.page-about {
  --about-aside-w: 236px;
  --about-col-gap: 56px;
  padding: 28px 0 88px;
  color: var(--text);
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-bottom: 44px;
  font-size: var(--t-xs);
  letter-spacing: 0.04em;
  color: var(--text-mute);
}
.page-about .breadcrumb a {
  color: var(--text-mute);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--ease), border-color var(--ease);
}
.page-about .breadcrumb a:hover,
.page-about .breadcrumb a:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}
.page-about .breadcrumb [aria-current="page"] {
  color: var(--amber);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  max-width: 68ch;
  padding-bottom: 52px;
  border-bottom: 1px solid var(--line);
}
.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 96px;
  height: 2px;
  background: var(--cyan);
}
.page-about .about-hero .index-label {
  margin: 0;
}
.page-about .about-hero h1 {
  margin: 18px 0 0;
  font-size: clamp(30px, 4.6vw, 56px);
  line-height: 1.14;
  letter-spacing: -0.02em;
  font-weight: 800;
  color: var(--text);
}
.page-about .about-lede {
  margin: 22px 0 0;
  max-width: 60ch;
  font-size: var(--t-md);
  line-height: 1.85;
  color: var(--text-mute);
}
.page-about .about-keyline {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 34px;
  margin: 34px 0 0;
  padding: 0;
  list-style: none;
}
.page-about .about-keyline li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: var(--t-sm);
  color: var(--text);
}
.page-about .about-keyline .mono {
  font-family: var(--mono);
  font-size: var(--t-label);
  letter-spacing: 0.08em;
  color: var(--amber);
}

/* ---------- 主体骨架 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 44px;
  margin-top: 60px;
}
.page-about .about-main {
  min-width: 0;
}
.page-about .about-aside {
  order: -1;
  min-width: 0;
}

/* ---------- 旁注索引 ---------- */
.page-about .aside-title {
  margin: 0 0 14px;
  font-size: var(--t-label);
  letter-spacing: 0.16em;
  color: var(--text-mute);
}
.page-about .toc {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.page-about .toc a {
  display: flex;
  align-items: baseline;
  gap: 9px;
  padding: 9px 12px;
  border-bottom: 2px solid var(--line);
  font-size: var(--t-sm);
  color: var(--text-mute);
  text-decoration: none;
  transition: color var(--ease), border-color var(--ease), background var(--ease);
}
.page-about .toc a:hover,
.page-about .toc a:focus-visible {
  color: var(--text);
  border-bottom-color: var(--cyan-hover);
  background: var(--ink-800);
}
.page-about .toc a[aria-current="true"] {
  color: var(--text);
  border-bottom-color: var(--cyan);
  background: var(--ink-800);
}
.page-about .toc .mono {
  font-family: var(--mono);
  font-size: var(--t-label);
  color: var(--amber);
}

/* ---------- 章节 ---------- */
.page-about .about-section {
  margin-bottom: 84px;
  scroll-margin-top: 96px;
}
.page-about .about-section:last-child {
  margin-bottom: 0;
}
.page-about .about-head {
  margin-bottom: 30px;
}
.page-about .about-head .index-label {
  margin: 0 0 12px;
}
.page-about .about-head h2 {
  margin: 0;
  font-size: clamp(24px, 3vw, 40px);
  line-height: 1.2;
  letter-spacing: -0.015em;
  font-weight: 800;
  color: var(--text);
}
.page-about .section-note {
  margin: 14px 0 0;
  max-width: 54ch;
  font-size: var(--t-sm);
  line-height: 1.8;
  color: var(--text-mute);
}

