.page-about {
  --ab-rail: 236px;
  --ab-line: rgba(143, 185, 174, 0.24);
  background: var(--ink-green);
  color: var(--paper);
  font-family: var(--font-body);
  overflow-x: clip;
}

.page-about h1,
.page-about h2,
.page-about h3 {
  font-family: var(--font-head);
  font-weight: 800;
  line-height: 1.14;
  letter-spacing: -0.02em;
  color: var(--paper);
  margin: 0;
}

.page-about h1 {
  font-size: clamp(34px, 8.4vw, 68px);
  line-height: 1.03;
  letter-spacing: -0.035em;
  margin: 14px 0 20px;
}

.page-about h2 {
  font-size: clamp(25px, 4.6vw, 40px);
}

.page-about h3 {
  font-size: clamp(16px, 2.3vw, 19px);
}

.page-about .breadcrumb {
  padding-top: clamp(16px, 3vw, 28px);
  display: flex;
  align-items: center;
  gap: 8px;
}

.page-about .breadcrumb__link,
.page-about .breadcrumb__sep,
.page-about .breadcrumb__current {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist);
  text-decoration: none;
}

.page-about .breadcrumb__link:hover {
  color: var(--lime);
}

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

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  padding-top: clamp(20px, 3.4vw, 40px);
}

.page-about .ab-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 5vw, 44px);
  align-items: start;
}

.page-about .ab-hero__rail { order: 2; }
.page-about .ab-hero__flow { order: 1; }

.page-about .ab-toc {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding: 10px 0 6px;
  scrollbar-width: thin;
}

.page-about .ab-toc__item {
  display: flex;
  align-items: baseline;
  gap: 9px;
  flex: 0 0 auto;
  padding: 9px 13px;
  border-left: 2px solid var(--ab-line);
  color: var(--mist);
  text-decoration: none;
  font-size: 13.5px;
  white-space: nowrap;
  transition: color 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.page-about .ab-toc__item:hover,
.page-about .ab-toc__item:focus-visible {
  color: var(--paper);
  border-left-color: var(--lime);
  background: rgba(200, 255, 61, 0.07);
}

.page-about .ab-toc__label { line-height: 1.3; }

.page-about .ab-rot {
  display: none;
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.26em;
  text-transform: uppercase;
  color: var(--mist);
  margin: 22px 0 0;
}

.page-about .lede {
  font-size: clamp(15.5px, 2vw, 18px);
  line-height: 1.82;
  color: var(--sand);
  max-width: 60ch;
  margin: 0 0 clamp(22px, 4vw, 34px);
}

.page-about .ab-stats {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(148px, 1fr));
  gap: 1px;
  margin: 0 0 clamp(26px, 4vw, 40px);
  padding: 1px;
  background: var(--ab-line);
}

.page-about .ab-stats__item {
  background: rgba(16, 28, 51, 0.78);
  padding: 16px 18px;
}

.page-about .ab-stats__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(19px, 2.6vw, 26px);
  letter-spacing: -0.02em;
  color: var(--lime);
}

.page-about .ab-stats__label {
  display: block;
  margin-top: 7px;
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--mist);
}

.page-about .media-frame {
  position: relative;
}

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

.page-about .ab-hero__figure {
  margin: 0;
}

.page-about .ab-hero__figure::before {
  content: "";
  position: absolute;
  top: -9px;
  left: -9px;
  width: 62px;
  height: 6px;
  background: var(--lime);
  transform: skewX(-12deg);
  z-index: 1;
}

/* ---------- 通用章节骨架 ---------- */
.page-about .ab-sec {
  padding-block: clamp(46px, 9vw, 100px);
}

.page-about .ab-sec--blue { background: var(--ink-blue); }
.page-about .ab-sec--indigo { background: var(--ink-indigo); }

.page-about .ab-sec__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(14px, 3vw, 26px);
  align-items: start;
}

.page-about .ab-sec__rail {
  display: flex;
  align-items: baseline;
  gap: 16px;
}

