.page-about {
  --about-line: rgba(14, 27, 51, 0.14);
  --about-line-strong: rgba(14, 27, 51, 0.3);
  --about-soft: #DCD7CB;
  --about-gap: clamp(28px, 5.4vw, 76px);
  background: var(--cream);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.7;
  overflow-x: clip;
}

.page-about .about-shell {
  width: 100%;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 var(--edge) clamp(40px, 7vw, 96px);
}

.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-top: clamp(16px, 3vw, 32px);
  font-family: var(--mono);
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--graphite);
}

.page-about .breadcrumb a {
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--mist);
  padding-bottom: 1px;
}

.page-about .breadcrumb a:hover {
  border-bottom-color: var(--orange);
}

.page-about .breadcrumb__sep {
  color: var(--mist);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: clamp(20px, 3.6vw, 40px);
  align-items: end;
  margin-top: clamp(16px, 2.6vw, 26px);
  padding-top: clamp(18px, 3vw, 32px);
  border-top: 1px solid var(--about-line-strong);
}

.page-about .about-hero__inner {
  position: relative;
  background: var(--paper);
  border: 1px solid var(--about-line-strong);
  padding: clamp(22px, 4vw, 44px) clamp(20px, 3.4vw, 40px);
}

.page-about .about-hero__inner::before {
  content: "";
  position: absolute;
  top: -1px;
  left: -1px;
  width: 42px;
  height: 6px;
  background: var(--orange);
}

.page-about .about-hero__kicker {
  margin: 0 0 14px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--orange);
}

.page-about .about-hero h1 {
  margin: 0 0 18px;
  font-family: var(--serif);
  font-weight: 700;
  font-size: clamp(30px, 5.2vw, 54px);
  line-height: 1.16;
  letter-spacing: -0.02em;
}

.page-about .about-hero__lede {
  margin: 0;
  max-width: 34em;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--graphite);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(110px, 1fr));
  gap: 16px;
  margin: 24px 0 0;
  padding-top: 18px;
  border-top: 1px solid var(--about-line);
}

.page-about .about-hero__fact dt {
  font-size: 12.5px;
  color: var(--graphite);
  letter-spacing: 0.02em;
}

.page-about .about-hero__fact dd {
  margin: 4px 0 0;
  font-family: var(--mono);
  font-size: clamp(20px, 2.4vw, 26px);
  line-height: 1.2;
  color: var(--ink);
}

.page-about .about-hero__fact dd span {
  margin-left: 4px;
  font-family: var(--sans);
  font-size: 12.5px;
  color: var(--graphite);
}

.page-about .about-hero__figure {
  margin: 0;
  border: 1px solid var(--about-line-strong);
  background: var(--ink);
  overflow: hidden;
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
}

/* ---------- 章节索引 ---------- */
.page-about .about-toc {
  margin-top: clamp(28px, 4.6vw, 56px);
  border-top: 1px solid var(--about-line-strong);
  border-bottom: 1px solid var(--about-line-strong);
}

.page-about .about-toc__list {
  display: flex;
  gap: clamp(18px, 3vw, 40px);
  margin: 0;
  padding: 14px 2px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-toc__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  white-space: nowrap;
  font-size: 14px;
  color: var(--ink);
  text-decoration: none;
  transition: color 0.2s var(--ease);
}

.page-about .about-toc__link:hover,
.page-about .about-toc__link:focus-visible {
  color: var(--orange);
}

.page-about .about-toc__num {
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--orange);
}

/* ---------- 章节通用 ---------- */
.page-about .about-chapter {
  padding-top: clamp(40px, 6.6vw, 84px);
  --chap: var(--orange);
}

.page-about .about-chapter + .about-chapter {
  margin-top: clamp(32px, 5vw, 64px);
  border-top: 1px solid var(--about-line);
}

.page-about .about-chapter--2 { --chap: var(--lime); }
.page-about .about-chapter--3 { --chap: var(--amber); }
.page-about .about-chapter--4 { --chap: var(--teal); }
.page-about .about-chapter--5 { --chap: var(--rose); }

.page-about .about-chapter__head {
  display: grid;
  gap: 14px;
}

.page-about .about-chapter__num {
  display: block;
  font-family: var(--mono);
  font-size: clamp(38px, 6vw, 68px);
  line-height: 0.86;
  letter-spacing: -0.05em;
  color: var(--mist);
}

