.page-about {
  --about-pad: clamp(18px, 4vw, 40px);
  --about-flow-w: 760px;
  background: radial-gradient(980px 520px at 88% -8%, rgba(182, 255, 60, 0.07), transparent 62%), var(--ink-900);
  color: var(--text);
  padding-block: 0 clamp(56px, 9vw, 110px);
}

.page-about *,
.page-about *::before,
.page-about *::after {
  box-sizing: border-box;
}

.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
  width: min(1180px, 100%);
  margin-inline: auto;
  padding: 22px var(--about-pad) 0;
}

/* ---------- 编号索引 ---------- */
.page-about .about-index {
  position: relative;
  padding-top: 16px;
  border-top: 2px solid var(--lime);
}

.page-about .about-index-label {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.24em;
  color: var(--muted);
}

.page-about .about-index-list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}

.page-about .about-index-list::-webkit-scrollbar {
  display: none;
}

.page-about .about-index-link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  flex: 0 0 auto;
  padding: 8px 12px;
  border: 1px solid var(--ink-line);
  border-radius: var(--radius-b);
  color: var(--muted);
  font-size: 14px;
  text-decoration: none;
  white-space: nowrap;
  transition: color var(--dur) ease, border-color var(--dur) ease, background-color var(--dur) ease;
}

.page-about .about-index-num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--lime);
}

.page-about .about-index-link:hover,
.page-about .about-index-link:focus-visible {
  color: var(--text);
  border-color: var(--lime);
  background: rgba(182, 255, 60, 0.08);
  outline: none;
}

.page-about .about-index-link.is-current {
  color: var(--ink-900);
  background: var(--lime);
  border-color: var(--lime);
  font-weight: 700;
}

.page-about .about-index-link.is-current .about-index-num {
  color: var(--ink-900);
}

.page-about .about-index-note {
  margin: 10px 0 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--muted);
}

/* ---------- 正文列 ---------- */
.page-about .about-flow {
  min-width: 0;
  max-width: var(--about-flow-w);
}

.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 26px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.page-about .about-hero {
  padding-bottom: clamp(30px, 5vw, 54px);
}

.page-about .about-title {
  margin: 14px 0 0;
  font-size: clamp(30px, 6.6vw, 56px);
  font-weight: 900;
  line-height: 1.08;
  letter-spacing: -0.012em;
  color: var(--text);
}

.page-about .about-title em {
  font-style: normal;
  color: var(--lime);
}

.page-about .about-lede {
  margin: 20px 0 0;
  max-width: 54ch;
  font-size: 16.5px;
  line-height: 1.85;
  color: var(--text);
}

.page-about .about-lede--tight {
  color: var(--muted);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 30px 0 0;
  padding: 0;
  background: var(--ink-line);
  border: 1px solid var(--ink-line);
  border-radius: var(--radius-a);
  overflow: hidden;
}

.page-about .about-fact {
  padding: 14px 16px;
  background: var(--ink-850);
}

.page-about .about-fact dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--muted);
}

.page-about .about-fact dd {
  margin: 7px 0 0;
  font-size: 16px;
  font-weight: 700;
  line-height: 1.3;
  color: var(--text);
}

/* ---------- 图片 ---------- */
.page-about .about-media {
  margin: 0;
  animation: aboutFade 0.6s ease;
}

.page-about .about-media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-a);
  object-fit: cover;
  background: var(--ink-800);
}

.page-about .about-media--hero {
  margin-top: clamp(4px, 2vw, 14px);
}

.page-about .media-caption {
  margin-top: 12px;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--muted);
}

@keyframes aboutFade {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  padding-block: clamp(38px, 6.5vw, 78px);
}

.page-about .about-chapter + .about-chapter {
  border-top: 1px solid var(--ink-line);
}

.page-about .about-chapter-head {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin-bottom: clamp(20px, 3vw, 30px);
}

.page-about .about-chapter-num {
  flex: 0 0 auto;
  margin-top: 5px;
  padding: 3px 8px;
  border-radius: 4px 0 4px 0;
  background: var(--lime);
  color: var(--ink-900);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.1em;
}

.page-about .about-kicker {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--muted);
}

.page-about .about-chapter-title {
  margin: 0;
  font-size: clamp(21px, 3.9vw, 32px);
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: -0.006em;
  color: var(--text);
}

.page-about .about-body {
  max-width: 62ch;
}

.page-about .about-body p {
  margin: 0 0 1.15em;
  font-size: 16.5px;
  line-height: 1.85;
  color: var(--text);
}

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

/* ---------- 内容结构 ---------- */
.page-about .about-structure {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
}

.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  margin: 26px 0 0;
}

.page-about .about-inline-link {
  position: relative;
  display: inline-block;
  padding-bottom: 3px;
  color: var(--lime);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
}

.page-about .about-inline-link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 1px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--dur) ease;
}