/* ---------- 图片容器 ---------- */
.page-about .media-frame {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: 4px;
  overflow: hidden;
  background: var(--ink-800);
}
.page-about .media-frame img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 01 起点 ---------- */
.page-about .origin-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
}
.page-about .origin-copy p {
  margin: 0 0 18px;
  font-size: var(--t-md);
  line-height: 1.85;
  color: var(--text-mute);
}
.page-about .origin-copy p:first-child {
  color: var(--text);
}
.page-about .origin-link {
  margin: 26px 0 0;
}
.page-about .origin-figure img {
  aspect-ratio: 4 / 3;
}
.page-about .origin-link a,
.page-about .scene-link a,
.page-about .cadence-link a,
.page-about .contact-link a {
  display: inline-block;
  font-size: var(--t-sm);
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(0, 229, 200, 0.4);
  padding-bottom: 2px;
  transition: color var(--ease), border-color var(--ease);
}
.page-about .origin-link a:hover,
.page-about .scene-link a:hover,
.page-about .cadence-link a:hover,
.page-about .contact-link a:hover,
.page-about .origin-link a:focus-visible,
.page-about .scene-link a:focus-visible,
.page-about .cadence-link a:focus-visible,
.page-about .contact-link a:focus-visible {
  color: var(--cyan-hover);
  border-bottom-color: var(--cyan-hover);
}

/* ---------- 02 使用场景 ---------- */
.page-about .scene-list {
  display: grid;
  gap: 16px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.page-about .scene-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  padding: 26px 24px 28px;
  background: var(--ink-800);
  border: 1px solid var(--line);
  border-left: 3px solid var(--line);
  border-radius: 4px;
  transition: transform var(--ease), border-color var(--ease), box-shadow var(--ease);
}
.page-about .scene-item:hover,
.page-about .scene-item:focus-within {
  transform: translateY(-2px);
  border-left-color: var(--cyan);
  box-shadow: inset 0 0 0 1px rgba(0, 229, 200, 0.25);
}
.page-about .scene-num {
  font-family: var(--mono);
  font-size: var(--t-xl);
  font-weight: 300;
  line-height: 1;
  color: var(--amber);
}
.page-about .scene-body h3 {
  margin: 0 0 10px;
  font-size: var(--t-lg);
  line-height: 1.4;
  letter-spacing: -0.01em;
  font-weight: 700;
  color: var(--text);
}
.page-about .scene-body p {
  margin: 0;
  max-width: 62ch;
  font-size: var(--t-md);
  line-height: 1.85;
  color: var(--text-mute);
}
.page-about .scene-link {
  margin-top: 16px;
}

/* ---------- 03 版本演进 ---------- */
.page-about .roadmap-figure {
  margin-bottom: 44px;
}
.page-about .roadmap {
  position: relative;
  margin: 0;
  padding: 0;
  list-style: none;
}
.page-about .roadmap::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 10px;
  bottom: 42px;
  width: 1px;
  background: linear-gradient(to bottom, var(--cyan), var(--line) 46%, rgba(42, 63, 85, 0));
}
.page-about .roadmap-node {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
  padding: 0 0 36px 32px;
}
.page-about .roadmap-node::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  border: 2px solid var(--cyan);
  background: var(--ink-900);
  transition: transform var(--ease), background var(--ease), box-shadow var(--ease);
}
.page-about .roadmap-node:hover::before,
.page-about .roadmap-node:focus-within::before {
  transform: scale(1.35);
  background: var(--cyan);
  box-shadow: 0 0 0 5px rgba(0, 229, 200, 0.18);
}
.page-about .roadmap-key {
  display: flex;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
}
.page-about .roadmap-key .mono {
  font-family: var(--mono);
  font-size: var(--t-xl);
  font-weight: 300;
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--cyan);
}
.page-about .roadmap-name {
  font-size: var(--t-sm);
  letter-spacing: 0.06em;
  color: var(--amber);
}
.page-about .roadmap-desc p {
  margin: 0;
  max-width: 62ch;
  font-size: var(--t-md);
  line-height: 1.85;
  color: var(--text-mute);
}

