.page-about {
  --about-radius: 20px;
  overflow-x: hidden;
  font-family: var(--font-body);
  color: var(--c-text);
  background: var(--c-surface);
}

/* ===== 通用内页标题 ===== */
.page-about .section-label {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 20px;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--c-primary);
}
.page-about .section-label::before {
  content: "";
  width: 30px;
  height: 3px;
  border-radius: 99px;
  background: var(--grad-primary);
}
.page-about .section-title {
  margin: 0 0 16px;
  max-width: 16em;
  font-family: var(--font-display);
  font-size: clamp(28px, 6vw, 46px);
  font-weight: 900;
  line-height: 1.12;
  color: inherit;
}
.page-about .btn-primary {
  border: none;
}

/* ===== 动态渐入（JS 不可用时内容保持可见）===== */
.js .page-about [data-reveal] {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}
.js .page-about [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ===== 首屏 ===== */
.page-about .about-hero {
  position: relative;
  padding: 72px 0;
  overflow: hidden;
  background: var(--c-bg-dark);
  color: var(--c-on-dark);
}
.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: 0;
  right: -10%;
  width: 72%;
  height: 100%;
  opacity: 0.16;
  background: var(--grad-primary);
  clip-path: polygon(18% 0, 100% 0, 100% 100%, 0 100%);
  transform: skewX(-7deg);
}
.page-about .about-hero::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, var(--c-primary), var(--c-accent) 60%, transparent);
}
.page-about .about-hero .breadcrumb {
  position: relative;
  z-index: 2;
  margin-bottom: 28px;
  color: var(--c-on-dark-muted);
}
.page-about .about-hero .breadcrumb a {
  color: var(--c-on-dark);
}
.page-about .about-hero .breadcrumb .breadcrumb-sep {
  color: var(--c-on-dark-muted);
}
.page-about .about-hero-inner {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
}
.page-about .about-hero-left {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}
.page-about .about-hero .section-label {
  color: var(--c-on-dark-muted);
}
.page-about .about-hero .section-label::before {
  background: var(--grad-primary);
}
.page-about .about-hero h1 {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-size: clamp(36px, 8vw, 72px);
  font-weight: 900;
  line-height: 1;
  text-transform: uppercase;
  color: var(--c-on-dark);
  transform: skewX(-2deg);
}
@supports (background-clip: text) or (-webkit-background-clip: text) {
  .page-about .about-hero h1 {
    background: linear-gradient(100deg, var(--c-on-dark) 20%, var(--c-primary-soft) 70%, var(--c-primary));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
  }
}
.page-about .about-hero-lead {
  margin: 0 0 24px;
  font-size: clamp(18px, 3.5vw, 28px);
  font-weight: 700;
  color: var(--c-accent);
}
.page-about .about-hero-text {
  max-width: 30em;
  margin: 0 0 36px;
  color: var(--c-on-dark-muted);
  line-height: 1.8;
}
.page-about .about-hero-metrics {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  width: 100%;
  max-width: 520px;
  margin-bottom: 32px;
}
.page-about .about-hero-metric {
  padding: 14px 8px;
  text-align: center;
  border-radius: 12px;
  border-top: 2px solid var(--c-primary);
  background: rgba(255, 255, 255, 0.05);
}
.page-about .about-hero-metric:nth-child(2) {
  border-top-color: var(--c-accent);
}
.page-about .about-hero-metric:nth-child(3) {
  border-top-color: var(--c-data);
}
.page-about .about-hero-metric .metric-value {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(20px, 4vw, 30px);
  font-weight: 700;
  color: var(--c-on-dark);
}
.page-about .about-hero-metric .metric-label {
  display: block;
  margin-top: 4px;
  font-size: 12px;
  color: var(--c-on-dark-muted);
}
.page-about .about-hero-anchors {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  margin-top: 8px;
}
.page-about .about-hero-anchors a {
  font-size: 14px;
  color: var(--c-on-dark-muted);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: color var(--trans), border-color var(--trans);
}
.page-about .about-hero-anchors a:hover,
.page-about .about-hero-anchors a:focus {
  color: var(--c-on-dark);
  border-bottom-color: var(--c-primary);
}
.page-about .about-hero-visual {
  display: none;
}
.page-about .about-hero-svg {
  width: 100%;
  max-width: 360px;
  height: auto;
}
.page-about .about-hero-path {
  animation: aboutHeroDash 1.6s linear infinite;
}
@keyframes aboutHeroDash {
  to {
    stroke-dashoffset: -32;
  }
}

