.page-about {
  --ab-col: 132px;
  background-color: var(--paper);
  color: var(--black);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.8;
  overflow-x: hidden;
  background-image:
    linear-gradient(rgba(228, 230, 226, 0.55) 1px, transparent 1px),
    linear-gradient(90deg, rgba(228, 230, 226, 0.55) 1px, transparent 1px);
  background-size: 56px 56px;
  background-position: -1px -1px;
}

.page-about .ab-crumb-bar {
  padding-top: clamp(16px, 3vw, 28px);
}

.page-about .ab-crumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--ink);
}

.page-about .ab-crumb .sk-crumb__link {
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--spark);
  padding-bottom: 1px;
}

.page-about .ab-crumb .sk-crumb__link:hover,
.page-about .ab-crumb .sk-crumb__link:focus-visible {
  border-bottom-color: var(--violet);
}

/* ---------- 首屏 ---------- */

.page-about .ab-hero {
  padding: clamp(22px, 4vw, 44px) 0 clamp(38px, 6vw, 72px);
}

.page-about .ab-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 4vw, 52px);
  align-items: end;
}

.page-about .ab-hero__figure {
  margin: 0;
}

.page-about .ab-hero__img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  border: 1px solid var(--line);
  background: var(--winter);
  object-fit: cover;
}

.page-about .ab-hero__cap {
  margin-top: 10px;
  display: block;
  color: var(--ink);
  opacity: 0.75;
}

.page-about .ab-h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2.05rem, 5.4vw, 4.1rem);
  line-height: 1.14;
  letter-spacing: -0.02em;
  color: var(--ink);
  overflow-wrap: break-word;
}

.page-about .ab-lead {
  margin: 20px 0 0;
  max-width: 48ch;
  font-size: clamp(1rem, 1.4vw, 1.1rem);
  line-height: 1.85;
  color: var(--black);
}

.page-about .ab-facts {
  display: flex;
  flex-wrap: wrap;
  margin: clamp(24px, 4vw, 36px) 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--ink);
}

.page-about .ab-facts li {
  flex: 1 1 150px;
  min-width: 0;
  padding: 14px 18px 14px 0;
  border-right: 1px solid var(--line);
}

.page-about .ab-facts li:last-child {
  border-right: 0;
}

.page-about .ab-facts__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.35rem, 2.5vw, 1.85rem);
  line-height: 1.25;
  letter-spacing: 0.02em;
  color: var(--ink);
}

.page-about .ab-facts__label {
  display: block;
  margin-top: 4px;
  font-family: var(--font-display);
  font-size: 12px;
  line-height: 1.5;
  letter-spacing: 0.04em;
  color: var(--black);
  opacity: 0.7;
}

/* ---------- 章节导航 ---------- */

.page-about .ab-toc {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: rgba(244, 241, 234, 0.82);
}

.page-about .ab-toc__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 20px;
  padding-top: 12px;
  padding-bottom: 12px;
}

.page-about .ab-toc__label {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--ink);
  opacity: 0.7;
}

.page-about .ab-toc__link {
  font-family: var(--font-display);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--ink);
  text-decoration: none;
  padding: 4px 0;
  border-bottom: 1px solid transparent;
}

.page-about .ab-toc__link:hover,
.page-about .ab-toc__link:focus-visible {
  border-bottom-color: var(--spark);
}

/* ---------- 章节骨架 ---------- */

.page-about .ab-chapter {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(12px, 2.4vw, 30px);
  padding: clamp(34px, 5.5vw, 70px) 0;
  border-bottom: 1px solid var(--line);
}

.page-about .ab-margin {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding-bottom: 10px;
  border-bottom: 1px dashed var(--line);
}

.page-about .ab-margin__no {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--ink);
}

.page-about .ab-margin__tag {
  margin: 0;
  font-family: var(--font-display);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--black);
}

.page-about .ab-margin__year {
  margin: 0 0 0 auto;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--ink);
  opacity: 0.8;
}