.page-about .about-chapter__num::after {
  content: "";
  display: block;
  width: 52px;
  height: 3px;
  margin-top: 16px;
  background: var(--chap);
}

.page-about .about-chapter__title {
  margin: 0 0 12px;
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(23px, 3.4vw, 38px);
  line-height: 1.24;
  letter-spacing: -0.015em;
}

.page-about .about-chapter__lede {
  margin: 0;
  max-width: 40em;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--graphite);
}

.page-about .about-chapter__lede a,
.page-about .about-chapter__more a {
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--orange);
}

.page-about .about-chapter__lede a:hover,
.page-about .about-chapter__more a:hover {
  color: var(--orange);
}

.page-about .about-chapter__more {
  margin: 22px 0 0;
  font-size: 14.5px;
  color: var(--graphite);
}

.page-about .about-body {
  display: grid;
  gap: clamp(22px, 3.4vw, 40px);
  margin-top: clamp(22px, 3.4vw, 36px);
}

/* ---------- 01 费用条目 ---------- */
.page-about .about-points {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-points li {
  padding: 18px 0;
  border-top: 1px solid var(--about-line);
}

.page-about .about-points li:first-child {
  padding-top: 0;
  border-top: 0;
}

.page-about .about-points__key {
  display: block;
  margin-bottom: 7px;
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.14em;
  color: var(--orange);
}

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

.page-about .about-note {
  align-self: start;
  background: var(--ink);
  color: var(--paper);
  padding: clamp(22px, 3.2vw, 32px);
}

.page-about .about-note__title {
  margin: 0 0 12px;
  font-family: var(--serif);
  font-size: 20px;
  font-weight: 600;
  line-height: 1.4;
}

.page-about .about-note p {
  margin: 0 0 20px;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--about-soft);
}

/* ---------- 按钮 ---------- */
.page-about .btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  font-family: var(--sans);
  font-size: 14px;
  line-height: 1.4;
  text-decoration: none;
  border: 1px solid var(--ink);
  background: transparent;
  color: var(--ink);
  transition: background 0.25s var(--ease), color 0.25s var(--ease), border-color 0.25s var(--ease);
}

.page-about .btn--primary {
  background: var(--orange);
  border-color: var(--orange);
  color: var(--ink);
  font-weight: 600;
}

.page-about .btn--primary:hover,
.page-about .btn--primary:focus-visible {
  background: var(--ink);
  border-color: var(--ink);
  color: var(--paper);
}

.page-about .btn--ghost {
  border-color: var(--mist);
  color: var(--paper);
}

.page-about .btn--ghost:hover,
.page-about .btn--ghost:focus-visible {
  border-color: var(--orange);
  color: var(--orange);
}

.page-about .btn:hover,
.page-about .btn:focus-visible {
  border-color: var(--orange);
}

/* ---------- 02 原则 ---------- */
.page-about .principles {
  display: grid;
  gap: 14px;
}

.page-about .principle {
  background: var(--paper);
  border: 1px solid var(--about-line);
  border-left: 8px solid var(--accent, var(--orange));
  padding: 20px 20px 22px;
  transition: transform 0.28s var(--ease), border-color 0.28s var(--ease);
}

.page-about .principle--orange { --accent: var(--orange); }
.page-about .principle--lime { --accent: var(--lime); }
.page-about .principle--rose { --accent: var(--rose); }

.page-about .principle:hover,
.page-about .principle:focus-visible {
  transform: translateY(-3px);
  border-color: var(--about-line-strong);
  outline: none;
}

.page-about .principle__index {
  margin: 0 0 8px;
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.14em;
  color: var(--graphite);
}

.page-about .principle__title {
  margin: 0 0 10px;
  font-family: var(--serif);
  font-size: 19px;
  font-weight: 600;
  line-height: 1.4;
}

.page-about .principle__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--graphite);
}

.page-about .principle__scene {
  display: block;
  margin: 12px 0 0;
  padding-top: 10px;
  border-top: 1px dashed var(--about-line);
  font-size: 13px;
  line-height: 1.7;
  color: var(--accent, var(--orange));
  opacity: 0;
  transform: translateY(-4px);
  transition: opacity 0.28s var(--ease), transform 0.28s var(--ease);
}