/* ===== 我们的起点 ===== */
.page-about .about-origin {
  position: relative;
  padding: 72px 0;
  background: var(--c-surface);
}
.page-about .about-origin::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 40%;
  height: 40%;
  clip-path: polygon(0 0, 100% 0, 0 100%);
  background: rgba(255, 59, 47, 0.05);
}
.page-about .about-origin-grid {
  position: relative;
  display: grid;
  gap: 32px;
}
.page-about .about-origin-copy h2 {
  margin: 0 0 16px;
  font-family: var(--font-display);
  font-size: clamp(26px, 5vw, 38px);
  font-weight: 900;
  line-height: 1.2;
}
.page-about .about-origin-lead {
  margin-bottom: 16px;
  font-size: 18px;
  font-weight: 700;
  color: var(--c-primary);
}
.page-about .about-origin-copy p {
  margin-bottom: 16px;
  color: var(--c-text);
  line-height: 1.75;
}
.page-about .about-origin-copy .btn {
  margin-top: 16px;
}
.page-about .about-origin-cards {
  display: grid;
  gap: 16px;
}
.page-about .about-origin-card {
  padding: 24px;
  border: 1px solid var(--c-border);
  border-top: 4px solid var(--c-primary);
  border-radius: var(--about-radius);
  background: var(--c-surface);
  box-shadow: var(--shadow-sm);
  transform: skewX(-1deg);
}
.page-about .about-origin-card:nth-child(2) {
  border-top-color: var(--c-primary-soft);
}
.page-about .about-origin-card:nth-child(3) {
  border-top-color: var(--c-accent);
}
.page-about .about-origin-card-num {
  font-family: var(--font-mono);
  font-size: 42px;
  font-weight: 700;
  line-height: 1;
  color: var(--c-primary);
}
.page-about .about-origin-card-title {
  margin: 8px 0;
  font-size: 18px;
  font-weight: 700;
  color: var(--c-secondary);
}
.page-about .about-origin-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--c-text-light);
}

/* ===== 技术演进 ===== */
.page-about .about-tech {
  position: relative;
  padding: 72px 0;
  overflow: hidden;
  background: var(--c-bg-dark);
  color: var(--c-on-dark);
}
.page-about .about-tech::before {
  content: "";
  position: absolute;
  top: 0;
  left: -10%;
  width: 120%;
  height: 10px;
  background: linear-gradient(90deg, transparent, rgba(0, 212, 255, 0.45), transparent);
  transform: rotate(1.5deg);
}
.page-about .about-tech .section-title,
.page-about .about-tech .section-label {
  color: var(--c-on-dark);
}
.page-about .about-tech .section-label::before {
  background: var(--grad-primary);
}
.page-about .about-tech-lead {
  margin-bottom: 36px;
  color: var(--c-on-dark-muted);
}
.page-about .about-tech-stage-list {
  display: grid;
  gap: 20px;
  margin-bottom: 48px;
}
.page-about .about-tech-stage {
  position: relative;
  padding: 28px;
  overflow: hidden;
  border-radius: 16px;
  border-left: 4px solid var(--c-primary);
  background: rgba(255, 255, 255, 0.04);
}
.page-about .about-tech-stage:nth-child(2) {
  border-left-color: var(--c-primary-soft);
}
.page-about .about-tech-stage:nth-child(3) {
  border-left-color: var(--c-accent);
}
.page-about .about-tech-stage-tag {
  display: inline-block;
  margin-bottom: 12px;
  padding: 4px 14px;
  border-radius: 99px;
  background: var(--grad-primary);
  color: var(--c-on-dark);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  transform: skewX(-8deg);
}
.page-about .about-tech-stage h3 {
  margin: 0 0 10px;
  font-size: 20px;
  font-weight: 800;
  color: var(--c-on-dark);
}
.page-about .about-tech-stage p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--c-on-dark-muted);
}
.page-about .about-tech-media {
  display: grid;
  gap: 24px;
}
.page-about .about-tech-figure {
  margin: 0;
}
.page-about .about-tech-figure img {
  width: 100%;
  max-width: 500px;
  height: auto;
  aspect-ratio: 10 / 7;
  object-fit: cover;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 16px;
}
.page-about .about-tech-figure figcaption {
  margin-top: 8px;
  font-size: 13px;
  color: var(--c-on-dark-muted);
}

