.page-about {
  --rail-w: 208px;
  --col-gap: 64px;
  --line-gold: rgba(201, 162, 39, .28);
  --line-grey: rgba(134, 147, 140, .22);
}

/* ---------- 首屏 ---------- */

.page-about .about-masthead {
  position: relative;
  padding: calc(var(--header-h) + var(--s5)) 0 var(--s5);
  background:
    radial-gradient(120% 100% at 10% 0%, rgba(53, 224, 210, .08), transparent 58%),
    linear-gradient(180deg, #0A1C17 0%, #102A22 100%);
  border-bottom: 1px solid var(--line-gold);
  overflow: hidden;
}

.page-about .about-masthead::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(201, 162, 39, .055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(201, 162, 39, .055) 1px, transparent 1px);
  background-size: 64px 64px;
  pointer-events: none;
  -webkit-mask-image: linear-gradient(180deg, transparent 0%, #000 35%, rgba(0, 0, 0, .35) 100%);
  mask-image: linear-gradient(180deg, transparent 0%, #000 35%, rgba(0, 0, 0, .35) 100%);
}

.page-about .about-masthead .shell {
  position: relative;
  z-index: 1;
}

.page-about .masthead-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--s4);
  margin-top: var(--s4);
}

.page-about h1 {
  font-family: var(--font-display);
  font-size: clamp(36px, 8vw, 56px);
  font-weight: 700;
  letter-spacing: .02em;
  line-height: 1.12;
  color: var(--white);
  margin: var(--s2) 0 0;
}

.page-about .about-lede {
  max-width: 34em;
  font-size: 17px;
  line-height: 1.9;
  color: var(--paper);
  margin: var(--s3) 0 0;
}

.page-about .masthead-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  background: var(--line-gold);
  border: 1px solid var(--line-gold);
}

.page-about .ms-item {
  background: rgba(10, 28, 23, .88);
  padding: var(--s2) var(--s3);
}

.page-about .ms-item dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--index);
  margin-bottom: 8px;
}

.page-about .ms-item dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 28px;
  font-weight: 500;
  line-height: 1;
  color: var(--gold-hi);
}

.page-about .ms-item dd small {
  font-size: 12px;
  color: var(--index);
  margin-left: 4px;
}

/* ---------- 布局骨架 ---------- */

.page-about .about-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--s4);
  padding-top: var(--s5);
  padding-bottom: var(--s6);
}

.page-about .about-rail {
  display: none;
}

.page-about .rail-title {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--index);
  margin: 0 0 var(--s2);
}

.page-about .index-rail {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.page-about .index-link {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 7px 0;
  text-decoration: none;
  color: var(--index);
  font-size: 14px;
  line-height: 1.5;
  border-left: 2px solid transparent;
  padding-left: 10px;
  margin-left: -12px;
  transition: color .18s var(--ease), border-color .18s var(--ease);
}

.page-about .index-link .idx {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--gold);
  letter-spacing: .08em;
}

.page-about .index-link:hover,
.page-about .index-link:focus-visible {
  color: var(--white);
  border-left-color: rgba(201, 162, 39, .5);
}

.page-about .index-link.is-current {
  color: var(--gold-hi);
  border-left-color: var(--gold-hi);
}

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

/* ---------- 章节 ---------- */

.page-about .about-body {
  counter-reset: ch;
  min-width: 0;
}

.page-about .ch {
  counter-increment: ch;
  padding-bottom: var(--s5);
  margin-bottom: var(--s5);
  border-bottom: 1px solid var(--line-grey);
  scroll-margin-top: calc(var(--header-h-solid) + 20px);
}

.page-about .ch:last-child {
  border-bottom: 0;
  margin-bottom: 0;
  padding-bottom: 0;
}

.page-about .ch-head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: var(--s3);
  align-items: start;
  margin-bottom: var(--s3);
}

.page-about .ch-num {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border: 1px solid var(--gold);
  background: rgba(201, 162, 39, .08);
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 500;
  color: var(--gold-hi);
  flex: none;
}

.page-about .ch-num::before {
  content: counter(ch, decimal-leading-zero);
}

.page-about .ch-head h2 {
  margin: 4px 0 0;
  font-family: var(--font-display);
  font-size: clamp(21px, 4.4vw, 28px);
  font-weight: 600;
  line-height: 1.4;
  letter-spacing: .01em;
  color: var(--white);
}

