;
  margin: 0 0 30px;
}
.page-about .hero-actions{
  display: flex;
  flex-wrap: wrap;
  gap: 12px 24px;
  margin-bottom: 36px;
}
.page-about .hero-quick-link{
  color: var(--ink-hi);
  font-size: 14px;
  text-decoration: none;
  border-bottom: 1px solid var(--line);
  padding-bottom: 2px;
  transition: color .2s, border-color .2s;
}
.page-about .hero-quick-link:hover,
.page-about .hero-quick-link:focus-visible{
  color: var(--accent);
  border-color: var(--accent);
}
.page-about .hero-meta{
  display: flex;
  flex-wrap: wrap;
  gap: 28px 36px;
}
.page-about .hero-stat{
  display: flex;
  flex-direction: column;
}
.page-about .hero-stat-num{
  font-family: var(--font-data);
  font-size: 30px;
  font-weight: 700;
  color: var(--ink-hi);
  letter-spacing: -.02em;
}
.page-about .hero-stat-label{
  color: var(--ink-low);
  font-size: 12px;
  margin-top: 4px;
  letter-spacing: .04em;
}

/* 首屏右侧索引 */
.page-about .about-hero-index{
  position: relative;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--bg-panel);
  padding: 22px 20px;
}
.page-about .about-hero-index::before,
.page-about .about-hero-index::after{
  content: "";
  position: absolute;
  width: 14px;
  height: 14px;
  border-color: var(--accent);
  border-style: solid;
  opacity: .8;
}
.page-about .about-hero-index::before{
  top: -1px;
  left: -1px;
  border-width: 2px 0 0 2px;
}
.page-about .about-hero-index::after{
  bottom: -1px;
  right: -1px;
  border-width: 0 2px 2px 0;
}
.page-about .index-frame-label{
  font-family: var(--font-data);
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--ink-low);
  margin: 0 0 18px;
  border-bottom: 1px solid var(--line);
  padding-bottom: 12px;
}
.page-about .index-list{
  list-style: none;
  margin: 0;
  padding: 0;
}
.page-about .index-list li + li{
  border-top: 1px solid var(--line);
}
.page-about .index-list a{
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 4px;
  color: var(--ink-mid);
  font-size: 14px;
  text-decoration: none;
  transition: color .2s, padding-left .2s;
}
.page-about .index-list a::after{
  content: "→";
  margin-left: auto;
  color: var(--ink-low);
  transition: color .2s, transform .2s;
}
.page-about .index-list a:hover,
.page-about .index-list a:focus-visible{
  color: var(--accent);
  padding-left: 10px;
}
.page-about .index-list a:hover::after,
.page-about .index-list a:focus-visible::after{
  transform: translateX(3px);
  color: var(--accent);
}
.page-about .idx-no{
  font-family: var(--font-data);
  font-size: 12px;
  color: var(--ink-low);
}

/* 章节通用 */
.page-about .about-chapter{
  padding: var(--chapter-pad) 0;
  border-bottom: 1px solid var(--line);
  position: relative;
  scroll-margin-top: calc(var(--header-h) + 16px);
}
.page-about .about-chapter::before{
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--accent) 0%, transparent 65%);
  opacity: .45;
}
.page-about .chapter-grid{
  display: grid;
  gap: 32px;
}
.page-about .chapter-aside{
  display: grid;
  gap: 6px;
}
.page-about .chapter-num{
  font-family: var(--font-data);
  font-size: 64px;
  line-height: .9;
  color: transparent;
  -webkit-text-stroke: 1px var(--line);
  font-weight: 700;
  user-select: none;
}
.page-about .chapter-aside h2{
  font-family: var(--font-h);
  font-size: 28px;
  line-height: 1.2;
  margin: 10px 0 0;
  font-weight: 800;
  letter-spacing: -.01em;
}
.page-about .chapter-sub{
  font-family: var(--font-data);
  font-size: 11px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--accent);
}
.page-about .chapter-main{
  min-width: 0;
}
.page-about .chapter-main p{
  color: var(--ink-mid);
  font-size: 15px;
  line-height: 1.9;
  max-width: 680px;
}
.page-about .chapter-lead{
  font-size: 18px;
  line-height: 1.75;
  color: var(--ink-hi) !important;
  margin: 0 0 18px;
  font-weight: 600;
}

