.page-about {
  --about-ink-line: rgba(23, 26, 31, .14);
  --about-ink-line-soft: rgba(23, 26, 31, .08);
  --about-snow-line: rgba(242, 246, 251, .16);
  background: var(--paper);
  color: var(--text);
  font-family: var(--font-body);
  padding-bottom: 84px;
}

.page-about a:focus-visible {
  outline: 2px solid var(--flag-yellow);
  outline-offset: 3px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: 20px 0 54px;
  color: var(--snow);
  background:
    radial-gradient(115% 85% at 82% -10%, rgba(47, 111, 181, .44) 0%, rgba(47, 111, 181, 0) 62%),
    linear-gradient(178deg, var(--ink-900) 0%, #0d2038 60%, var(--ink-800) 100%);
}

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

.page-about .about-crumb {
  margin: 0;
  font-size: 13px;
}

.page-about .about-crumb .arc-breadcrumb__link {
  color: rgba(242, 246, 251, .72);
  text-decoration: none;
  transition: color .18s ease;
}

.page-about .about-crumb .arc-breadcrumb__link:hover {
  color: var(--flag-yellow);
}

.page-about .about-crumb .arc-breadcrumb__sep {
  color: rgba(242, 246, 251, .38);
  margin: 0 8px;
}

.page-about .about-crumb__current {
  color: var(--snow);
  letter-spacing: .04em;
}

.page-about .about-hero__overline {
  margin: 0;
  color: var(--flag-yellow);
}

.page-about .about-hero__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2rem, 5.2vw, 4rem);
  line-height: 1.08;
  letter-spacing: .045em;
  color: var(--snow);
  text-wrap: balance;
}

.page-about .about-hero__lead {
  display: grid;
  gap: 14px;
  font-family: var(--font-editorial);
}

.page-about .about-hero__lead p {
  margin: 0;
  font-size: 17px;
  line-height: 1.85;
  color: rgba(242, 246, 251, .84);
}

.page-about .about-hero__lead p:first-child {
  font-size: 18px;
}

.page-about .about-hero__keys {
  list-style: none;
  margin: 6px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .about-hero__key {
  padding: 14px 16px;
  border: 1px solid var(--about-snow-line);
  border-radius: var(--radius-md);
  background: rgba(18, 41, 74, .52);
}

.page-about .about-hero__key b {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 22px;
  font-weight: 600;
  letter-spacing: .01em;
  color: var(--flag-yellow);
}

.page-about .about-hero__key span {
  display: block;
  margin-top: 7px;
  font-size: 13px;
  line-height: 1.55;
  letter-spacing: .02em;
  color: rgba(242, 246, 251, .72);
}

/* ---------- 横幅 ---------- */
.page-about .about-banner__strip {
  display: block;
  height: 6px;
  margin: 26px 0 0;
  border-radius: var(--radius-pill);
  background: linear-gradient(90deg,
    var(--flag-blue) 0 26%,
    var(--flag-white) 26% 40%,
    var(--flag-red) 40% 58%,
    var(--flag-green) 58% 76%,
    var(--flag-yellow) 76% 100%);
}

.page-about .about-banner {
  margin: 14px 0 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
}

/* ---------- 正文骨架 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
  padding-top: 46px;
}

.page-about .about-spy {
  border-top: 2px solid var(--flag-yellow);
  padding-top: 14px;
}

.page-about .about-spy__title {
  margin: 0 0 12px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .16em;
  color: var(--muted);
}

.page-about .about-spy .arc-spy__list {
  list-style: none;
  margin: 0;
  padding: 0 0 6px;
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: max-content;
  gap: 10px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-spy .arc-spy__link {
  display: block;
  padding: 6px 12px;
  border: 1px solid var(--about-ink-line);
  border-radius: var(--radius-pill);
  font-size: 13px;
  line-height: 1.4;
  color: var(--muted);
  text-decoration: none;
  white-space: nowrap;
  transition: color .18s ease, border-color .18s ease, background .18s ease;
}

.page-about .about-spy .arc-spy__link:hover,
.page-about .about-spy .arc-spy__link:focus-visible {
  color: var(--flag-blue);
  border-color: var(--flag-blue);
}

.page-about .about-spy .arc-spy__link[data-active],
.page-about .about-spy .arc-spy__link.is-active {
  color: var(--text);
  font-weight: 600;
  border-color: var(--flag-yellow);
  background: rgba(226, 168, 30, .12);
}

.page-about .about-flow {
  display: grid;
  gap: 20px;
  min-width: 0;
}

/* ---------- 章节卡 ---------- */
.page-about .about-chapter {
  position: relative;
  padding: 30px 22px 32px;
  border: 1px solid var(--about-ink-line-soft);
  border-radius: var(--radius-lg);
  background: var(--paper-card);
  box-shadow: 0 22px 44px -38px rgba(10, 26, 47, .7);
}

.page-about .about-chapter__title {
  margin: 10px 0 18px;
  font-family: var(--font-editorial);
  font-weight: 600;
  font-size: clamp(1.35rem, 2.6vw, 1.95rem);
  line-height: 1.36;
  letter-spacing: .02em;
  color: var(--text);
}