.page-about .about-inline-link:hover::after,
.page-about .about-inline-link:focus-visible::after {
  transform: scaleX(1);
}

.page-about .about-inline-link:focus-visible {
  outline: none;
}

/* ---------- 更新节奏 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
}

.page-about .about-step {
  position: relative;
  padding: 0 0 26px 28px;
  border-left: 2px dashed var(--ink-line);
}

.page-about .about-step:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.page-about .about-step::before {
  content: "";
  position: absolute;
  left: -7px;
  top: 4px;
  width: 12px;
  height: 12px;
  border: 2px solid var(--lime);
  border-radius: 50%;
  background: var(--ink-900);
}

.page-about .about-step-time {
  display: inline-block;
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--lime);
}

.page-about .about-step-title {
  margin: 0 0 8px;
  font-size: 16.5px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--text);
}

.page-about .about-step p {
  margin: 0;
  max-width: 46ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-media--wide {
  margin-top: clamp(28px, 4vw, 46px);
}

/* ---------- 长期整理 ---------- */
.page-about .about-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .about-card {
  padding: 22px 22px 20px;
  background: var(--ink-850);
  border: 1px solid var(--ink-line);
  border-radius: var(--radius-a);
  transition: border-color var(--dur) ease, transform var(--dur) ease;
}

.page-about .about-card:hover {
  border-color: var(--lime);
  transform: translateY(-2px);
}

.page-about .about-card .card-title {
  margin: 0 0 10px;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--text);
}

.page-about .about-card .card-title::before {
  content: "";
  display: inline-block;
  width: 14px;
  height: 2px;
  margin-right: 9px;
  vertical-align: middle;
  background: var(--lime);
}

.page-about .about-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 联系 ---------- */
.page-about .about-contact {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 28px 0 0;
  padding: 0;
  background: var(--ink-line);
  border: 1px solid var(--ink-line);
  border-radius: var(--radius-a);
  overflow: hidden;
}

.page-about .about-contact-item {
  padding: 18px;
  background: var(--ink-850);
}

.page-about .about-contact-item dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--muted);
}

.page-about .about-contact-item dd {
  margin: 8px 0 0;
  font-size: 15px;
  line-height: 1.6;
  color: var(--text);
  word-break: break-word;
}

.page-about .about-contact-item dd a {
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid rgba(182, 255, 60, 0.35);
  transition: color var(--dur) ease, border-color var(--dur) ease;
}

.page-about .about-contact-item dd a:hover,
.page-about .about-contact-item dd a:focus-visible {
  color: var(--lime-soft);
  border-bottom-color: var(--lime-soft);
  outline: none;
}

.page-about .about-note {
  margin: 20px 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--ink-line);
  font-size: 13px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 平板及以上 ---------- */
@media (min-width: 720px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px;
  }

  .page-about .about-structure {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
    gap: 36px;
    align-items: start;
  }

  .page-about .about-structure .about-media {
    margin-top: 8px;
  }

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

/* ---------- 桌面：侧向编号轨道 ---------- */
@media (min-width: 980px) {
  .page-about .about-shell {
    grid-template-columns: 190px minmax(0, 1fr);
    gap: clamp(36px, 5vw, 76px);
    padding-top: 62px;
  }

  .page-about .about-index {
    position: sticky;
    top: 40px;
    align-self: start;
    padding: 4px 0 0 20px;
    border-top: 0;
    border-left: 2px solid var(--lime);
  }

  .page-about .about-index-list {
    flex-direction: column;
    gap: 2px;
    padding-bottom: 0;
    overflow: visible;
  }

  .page-about .about-index-link {
    padding: 7px 0;
    border: 0;
    border-radius: 0;
    background: none;
  }

  .page-about .about-index-link:hover,
  .page-about .about-index-link:focus-visible {
    background: none;
    border: 0;
    color: var(--lime);
  }

  .page-about .about-index-link.is-current {
    color: var(--lime);
    background: none;
    border: 0;
  }

  .page-about .about-index-link.is-current .about-index-num {
    color: var(--lime);
  }

  .page-about .about-index-note {
    writing-mode: vertical-rl;
    margin-top: 30px;
    letter-spacing: 0.3em;
  }

  .page-about .about-timeline {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 20px;
    margin-top: 40px;
  }

  .page-about .about-step {
    padding: 26px 0 0;
    border-left: 0;
    border-top: 1px dashed var(--ink-line);
  }

  .page-about .about-step:last-child {
    padding-bottom: 0;
    border-left-color: currentColor;
    border-top-color: transparent;
  }

  .page-about .about-step::before {
    left: 0;
    top: -7px;
  }

  .page-about .about-step p {
    max-width: none;
  }
}

/* ---------- 减弱动态效果 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-media {
    animation: none;
  }

  .page-about .about-card:hover {
    transform: none;
  }

  .page-about .about-inline-link::after {
    transition: none;
  }
}
<<<END>>>