/* 01 初心与使命 */
.page-about .origin-principles{
  display: grid;
  gap: 14px;
  margin: 28px 0 10px;
}
.page-about .principle-item{
  border: 1px solid var(--line);
  border-radius: 0 var(--radius) var(--radius) 0;
  border-left: 3px solid var(--accent);
  background: var(--bg-panel);
  padding: 18px 20px;
}
.page-about .principle-item h3{
  font-size: 15px;
  color: var(--ink-hi);
  margin: 6px 0 6px;
  font-weight: 700;
}
.page-about .principle-item p{
  font-size: 14px;
  line-height: 1.7;
  margin: 0;
  color: var(--ink-mid) !important;
}
.page-about .p-number{
  font-family: var(--font-data);
  font-size: 12px;
  color: var(--accent);
  letter-spacing: .08em;
}
.page-about .origin-note{
  margin-top: 20px;
  padding: 16px 18px;
  background: var(--accent-soft);
  border-radius: var(--radius);
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-hi);
}
.page-about .origin-note a{
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color .2s;
}
.page-about .origin-note a:hover,
.page-about .origin-note a:focus-visible{
  border-bottom-color: var(--accent);
}

/* 02 发展里程碑 */
.page-about .milestone-logo-img{
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  margin-bottom: 36px;
}
.page-about .timeline{
  position: relative;
  padding-left: 34px;
}
.page-about .timeline::before{
  content: "";
  position: absolute;
  left: 17px;
  top: 14px;
  bottom: 18px;
  width: 2px;
  transform: translateX(-50%);
  background: linear-gradient(to bottom, var(--accent) 0%, var(--line) 32%, var(--line) 78%, transparent 100%);
}
.page-about .tl-item{
  position: relative;
  border-bottom: 1px solid var(--line);
}
.page-about .tl-item:last-of-type{
  border-bottom: none;
}
.page-about .tl-item::before{
  content: "";
  position: absolute;
  left: -23px;
  top: 30px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--bg-void);
  border: 2px solid var(--accent);
  box-shadow: 0 0 0 4px var(--accent-soft), 0 0 16px rgba(57, 255, 20, .2);
  transition: transform .2s ease, box-shadow .2s ease;
}
.page-about .tl-item:hover::before,
.page-about .tl-item:focus-within::before{
  transform: scale(1.15);
  box-shadow: 0 0 0 6px var(--accent-soft), 0 0 24px rgba(57, 255, 20, .35);
}
.page-about .tl-item summary{
  list-style: none;
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 22px 0;
  cursor: pointer;
  position: relative;
}
.page-about .tl-item summary::-webkit-details-marker{
  display: none;
}
.page-about .tl-item summary:focus-visible{
  outline: 2px solid var(--accent);
  outline-offset: 4px;
}
.page-about .tl-year{
  font-family: var(--font-data);
  font-size: 24px;
  font-weight: 700;
  color: var(--accent);
  min-width: 72px;
  letter-spacing: -.02em;
  transition: color .2s;
}
.page-about .tl-title{
  color: var(--ink-hi);
  font-size: 15px;
  font-weight: 600;
  line-height: 1.4;
}
.page-about .tl-arrow{
  margin-left: auto;
  color: var(--ink-low);
  font-family: var(--font-data);
  font-size: 20px;
  line-height: 1;
  transition: transform .3s, color .3s;
}
.page-about .tl-item[open] .tl-arrow{
  transform: rotate(45deg);
  color: var(--accent);
}
.page-about .tl-body{
  color: var(--ink-mid);
  font-size: 14px;
  line-height: 1.85;
  max-width: 620px;
  padding: 0 0 22px 86px;
}
.page-about .tl-body p{
  font-size: 14px;
  line-height: 1.85;
  color: var(--ink-mid) !important;
}
.page-about .inline-link{
  display: inline-block;
  margin-top: 20px;
  color: var(--accent);
  text-decoration: none;
  font-family: var(--font-data);
  font-size: 13px;
  letter-spacing: .04em;
  border-bottom: 1px solid rgba(57, 255, 20, .35);
  padding-bottom: 3px;
  transition: border-color .2s, color .2s;
}
.page-about .inline-link:hover,
.page-about .inline-link:focus-visible{
  border-bottom-color: var(--accent);
}

