.page-about {
  --about-rule: 1px solid var(--grey-300);
  --about-dark-rule: 1px solid rgba(246, 247, 243, 0.18);
  padding: 0;
  background: var(--paper);
  color: var(--ink);
  overflow-x: clip;
}

.page-about .about-band {
  width: 100%;
  max-width: var(--shell-max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.page-about .about-h1 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 36px;
  line-height: 1.04;
  font-weight: 700;
  letter-spacing: -0.008em;
  color: var(--ink);
}

.page-about .about-h2 {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-size: 27px;
  line-height: 1.14;
  font-weight: 700;
  letter-spacing: -0.005em;
}

.page-about .about-p {
  margin: 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--grey-900);
  max-width: 60ch;
}

/* ---------- 顶部上下文 ---------- */
.page-about .about-topbar {
  padding-top: clamp(16px, 3vw, 30px);
}

.page-about .about-topbar .breadcrumb {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.05em;
  color: var(--grey-900);
}

.page-about .about-topbar .breadcrumb a {
  color: var(--green);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s var(--ease);
}

.page-about .about-topbar .breadcrumb a:hover,
.page-about .about-topbar .breadcrumb a:focus-visible {
  border-bottom-color: var(--green);
}

/* ---------- 首屏 ---------- */
.page-about .about-mast {
  padding-block: clamp(24px, 4vw, 44px) clamp(36px, 6vw, 72px);
}

.page-about .about-mast-inner {
  display: grid;
  gap: clamp(18px, 3vw, 28px);
}

.page-about .about-mast-eyebrow {
  display: grid;
  gap: 10px;
  border-left: 3px solid var(--cyan);
  padding-left: 14px;
}

.page-about .about-mast-note {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--grey-900);
  max-width: 34ch;
}

.page-about .about-lead {
  margin: 0;
  font-size: 16px;
  line-height: 1.85;
  color: var(--grey-900);
  max-width: 62ch;
}

.page-about .about-quick-index {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--grey-300);
  border: var(--about-rule);
}

.page-about .about-quick-item {
  background: var(--paper);
  padding: 14px 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 5px;
  min-height: 44px;
}

.page-about .about-quick-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--green);
}

.page-about .about-quick-value {
  font-family: var(--font-display);
  font-size: 26px;
  font-weight: 600;
  line-height: 1;
  color: var(--ink);
}

.page-about .about-quick-note {
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--grey-900);
}

.page-about .about-mast-figure {
  margin: 0;
  border: var(--about-rule);
  background: var(--fog);
  overflow: hidden;
  aspect-ratio: 16 / 9;
  box-shadow: 6px 6px 0 rgba(44, 56, 52, 0.08);
}

.page-about .about-mast-figure img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  background: var(--green);
  color: var(--paper);
  padding-block: clamp(40px, 6vw, 84px);
}

.page-about .about-timeline .about-h2,
.page-about .about-timeline .about-node-heading {
  color: var(--paper);
}

.page-about .about-timeline .about-p {
  color: rgba(246, 247, 243, 0.76);
}

.page-about .about-timeline-intro {
  margin-bottom: clamp(26px, 4vw, 44px);
}

.page-about .about-timeline-grid {
  display: grid;
  gap: clamp(22px, 3vw, 40px);
}

.page-about .about-rail-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--mist);
  margin-bottom: 12px;
}

.page-about .about-rail-list {
  list-style: none;
  margin: 0;
  padding: 0 0 10px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-rail-list li {
  flex: 0 0 auto;
}

.page-about .about-rail-list a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 44px;
  padding: 10px 12px;
  border: 1px solid rgba(246, 247, 243, 0.26);
  color: var(--mist);
  font-size: 13px;
  line-height: 1.4;
  text-decoration: none;
  transition: background 0.2s var(--ease), border-color 0.2s var(--ease), color 0.2s var(--ease);
}

.page-about .about-rail-list a .num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--cyan);
}

.page-about .about-rail-list a:hover,
.page-about .about-rail-list a:focus-visible {
  background: rgba(39, 230, 200, 0.14);
  border-color: var(--cyan);
  color: var(--paper);
}

.page-about .about-rail-list a:focus-visible {
  outline: 2px solid var(--lime);
  outline-offset: 2px;
}

.page-about .about-timeline-nodes {
  display: grid;
}

.page-about .about-node {
  border-top: var(--about-dark-rule);
  scroll-margin-top: 96px;
}

.page-about .about-node:last-child {
  border-bottom: var(--about-dark-rule);
}

.page-about .about-node summary {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 20px 34px 20px 0;
  position: relative;
  cursor: pointer;
  list-style: none;
  min-height: 44px;
}