.page-about .about-chapter .arc-overline {
  margin: 0;
  color: var(--flag-blue);
}

.page-about .about-chapter__prose {
  max-width: var(--measure);
}

.page-about .about-chapter__prose p {
  margin: 0 0 1.15em;
  font-size: 17px;
  line-height: 1.85;
  color: var(--text);
}

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

.page-about .about-chapter--ink {
  color: var(--snow);
  border-color: var(--about-snow-line);
  background:
    radial-gradient(110% 90% at 88% 0%, rgba(47, 111, 181, .32) 0%, rgba(47, 111, 181, 0) 60%),
    linear-gradient(165deg, var(--ink-800) 0%, var(--ink-900) 80%);
  box-shadow: var(--shadow-float);
}

.page-about .about-chapter--ink .about-chapter__title {
  color: var(--snow);
}

.page-about .about-chapter--ink .arc-overline {
  color: var(--flag-yellow);
}

.page-about .about-chapter--ink .about-chapter__prose p {
  color: rgba(242, 246, 251, .84);
}

/* ---------- 证据边界 ---------- */
.page-about .about-note {
  margin-top: 24px;
  max-width: var(--measure);
  padding: 16px 18px;
  border-left: 3px solid var(--flag-blue);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: var(--paper-2);
}

.page-about .about-note__label {
  margin: 0 0 6px;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .16em;
  color: var(--flag-blue);
}

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

/* ---------- 四道工序 ---------- */
.page-about .about-steps__line {
  display: none;
}

.page-about .about-steps {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 24px;
}

.page-about .about-step {
  position: relative;
  padding: 34px 16px 6px;
  border: 1px solid var(--about-snow-line);
  border-radius: var(--radius-md);
  background: rgba(10, 26, 47, .52);
}

.page-about .about-step__head {
  display: flex;
  align-items: center;
  gap: 10px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-step__head::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 16px;
  line-height: 1;
  color: var(--flag-yellow);
  transition: transform .22s ease;
}

.page-about .about-step[open] .about-step__head::after {
  transform: rotate(45deg);
}

.page-about .about-step__dot {
  position: absolute;
  top: 13px;
  left: 16px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--flag-yellow);
  box-shadow: 0 0 0 5px rgba(226, 168, 30, .16);
}

.page-about .about-step__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--flag-yellow);
}

.page-about .about-step__name {
  font-size: 15px;
  font-weight: 600;
  letter-spacing: .02em;
  color: var(--snow);
}

.page-about .about-step__body {
  padding: 12px 0 12px;
}

.page-about .about-step__body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(242, 246, 251, .8);
}

.page-about .about-process__figure {
  margin: 28px 0 0;
  border-radius: var(--radius-md);
  overflow: hidden;
}

/* ---------- 版本演进 ---------- */
.page-about .about-versions {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
  margin-top: 6px;
}

.page-about .about-timeline {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 26px;
  display: grid;
  gap: 14px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--flag-yellow) 0%, rgba(226, 168, 30, .18) 100%);
}

.page-about .about-node {
  position: relative;
}

.page-about .about-node::before {
  content: "";
  position: absolute;
  top: 16px;
  left: -28px;
  box-sizing: content-box;
  width: 14px;
  height: 14px;
  border: 3px solid var(--paper-card);
  border-radius: 50%;
  background: var(--flag-yellow);
}

.page-about .about-node__box {
  padding: 14px 18px;
  border: 1px solid var(--about-ink-line-soft);
  border-radius: var(--radius-md);
  background: var(--paper-2);
}

.page-about .about-node__head {
  display: flex;
  flex-direction: column;
  gap: 6px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-node__line {
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.page-about .about-node__ver {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: .04em;
  color: var(--flag-blue);
}

.page-about .about-node__era {
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--muted);
}

.page-about .about-node__title {
  font-family: var(--font-editorial);
  font-size: 17px;
  font-weight: 600;
  line-height: 1.45;
  color: var(--text);
}

.page-about .about-node__body {
  padding-top: 12px;
}

.page-about .about-node__text {
  margin: 0 0 10px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text);
}

.page-about .about-node__meta {
  margin: 0;
  padding-top: 9px;
  border-top: 1px dashed var(--about-ink-line);
  font-size: 12.5px;
  line-height: 1.7;
  letter-spacing: .05em;
  color: var(--muted);
}

.page-about .about-term {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 10px;
  margin: 0 0 12px;
  padding: 9px 12px;
  border-left: 2px solid var(--flag-yellow);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: rgba(47, 111, 181, .1);
}

.page-about .about-term__key {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .06em;
  color: var(--flag-blue);
}

.page-about .about-term__val {
  flex: 1 1 12em;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .about-versions__figure {
  margin: 0;
  border-radius: var(--radius-md);
  overflow: hidden;
}

/* ---------- 团队 ---------- */
.page-about .about-team__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
  margin-top: 20px;
}

