.page-about {
  --about-tint: #E6F0EB;
  --about-line: rgba(10, 20, 26, 0.13);
  --about-muted: var(--rock-gray-deep);
  background: var(--ink-blue);
  color: var(--cream);
  font-family: var(--font-body);
  overflow-x: hidden;
}

.page-about .about-head {
  padding: 96px 0 0;
}

.page-about .about-head__strip {
  margin-top: 14px;
  font-size: 11px;
  letter-spacing: 0.06em;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  padding: 26px 0 48px;
}

.page-about .about-hero__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
}

.page-about .about-hero__copy {
  min-width: 0;
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: clamp(1.85rem, 6vw, 3.15rem);
  line-height: 1.18;
  letter-spacing: -0.02em;
  color: var(--cream);
}

.page-about .about-hero__lead {
  margin: 18px 0 0;
  max-width: 34em;
  font-size: 1rem;
  line-height: 1.85;
  color: rgba(244, 241, 233, 0.82);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.page-about .about-hero__media {
  margin: 0;
  min-width: 0;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--edge);
  background: var(--deep-rock);
}

.page-about .about-hero__media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-hero__media figcaption {
  padding: 10px 14px 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.7;
  letter-spacing: 0.02em;
  color: var(--rock-gray);
  border-top: 1px solid var(--edge-soft);
}

/* ---------- 主体分栏 ---------- */

.page-about .about-body {
  padding: 0 0 64px;
}

.page-about .about-body__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
}

.page-about .about-flow {
  min-width: 0;
}

/* ---------- 左侧索引轴 ---------- */

.page-about .about-axis__label {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.16em;
  color: var(--moss);
}

.page-about .about-axis__list {
  display: flex;
  gap: 6px;
  list-style: none;
  margin: 0;
  padding: 0 0 6px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-toc-link {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 9px 12px;
  border-left: 2px solid var(--edge);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: rgba(244, 241, 233, 0.03);
  text-decoration: none;
  white-space: nowrap;
  color: var(--rock-gray);
  transition: color var(--ease), border-color var(--ease), background var(--ease);
}

.page-about .about-toc-link__num {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--mountain-teal);
}

.page-about .about-toc-link__name {
  font-size: 13px;
}

.page-about .about-toc-link:hover,
.page-about .about-toc-link:focus-visible {
  border-left-color: var(--competition-orange);
  background: rgba(244, 241, 233, 0.08);
  color: var(--cream);
}

.page-about .about-toc-link.is-active {
  border-left-color: var(--competition-orange);
  background: rgba(31, 122, 107, 0.22);
  color: var(--cream);
}

/* ---------- 章节面板 ---------- */

.page-about .about-chapter {
  position: relative;
  margin-bottom: 20px;
  padding: 26px 20px 30px;
  border-left: 3px solid transparent;
  border-radius: var(--radius);
  background: var(--cream);
  color: var(--text-ink);
  transition: border-color var(--ease), background var(--ease);
}

.page-about .about-chapter:hover {
  border-left-color: var(--competition-orange);
}

.page-about .about-chapter--tint {
  background: var(--about-tint);
  --about-line: rgba(10, 20, 26, 0.16);
}

.page-about .about-chapter__head {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding-bottom: 14px;
  margin-bottom: 18px;
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-chapter__num {
  flex: none;
  font-family: var(--font-mono);
  font-size: 28px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--mountain-teal);
}

.page-about .about-chapter__kicker {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.10em;
  color: var(--about-muted);
}

.page-about .about-chapter h2 {
  margin: 0;
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: clamp(1.22rem, 3.4vw, 1.62rem);
  line-height: 1.28;
  letter-spacing: -0.02em;
  color: var(--text-ink);
}

.page-about .about-chapter__body {
  max-width: 36em;
  color: var(--text-ink);
}

.page-about .about-chapter__body p {
  margin: 0 0 1.1em;
  font-size: 0.95rem;
  line-height: 1.85;
}

