.page-about {
  --about-rule: rgba(77, 240, 200, 0.14);
  --about-soft: rgba(143, 168, 160, 0.2);
  overflow-wrap: break-word;
}

/* ===== 首屏 ===== */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding: clamp(34px, 5vw, 80px) 0 clamp(28px, 4vw, 56px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  z-index: -1;
  top: -34%;
  right: -16%;
  width: min(820px, 82vw);
  aspect-ratio: 1;
  border-radius: 44% 56% 58% 42% / 52% 44% 56% 48%;
  background: linear-gradient(135deg, rgba(77, 240, 200, 0.17), rgba(8, 23, 17, 0) 64%);
  transform: rotate(-15deg);
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  z-index: -1;
  left: -12%;
  bottom: -40%;
  width: min(600px, 66vw);
  aspect-ratio: 2 / 1;
  border-radius: var(--pill);
  background: linear-gradient(90deg, rgba(245, 184, 75, 0.2), rgba(255, 90, 95, 0.07) 68%, transparent);
  transform: rotate(-8deg);
  pointer-events: none;
}

.page-about .about-hero__inner {
  display: grid;
  gap: clamp(26px, 4vw, 52px);
  align-items: center;
}

.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--mist);
}

.page-about .breadcrumb a {
  color: var(--cyan-soft);
  text-decoration: none;
}

.page-about .breadcrumb a:hover {
  color: var(--white);
}

.page-about .about-hero .eyebrow {
  margin: clamp(16px, 2.4vw, 26px) 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--cyan);
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(32px, 5vw, 68px);
  line-height: 1.1;
  letter-spacing: -0.03em;
  color: var(--white);
  max-width: 15ch;
}

.page-about .about-hero__desc {
  margin: 20px 0 0;
  max-width: 54ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--white);
}

.page-about .about-hero__stats {
  list-style: none;
  margin: clamp(26px, 3.4vw, 44px) 0 0;
  padding: 0;
  display: grid;
  gap: 18px;
  grid-template-columns: repeat(auto-fit, minmax(128px, 1fr));
}

.page-about .about-hero__stats li {
  padding-left: 14px;
  border-left: 1px solid var(--about-rule);
}

.page-about .about-hero__stats li:first-child {
  border-left-color: rgba(245, 184, 75, 0.55);
}

.page-about .about-stat__mark {
  font-size: 0.5em;
  vertical-align: super;
  color: var(--cyan-soft);
}

.page-about .about-hero__stats .num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(30px, 4vw, 46px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .about-stat__label {
  display: block;
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--mist);
}

.page-about .about-hero__figure {
  position: relative;
  margin: 0;
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--turf);
  box-shadow: var(--shadow);
}

.page-about .about-hero__figure::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  z-index: 2;
  width: 44%;
  height: 8px;
  background: linear-gradient(90deg, var(--amber), var(--cyan));
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 14 / 9;
  object-fit: cover;
}

.page-about .about-hero__figure figcaption {
  padding: 12px 18px 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  color: var(--mist);
  background: var(--turf-2);
  border-top: 1px solid var(--about-rule);
}

/* ===== 主体骨架 ===== */
.page-about .about-body {
  display: grid;
  gap: clamp(28px, 4vw, 56px);
  padding-bottom: clamp(48px, 7vw, 96px);
}

.page-about .about-rail {
  display: grid;
  gap: 26px;
  align-content: start;
}

.page-about .about-flow {
  display: grid;
  gap: clamp(18px, 3vw, 32px);
  min-width: 0;
}

/* ===== 目录 ===== */
.page-about .toc {
  display: grid;
  gap: 6px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--about-rule);
}

.page-about .toc__title {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--mist);
}

.page-about .toc__link {
  display: block;
  padding: 8px 12px 8px 14px;
  border-radius: var(--r-sm);
  border-left: 2px solid transparent;
  font-size: 14px;
  line-height: 1.5;
  color: var(--mist);
  text-decoration: none;
  transition: color 0.25s ease, background 0.25s ease, border-color 0.25s ease;
}

.page-about .toc__link:hover {
  color: var(--white);
  background: rgba(77, 240, 200, 0.07);
}

.page-about .toc__link[data-current] {
  color: var(--night);
  background: var(--cyan);
  border-left-color: var(--amber);
  font-weight: 500;
}

/* ===== 版本轴 ===== */
.page-about .version-rail {
  display: grid;
  gap: 12px;
}

.page-about .version-rail__title {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--mist);
}

.page-about .version-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .version-node {
  position: relative;
  padding-left: 20px;
}

.page-about .version-node::before {
  content: "";
  position: absolute;
  left: 1px;
  top: 6px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(77, 240, 200, 0.12);
}