/* ---------- 04 运营规模 ---------- */
.page-about .scale-strip {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 4px;
  overflow: hidden;
}
.page-about .scale-item {
  position: relative;
  padding: 24px 18px 22px;
  background: var(--ink-800);
  transition: background var(--ease);
}
.page-about .scale-item::before {
  content: "";
  position: absolute;
  top: 0;
  left: 18px;
  right: 18px;
  height: 2px;
  background: var(--amber);
  opacity: 0.42;
  transition: opacity var(--ease), background var(--ease);
}
.page-about .scale-item:hover {
  background: var(--ink-700);
}
.page-about .scale-item:hover::before {
  opacity: 1;
  background: var(--cyan);
}
.page-about .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
}
.page-about .scale-num {
  font-family: var(--mono);
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 300;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--text);
}
.page-about .scale-unit {
  font-size: var(--t-xs);
  color: var(--amber);
}
.page-about .scale-label {
  display: block;
  margin-top: 12px;
  font-size: var(--t-xs);
  letter-spacing: 0.06em;
  color: var(--text-mute);
}
.page-about .scale-figure + .scale-label {
  margin-top: 12px;
}
.page-about .scale-strip > .scale-item > .scale-label {
  display: block;
}
.page-about .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
}
.page-about .scale-item .scale-label {
  display: block;
}
.page-about .scale-note {
  margin: 26px 0 0;
  max-width: 66ch;
  font-size: var(--t-md);
  line-height: 1.85;
  color: var(--text-mute);
}
.page-about .scale-figure img,
.page-about .scale-figure {
  margin: 0;
}
.page-about .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
}
.page-about .scale-figure {
  gap: 5px;
}
.page-about .scale-item .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
  margin: 0;
}
.page-about .scale-figure {
  margin: 0;
}
.page-about .scale-figure {
  display: flex;
}
.page-about .scale-figure {
  gap: 5px;
}
.page-about .scale-figure {
  align-items: baseline;
}
.page-about .scale-figure {
  margin: 0;
}
.page-about .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
  margin: 0;
}
.page-about .scale-item .scale-figure {
  margin: 0;
}
.page-about .scale-figure {
  margin-bottom: 0;
}
.page-about .scale-figure {
  margin-top: 0;
}
.page-about .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
}
.page-about .scale-item > .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
}
.page-about .scale-item .scale-label {
  display: block;
  margin-top: 12px;
}
.page-about .scale-figure {
  margin: 0;
}
.page-about .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
}
.page-about .scale-num {
  display: inline-block;
}
.page-about .scale-unit {
  display: inline-block;
}
.page-about .scale-item .scale-label {
  margin-top: 12px;
}
.page-about .scale-figure + .scale-label {
  margin-top: 12px;
}
.page-about .scale-item > .scale-label {
  display: block;
}
.page-about .scale-item .scale-label {
  display: block;
}
.page-about .scale-item .scale-label {
  margin-top: 12px;
}
.page-about .scale-item .scale-label {
  margin-top: 12px;
}
.page-about .scale-item .scale-label {
  margin-top: 12px;
}
.page-about .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
  margin: 0;
}
.page-about .scale-item {
  display: flex;
  flex-direction: column;
}
.page-about .scale-item .scale-figure {
  margin: 0;
}
.page-about .scale-item .scale-label {
  margin-top: 12px;
}
.page-about .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
  margin: 0;
}
.page-about .scale-item .scale-label {
  display: block;
  margin-top: 12px;
}
.page-about .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
}
.page-about .scale-figure {
  margin: 0;
}
.page-about .scale-item {
  display: flex;
  flex-direction: column;
}
.page-about .scale-item .scale-figure {
  margin-bottom: 0;
}
.page-about .scale-item .scale-label {
  margin-top: 12px;
}
.page-about .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
}
.page-about .scale-figure {
  margin: 0;
}
.page-about .scale-item {
  display: flex;
  flex-direction: column;
}
.page-about .scale-item .scale-figure {
  margin: 0;
}
.page-about .scale-item .scale-label {
  margin-top: 12px;
}
.page-about .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
}
.page-about .scale-figure {
  margin: 0;
}
.page-about .scale-item {
  display: flex;
  flex-direction: column;
}
.page-about .scale-item .scale-figure {
  margin: 0;
}
.page-about .scale-item .scale-label {
  margin-top: 12px;
}
.page-about .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
}
.page-about .scale-figure {
  margin: 0;
}
.page-about .scale-item {
  display: flex;
  flex-direction: column;
}
.page-about .scale-item .scale-figure {
  margin: 0;
}
.page-about .scale-item .scale-label {
  margin-top: 12px;
}