.page-about .ch-lede {
  max-width: 36em;
  margin: 0 0 var(--s4);
  font-size: 16px;
  line-height: 1.85;
  color: var(--paper);
}

.page-about .section-more {
  margin: var(--s4) 0 0;
}

/* ---------- 图片 ---------- */

.page-about .about-figure {
  margin: 0 0 var(--s4);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--line-gold);
  background: var(--drawer);
  filter: saturate(.72) contrast(1.04);
}

.page-about .about-figure figcaption {
  margin-top: var(--s2);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--index);
}

/* ---------- 收录范围 ---------- */

.page-about .scope-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--line-grey);
  border: 1px solid var(--line-grey);
}

.page-about .scope-item {
  background: var(--drawer);
  padding: var(--s4) var(--s3);
  transition: background .22s var(--ease), transform .22s var(--ease);
}

.page-about .scope-item:hover {
  background: var(--drawer-2);
  transform: translateY(-2px);
}

.page-about .scope-item h3 {
  margin: var(--s2) 0 var(--s2);
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 600;
  line-height: 1.55;
  color: var(--white);
}

.page-about .scope-item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.82;
  color: var(--paper);
}

/* ---------- 版本时间线 ---------- */

.page-about .about-timeline {
  list-style: none;
  position: relative;
  margin: var(--s4) 0 0;
  padding: 0 0 0 32px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg, var(--gold) 0%, rgba(201, 162, 39, .28) 55%, rgba(201, 162, 39, .06) 100%);
}

.page-about .tl-item {
  position: relative;
  padding-bottom: var(--s5);
}

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

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -32px;
  top: 7px;
  width: 15px;
  height: 15px;
  border: 1px solid var(--gold);
  background: var(--ink);
  transition: background .22s var(--ease), box-shadow .22s var(--ease);
}

.page-about .tl-item:hover::before,
.page-about .tl-item:focus-within::before {
  background: var(--gold-hi);
  box-shadow: 0 0 0 4px rgba(201, 162, 39, .16);
}

.page-about .tl-ver {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: var(--s2);
  font-family: var(--font-mono);
  font-size: 19px;
  font-weight: 500;
  letter-spacing: .04em;
  color: var(--gold-hi);
  margin-bottom: 10px;
}

.page-about .tl-count {
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--cyan);
  border: 1px solid rgba(53, 224, 210, .34);
  padding: 2px 8px;
}

.page-about .tl-body {
  margin: 0;
  max-width: 34em;
  font-size: 15px;
  line-height: 1.85;
  color: var(--paper);
}

/* ---------- 编号示意 ---------- */

.page-about .num-figure {
  margin: 0 0 var(--s4);
  padding: var(--s3);
  background: var(--drawer);
  border: 1px solid var(--line-gold);
}

.page-about .num-figure svg {
  display: block;
  width: 100%;
  max-width: 720px;
  height: auto;
  margin: 0 auto;
}

.page-about .num-figure figcaption {
  margin-top: var(--s2);
  text-align: center;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--index);
}

/* ---------- 键值行 ---------- */

.page-about .kv-rows {
  border-top: 1px solid var(--line-grey);
}

.page-about .kv-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 6px;
  padding: var(--s3) 0;
  border-bottom: 1px solid var(--line-grey);
}

.page-about .kv-key {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--gold);
}

.page-about .kv-row p {
  margin: 0;
  max-width: 34em;
  font-size: 15px;
  line-height: 1.85;
  color: var(--paper);
}

.page-about .kv-example {
  margin: var(--s3) 0 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--paper);
  max-width: 36em;
}

.page-about code {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--cyan);
  background: rgba(53, 224, 210, .08);
  border: 1px solid rgba(53, 224, 210, .26);
  padding: 1px 6px;
  white-space: nowrap;
}

/* ---------- 上架流程 ---------- */

.page-about .flow {
  display: grid;
  gap: 1px;
  background: var(--line-gold);
  border: 1px solid var(--line-gold);
}