/* 03 技术与团队 */
.page-about .team-layout{
  display: grid;
  gap: 32px;
}
.page-about .team-numbers{
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 12px;
  margin: 28px 0 24px;
}
.page-about .team-num-card{
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--bg-panel);
  padding: 18px 14px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.page-about .team-num{
  font-family: var(--font-data);
  font-size: 30px;
  font-weight: 700;
  color: var(--accent);
  line-height: 1;
}
.page-about .team-num-label{
  font-size: 13px;
  color: var(--ink-mid);
}
.page-about .team-img{
  width: 100%;
  height: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  display: block;
}

/* 04 资质与认证 */
.page-about .cert-grid{
  display: grid;
  gap: 18px;
  margin-top: 24px;
}
.page-about .cert-item{
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--bg-panel);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.page-about .cert-item img{
  width: 120px;
  height: 120px;
  object-fit: cover;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}
.page-about .cert-item h3{
  font-size: 17px;
  margin: 0;
  color: var(--ink-hi);
  font-weight: 700;
  line-height: 1.4;
}
.page-about .cert-item p{
  font-size: 14px;
  line-height: 1.75;
  margin: 0;
  color: var(--ink-mid) !important;
}
.page-about .cert-icon-badge{
  width: 64px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-data);
  font-size: 14px;
  font-weight: 700;
  color: var(--accent);
  background: var(--accent-soft);
  border: 1px solid rgba(57, 255, 20, .3);
  border-radius: 50%;
}

/* 05 合作生态 */
.page-about .partner-grid{
  display: grid;
  gap: 16px;
  margin-top: 28px;
}
.page-about .partner-item{
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  background: var(--bg-panel);
  padding: 20px 22px;
  border-radius: 0 var(--radius) var(--radius) 0;
}
.page-about .partner-item h3{
  font-size: 15px;
  color: var(--accent);
  margin: 0 0 8px;
  font-family: var(--font-data);
  letter-spacing: .06em;
}
.page-about .partner-item p{
  font-size: 14px;
  color: var(--ink-mid) !important;
  margin: 0;
  line-height: 1.75;
  max-width: 100%;
}
.page-about .connect-cta{
  margin-top: 40px;
  padding: 22px 24px;
  border: 1px solid rgba(57, 255, 20, .25);
  background: var(--accent-soft);
  border-radius: var(--radius);
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-hi);
}
.page-about .connect-cta p{
  margin: 0;
  color: var(--ink-hi) !important;
}
.page-about .connect-cta a{
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color .2s;
}
.page-about .connect-cta a:hover,
.page-about .connect-cta a:focus-visible{
  border-bottom-color: var(--accent);
}

@media (min-width: 1080px){
  .page-about .about-hero-grid{
    grid-template-columns: 1fr 360px;
    align-items: start;
    gap: 64px;
    margin-top: 56px;
  }
  .page-about .about-hero{
    padding-bottom: 96px;
  }
  .page-about .chapter-grid{
    grid-template-columns: var(--aside-w) 1fr;
    gap: 64px;
  }
  .page-about .chapter-aside{
    position: sticky;
    top: calc(var(--header-h) + 24px);
    align-self: start;
  }
  .page-about .chapter-num{
    font-size: 92px;
  }
  .page-about .team-layout{
    grid-template-columns: 1fr 1fr;
    gap: 48px;
  }
  .page-about .cert-grid{
    grid-template-columns: repeat(3, 1fr);
  }
  .page-about .partner-grid{
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
  }
}