.page-about .ab-sec__num {
  font-family: var(--font-mono);
  font-size: clamp(38px, 9vw, 72px);
  line-height: 1;
  letter-spacing: -0.04em;
  color: transparent;
  -webkit-text-stroke: 1px var(--mist);
}

.page-about .ab-sec__flow h2 {
  margin-bottom: 18px;
}

.page-about .ab-sec__flow > p {
  max-width: 64ch;
  font-size: clamp(15.5px, 1.8vw, 17px);
  line-height: 1.85;
  color: rgba(247, 250, 247, 0.86);
  margin: 0 0 1.05em;
}

/* ---------- 引用块 ---------- */
.page-about .ab-quote {
  position: relative;
  margin: clamp(22px, 4vw, 38px) 0;
  padding: clamp(28px, 3.6vw, 40px) clamp(20px, 3vw, 34px) clamp(20px, 3vw, 28px);
  background: var(--sand);
  border-right: 3px solid var(--wine);
}

.page-about .ab-quote::before {
  content: "品牌手记";
  position: absolute;
  top: 0;
  left: 0;
  padding: 5px 12px;
  background: var(--wine);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
}

.page-about .ab-quote p {
  margin: 0;
  max-width: 46ch;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(17px, 2.4vw, 22px);
  line-height: 1.6;
  color: var(--ink-green);
}

.page-about .ab-quote cite {
  display: block;
  margin-top: 14px;
  font-family: var(--font-mono);
  font-style: normal;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--wine);
}

/* ---------- 协作步骤 ---------- */
.page-about .ab-figure {
  margin: clamp(24px, 4vw, 38px) 0 0;
}

.page-about .ab-steps {
  list-style: none;
  margin: clamp(22px, 4vw, 34px) 0 0;
  padding: 0;
  display: grid;
  gap: clamp(12px, 2.2vw, 18px);
}

.page-about .ab-steps__item {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 12px;
  padding: clamp(15px, 2.6vw, 22px);
  background: rgba(11, 43, 38, 0.56);
  border-left: 2px solid var(--lime);
}

.page-about .ab-steps__num {
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--lime);
  padding-top: 4px;
}

.page-about .ab-steps__item h3 {
  margin: 0 0 8px;
}

.page-about .ab-steps__item p {
  margin: 0;
  font-size: 14.8px;
  line-height: 1.8;
  color: rgba(247, 250, 247, 0.82);
}

/* ---------- 手册四章 ---------- */
.page-about .ab-handbook {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(12px, 2.4vw, 20px);
  margin-top: clamp(22px, 4vw, 34px);
}

.page-about .ab-hb {
  background: rgba(11, 43, 38, 0.74);
  border: 1px solid var(--ab-line);
  padding: clamp(17px, 2.8vw, 26px);
  transition: border-color 0.25s ease, transform 0.25s ease;
}

.page-about .ab-hb:hover {
  border-color: rgba(200, 255, 61, 0.5);
  transform: translateY(-2px);
}

.page-about .ab-hb h3 {
  margin: 14px 0 10px;
}

.page-about .ab-hb p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(247, 250, 247, 0.82);
}

/* ---------- 版本轨迹 ---------- */
.page-about .ab-version {
  list-style: none;
  margin: clamp(22px, 4vw, 34px) 0 0;
  padding: 0;
  border-left: 1px solid rgba(143, 185, 174, 0.45);
  display: grid;
  gap: clamp(22px, 3.4vw, 32px);
}

.page-about .ab-version__item {
  position: relative;
  padding-left: clamp(18px, 3vw, 26px);
}

.page-about .ab-version__item::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 11px;
  width: 9px;
  height: 9px;
  background: var(--lime);
  transform: rotate(45deg);
}

.page-about .ab-version__head {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 8px;
}

.page-about .ab-version__head h3 { margin: 0; }

.page-about .ab-version__item > p {
  margin: 0;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.82;
  color: rgba(247, 250, 247, 0.82);
}