.page-about .flow-step {
  background: var(--drawer);
}

.page-about .flow-step > summary {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: center;
  gap: var(--s3);
  padding: var(--s3);
  cursor: pointer;
  list-style: none;
  transition: background .2s var(--ease);
}

.page-about .flow-step > summary::-webkit-details-marker {
  display: none;
}

.page-about .flow-step > summary:hover {
  background: var(--drawer-2);
}

.page-about .flow-step > summary:focus-visible {
  outline: 2px solid var(--gold-hi);
  outline-offset: -2px;
}

.page-about .flow-step[open] > summary {
  border-bottom: 1px solid var(--line-grey);
}

.page-about .flow-num {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: .08em;
  color: var(--cyan);
  border: 1px solid rgba(53, 224, 210, .4);
  padding: 3px 8px;
}

.page-about .flow-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 14px;
}

.page-about .flow-name {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 600;
  color: var(--white);
}

.page-about .flow-brief {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--index);
}

.page-about .flow-body {
  padding: var(--s3);
}

.page-about .flow-body p {
  margin: 0;
  max-width: 34em;
  font-size: 15px;
  line-height: 1.85;
  color: var(--paper);
}

/* ---------- 常设小组 ---------- */

.page-about .crew-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--s3);
}

.page-about .crew-list li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: var(--s3);
  align-items: start;
  padding: var(--s3);
  background: rgba(16, 42, 34, .72);
  border-left: 2px solid var(--gold);
}

.page-about .crew-num {
  font-family: var(--font-mono);
  font-size: 34px;
  font-weight: 500;
  line-height: 1;
  color: var(--gold-hi);
}

.page-about .crew-text strong {
  display: block;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 600;
  color: var(--white);
  margin-bottom: 8px;
}

.page-about .crew-text p {
  margin: 0;
  max-width: 32em;
  font-size: 15px;
  line-height: 1.82;
  color: var(--paper);
}

/* ---------- 勘误 ---------- */

.page-about .errata-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--s3);
  counter-reset: none;
}

.page-about .errata-steps li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: var(--s3);
  align-items: start;
}

.page-about .es-num {
  display: grid;
  place-items: center;
  width: 30px;
  height: 30px;
  border: 1px solid rgba(226, 81, 124, .5);
  background: rgba(226, 81, 124, .1);
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--rose);
  flex: none;
}

.page-about .errata-steps p {
  margin: 4px 0 0;
  max-width: 34em;
  font-size: 15px;
  line-height: 1.85;
  color: var(--paper);
}

.page-about .errata-foot {
  margin-top: var(--s4);
  padding: var(--s3);
  border: 1px solid rgba(226, 81, 124, .3);
  background: rgba(226, 81, 124, .06);
}

.page-about .errata-foot p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--paper);
  max-width: 38em;
}

.page-about .errata-foot p + p {
  margin-top: 8px;
}

.page-about .errata-foot a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 224, 210, .45);
}

.page-about .errata-foot a:hover,
.page-about .errata-foot a:focus-visible {
  color: var(--gold-hi);
  border-bottom-color: var(--gold-hi);
}

.page-about .section-more .btn {
  display: inline-block;
  text-decoration: none;
}

/* ---------- 响应式 ---------- */

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

  .page-about .kv-row {
    grid-template-columns: 168px minmax(0, 1fr);
    gap: var(--s3);
    align-items: baseline;
  }

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

@media (min-width: 1000px) {
  .page-about .about-layout {
    grid-template-columns: var(--rail-w) minmax(0, 1fr);
    gap: var(--col-gap);
  }

  .page-about .about-rail {
    display: block;
    align-self: start;
    position: sticky;
    top: calc(var(--header-h-solid) + var(--s3));
    max-height: calc(100vh - var(--header-h-solid) - var(--s4));
    overflow-y: auto;
    padding-left: var(--s3);
    border-left: 1px solid var(--line-gold);
  }

  .page-about .masthead-grid {
    grid-template-columns: minmax(0, 1fr) 300px;
    gap: var(--s5);
    align-items: end;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .scope-item,
  .page-about .tl-item::before,
  .page-about .index-link,
  .page-about .flow-step > summary {
    transition: none;
  }

  .page-about .scope-item:hover {
    transform: none;
  }
}
<<<END>>>