.page-about .about-node summary::-webkit-details-marker {
  display: none;
}

.page-about .about-node summary::after {
  content: "+";
  position: absolute;
  right: 0;
  top: 16px;
  font-family: var(--font-mono);
  font-size: 20px;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-node[open] summary::after {
  content: "\2013";
}

.page-about .about-node summary:hover .about-node-heading,
.page-about .about-node summary:focus-visible .about-node-heading {
  color: var(--cyan);
}

.page-about .about-node summary:focus-visible {
  outline: 2px solid var(--lime);
  outline-offset: 2px;
}

.page-about .about-node-year {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--cyan);
}

.page-about .about-node-heading {
  font-family: var(--font-display);
  font-size: 17px;
  line-height: 1.4;
  font-weight: 600;
  color: var(--paper);
  transition: color 0.2s var(--ease);
}

.page-about .about-node-body {
  padding-bottom: 22px;
}

.page-about .about-node-body p {
  margin: 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(246, 247, 243, 0.76);
}

/* ---------- 内容方法 ---------- */
.page-about .about-craft {
  padding-block: clamp(44px, 6vw, 88px);
}

.page-about .about-craft-grid {
  display: grid;
  gap: clamp(24px, 4vw, 44px);
}

.page-about .about-craft-figure {
  margin: 0;
  border: var(--about-rule);
  background: var(--fog);
  overflow: hidden;
  aspect-ratio: 3 / 2;
  box-shadow: 6px 6px 0 rgba(12, 59, 46, 0.1);
}

.page-about .about-craft-figure img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
}

.page-about .about-craft-main .kicker {
  display: inline-block;
  margin-bottom: 10px;
  color: var(--green);
}

.page-about .about-craft-list {
  display: grid;
  gap: 18px;
  margin-top: 26px;
}

.page-about .about-craft-list article {
  border-left: 3px solid var(--cyan);
  padding-left: 15px;
}

.page-about .about-craft-list h3 {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--ink);
}

.page-about .about-craft-list p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--grey-900);
}

.page-about .about-craft-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: 28px;
  background: var(--grey-300);
  border: var(--about-rule);
}

.page-about .about-craft-stats > div {
  background: var(--paper);
  padding: 16px 14px;
}

.page-about .about-craft-stats .num {
  display: block;
  font-family: var(--font-mono);
  font-size: 28px;
  font-weight: 600;
  line-height: 1;
  color: var(--green);
}

.page-about .about-craft-stats p {
  margin: 8px 0 0;
  font-size: 12.5px;
  line-height: 1.65;
  color: var(--grey-900);
}

/* ---------- 工作节奏 ---------- */
.page-about .about-rhythm {
  background: linear-gradient(180deg, var(--paper) 0%, var(--fog) 100%);
  padding-block: clamp(44px, 6vw, 84px);
}

.page-about .about-rhythm-head {
  margin-bottom: clamp(24px, 4vw, 36px);
}

.page-about .about-rhythm-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--grey-300);
  border: var(--about-rule);
}

.page-about .about-rhythm-steps li {
  background: var(--paper);
  padding: 20px 16px 22px;
}

.page-about .about-step-num {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--green);
}

.page-about .about-rhythm-steps h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 600;
  color: var(--ink);
}

.page-about .about-rhythm-steps p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--grey-900);
}

/* ---------- 合作生态 ---------- */
.page-about .about-partners {
  background: var(--ink);
  color: var(--paper);
  padding-block: clamp(44px, 6vw, 88px);
}

.page-about .about-partners .about-h2 {
  color: var(--paper);
}

.page-about .about-partners .about-p {
  color: rgba(246, 247, 243, 0.76);
}

.page-about .about-partners-head {
  margin-bottom: clamp(26px, 4vw, 44px);
}

.page-about .about-partners-head .kicker {
  display: inline-block;
  margin-bottom: 10px;
  color: var(--cyan);
}

.page-about .about-partners-grid {
  display: grid;
  gap: clamp(24px, 4vw, 44px);
}

.page-about .about-badge-wall {
  margin: 0;
  border: 1px solid rgba(246, 247, 243, 0.22);
  background: rgba(39, 230, 200, 0.06);
  overflow: hidden;
  aspect-ratio: 3 / 2;
}

.page-about .about-badge-wall img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
}

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

.page-about .about-partner-list li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  padding-top: 18px;
  border-top: var(--about-dark-rule);
}

.page-about .about-partner-list .num {
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 600;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-partner-list h3 {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 600;
  color: var(--paper);
}

.page-about .about-partner-list p {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: rgba(246, 247, 243, 0.72);
}

/* ---------- 安全与认证 ---------- */
.page-about .about-security {
  padding-block: clamp(44px, 6vw, 84px);
}

