.page-about {
  background: var(--paper-50);
  color: var(--text-900);
  font-family: var(--font-body);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background: var(--ink-900);
  color: var(--paper-50);
  padding-top: clamp(22px, 3.6vw, 38px);
  padding-bottom: clamp(46px, 7vw, 88px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(to right, rgba(201, 162, 39, 0.10) 0 1px, transparent 1px 96px),
    repeating-linear-gradient(to bottom, rgba(201, 162, 39, 0.07) 0 1px, transparent 1px 96px);
}

.page-about .about-hero .container {
  position: relative;
  z-index: 1;
}

.page-about .about-hero .breadcrumb {
  margin-bottom: clamp(26px, 4.5vw, 54px);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(30px, 4.5vw, 56px);
  align-items: end;
}

@media (min-width: 980px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.55fr) minmax(280px, 0.85fr);
  }
}

.page-about .about-hero__kicker {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--gold-500);
}

.page-about .about-hero__title {
  margin: 0 0 24px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(34px, 6.4vw, 76px);
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: var(--paper-50);
}

.page-about .about-hero__desc {
  max-width: 36em;
  margin: 0 0 30px;
  font-size: clamp(15px, 1.4vw, 17px);
  line-height: 1.85;
  color: rgba(250, 247, 242, 0.78);
}

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

.page-about .about-hero__index {
  border: 1px solid rgba(201, 162, 39, 0.5);
  background: rgba(28, 28, 26, 0.72);
  padding: 20px 18px 16px;
}

.page-about .about-index__title {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--gold-500);
}

.page-about .about-index__list {
  margin: 0;
}

.page-about .about-index__row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 14px;
  padding: 9px 0;
  border-top: 1px solid rgba(201, 162, 39, 0.22);
}

.page-about .about-index__row:first-child {
  border-top: 0;
}

.page-about .about-index__key,
.page-about .about-index__val {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
}

.page-about .about-index__key {
  color: rgba(250, 247, 242, 0.6);
}

.page-about .about-index__val {
  color: var(--gold-300);
  text-align: right;
}

/* ---------- 主体骨架 ---------- */
.page-about .about-body {
  display: grid;
  gap: clamp(30px, 4.5vw, 56px);
  padding-top: clamp(42px, 6vw, 88px);
  padding-bottom: clamp(46px, 7vw, 96px);
}

@media (min-width: 1040px) {
  .page-about .about-body {
    grid-template-columns: minmax(0, 1fr) 212px;
    align-items: start;
  }
}

/* ---------- 旁注索引 ---------- */
.page-about .about-rail {
  display: none;
}

@media (min-width: 1040px) {
  .page-about .about-rail {
    display: block;
    position: sticky;
    top: calc(var(--status-h) + 28px);
  }
}

.page-about .about-rail__label {
  margin: 0 0 12px;
  padding-left: 14px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--muted-600);
}

.page-about .about-rail__link {
  position: relative;
  display: block;
  padding: 8px 0 8px 14px;
  border-left: 1px solid var(--line-300);
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.55;
  letter-spacing: 0.04em;
  color: var(--muted-600);
  text-decoration: none;
  transition: color 0.18s ease, border-color 0.18s ease;
}

.page-about .about-rail__link::before {
  content: "";
  position: absolute;
  left: -2px;
  top: 50%;
  width: 4px;
  height: 16px;
  margin-top: -8px;
  background: var(--amber-600);
  opacity: 0;
  transition: opacity 0.18s ease;
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--gold-700);
  border-left-color: var(--gold-500);
}

.page-about .about-rail__link:hover::before,
.page-about .about-rail__link:focus-visible::before {
  opacity: 1;
}

/* ---------- 小节骨架 ---------- */
.page-about .about-section {
  margin-top: clamp(32px, 4.2vw, 56px);
  padding-top: clamp(32px, 4.2vw, 56px);
  border-top: 1px solid var(--line-300);
  scroll-margin-top: calc(var(--status-h) + 24px);
}