/* ===== 里程亮点 ===== */
.page-about .about-milestones {
  position: relative;
  padding: 72px 0;
  background: var(--c-surface);
}
.page-about .about-milestones .section-title {
  color: var(--c-secondary);
}
.page-about .about-milestones-lead {
  margin-bottom: 40px;
  color: var(--c-text-light);
}
.page-about .about-milestones-grid {
  display: grid;
  gap: 48px;
}
.page-about .about-timeline {
  position: relative;
  margin: 0;
  padding: 0;
  list-style: none;
}
.page-about .about-timeline::before {
  content: "";
  position: absolute;
  top: 8px;
  bottom: 8px;
  left: 9px;
  width: 3px;
  border-radius: 99px;
  opacity: 0.7;
  background: linear-gradient(180deg, var(--c-primary), var(--c-accent), var(--c-primary-soft));
}
.page-about .about-timeline-item {
  position: relative;
  padding-left: 44px;
  padding-bottom: 40px;
}
.page-about .about-timeline-item:last-child {
  padding-bottom: 0;
}
.page-about .about-timeline-dot {
  position: absolute;
  top: 6px;
  left: 0;
  width: 21px;
  height: 21px;
  border: 6px solid var(--c-primary);
  border-radius: 50%;
  background: var(--c-surface);
  box-shadow: 0 0 0 4px rgba(255, 59, 47, 0.18);
}
.page-about .about-timeline-card {
  padding: 24px;
  border: 1px solid var(--c-border);
  border-left: 4px solid var(--c-primary);
  border-radius: var(--about-radius);
  background: var(--c-surface);
  transition: box-shadow var(--trans), transform var(--trans);
}
.page-about .about-timeline-card:hover,
.page-about .about-timeline-card:focus-within {
  box-shadow: var(--shadow-md);
  transform: translateX(2px);
}
.page-about .about-timeline-time {
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--c-primary);
}
.page-about .about-timeline-card h3 {
  margin: 0 0 8px;
  font-size: 20px;
  font-weight: 800;
  color: var(--c-secondary);
}
.page-about .about-timeline-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-text-light);
}
.page-about .about-milestones-figure {
  margin: 0;
}
.page-about .about-milestones-figure img {
  width: 100%;
  max-width: 600px;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  border-radius: var(--about-radius);
  box-shadow: var(--shadow-md);
  transform: rotate(1.5deg);
}
.page-about .about-milestones-figure figcaption {
  margin-top: 12px;
  font-size: 13px;
  color: var(--c-text-light);
}

/* ===== 团队与理念 ===== */
.page-about .about-team {
  position: relative;
  padding: 72px 0;
  overflow: hidden;
  background: var(--c-bg-dark);
  color: var(--c-on-dark);
}
.page-about .about-team::after {
  content: "";
  position: absolute;
  right: -80px;
  bottom: -80px;
  width: 320px;
  height: 320px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255, 59, 47, 0.18), transparent 70%);
}
.page-about .about-team .section-label {
  color: var(--c-on-dark);
}
.page-about .about-team .section-label::before {
  background: var(--grad-primary);
}
.page-about .about-team .section-title {
  color: var(--c-on-dark);
}
.page-about .about-team-grid {
  position: relative;
  z-index: 2;
  display: grid;
  gap: 40px;
}
.page-about .about-team-copy > p {
  margin-bottom: 24px;
  color: var(--c-on-dark-muted);
  line-height: 1.75;
}
.page-about .about-team-points {
  display: grid;
  gap: 16px;
  margin-bottom: 24px;
}
.page-about .about-team-point {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 20px;
  border-left: 4px solid var(--c-accent);
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.05);
}
.page-about .about-team-point:nth-child(2) {
  border-left-color: var(--c-primary);
}
.page-about .about-team-point:nth-child(3) {
  border-left-color: var(--c-data);
}
.page-about .about-team-point-num {
  flex-shrink: 0;
  font-family: var(--font-mono);
  font-size: 28px;
  font-weight: 700;
  line-height: 1;
  color: var(--c-primary);
}
.page-about .about-team-point-text h3 {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 800;
  color: var(--c-on-dark);
}
.page-about .about-team-point-text p {
  margin: 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--c-on-dark-muted);
}
.page-about .about-team-figure {
  margin: 0;
}
.page-about .about-team-figure img {
  width: 100%;
  max-width: 400px;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--about-radius);
  clip-path: polygon(6% 0, 100% 0, 94% 100%, 0 100%);
}
.page-about .about-team-figure figcaption {
  margin-top: 12px;
  font-size: 13px;
  color: var(--c-on-dark-muted);
}