.page-about .ab-body p {
  margin: 0 0 16px;
  max-width: 64ch;
}

.page-about .ab-h2 {
  margin: 0 0 18px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.5rem, 3.1vw, 2.35rem);
  line-height: 1.28;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about .ab-h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.02rem;
  line-height: 1.45;
  letter-spacing: 0.01em;
  color: var(--ink);
}

.page-about .ab-link {
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--spark);
  padding-bottom: 2px;
  font-family: var(--font-display);
  font-size: 15px;
}

.page-about .ab-link:hover,
.page-about .ab-link:focus-visible {
  border-bottom-color: var(--violet);
  color: var(--violet);
}

.page-about .ab-inline-link {
  margin-top: 18px;
}

/* ---------- 起点章节 ---------- */

.page-about .ab-pull {
  margin-top: clamp(22px, 3vw, 32px);
  padding: clamp(18px, 2.6vw, 28px);
  border: 1px solid var(--line);
  border-top: 3px solid var(--spring);
  background: rgba(255, 255, 255, 0.62);
}

.page-about .ab-pull__k {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--ink);
  opacity: 0.75;
}

.page-about .ab-pull__v {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.5rem, 3vw, 2.1rem);
  line-height: 1.25;
  color: var(--ink);
}

.page-about .ab-pull__v small {
  display: block;
  margin-top: 4px;
  font-family: var(--font-body);
  font-weight: 400;
  font-size: 15px;
  letter-spacing: 0;
  color: var(--black);
  opacity: 0.8;
}

.page-about .ab-pull .sk-note {
  margin: 10px 0 0;
  color: var(--black);
  opacity: 0.75;
}

/* ---------- 四季色卡 ---------- */

.page-about .ab-seasons {
  margin-top: clamp(18px, 3vw, 28px);
}

.page-about .ab-seasons__radio {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  border: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
}

.page-about .ab-seasons__tabs {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
  margin-bottom: 14px;
}

.page-about .ab-seasons__tab {
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 11px 12px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.55);
  font-family: var(--font-display);
  font-size: 13.5px;
  line-height: 1.4;
  color: var(--ink);
  cursor: pointer;
  transition: border-color 180ms ease, background-color 180ms ease;
}

.page-about .ab-seasons__tab:hover {
  border-color: var(--ink);
}

.page-about .ab-seasons__swatch {
  flex: 0 0 auto;
  width: 15px;
  height: 15px;
  border: 1px solid var(--ink);
  background: var(--line);
}

.page-about .ab-seasons__tab[for="ab-season-spring"] .ab-seasons__swatch { background: var(--spring); }
.page-about .ab-seasons__tab[for="ab-season-summer"] .ab-seasons__swatch { background: var(--summer); }
.page-about .ab-seasons__tab[for="ab-season-autumn"] .ab-seasons__swatch { background: var(--autumn); }
.page-about .ab-seasons__tab[for="ab-season-winter"] .ab-seasons__swatch { background: var(--winter); }

.page-about .ab-seasons__radio:focus-visible + .ab-seasons__radio + .ab-seasons__radio + .ab-seasons__radio + .ab-seasons__tabs .ab-seasons__tab {
  outline: 2px solid var(--spark);
  outline-offset: 2px;
}

.page-about #ab-season-spring:checked ~ .ab-seasons__tabs [for="ab-season-spring"],
.page-about #ab-season-summer:checked ~ .ab-seasons__tabs [for="ab-season-summer"],
.page-about #ab-season-autumn:checked ~ .ab-seasons__tabs [for="ab-season-autumn"],
.page-about #ab-season-winter:checked ~ .ab-seasons__tabs [for="ab-season-winter"] {
  background: #fff;
  border-color: var(--ink);
}

.page-about #ab-season-spring:checked ~ .ab-seasons__tabs [for="ab-season-spring"] { box-shadow: inset 0 -3px 0 0 var(--spring); }
.page-about #ab-season-summer:checked ~ .ab-seasons__tabs [for="ab-season-summer"] { box-shadow: inset 0 -3px 0 0 var(--summer); }
.page-about #ab-season-autumn:checked ~ .ab-seasons__tabs [for="ab-season-autumn"] { box-shadow: inset 0 -3px 0 0 var(--autumn); }
.page-about #ab-season-winter:checked ~ .ab-seasons__tabs [for="ab-season-winter"] { box-shadow: inset 0 -3px 0 0 var(--winter); }