.page-about .about-section:first-child {
  margin-top: 0;
  padding-top: 0;
  border-top: 0;
}

.page-about .about-section__num {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--gold-700);
}

.page-about .about-section__title {
  position: relative;
  margin: 0 0 20px;
  padding-left: 20px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(23px, 3.2vw, 36px);
  line-height: 1.22;
  letter-spacing: -0.01em;
  color: var(--text-900);
}

.page-about .about-section__title::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.34em;
  width: 1px;
  height: 24px;
  background: var(--gold-500);
}

.page-about .about-text {
  max-width: 36em;
  margin: 0 0 18px;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--text-900);
}

.page-about .about-text--spaced {
  margin-top: 26px;
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 0 0 clamp(22px, 3vw, 34px);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--line-300);
  object-fit: cover;
}

.page-about .about-figure figcaption {
  margin-top: 10px;
  padding-left: 12px;
  border-left: 1px solid var(--gold-500);
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted-600);
}

.page-about .about-figure--side {
  margin-bottom: 0;
}

/* ---------- 四象限 ---------- */
.page-about .quad {
  display: grid;
  gap: 1px;
  margin-top: 8px;
  border: 1px solid var(--line-300);
  background: var(--line-300);
}

@media (min-width: 720px) {
  .page-about .quad {
    grid-template-columns: 1fr 1fr;
  }
}

.page-about .quad__cell {
  background: var(--paper-50);
  padding: 24px 22px 22px;
  transition: opacity 0.2s ease, background-color 0.2s ease;
}

@media (hover: hover) and (pointer: fine) {
  .page-about .quad:hover .quad__cell {
    opacity: 0.4;
  }

  .page-about .quad .quad__cell:hover {
    opacity: 1;
    background: var(--sand-100);
  }
}

.page-about .quad__index {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--gold-700);
}

.page-about .quad__name {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 800;
  color: var(--text-900);
}

.page-about .quad__desc {
  margin: 0 0 14px;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-900);
}

.page-about .quad__link {
  display: inline-block;
  padding-bottom: 2px;
  border-bottom: 1px solid var(--gold-500);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--gold-700);
  text-decoration: none;
  transition: color 0.18s ease;
}

.page-about .quad__link:hover,
.page-about .quad__link:focus-visible {
  color: var(--amber-600);
}

/* ---------- 版本时间轴 ---------- */
.page-about .timeline {
  position: relative;
  margin: 26px 0 0;
  padding: 0 0 0 26px;
  list-style: none;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--gold-500);
}

.page-about .timeline__item {
  position: relative;
  padding: 0 0 26px;
}

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

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 3px;
  width: 11px;
  height: 11px;
  box-sizing: border-box;
  background: var(--paper-50);
  border: 1px solid var(--gold-500);
}

.page-about .timeline__item--major::before {
  background: var(--gold-500);
}

.page-about .timeline__item--alert::before {
  background: var(--amber-600);
  border-color: var(--amber-600);
}

.page-about .timeline__when {
  display: block;
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--gold-700);
}

.page-about .timeline__what {
  margin: 0 0 6px;
  font-size: 15.5px;
  font-weight: 700;
  color: var(--text-900);
}

.page-about .timeline__desc {
  max-width: 30em;
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--muted-600);
}

@media (min-width: 900px) {
  .page-about .timeline {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0 clamp(12px, 2vw, 28px);
    padding-left: 0;
  }

  .page-about .timeline::before {
    left: 0;
    right: 0;
    top: 5px;
    bottom: auto;
    width: auto;
    height: 1px;
  }