.page-about .about-chapter__body p:last-child {
  margin-bottom: 0;
}

/* ---------- 四步工序 ---------- */

.page-about .about-method__figure {
  margin: 20px 0 22px;
  border-radius: var(--radius-sm);
  overflow: hidden;
  border: 1px solid var(--about-line);
  background: var(--cream);
}

.page-about .about-method__figure img {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .about-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
}

.page-about .about-step {
  padding: 16px 14px;
  border-radius: var(--radius-sm);
  background: rgba(31, 122, 107, 0.06);
  border-top: 2px solid transparent;
  transition: background var(--ease), border-color var(--ease);
}

.page-about .about-step:hover,
.page-about .about-step:focus-within {
  background: rgba(31, 122, 107, 0.13);
  border-top-color: var(--competition-orange);
}

.page-about .about-step__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--mountain-teal);
}

.page-about .about-step__title {
  margin: 6px 0 8px;
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.06rem;
  letter-spacing: -0.01em;
  color: var(--text-ink);
}

.page-about .about-step__text {
  margin: 0 0 8px;
  font-size: 0.88rem;
  line-height: 1.75;
  color: var(--text-ink);
}

.page-about .about-step__out {
  margin: 0 0 6px;
  font-size: 0.82rem;
  line-height: 1.65;
  color: var(--mountain-teal);
  font-weight: 700;
}

.page-about .about-step__risk {
  margin: 0;
  padding-top: 8px;
  border-top: 1px dashed var(--about-line);
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.7;
  color: var(--rock-gray-deep);
}

/* ---------- 版本时间线 ---------- */

.page-about .about-timeline {
  list-style: none;
  margin: 20px 0 0;
  padding: 0 0 0 4px;
  border-left: 2px solid var(--about-line);
}

.page-about .about-timeline__item {
  position: relative;
  padding: 0 0 20px 22px;
}

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

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -6px;
  top: 7px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--cream);
  border: 2px solid var(--mountain-teal);
}

.page-about .about-timeline__item--now::before {
  background: var(--competition-orange);
  border-color: var(--competition-orange);
  box-shadow: 0 0 0 4px rgba(242, 101, 34, 0.16);
}

.page-about .about-timeline__year {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.10em;
  color: var(--mountain-teal);
}

.page-about .about-timeline__item--now .about-timeline__year {
  color: var(--terracotta);
}

.page-about .about-timeline__body h3 {
  margin: 4px 0 6px;
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1rem;
  letter-spacing: -0.01em;
  color: var(--text-ink);
}

.page-about .about-timeline__body p {
  margin: 0;
  max-width: 34em;
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--text-ink);
}

/* ---------- 团队 ---------- */

.page-about .about-team {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}

.page-about .about-team__copy p {
  margin: 0 0 1em;
  font-size: 0.95rem;
  line-height: 1.85;
  color: var(--text-ink);
}

.page-about .about-team__copy p:last-child {
  margin-bottom: 0;
}

.page-about .about-team__figure {
  margin: 0;
  border-radius: var(--radius-sm);
  overflow: hidden;
  border: 1px solid var(--about-line);
  background: var(--cream);
}

.page-about .about-team__figure img {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .about-team__figure figcaption {
  padding: 10px 12px 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.7;
  color: var(--rock-gray-deep);
  border-top: 1px solid var(--about-line);
}

/* ---------- 配色 ---------- */

.page-about .about-palette {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.page-about .about-palette__item {
  padding: 10px;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-sm);
  background: rgba(244, 241, 233, 0.7);
}

.page-about .about-palette__swatch {
  display: block;
  height: 44px;
  border-radius: 2px;
  margin-bottom: 8px;
}

.page-about .about-palette__swatch--teal {
  background: var(--mountain-teal);
}

.page-about .about-palette__swatch--orange {
  background: var(--competition-orange);
}

.page-about .about-palette__swatch--ink {
  background: var(--ink-blue);
}

.page-about .about-palette__swatch--cream {
  background: var(--cream);
  border: 1px solid var(--about-line);
}