.page-about .ab-version__more {
  display: block;
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.7;
  letter-spacing: 0.03em;
  color: var(--orange);
}

/* ---------- 团队 ---------- */
.page-about .ab-team {
  margin: clamp(20px, 3.6vw, 30px) 0 clamp(20px, 3.6vw, 28px);
}

.page-about .ab-detail {
  border-top: 1px solid var(--ab-line);
}

.page-about .ab-detail:last-child {
  border-bottom: 1px solid var(--ab-line);
}

.page-about .ab-detail__sum {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px 2px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(15px, 2vw, 17px);
  color: var(--paper);
}

.page-about .ab-detail__sum::-webkit-details-marker { display: none; }

.page-about .ab-detail__sum .mono-num {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--lime);
  font-weight: 400;
}

.page-about .ab-detail__sum::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 18px;
  line-height: 1;
  color: var(--lime);
}

.page-about .ab-detail[open] .ab-detail__sum::after {
  content: "−";
}

.page-about .ab-detail p {
  margin: 0 0 18px;
  padding-left: 0;
  max-width: 60ch;
  font-size: 14.8px;
  line-height: 1.82;
  color: rgba(247, 250, 247, 0.8);
}

/* ---------- 底部入口 ---------- */
.page-about .ab-cta {
  padding-block: clamp(46px, 9vw, 92px);
  background: linear-gradient(158deg, var(--ink-indigo) 0%, var(--ink-green) 64%);
  border-top: 1px solid var(--ab-line);
}

.page-about .ab-cta h2 {
  margin-bottom: 16px;
}

.page-about .ab-cta__inner > p {
  max-width: 60ch;
  margin: 0 0 clamp(22px, 4vw, 32px);
  font-size: 15.5px;
  line-height: 1.82;
  color: var(--sand);
}

.page-about .ab-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

/* ---------- 宽屏分屏 ---------- */
@media (min-width: 720px) {
  .page-about .ab-handbook {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 980px) {
  .page-about .ab-hero__grid {
    grid-template-columns: var(--ab-rail) minmax(0, 1fr);
    gap: clamp(40px, 5vw, 76px);
  }

  .page-about .ab-hero__rail {
    order: 1;
    position: sticky;
    top: 92px;
  }

  .page-about .ab-hero__flow { order: 2; }

  .page-about .ab-toc {
    display: block;
    overflow: visible;
    border-top: 1px solid var(--ab-line);
    padding-top: 10px;
  }

  .page-about .ab-toc__item {
    display: block;
    padding: 12px 12px 12px 14px;
    margin-bottom: 2px;
    font-size: 14px;
    white-space: normal;
  }

  .page-about .ab-toc__item .mono-num {
    display: block;
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--lime);
    margin-bottom: 4px;
    letter-spacing: 0.08em;
  }

  .page-about .ab-rot { display: block; }

  .page-about .ab-sec__grid {
    grid-template-columns: var(--ab-rail) minmax(0, 1fr);
    gap: clamp(36px, 5vw, 76px);
  }

  .page-about .ab-sec__rail {
    display: block;
    position: sticky;
    top: 96px;
  }

  .page-about .ab-sec__num {
    display: block;
    font-size: clamp(56px, 5.2vw, 80px);
  }

  .page-about .ab-steps__item {
    grid-template-columns: 44px minmax(0, 1fr);
    gap: 16px;
  }
}

/* ---------- 悬停展开版本说明 ---------- */
@media (hover: hover) and (min-width: 760px) {
  .page-about .ab-version__more {
    opacity: 0;
    transform: translateY(-4px);
    transition: opacity 0.26s ease, transform 0.26s ease;
  }

  .page-about .ab-version__item:hover .ab-version__more,
  .page-about .ab-version__item:focus-within .ab-version__more,
  .page-about .ab-version__item:focus .ab-version__more {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-hb,
  .page-about .ab-version__more,
  .page-about .ab-toc__item {
    transition-duration: 0.01ms !important;
    transform: none !important;
  }
}
<<<END>>>