  .page-about .timeline__item {
    padding: 30px 0 0;
  }

  .page-about .timeline__item::before {
    left: 0;
    top: 0;
  }
}

/* ---------- 分类维度 ---------- */
.page-about .about-taxsvg {
  display: block;
  width: 100%;
  max-width: 420px;
  height: auto;
  margin: 0 0 26px;
  padding: 12px;
  box-sizing: border-box;
  background: var(--sand-100);
  border: 1px solid var(--line-300);
}

.page-about .tagtri {
  display: grid;
  gap: 24px;
}

@media (min-width: 720px) {
  .page-about .tagtri {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
  }
}

.page-about .tagtri__col {
  padding-top: 14px;
  border-top: 2px solid var(--steel-500);
}

.page-about .tagtri__col:nth-child(2) {
  border-top-color: var(--gold-700);
}

.page-about .tagtri__col:nth-child(3) {
  border-top-color: var(--gold-500);
}

.page-about .tagtri__title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--muted-600);
}

.page-about .tagtri__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .tagtri__list li {
  padding: 5px 10px;
  border: 1px solid var(--line-300);
  background: var(--sand-100);
  font-size: 13px;
  line-height: 1.6;
  color: var(--text-900);
}

/* ---------- 视觉体系 ---------- */
.page-about .visual-split {
  display: grid;
  gap: clamp(24px, 3vw, 40px);
}

@media (min-width: 820px) {
  .page-about .visual-split {
    grid-template-columns: minmax(0, 1fr) minmax(240px, 330px);
    align-items: start;
  }
}

/* ---------- 内容流程 ---------- */
.page-about .flow {
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .flow__step {
  position: relative;
  padding: 0 0 30px 60px;
}

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

.page-about .flow__step::after {
  content: "";
  position: absolute;
  left: 19px;
  top: 46px;
  bottom: 0;
  width: 1px;
  background: var(--line-300);
}

.page-about .flow__step:last-child::after {
  display: none;
}

.page-about .flow__num {
  position: absolute;
  left: 0;
  top: 0;
  display: grid;
  place-items: center;
  width: 40px;
  height: 40px;
  border: 1px solid var(--gold-500);
  background: var(--paper-50);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--gold-700);
}

.page-about .flow__title {
  margin: 8px 0 8px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 800;
  line-height: 1.35;
  color: var(--text-900);
}

.page-about .flow__desc {
  max-width: 34em;
  margin: 0 0 10px;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-900);
}

.page-about .flow__owner {
  display: inline-block;
  margin: 0 0 10px;
  padding: 3px 8px;
  border: 1px solid var(--line-300);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--steel-500);
}

.page-about .flow__more {
  border-left: 1px solid var(--line-300);
  padding-left: 12px;
}

.page-about .flow__more summary {
  padding: 4px 0;
  list-style: none;
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--gold-700);
}

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

.page-about .flow__more summary::before {
  content: "+ ";
  color: var(--gold-500);
}

.page-about .flow__more[open] summary::before {
  content: "− ";
}

.page-about .flow__more p {
  margin: 6px 0 0;
  max-width: 32em;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--muted-600);
}

/* ---------- 覆盖与支持 ---------- */
.page-about .reach-grid {
  display: grid;
  gap: 18px;
  margin-top: 24px;
}

@media (min-width: 720px) {
  .page-about .reach-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.page-about .reach-card {
  padding: 20px;
  border: 1px solid var(--line-300);
  border-top: 2px solid var(--gold-500);
  background: var(--sand-100);
}

.page-about .reach-card__num {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 26px;
  letter-spacing: 0.02em;
  color: var(--gold-700);
}

.page-about .reach-card__label {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-900);
}

.page-about .about-callout {
  display: grid;
  gap: 18px;
  margin-top: 30px;
  padding: clamp(20px, 3vw, 32px);
  background: var(--ink-900);
  border: 1px solid var(--ink-900);
  color: var(--paper-50);
}

@media (min-width: 720px) {
  .page-about .about-callout {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }
}

.page-about .about-callout p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(250, 247, 242, 0.82);
}
<<<END>>>