.page-about .ab-seasons__panels {
  border: 1px solid var(--ink);
  background: rgba(255, 255, 255, 0.72);
  padding: clamp(16px, 2.6vw, 26px);
}

.page-about .ab-seasons__panel {
  display: none;
}

.page-about #ab-season-spring:checked ~ .ab-seasons__panels .ab-seasons__panel[data-season="spring"],
.page-about #ab-season-summer:checked ~ .ab-seasons__panels .ab-seasons__panel[data-season="summer"],
.page-about #ab-season-autumn:checked ~ .ab-seasons__panels .ab-seasons__panel[data-season="autumn"],
.page-about #ab-season-winter:checked ~ .ab-seasons__panels .ab-seasons__panel[data-season="winter"] {
  display: block;
}

.page-about .ab-points {
  margin: 12px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 8px;
}

.page-about .ab-points li {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 8px;
  align-items: baseline;
  padding-top: 8px;
  border-top: 1px solid var(--line);
  font-size: 15px;
  line-height: 1.65;
}

.page-about .ab-points .sk-mono {
  font-size: 12px;
  color: var(--ink);
  opacity: 0.7;
}

/* ---------- 编辑桌 ---------- */

.page-about .ab-desk {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(18px, 3vw, 30px);
  align-items: start;
  margin-bottom: 8px;
}

.page-about .ab-figure {
  margin: 0;
}

.page-about .ab-figure__img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--line);
  background: var(--winter);
  object-fit: cover;
}

.page-about .ab-figure__img + .sk-note {
  display: block;
  margin-top: 10px;
  color: var(--ink);
  opacity: 0.72;
}

.page-about .ab-entries {
  margin: clamp(20px, 3vw, 30px) 0 20px;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .ab-entries__item {
  padding: 16px 18px;
  background: rgba(255, 255, 255, 0.7);
}

.page-about .ab-entries__no {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--autumn);
  margin-bottom: 4px;
}

.page-about .ab-entries__item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
}

.page-about .ab-quote {
  margin: clamp(24px, 3.4vw, 36px) 0;
  padding: 4px 0 4px 18px;
  border-left: 4px solid var(--spark);
}

.page-about .ab-quote p {
  margin: 0;
  max-width: 30ch;
  font-family: var(--font-body);
  font-size: clamp(1.2rem, 2.4vw, 1.7rem);
  line-height: 1.6;
  color: var(--ink);
}

/* ---------- 版本时间轴 ---------- */

.page-about .ab-version-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 34px);
  align-items: start;
  margin-top: 8px;
}

.page-about .ab-timeline {
  position: relative;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 16px;
  bottom: 16px;
  width: 1px;
  background: var(--line);
}

.page-about .ab-timeline__item {
  position: relative;
  padding-left: 32px;
  margin-bottom: 10px;
}

.page-about .ab-timeline__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 17px;
  width: 15px;
  height: 15px;
  border: 1px solid var(--ink);
  background: var(--paper);
  z-index: 1;
}

.page-about .ab-tl {
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.6);
}

.page-about .ab-tl[open] {
  border-color: var(--ink);
  background: #fff;
}

.page-about .ab-tl__summary {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 12px 14px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
}

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

.page-about .ab-tl__year {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--ink);
}

.page-about .ab-tl__name {
  font-size: 15px;
  line-height: 1.5;
  color: var(--black);
}

.page-about .ab-tl__mark {
  position: relative;
  flex: 0 0 auto;
  margin-left: auto;
  width: 12px;
  height: 12px;
  align-self: center;
}

.page-about .ab-tl__mark::before,
.page-about .ab-tl__mark::after {
  content: "";
  position: absolute;
  background: var(--ink);
}

.page-about .ab-tl__mark::before {
  left: 0;
  top: 5px;
  width: 12px;
  height: 2px;
}

.page-about .ab-tl__mark::after {
  left: 5px;
  top: 0;
  width: 2px;
  height: 12px;
  transition: transform 200ms ease;
}