.page-about .principle:hover .principle__scene,
.page-about .principle:focus-visible .principle__scene {
  opacity: 1;
  transform: none;
}

.page-about .about-figure {
  margin: 0;
  align-self: start;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--about-line-strong);
  object-fit: cover;
}

.page-about .about-figure figcaption {
  margin-top: 12px;
  padding-left: 12px;
  border-left: 3px solid var(--lime);
  font-size: 13px;
  line-height: 1.7;
  color: var(--graphite);
}

/* ---------- 03 版本 ---------- */
.page-about .versions {
  display: grid;
  gap: 14px;
  margin-top: clamp(22px, 3.4vw, 36px);
}

.page-about .version {
  position: relative;
  background: var(--paper);
  border: 1px solid var(--about-line);
  border-top: 5px solid var(--vcolor, var(--mist));
  padding: 20px 18px 22px;
  transition: transform 0.28s var(--ease), border-color 0.28s var(--ease);
}

.page-about .version:hover {
  transform: translateY(-3px);
  border-color: var(--about-line-strong);
  border-top-color: var(--vcolor, var(--mist));
}

.page-about .version--ghost { --vcolor: var(--mist); }
.page-about .version--orange { --vcolor: var(--orange); }
.page-about .version--lime { --vcolor: var(--lime); }
.page-about .version--amber { --vcolor: var(--amber); }

.page-about .version__tag {
  display: inline-block;
  margin: 0 0 12px;
  padding: 3px 9px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--ink);
  background: var(--vcolor, var(--mist));
}

.page-about .version__name {
  margin: 0 0 10px;
  font-family: var(--serif);
  font-size: 18px;
  font-weight: 600;
  line-height: 1.4;
}

.page-about .version__text {
  margin: 0 0 12px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--graphite);
}

.page-about .version__fit {
  margin: 0;
  padding-top: 10px;
  border-top: 1px solid var(--about-line);
  font-size: 12.5px;
  letter-spacing: 0.02em;
  color: var(--ink-2);
}

.page-about .about-timeline {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 16px;
  margin: clamp(24px, 3.6vw, 40px) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-timeline li {
  position: relative;
  padding-top: 14px;
  border-top: 1px solid var(--about-line-strong);
  font-size: 13px;
  line-height: 1.7;
  color: var(--graphite);
}

.page-about .about-timeline li::before {
  content: "";
  position: absolute;
  top: -4px;
  left: 0;
  width: 7px;
  height: 7px;
  background: var(--amber);
}

.page-about .about-timeline__year {
  display: block;
  margin-bottom: 4px;
  font-family: var(--mono);
  font-size: 13px;
  color: var(--ink);
}

/* ---------- 04 落点 ---------- */
.page-about .about-map {
  position: relative;
  margin: 0;
  align-self: start;
}

.page-about .about-map img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--about-line-strong);
  object-fit: cover;
}

.page-about .about-map__badge {
  position: absolute;
  left: 12px;
  bottom: 52px;
  padding: 6px 11px;
  background: var(--ink);
  color: var(--paper);
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.04em;
  opacity: 0;
  transform: translateY(6px);
  transition: opacity 0.28s var(--ease), transform 0.28s var(--ease);
}

.page-about .about-map:hover .about-map__badge,
.page-about .about-map:focus-within .about-map__badge {
  opacity: 1;
  transform: none;
}

.page-about .about-map figcaption {
  margin-top: 12px;
  padding-left: 12px;
  border-left: 3px solid var(--teal);
  font-size: 13px;
  line-height: 1.7;
  color: var(--graphite);
}

.page-about .about-shop__text {
  margin: 0 0 4px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--graphite);
}

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 18px 16px;
  margin: 22px 0 0;
  padding-top: 18px;
  border-top: 1px solid var(--about-line-strong);
}

.page-about .about-stats dt {
  font-size: 12.5px;
  color: var(--graphite);
}

.page-about .about-stats dd {
  margin: 4px 0 0;
  font-family: var(--mono);
  font-size: 21px;
  line-height: 1.25;
  color: var(--ink);
}

.page-about .about-stats dd span {
  margin-left: 3px;
  font-family: var(--sans);
  font-size: 12px;
  color: var(--graphite);
}