/* ===== 折叠面板 ===== */
.page-about .about-details {
  margin-top: 24px;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.04);
}
.page-about .about-details[open] {
  border-color: rgba(0, 212, 255, 0.4);
}
.page-about .about-details summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 16px 20px;
  cursor: pointer;
  list-style: none;
  font-size: 15px;
  font-weight: 700;
  color: var(--c-on-dark);
}
.page-about .about-details summary::-webkit-details-marker {
  display: none;
}
.page-about .about-details summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 22px;
  line-height: 1;
  color: var(--c-accent);
  transition: transform var(--trans);
}
.page-about .about-details[open] summary::after {
  content: "\2212";
  transform: rotate(90deg);
}
.page-about .about-details-body {
  padding: 0 20px 20px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-on-dark-muted);
}
.page-about .about-details-body p {
  margin: 0 0 12px;
}
.page-about .about-details-body .btn {
  margin-top: 4px;
}

/* ===== 尾部 CTA ===== */
.page-about .about-cta {
  position: relative;
  padding: 80px 0;
  overflow: hidden;
  text-align: center;
  background: var(--grad-primary);
}
.page-about .about-cta::before {
  content: "";
  position: absolute;
  top: -8px;
  left: -30%;
  width: 160%;
  height: 16px;
  background: rgba(255, 255, 255, 0.18);
  transform: rotate(-2deg);
}
.page-about .about-cta-inner {
  position: relative;
  z-index: 2;
}
.page-about .about-cta h2 {
  margin: 0 0 16px;
  font-family: var(--font-display);
  font-size: clamp(26px, 6vw, 42px);
  font-weight: 900;
  color: #fff;
  text-shadow: 0 4px 24px rgba(0, 0, 0, 0.18);
}
.page-about .about-cta p {
  max-width: 40em;
  margin: 0 auto 28px;
  font-size: 16px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.92);
}
.page-about .about-cta-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 16px;
}
.page-about .about-cta .btn-primary {
  border: none;
  background: var(--c-secondary);
  color: #fff;
}
.page-about .about-cta .btn-ghost {
  border: 1px solid rgba(255, 255, 255, 0.6);
  background: transparent;
  color: #fff;
}
.page-about .about-cta .btn-ghost:hover,
.page-about .about-cta .btn-ghost:focus {
  background: rgba(255, 255, 255, 0.14);
}

/* ===== 动效偏好：减少动态 ===== */
@media (prefers-reduced-motion: reduce) {
  .js .page-about [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }
  .page-about .about-hero-path {
    animation: none;
  }
  .page-about .about-timeline-card:hover,
  .page-about .about-timeline-card:focus-within {
    transform: none;
  }
}

/* ===== 桌面端布局 ===== */
@media (min-width: 768px) {
  .page-about .about-origin-card {
    padding: 28px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 104px 0 96px;
  }
  .page-about .about-hero-inner {
    grid-template-columns: 7fr 5fr;
    align-items: center;
    gap: 48px;
  }
  .page-about .about-hero-visual {
    display: block;
  }
  .page-about .about-origin {
    padding: 96px 0;
  }
  .page-about .about-origin-grid {
    grid-template-columns: 1fr 1fr;
    align-items: center;
    gap: 64px;
  }
  .page-about .about-origin-cards {
    grid-template-columns: 1fr;
    gap: 24px;
  }
  .page-about .about-tech {
    padding: 104px 0;
  }
  .page-about .about-tech-stage-list {
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
  }
  .page-about .about-tech-media {
    grid-template-columns: 5fr 7fr;
    align-items: center;
    gap: 48px;
  }
  .page-about .about-milestones {
    padding: 96px 0;
  }
  .page-about .about-milestones-grid {
    grid-template-columns: 3fr 2fr;
    align-items: start;
    gap: 72px;
  }
  .page-about .about-timeline-card {
    padding: 28px;
  }
  .page-about .about-team {
    padding: 96px 0;
  }
  .page-about .about-team-grid {
    grid-template-columns: 1.1fr 0.9fr;
    align-items: center;
    gap: 64px;
  }
  .page-about .about-cta {
    padding: 96px 0;
  }
}