.page-about .about-team__block {
  padding: 20px 22px;
  border: 1px solid var(--about-ink-line-soft);
  border-radius: var(--radius-md);
  background: var(--paper-2);
}

.page-about .about-team__head {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: .06em;
  color: var(--text);
}

.page-about .about-team__block p {
  margin: 0 0 .9em;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text);
}

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

.page-about .about-cadence {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  display: grid;
  gap: 8px;
}

.page-about .about-cadence li {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding-bottom: 8px;
  border-bottom: 1px dashed var(--about-ink-line);
  font-size: 14px;
}

.page-about .about-cadence li:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}

.page-about .about-cadence__when {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: .04em;
  color: var(--flag-blue);
}

.page-about .about-cadence__what {
  color: var(--text);
}

/* ---------- 不做的事 ---------- */
.page-about .about-boundary {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  border: 1px solid var(--about-snow-line);
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--about-snow-line);
}

.page-about .about-boundary__item {
  display: flex;
  gap: 14px;
  padding: 18px 20px;
  background: rgba(10, 26, 47, .6);
}

.page-about .about-boundary__mark {
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  width: 22px;
  height: 22px;
  margin-top: 2px;
  border-radius: 50%;
  background: rgba(196, 58, 46, .22);
  color: #EB6A5C;
  font-size: 14px;
  line-height: 1;
}

.page-about .about-boundary__title {
  margin: 0 0 5px;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: .02em;
  color: var(--snow);
}

.page-about .about-boundary__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: rgba(242, 246, 251, .74);
}

/* ---------- 数据入口 ---------- */
.page-about .about-entry {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
}

.page-about .about-entry__link {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 16px 20px;
  border: 1px solid var(--about-ink-line);
  border-radius: var(--radius-md);
  background: var(--paper-2);
  color: var(--text);
  text-decoration: none;
  transition: border-color .18s ease, background .18s ease, transform .18s ease;
}

.page-about .about-entry__link:hover,
.page-about .about-entry__link:focus-visible {
  border-color: var(--flag-blue);
  background: #EFE7D6;
  transform: translateY(-2px);
}

.page-about .about-entry__name {
  font-family: var(--font-editorial);
  font-size: 17px;
  font-weight: 600;
  letter-spacing: .02em;
}

.page-about .about-entry__desc {
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

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

@media (min-width: 860px) {
  .page-about .about-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }

  .page-about .about-team__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
  }

  .page-about .about-entry {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
  }

  .page-about .about-boundary__item {
    padding: 20px 24px;
  }
}

@media (min-width: 1040px) {
  .page-about .about-hero {
    padding: 26px 0 66px;
  }

  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    column-gap: 56px;
    row-gap: 20px;
  }

  .page-about .about-crumb {
    grid-column: 1 / -1;
    grid-row: 1;
  }

  .page-about .about-hero__overline {
    grid-column: 1;
    grid-row: 2;
    align-self: end;
  }

  .page-about .about-hero__title {
    grid-column: 1;
    grid-row: 3;
    align-self: start;
  }

  .page-about .about-hero__lead {
    grid-column: 2;
    grid-row: 2 / span 2;
    align-self: end;
    padding-bottom: 6px;
  }

  .page-about .about-hero__keys {
    grid-column: 1 / -1;
    grid-row: 4;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    margin-top: 16px;
  }
}

@media (min-width: 1080px) {
  .page-about .about-body {
    grid-template-columns: 200px minmax(0, 1fr);
    column-gap: 56px;
    padding-top: 56px;
  }

  .page-about .about-spy {
    position: sticky;
    top: 104px;
    align-self: start;
    border-top: 0;
    border-left: 2px solid var(--flag-yellow);
    padding: 4px 0 0 16px;
  }

  .page-about .about-spy .arc-spy__list {
    grid-auto-flow: row;
    grid-auto-columns: auto;
    gap: 6px;
    overflow: visible;
  }

  .page-about .about-spy .arc-spy__link {
    padding: 5px 0;
    border: 0;
    border-bottom: 1px solid transparent;
    border-radius: 0;
    font-size: 14px;
    white-space: normal;
  }

  .page-about .about-spy .arc-spy__link:hover,
  .page-about .about-spy .arc-spy__link:focus-visible {
    border-bottom-color: var(--flag-blue);
  }

  .page-about .about-spy .arc-spy__link[data-active],
  .page-about .about-spy .arc-spy__link.is-active {
    background: transparent;
    border-bottom-color: var(--flag-yellow);
  }

  .page-about .about-chapter {
    padding: 40px 42px 44px;
  }

  .page-about .about-steps__line {
    display: block;
    width: 100%;
    height: 40px;
    margin: 18px 0 -4px;
  }

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

  .page-about .about-process__figure {
    width: 58%;
    margin-left: auto;
  }

  .page-about .about-versions {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    column-gap: 36px;
    align-items: start;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-entry__link,
  .page-about .about-step__head::after,
  .page-about .about-spy .arc-spy__link {
    transition: none;
  }

  .page-about .about-entry__link:hover,
  .page-about .about-entry__link:focus-visible {
    transform: none;
  }
}
<<<END>>>