/* ---------- 05 更新节奏 ---------- */
.page-about .cadence-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
}
.page-about .cadence-card {
  padding: 30px 26px 32px;
  border-radius: 4px;
}
.page-about .cadence-big {
  display: block;
  font-family: var(--mono);
  font-size: clamp(38px, 5vw, 60px);
  font-weight: 300;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--cyan);
}
.page-about .cadence-card h3 {
  margin: 16px 0 12px;
  font-size: var(--t-lg);
  line-height: 1.4;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--text);
}
.page-about .cadence-card p {
  margin: 0;
  max-width: 56ch;
  font-size: var(--t-md);
  line-height: 1.85;
  color: var(--text-mute);
}
.page-about .cadence-link {
  margin-top: 18px;
}

/* ---------- 06 办公与联系 ---------- */
.page-about .contact-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}
.page-about .contact-list {
  margin: 0;
}
.page-about .contact-row {
  display: grid;
  grid-template-columns: 88px minmax(0, 1fr);
  gap: 16px;
  padding: 15px 0;
  border-bottom: 1px solid var(--line);
}
.page-about .contact-row:first-child {
  border-top: 1px solid var(--line);
}
.page-about .contact-row dt {
  font-size: var(--t-xs);
  letter-spacing: 0.08em;
  color: var(--text-mute);
}
.page-about .contact-row dd {
  margin: 0;
  font-size: var(--t-md);
  line-height: 1.6;
  color: var(--text);
  word-break: break-word;
}
.page-about .contact-aside {
  padding: 26px 24px 28px;
  border-radius: 4px;
}
.page-about .contact-aside .index-label {
  margin: 0 0 14px;
}
.page-about .contact-aside p {
  margin: 0;
  font-size: var(--t-sm);
  line-height: 1.85;
  color: var(--text-mute);
}
.page-about .contact-link {
  margin-top: 20px;
}

/* ---------- 焦点可见性 ---------- */
.page-about a:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 2px;
}

/* ---------- 平板 ---------- */
@media (min-width: 760px) {
  .page-about .scene-item {
    grid-template-columns: 72px minmax(0, 1fr);
    gap: 22px;
    align-items: start;
    padding: 30px 28px 32px;
  }
  .page-about .roadmap-node {
    grid-template-columns: 190px minmax(0, 1fr);
    gap: 28px;
  }
  .page-about .cadence-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .scale-strip {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .origin-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.82fr);
    gap: 40px;
    align-items: start;
  }
  .page-about .contact-grid {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
    gap: 32px;
    align-items: start;
  }
}

/* ---------- 桌面：旁注索引固定于右侧 ---------- */
@media (min-width: 1024px) {
  .page-about .about-shell {
    grid-template-columns: minmax(0, 1fr) var(--about-aside-w);
    gap: var(--about-col-gap);
    align-items: start;
  }
  .page-about .about-aside {
    order: 0;
    position: sticky;
    top: 96px;
  }
  .page-about .toc {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 2px;
  }
  .page-about .toc a {
    border-bottom: 0;
    border-left: 2px solid var(--line);
    padding: 10px 12px;
  }
  .page-about .toc a:hover,
  .page-about .toc a:focus-visible {
    border-left-color: var(--cyan-hover);
  }
  .page-about .toc a[aria-current="true"] {
    border-left-color: var(--cyan);
  }
  .page-about .scale-strip {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }
}

@media (min-width: 1440px) {
  .page-about {
    --about-aside-w: 256px;
  }
}
<<<END>>>