.page-about .ab-tl[open] .ab-tl__mark::after {
  transform: scaleY(0);
}

.page-about .ab-tl__panel {
  padding: 0 14px 14px;
  border-top: 1px solid var(--line);
}

.page-about .ab-tl__panel p {
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.75;
  max-width: 56ch;
}

/* ---------- 团队与合作 ---------- */

.page-about .ab-team {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  margin-top: 8px;
}

.page-about .ab-team__card {
  padding: 18px 18px 20px;
  background: rgba(255, 255, 255, 0.72);
}

.page-about .ab-team__card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
}

.page-about .ab-team__chip {
  display: block;
  width: 26px;
  height: 5px;
  margin-bottom: 12px;
}

.page-about .ab-chip--spring { background: var(--spring); }
.page-about .ab-chip--summer { background: var(--summer); }
.page-about .ab-chip--autumn { background: var(--autumn); }
.page-about .ab-chip--winter { background: var(--winter); }

.page-about .ab-partners {
  margin-top: clamp(24px, 3.6vw, 40px);
  padding: clamp(18px, 3vw, 30px);
  border: 1px solid var(--line);
  border-left: 4px solid var(--violet);
  background: rgba(255, 255, 255, 0.62);
}

.page-about .ab-partners__k {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--violet);
}

.page-about .ab-partners__lede {
  margin: 0 0 14px;
  max-width: 60ch;
}

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

.page-about .ab-partners__list li {
  padding-top: 8px;
  border-top: 1px solid var(--line);
  font-size: 15px;
  line-height: 1.7;
}

/* ---------- 页尾行动区 ---------- */

.page-about .ab-cta {
  padding: clamp(34px, 5.5vw, 64px) 0 clamp(40px, 6vw, 72px);
}

.page-about .ab-cta__inner {
  display: grid;
  gap: 16px;
}

.page-about .ab-cta__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.4rem, 3vw, 2.1rem);
  line-height: 1.3;
  color: var(--ink);
}

.page-about .ab-cta__text {
  margin: 0;
  max-width: 58ch;
  font-size: 16px;
}

.page-about .ab-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 6px;
}

.page-about .ab-cta__links .sk-btn {
  text-decoration: none;
}

/* ---------- 响应式 ---------- */

@media (min-width: 620px) {
  .page-about .ab-seasons__tabs {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

@media (min-width: 880px) {
  .page-about .ab-hero__grid {
    grid-template-columns: minmax(0, 300px) minmax(0, 1fr);
  }

  .page-about .ab-desk {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.85fr);
  }

  .page-about .ab-version-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.62fr);
  }

  .page-about .ab-figure--version {
    position: sticky;
    top: 96px;
  }
}

@media (min-width: 900px) {
  .page-about .ab-chapter {
    grid-template-columns: var(--ab-col) minmax(0, 1fr);
    gap: clamp(24px, 3.4vw, 44px);
  }

  .page-about .ab-margin {
    display: block;
    position: sticky;
    top: 96px;
    align-self: start;
    padding: 0 0 0 16px;
    border-bottom: 0;
  }

  .page-about .ab-margin::before {
    content: "";
    position: absolute;
    left: 0;
    top: 3px;
    width: 4px;
    height: 40px;
    background: var(--ink);
  }

  .page-about .ab-chapter--origin .ab-margin::before { background: var(--spring); }
  .page-about .ab-chapter--seasons .ab-margin::before { background: var(--summer); }
  .page-about .ab-chapter--desk .ab-margin::before { background: var(--autumn); }
  .page-about .ab-chapter--versions .ab-margin::before { background: var(--winter); }
  .page-about .ab-chapter--people .ab-margin::before { background: var(--violet); }

  .page-about .ab-margin__no {
    display: block;
    font-size: 22px;
    line-height: 1.2;
  }

  .page-about .ab-margin__tag {
    display: block;
    margin-top: 12px;
  }

  .page-about .ab-margin__year {
    display: block;
    margin: 4px 0 0;
  }
}

@media (min-width: 1040px) {
  .page-about .ab-team {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-seasons__tab,
  .page-about .ab-tl__mark::after {
    transition: none;
  }
}
<<<END>>>