.page-about .about-palette__swatch--moss {
  background: var(--moss);
}

.page-about .about-palette__swatch--rock {
  background: var(--rock-gray);
}

.page-about .about-palette__name {
  display: block;
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 0.86rem;
  color: var(--text-ink);
}

.page-about .about-palette__use {
  display: block;
  margin-top: 2px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--rock-gray-deep);
}

/* ---------- 合作数据 ---------- */

.page-about .about-stats {
  margin-top: 22px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.page-about .about-stats__item {
  padding: 16px 14px;
  background: var(--cream);
}

.page-about .about-stats__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--mountain-teal);
}

.page-about .about-stats__label {
  display: block;
  margin-top: 4px;
  font-size: 12px;
  line-height: 1.6;
  color: var(--rock-gray-deep);
}

/* ---------- 结尾导航 ---------- */

.page-about .about-next {
  margin-top: 28px;
  padding: 26px 20px 28px;
  border: 1px solid var(--edge);
  border-radius: var(--radius);
  background: var(--deep-rock);
}

.page-about .about-next h2 {
  margin: 0 0 10px;
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: clamp(1.15rem, 3vw, 1.45rem);
  letter-spacing: -0.02em;
  color: var(--cream);
}

.page-about .about-next > p {
  margin: 0 0 18px;
  max-width: 34em;
  font-size: 0.92rem;
  line-height: 1.8;
  color: rgba(244, 241, 233, 0.76);
}

.page-about .about-next__links {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 8px;
}

.page-about .about-next__link {
  display: block;
  padding: 12px 14px;
  border: 1px solid var(--edge);
  border-left: 3px solid var(--moss);
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: border-color var(--ease), background var(--ease);
}

.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  border-left-color: var(--competition-orange);
  background: rgba(244, 241, 233, 0.05);
}

.page-about .about-next__link--accent {
  border-left-color: var(--competition-orange);
  background: rgba(242, 101, 34, 0.10);
}

.page-about .about-next__link-title {
  display: block;
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 0.94rem;
  color: var(--cream);
}

.page-about .about-next__link-desc {
  display: block;
  margin-top: 3px;
  font-size: 12px;
  line-height: 1.65;
  color: var(--rock-gray);
}

/* ---------- 响应式 ---------- */

@media (min-width: 640px) {
  .page-about .about-palette {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

@media (min-width: 760px) {
  .page-about .about-chapter {
    padding: 34px 32px 38px;
  }

  .page-about .about-chapter__num {
    font-size: 36px;
  }

  .page-about .about-chapter__body p,
  .page-about .about-team__copy p {
    font-size: 1rem;
  }

  .page-about .about-php,
  .page-about .about-php {
    display: none;
  }
}

@media (min-width: 860px) {
  .page-about .about-steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0;
    border-top: 2px solid var(--about-line);
  }

  .page-about .about-step {
    border-radius: 0;
    background: transparent;
    border-top: 0;
    padding: 16px 14px 12px;
  }

  .page-about .about-step + .about-step {
    border-left: 1px solid var(--about-line);
  }

  .page-about .about-step:hover,
  .page-about .about-step:focus-within {
    background: rgba(31, 122, 107, 0.10);
    border-top-color: transparent;
  }

  .page-about .about-team {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    gap: 28px;
    align-items: start;
  }
}

@media (min-width: 920px) {
  .page-about .about-hero {
    padding: 36px 0 60px;
  }

  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 6fr) minmax(0, 5fr);
    gap: 48px;
    align-items: center;
  }

  .page-about .about-body__grid {
    grid-template-columns: 172px minmax(0, 1fr);
    gap: 36px;
    align-items: start;
  }

  .page-about .about-axis {
    position: sticky;
    top: 92px;
  }

  .page-about .about-axis__list {
    display: grid;
    gap: 2px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-toc-link {
    padding: 10px 12px;
  }

  .page-about .about-next {
    padding: 32px 32px 34px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-toc-link,
  .page-about .about-chapter,
  .page-about .about-step,
  .page-about .about-next__link {
    transition: none;
  }
}
<<<END>>>