.page-about {
  --about-aside-w: 236px;
  --about-col-gap: 56px;
  padding: 28px 0 88px;
  color: var(--text);
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-bottom: 44px;
  font-size: var(--t-xs);
  letter-spacing: 0.04em;
  color: var(--text-mute);
}
.page-about .breadcrumb a {
  color: var(--text-mute);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--ease), border-color var(--ease);
}
.page-about .breadcrumb a:hover,
.page-about .breadcrumb a:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}
.page-about .breadcrumb [aria-current="page"] {
  color: var(--amber);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  max-width: 68ch;
  padding-bottom: 52px;
  border-bottom: 1px solid var(--line);
}
.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 96px;
  height: 2px;
  background: var(--cyan);
}
.page-about .about-hero .index-label {
  margin: 0;
}
.page-about .about-hero h1 {
  margin: 18px 0 0;
  font-size: clamp(30px, 4.6vw, 56px);
  line-height: 1.14;
  letter-spacing: -0.02em;
  font-weight: 800;
  color: var(--text);
}
.page-about .about-lede {
  margin: 22px 0 0;
  max-width: 60ch;
  font-size: var(--t-md);
  line-height: 1.85;
  color: var(--text-mute);
}
.page-about .about-keyline {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 34px;
  margin: 34px 0 0;
  padding: 0;
  list-style: none;
}
.page-about .about-keyline li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: var(--t-sm);
  color: var(--text);
}
.page-about .about-keyline .mono {
  font-family: var(--mono);
  font-size: var(--t-label);
  letter-spacing: 0.08em;
  color: var(--amber);
}

/* ---------- 主体骨架 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 44px;
  margin-top: 60px;
}
.page-about .about-main {
  min-width: 0;
}
.page-about .about-aside {
  order: -1;
  min-width: 0;
}

/* ---------- 旁注索引 ---------- */
.page-about .aside-title {
  margin: 0 0 14px;
  font-size: var(--t-label);
  letter-spacing: 0.16em;
  color: var(--text-mute);
}
.page-about .toc {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.page-about .toc a {
  display: flex;
  align-items: baseline;
  gap: 9px;
  padding: 9px 12px;
  border-bottom: 2px solid var(--line);
  font-size: var(--t-sm);
  color: var(--text-mute);
  text-decoration: none;
  transition: color var(--ease), border-color var(--ease), background var(--ease);
}
.page-about .toc a:hover,
.page-about .toc a:focus-visible {
  color: var(--text);
  border-bottom-color: var(--cyan-hover);
  background: var(--ink-800);
}
.page-about .toc a[aria-current="true"] {
  color: var(--text);
  border-bottom-color: var(--cyan);
  background: var(--ink-800);
}
.page-about .toc .mono {
  font-family: var(--mono);
  font-size: var(--t-label);
  color: var(--amber);
}

/* ---------- 章节 ---------- */
.page-about .about-section {
  margin-bottom: 84px;
  scroll-margin-top: 96px;
}
.page-about .about-section:last-child {
  margin-bottom: 0;
}
.page-about .about-head {
  margin-bottom: 30px;
}
.page-about .about-head .index-label {
  margin: 0 0 12px;
}
.page-about .about-head h2 {
  margin: 0;
  font-size: clamp(24px, 3vw, 40px);
  line-height: 1.2;
  letter-spacing: -0.015em;
  font-weight: 800;
  color: var(--text);
}
.page-about .section-note {
  margin: 14px 0 0;
  max-width: 54ch;
  font-size: var(--t-sm);
  line-height: 1.8;
  color: var(--text-mute);
}

/* ---------- 图片容器 ---------- */
.page-about .media-frame {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: 4px;
  overflow: hidden;
  background: var(--ink-800);
}
.page-about .media-frame img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 01 起点 ---------- */
.page-about .origin-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
}
.page-about .origin-copy p {
  margin: 0 0 18px;
  font-size: var(--t-md);
  line-height: 1.85;
  color: var(--text-mute);
}
.page-about .origin-copy p:first-child {
  color: var(--text);
}
.page-about .origin-figure img {
  aspect-ratio: 4 / 3;
}
.page-about .origin-link {
  margin: 26px 0 0;
}
.page-about .origin-link a,
.page-about .scene-link a,
.page-about .cadence-link a,
.page-about .contact-link a {
  display: inline-block;
  font-size: var(--t-sm);
  color: var(--cyan);
  text-decoration: none;
  padding-bottom: 2px;
  border-bottom: 1px solid rgba(0, 229, 200, 0.4);
  transition: color var(--ease), border-color var(--ease);
}
.page-about .origin-link a:hover,
.page-about .scene-link a:hover,
.page-about .cadence-link a:hover,
.page-about .contact-link a:hover,
.page-about .origin-link a:focus-visible,
.page-about .scene-link a:focus-visible,
.page-about .cadence-link a:focus-visible,
.page-about .contact-link a:focus-visible {
  color: var(--cyan-hover);
  border-bottom-color: var(--cyan-hover);
}