.page-about .version-node::after {
  content: "";
  position: absolute;
  left: 4.5px;
  top: 20px;
  bottom: -16px;
  width: 1px;
  background: var(--about-rule);
}

.page-about .version-node:last-child::after {
  display: none;
}

.page-about .version-node__code {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--cyan-soft);
}

.page-about .version-node__stage {
  display: block;
  margin-top: 3px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--mist);
}

/* ===== 章节 ===== */
.page-about .chapter {
  padding: clamp(28px, 4vw, 50px) 0;
  border-top: 1px solid var(--about-rule);
  scroll-margin-top: 112px;
}

.page-about .chapter:first-child {
  border-top: none;
  padding-top: 0;
}

.page-about .chapter__idx {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.22em;
  color: var(--cyan);
}

.page-about .chapter__title {
  margin: 0;
  max-width: 22ch;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(25px, 3.2vw, 42px);
  line-height: 1.18;
  letter-spacing: -0.025em;
  color: var(--white);
}

.page-about .chapter__note {
  margin: 12px 0 0;
  max-width: 60ch;
  font-size: 13px;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .prose {
  max-width: 68ch;
  margin-top: clamp(16px, 2.2vw, 26px);
}

.page-about .prose p {
  margin: 0 0 1.1em;
  font-size: clamp(15px, 1.5vw, 16.5px);
  line-height: 1.85;
  color: var(--white);
}

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

.page-about .prose a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(77, 240, 200, 0.4);
}

.page-about .prose a:hover {
  border-bottom-color: var(--cyan);
}

/* ===== 条款卡片 ===== */
.page-about .clause-list {
  list-style: none;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .clause {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 14px;
  padding: 18px 20px;
  border-radius: var(--r-md);
  border: 1px solid rgba(169, 118, 42, 0.34);
  background: linear-gradient(160deg, rgba(15, 42, 32, 0.92), rgba(8, 23, 17, 0.6));
}

.page-about .clause__no {
  padding-top: 2px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--amber);
}

.page-about .clause__title {
  margin: 0 0 6px;
  font-size: 16px;
  font-weight: 500;
  color: var(--white);
}

.page-about .clause__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
}

/* ===== 版本迭代 ===== */
.page-about .version-figure {
  position: relative;
  margin: clamp(22px, 3vw, 32px) 0 0;
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--turf-2);
}

.page-about .version-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 12 / 7;
  object-fit: cover;
}

.page-about .version-figure figcaption {
  padding: 12px 18px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  color: var(--mist);
  border-top: 1px solid var(--about-rule);
}

.page-about .version-track {
  list-style: none;
  margin: clamp(20px, 3vw, 30px) 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .version-card {
  position: relative;
  padding: 20px 22px 22px;
  border-radius: var(--r-md);
  border: 1px solid var(--about-rule);
  background: var(--turf-2);
  overflow: hidden;
}

.page-about .version-card::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: var(--cyan);
}

.page-about .version-card--amber::before {
  background: var(--amber);
}

.page-about .version-card--red::before {
  background: var(--red);
}

.page-about .version-card__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
}

.page-about .version-card__code {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.04em;
  color: var(--cyan);
}

.page-about .version-card__stage {
  padding: 3px 10px;
  border-radius: var(--pill);
  border: 1px solid var(--about-soft);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--mist);
}

.page-about .version-card__title {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 500;
  line-height: 1.45;
  color: var(--white);
}

.page-about .version-card__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
}

/* ===== 递补折叠 ===== */
.page-about .rule-folds {
  margin-top: clamp(20px, 3vw, 30px);
  display: grid;
  gap: 12px;
}

.page-about .rule-fold {
  border-radius: var(--r-md);
  border: 1px solid var(--about-rule);
  background: var(--turf-2);
  overflow: hidden;
}

.page-about .rule-fold summary {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px 20px;
  font-size: 15px;
  font-weight: 500;
  line-height: 1.6;
  color: var(--white);
  cursor: pointer;
  list-style: none;
}

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

.page-about .rule-fold summary::before {
  content: "+";
  flex: none;
  width: 18px;
  text-align: center;
  font-family: var(--font-mono);
  font-size: 17px;
  line-height: 1;
  color: var(--cyan);
}

.page-about .rule-fold[open] summary::before {
  content: "–";
}

.page-about .rule-fold summary:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: -2px;
}

.page-about .rule-fold .fold-body {
  padding: 14px 20px 18px;
  border-top: 1px solid var(--about-rule);
}

.page-about .rule-fold .fold-body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .rule-fold .fold-body a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(77, 240, 200, 0.4);
}