.page-about .about-team {
  margin-top: 24px;
  padding: 18px 18px 20px;
  background: var(--paper);
  border: 1px solid var(--about-line);
}

.page-about .about-team__title {
  margin: 0 0 14px;
  font-family: var(--serif);
  font-size: 16px;
  font-weight: 600;
}

.page-about .about-team__list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 13px;
  color: var(--graphite);
}

.page-about .about-team__num {
  display: block;
  margin-bottom: 2px;
  font-family: var(--mono);
  font-size: 19px;
  color: var(--ink);
}

.page-about .about-contact {
  margin-top: 22px;
  padding-top: 18px;
  border-top: 1px solid var(--about-line);
}

.page-about .about-contact p {
  margin: 0 0 8px;
  font-family: var(--mono);
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--ink);
  word-break: break-all;
}

.page-about .about-contact__label {
  display: inline-block;
  min-width: 72px;
  margin-right: 8px;
  font-family: var(--sans);
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--graphite);
}

.page-about .about-contact .btn {
  margin-top: 10px;
}

/* ---------- 05 问答 ---------- */
.page-about .about-faq {
  margin-top: clamp(22px, 3.4vw, 36px);
  border-top: 2px solid var(--ink);
}

.page-about .about-faq details {
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-faq summary {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
  padding: 18px 0;
  cursor: pointer;
  list-style: none;
  transition: color 0.2s var(--ease);
}

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

.page-about .about-faq summary::after {
  content: "+";
  flex: 0 0 auto;
  font-family: var(--mono);
  font-size: 20px;
  line-height: 1.2;
  color: var(--rose);
  transition: transform 0.25s var(--ease);
}

.page-about .about-faq details[open] summary::after {
  transform: rotate(45deg);
}

.page-about .about-faq summary:hover {
  color: var(--rose);
}

.page-about .about-faq__q {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.6;
}

.page-about .about-faq__a {
  padding: 0 0 20px;
}

.page-about .about-faq__a p {
  margin: 0 0 12px;
  max-width: 46em;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--graphite);
}

.page-about .about-faq__link {
  display: inline-block;
  font-size: 13.5px;
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--rose);
  padding-bottom: 1px;
}

.page-about .about-faq__link:hover {
  color: var(--rose);
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  display: grid;
  gap: 20px;
  margin-top: var(--about-gap);
  padding: clamp(24px, 4vw, 44px);
  background: var(--ink);
  color: var(--paper);
  border-left: 10px solid var(--orange);
}

.page-about .about-cta__title {
  margin: 0 0 10px;
  font-family: var(--serif);
  font-size: clamp(21px, 3vw, 30px);
  font-weight: 600;
  line-height: 1.3;
}

.page-about .about-cta__text {
  margin: 0;
  max-width: 34em;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--about-soft);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (max-width: 899px) {
  .page-about .about-hero__figure {
    aspect-ratio: 4 / 3;
  }

  .page-about .about-hero__figure img {
    height: 100%;
    object-fit: cover;
  }

  .page-about .about-map__badge {
    opacity: 1;
    transform: none;
  }

  .page-about .principle__scene {
    opacity: 1;
    transform: none;
  }
}

@media (max-width: 640px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-contact__label {
    display: block;
    min-width: 0;
    margin: 0 0 2px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }

  .page-about .about-chapter__head {
    grid-template-columns: 132px minmax(0, 1fr);
    gap: clamp(20px, 3vw, 40px);
    align-items: start;
  }

  .page-about .about-chapter__num {
    position: sticky;
    top: 24px;
  }

  .page-about .about-body {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }

  .page-about .about-body--flip {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  }

  .page-about .about-body--flip .principles {
    order: 2;
  }

  .page-about .about-body--flip .about-figure {
    order: 1;
  }

  .page-about .about-figure {
    position: sticky;
    top: 24px;
  }

  .page-about .about-cta {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }
}

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

@media (min-width: 1060px) {
  .page-about .versions {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .principle,
  .page-about .version,
  .page-about .principle__scene,
  .page-about .about-map__badge,
  .page-about .btn,
  .page-about .about-faq summary::after {
    transition: none;
  }

  .page-about .principle:hover,
  .page-about .version:hover {
    transform: none;
  }
}
<<<END>>>