.page-about .about-cert-grid {
  display: grid;
  gap: 16px;
  margin-top: clamp(24px, 4vw, 34px);
}

.page-about .about-cert {
  border: var(--about-rule);
  background: var(--paper);
  padding: 20px 18px;
  box-shadow: 4px 4px 0 rgba(44, 56, 52, 0.08);
  transition: transform 0.2s var(--ease), box-shadow 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-cert:hover,
.page-about .about-cert:focus-within {
  transform: translateY(-2px);
  border-color: var(--green);
  box-shadow: 6px 8px 0 rgba(12, 59, 46, 0.14);
}

.page-about .about-cert h3 {
  margin: 12px 0 8px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 600;
  color: var(--ink);
}

.page-about .about-cert > p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--grey-900);
}

.page-about .about-cert-scope {
  margin: 12px 0 0;
  padding-top: 12px;
  border-top: 1px dashed var(--grey-300);
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.7;
  color: var(--grey-900);
  opacity: 0.62;
  transition: opacity 0.2s var(--ease);
}

.page-about .about-cert:hover .about-cert-scope,
.page-about .about-cert:focus-within .about-cert-scope {
  opacity: 1;
}

.page-about .about-security-link {
  margin: 26px 0 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--grey-900);
}

.page-about .about-security-link a,
.page-about .about-cta-foot a {
  color: var(--green);
  font-weight: 600;
  text-decoration: none;
  border-bottom: 1px solid var(--green);
}

.page-about .about-security-link a:hover,
.page-about .about-security-link a:focus-visible,
.page-about .about-cta-foot a:hover,
.page-about .about-cta-foot a:focus-visible {
  color: var(--ink);
  border-bottom-color: var(--orange);
}

/* ---------- 收束 ---------- */
.page-about .about-cta {
  padding-block: clamp(40px, 6vw, 80px) clamp(48px, 7vw, 96px);
}

.page-about .about-cta .about-band {
  border-top: 3px solid var(--orange);
  padding-top: clamp(26px, 4vw, 40px);
}

.page-about .about-cta .about-h2 {
  font-size: 28px;
  max-width: 20ch;
}

.page-about .about-cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

.page-about .about-cta-foot {
  margin: 22px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--grey-900);
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .about-h1 {
    font-size: 46px;
  }

  .page-about .about-quick-index {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-quick-item {
    padding: 16px 16px 18px;
  }

  .page-about .about-rhythm-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-cert-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-h1 {
    font-size: clamp(48px, 5.2vw, 68px);
    max-width: 18ch;
  }

  .page-about .about-h2 {
    font-size: 32px;
  }

  .page-about .about-mast-inner {
    grid-template-columns: 210px minmax(0, 1fr);
    grid-template-areas:
      "eyebrow title"
      "eyebrow lead"
      "index   index"
      "figure  figure";
    gap: clamp(20px, 2.6vw, 34px) clamp(24px, 3vw, 44px);
    align-items: start;
  }

  .page-about .about-mast-eyebrow {
    grid-area: eyebrow;
    padding-top: 8px;
  }

  .page-about .about-h1 {
    grid-area: title;
  }

  .page-about .about-lead {
    grid-area: lead;
  }

  .page-about .about-quick-index {
    grid-area: index;
  }

  .page-about .about-mast-figure {
    grid-area: figure;
  }

  .page-about .about-timeline-grid {
    grid-template-columns: 200px minmax(0, 1fr);
    gap: clamp(28px, 4vw, 56px);
  }

  .page-about .about-rail-list {
    flex-direction: column;
    overflow: visible;
    padding-bottom: 0;
    gap: 0;
  }

  .page-about .about-rail-list li {
    border-top: 1px solid rgba(246, 247, 243, 0.16);
  }

  .page-about .about-rail-list li:last-child {
    border-bottom: 1px solid rgba(246, 247, 243, 0.16);
  }

  .page-about .about-rail-list a {
    width: 100%;
    border: 0;
    padding: 14px 0;
    justify-content: flex-start;
  }

  .page-about .about-node-heading {
    font-size: 21px;
  }

  .page-about .about-craft-grid {
    grid-template-columns: minmax(0, 0.78fr) minmax(0, 1.22fr);
    align-items: start;
  }

  .page-about .about-partners-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: center;
  }
}

@media (min-width: 1080px) {
  .page-about .about-rhythm-steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-cert-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-cta .about-h2 {
    font-size: 40px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-cert,
  .page-about .about-cert-scope,
  .page-about .about-node-heading,
  .page-about .about-rail-list a,
  .page-about .about-topbar .breadcrumb a {
    transition: none;
  }

  .page-about .about-cert:hover,
  .page-about .about-cert:focus-within {
    transform: none;
  }
}
<<<END>>>