/* ===== 四条数据线 ===== */
.page-about .line-grid {
  margin-top: clamp(22px, 3vw, 34px);
  display: grid;
  gap: 14px;
}

.page-about .line-card {
  display: block;
  padding: 20px 22px;
  border-radius: var(--r-md);
  border: 1px solid var(--about-rule);
  background: linear-gradient(150deg, rgba(77, 240, 200, 0.08), rgba(8, 23, 17, 0.4));
  text-decoration: none;
  color: inherit;
  transition: transform 0.3s ease, border-color 0.3s ease;
}

.page-about .line-card--static {
  background: linear-gradient(150deg, rgba(245, 184, 75, 0.1), rgba(8, 23, 17, 0.4));
}

.page-about a.line-card:hover {
  transform: translateY(-3px);
  border-color: rgba(77, 240, 200, 0.5);
}

.page-about .line-card__tag {
  display: inline-block;
  margin-bottom: 12px;
  padding: 4px 10px;
  border-radius: var(--pill);
  background: rgba(77, 240, 200, 0.14);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.page-about .line-card--static .line-card__tag {
  background: rgba(245, 184, 75, 0.16);
  color: var(--amber);
}

.page-about .line-card__title {
  margin: 0 0 8px;
  font-size: 18px;
  font-weight: 500;
  color: var(--white);
}

.page-about .line-card__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
}

/* ===== 校对流程 ===== */
.page-about .role-grid {
  margin-top: clamp(22px, 3vw, 32px);
  display: grid;
  gap: 12px;
}

.page-about .role {
  padding: 18px;
  border-radius: var(--r-md);
  border-top: 2px solid var(--cyan);
  background: var(--turf-2);
}

.page-about .role__count {
  margin: 0;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 30px;
  line-height: 1;
  color: var(--white);
  font-variant-numeric: tabular-nums;
}

.page-about .role__name {
  margin: 10px 0 6px;
  font-size: 15px;
  color: var(--cyan-soft);
}

.page-about .role__text {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .workflow-figure {
  margin: clamp(22px, 3vw, 34px) 0 0;
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--turf-2);
}

.page-about .workflow-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .workflow-figure figcaption {
  padding: 12px 18px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  color: var(--mist);
  border-top: 1px solid var(--about-rule);
}

/* ===== 里程碑 ===== */
.page-about .milestones {
  list-style: none;
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 0;
}

.page-about .milestone {
  position: relative;
  padding: 0 0 clamp(24px, 3vw, 34px) 30px;
  border-left: 1px solid var(--about-soft);
}

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

.page-about .milestone::before {
  content: "";
  position: absolute;
  left: -6px;
  top: 5px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--night);
  border: 2px solid var(--cyan);
}

.page-about .milestone__stage {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .milestone__title {
  margin: 8px 0 8px;
  font-size: 18px;
  font-weight: 500;
  line-height: 1.45;
  color: var(--white);
}

.page-about .milestone__text {
  margin: 0;
  max-width: 64ch;
  font-size: 14px;
  line-height: 1.85;
  color: var(--mist);
}

/* ===== 收尾 ===== */
.page-about .about-cta {
  margin-top: clamp(26px, 4vw, 42px);
  padding: clamp(24px, 4vw, 40px);
  border-radius: var(--r-lg);
  border: 1px solid rgba(77, 240, 200, 0.3);
  background: linear-gradient(135deg, rgba(77, 240, 200, 0.14), rgba(15, 42, 32, 0.72) 58%);
  display: grid;
  gap: 20px;
}

.page-about .about-cta__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(20px, 2.4vw, 28px);
  line-height: 1.25;
  letter-spacing: -0.01em;
  color: var(--white);
}

.page-about .about-cta__text {
  margin: 0;
  max-width: 58ch;
  font-size: 14px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ===== 响应式 ===== */
@media (min-width: 640px) {
  .page-about .role-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 720px) {
  .page-about .clause-list,
  .page-about .version-track,
  .page-about .line-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 760px) {
  .page-about .about-cta {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }
}

@media (min-width: 880px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  }
}

@media (min-width: 1000px) {
  .page-about .about-body {
    grid-template-columns: 246px minmax(0, 1fr);
  }

  .page-about .about-rail {
    position: sticky;
    top: 104px;
    align-self: start;
  }

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

@media (max-width: 520px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
  }

  .page-about .about-hero__stats li:last-child {
    grid-column: 1 / -1;
  }

  .page-about .about-cta__actions .btn {
    width: 100%;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .toc__link,
  .page-about .line-card {
    transition: none;
  }

  .page-about a.line-card:hover {
    transform: none;
  }
}
<<<END>>>