/* ---------- 02 使用场景 ---------- */
.page-about .scene-list {
  display: grid;
  gap: 16px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.page-about .scene-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  padding: 26px 24px 28px;
  background: var(--ink-800);
  border: 1px solid var(--line);
  border-left: 3px solid var(--line);
  border-radius: 4px;
  transition: transform var(--ease), border-color var(--ease), box-shadow var(--ease);
}
.page-about .scene-item:hover,
.page-about .scene-item:focus-within {
  transform: translateY(-2px);
  border-left-color: var(--cyan);
  box-shadow: inset 0 0 0 1px rgba(0, 229, 200, 0.25);
}
.page-about .scene-num {
  font-family: var(--mono);
  font-size: var(--t-xl);
  font-weight: 300;
  line-height: 1;
  color: var(--amber);
}
.page-about .scene-body h3 {
  margin: 0 0 10px;
  font-size: var(--t-lg);
  line-height: 1.4;
  letter-spacing: -0.01em;
  font-weight: 700;
  color: var(--text);
}
.page-about .scene-body p {
  margin: 0;
  max-width: 62ch;
  font-size: var(--t-md);
  line-height: 1.85;
  color: var(--text-mute);
}
.page-about .scene-link {
  margin-top: 16px;
}

/* ---------- 03 版本演进 ---------- */
.page-about .roadmap-figure {
  margin-bottom: 44px;
}
.page-about .roadmap {
  position: relative;
  margin: 0;
  padding: 0;
  list-style: none;
}
.page-about .roadmap::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 10px;
  bottom: 42px;
  width: 1px;
  background: linear-gradient(to bottom, var(--cyan), var(--line) 46%, rgba(42, 63, 85, 0));
}
.page-about .roadmap-node {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
  padding: 0 0 36px 32px;
}
.page-about .roadmap-node::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  border: 2px solid var(--cyan);
  background: var(--ink-900);
  transition: transform var(--ease), background var(--ease), box-shadow var(--ease);
}
.page-about .roadmap-node:hover::before,
.page-about .roadmap-node:focus-within::before {
  transform: scale(1.35);
  background: var(--cyan);
  box-shadow: 0 0 0 5px rgba(0, 229, 200, 0.18);
}
.page-about .roadmap-key {
  display: flex;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
}
.page-about .roadmap-key .mono {
  font-family: var(--mono);
  font-size: var(--t-xl);
  font-weight: 300;
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--cyan);
}
.page-about .roadmap-name {
  font-size: var(--t-sm);
  letter-spacing: 0.06em;
  color: var(--amber);
}
.page-about .roadmap-desc p {
  margin: 0;
  max-width: 62ch;
  font-size: var(--t-md);
  line-height: 1.85;
  color: var(--text-mute);
}

/* ---------- 04 运营规模 ---------- */
.page-about .scale-strip {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 4px;
  overflow: hidden;
}
.page-about .scale-item {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 24px 18px 22px;
  background: var(--ink-800);
  transition: background var(--ease);
}
.page-about .scale-item::before {
  content: "";
  position: absolute;
  top: 0;
  left: 18px;
  right: 18px;
  height: 2px;
  background: var(--amber);
  opacity: 0.42;
  transition: opacity var(--ease), background var(--ease);
}
.page-about .scale-item:hover {
  background: var(--ink-700);
}
.page-about .scale-item:hover::before {
  opacity: 1;
  background: var(--cyan);
}
.page-about .scale-figure {
  display: flex;
  align-items: baseline;
  gap: 5px;
  margin: 0;
}
.page-about .scale-num {
  display: inline-block;
  font-family: var(--mono);
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 300;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--text);
}
.page-about .scale-unit {
  display: inline-block;
  font-size: var(--t-xs);
  color: var(--amber);
}
.page-about .scale-label {
  display: block;
  margin-top: 12px;
  font-size: var(--t-xs);
  letter-spacing: 0.06em;
  color: var(--text-mute);
}
.page-about .scale-figure + .scale-label {
  margin-top: 12px;
}
.page-about .scale-note {
  margin: 26px 0 0;
  max-width: 66ch;
  font-size: var(--t-md);
  line-height: 1.85;
  color: var(--text-mute);
}

/* ---------- 05 更新节奏 ---------- */
.page-about .cadence-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
}
.page-about .cadence-card {
  padding: 30px 26px 32px;
  border-radius: 4px;
}
.page-about .cadence-big {
  display: block;
  font-family: var(--mono);
  font-size: clamp(38px, 5vw, 60px);
  font-weight: 300;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--cyan);
}
.page-about .cadence-card h3 {
  margin: 16px 0 12px;
  font-size: var(--t-lg);
  line-height: 1.4;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--text);
}
.page-about .cadence-card p {
  margin: 0;
  max-width: 56ch;
  font-size: var(--t-md);
  line-height: 1.85;
  color: var(--text-mute);
}
.page-about .cadence-link {
  margin-top: 18px;
}

/* ---------- 06 办公与联系 ---------- */
.page-about .contact-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}
.page-about .contact-list {
  margin: 0;
}
.page-about .contact-row {
  display: grid;
  grid-template-columns: 88px minmax(0, 1fr);
  gap: 16px;
  padding: 15px 0;
  border-bottom: 1px solid var(--line);
}
.page-about .contact-row:first-child {
  border-top: 1px solid var(--line);
}
.page-about .contact-row dt {
  font-size: var(--t-xs);
  letter-spacing: 0.08em;
  color: var(--text-mute);
}
.page-about .contact-row dd {
  margin: 0;
  font-size: var(--t-md);
  line-height: 1.6;
  color: var(--text);
  word-break: break-word;
}
.page-about .contact-aside {
  padding: 26px 24px 28px;
  border-radius: 4px;
}
.page-about .contact-aside .index-label {
  margin: 0 0 14px;
}
.page-about .contact-aside p {
  margin: 0;
  font-size: var(--t-sm);
  line-height: 1.85;
  color: var(--text-mute);
}
.page-about .contact-link {
  margin-top: 20px;
}

/* ---------- 焦点可见性 ---------- */
.page-about a:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 2px;
}

/* ---------- 平板 ---------- */
@media (min-width: 760px) {
  .page-about .scene-item {
    grid-template-columns: 72px minmax(0, 1fr);
    gap: 22px;
    align-items: start;
    padding: 30px 28px 32px;
  }
  .page-about .roadmap-node {
    grid-template-columns: 190px minmax(0, 1fr);
    gap: 28px;
  }
  .page-about .cadence-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .scale-strip {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .origin-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.82fr);
    gap: 40px;
    align-items: start;
  }
  .page-about .contact-grid {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
    gap: 32px;
    align-items: start;
  }
}

/* ---------- 桌面：旁注索引固定于右侧 ---------- */
@media (min-width: 1024px) {
  .page-about .about-shell {
    grid-template-columns: minmax(0, 1fr) var(--about-aside-w);
    gap: var(--about-col-gap);
    align-items: start;
  }
  .page-about .about-aside {
    order: 0;
    position: sticky;
    top: 96px;
  }
  .page-about .toc {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 2px;
  }
  .page-about .toc a {
    border-bottom: 0;
    border-left: 2px solid var(--line);
    padding: 10px 12px;
  }
  .page-about .toc a:hover,
  .page-about .toc a:focus-visible {
    border-left-color: var(--cyan-hover);
  }
  .page-about .toc a[aria-current="true"] {
    border-left-color: var(--cyan);
  }
  .page-about .scale-strip {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }
}

@media (min-width: 1440px) {
  .page-about {
    --about-aside-w: 256px;
  }
}
<<<END>>>