.page-about {
  --about-index-w: 212px;
  background: var(--ink-900);
  color: var(--text-1);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: 28px 0 36px;
  overflow: hidden;
  background:
    radial-gradient(circle at 92% 0%, rgba(41, 224, 200, .16), transparent 46%),
    radial-gradient(circle at 0% 100%, rgba(255, 122, 46, .13), transparent 42%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(22, 58, 85, .55) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(22, 58, 85, .55) 1px, transparent 1px);
  background-size: 88px 88px;
  opacity: .22;
  pointer-events: none;
  -webkit-mask-image: linear-gradient(to bottom, #000 10%, transparent 92%);
  mask-image: linear-gradient(to bottom, #000 10%, transparent 92%);
}

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

.page-about .breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  margin: 0 0 18px;
  font-size: var(--fs-small);
  color: var(--text-2);
}

.page-about .breadcrumb a {
  color: var(--text-2);
  text-decoration: none;
  transition: color var(--dur) var(--ease);
}

.page-about .breadcrumb a:hover {
  color: var(--cyan);
}

.page-about .breadcrumb span[aria-current] {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--cyan-soft);
}

.page-about .about-hero-frame {
  position: relative;
  display: grid;
  gap: var(--gap);
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  background: linear-gradient(158deg, rgba(11, 30, 51, .95) 0%, rgba(6, 16, 29, .9) 62%);
  box-shadow: 0 40px 90px -60px rgba(0, 0, 0, .95);
}

.page-about .about-hero-frame::after {
  content: "";
  position: absolute;
  top: 12px;
  right: 12px;
  width: 44px;
  height: 44px;
  border-top: 1px solid var(--cyan);
  border-right: 1px solid var(--cyan);
  border-radius: 0 12px 0 0;
  opacity: .55;
  pointer-events: none;
}

.page-about .about-hero-copy {
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-width: 0;
}

.page-about .about-hero-copy .eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: .18em;
  color: var(--amber);
}

.page-about .about-hero-copy h1 {
  margin: 14px 0 18px;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(32px, 6vw, 62px);
  line-height: 1.08;
  letter-spacing: -.02em;
  color: var(--text-1);
}

.page-about .about-hero-copy .lede {
  margin: 0;
  max-width: 52ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--text-2);
}

.page-about .about-hero-facts {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 24px 0 0;
  padding: 0;
}

.page-about .about-hero-facts li {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 7px 15px;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background: var(--cyan-dim);
  font-size: 13px;
  color: var(--text-3);
}

.page-about .about-hero-facts .mono-num {
  font-family: var(--font-mono);
  font-size: 17px;
  font-weight: 700;
  color: var(--cyan-soft);
  letter-spacing: -.01em;
}

.page-about .about-hero-figure {
  position: relative;
  margin: 0;
  min-width: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--ink-800);
}

.page-about .about-hero-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 12 / 8;
  object-fit: cover;
  filter: saturate(.85) contrast(1.04);
}

.page-about .about-hero-figure figcaption {
  padding: 10px 14px;
  border-top: 1px solid var(--line-soft);
  background: rgba(6, 16, 29, .82);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--text-2);
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 36px 0 48px;
  }

  .page-about .about-hero-frame {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    align-items: stretch;
    gap: 32px;
    padding: 28px;
  }

  .page-about .about-hero-copy .lede {
    font-size: var(--fs-body);
  }

  .page-about .about-hero-figure img {
    aspect-ratio: auto;
    height: 100%;
    min-height: 300px;
  }
}

/* ---------- 正文骨架 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
  padding: 44px 0 0;
}

.page-about .about-flow {
  min-width: 0;
}

@media (min-width: 900px) {
  .page-about .about-body {
    grid-template-columns: var(--about-index-w) minmax(0, 1fr);
    gap: 56px;
    align-items: start;
    padding-top: 64px;
  }
}

/* ---------- 左侧章节索引 ---------- */
.page-about .about-index {
  min-width: 0;
  border-top: 1px solid var(--line);
  padding-top: 14px;
}

.page-about .about-index-label {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .2em;
  color: var(--sage);
}

.page-about .about-index-list {
  list-style: none;
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 4px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-index-list li {
  flex: none;
}

.page-about .about-index-list a {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 14px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  color: var(--text-2);
  text-decoration: none;
  font-size: var(--fs-small);
  white-space: nowrap;
  transition: color var(--dur) var(--ease), background var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .about-index-list a:hover,
.page-about .about-index-list a:focus-visible {
  color: var(--text-1);
  background: var(--cyan-dim);
  border-color: var(--line);
  outline: none;
}

.page-about .about-idx-num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .06em;
  color: var(--amber);
}

.page-about .about-index-note {
  display: none;
}

@media (min-width: 900px) {
  .page-about .about-index {
    position: sticky;
    top: 100px;
  }

  .page-about .about-index-list {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-index-note {
    display: block;
    margin: 22px 0 0;
    padding-left: 12px;
    border-left: 2px solid var(--sage);
    font-size: 13px;
    line-height: 1.8;
    color: var(--text-2);
  }
}

/* ---------- 章节通用 ---------- */
.page-about .about-sec {
  padding: 0 0 44px;
  margin-bottom: 44px;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-sec:last-child {
  margin-bottom: 0;
  padding-bottom: 8px;
  border-bottom: 0;
}

.page-about .about-sec-head {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  margin-bottom: 20px;
}

.page-about .about-sec-num {
  flex: none;
  font-family: var(--font-mono);
  font-size: clamp(26px, 3.6vw, 40px);
  font-weight: 700;
  line-height: .95;
  letter-spacing: -.02em;
  color: rgba(41, 224, 200, .3);
  -webkit-text-stroke: 1px var(--cyan);
}

.page-about .about-sec h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(23px, 3.2vw, 38px);
  line-height: 1.24;
  letter-spacing: -.015em;
  color: var(--text-1);
}

.page-about .about-sec .prose {
  max-width: 66ch;
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--text-2);
}

.page-about .about-sec .prose p {
  margin: 0 0 14px;
}

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

@media (min-width: 720px) {
  .page-about .about-sec .prose {
    font-size: var(--fs-body);
  }

  .page-about .about-sec-num {
    font-size: clamp(34px, 3.6vw, 48px);
  }
}

/* ---------- 01 读者三类 ---------- */
.page-about .about-reader-list {
  list-style: none;
  display: grid;
  gap: 14px;
  margin: 26px 0 0;
  padding: 0;
}

.page-about .about-reader {
  position: relative;
  min-width: 0;
  padding: 18px 18px 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(170deg, rgba(11, 30, 51, .9), rgba(6, 16, 29, .72));
}

.page-about .about-reader::after {
  content: "";
  position: absolute;
  left: 18px;
  right: 18px;
  bottom: 0;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--cyan), transparent);
  opacity: .5;
}

.page-about .about-reader h3 {
  margin: 12px 0 8px;
  font-size: 17px;
  font-weight: 500;
  line-height: 1.4;
  color: var(--text-1);
}

.page-about .about-reader p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-2);
}

@media (min-width: 720px) {
  .page-about .about-reader-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
  }
}

/* ---------- 02 组织方法 ---------- */
.page-about .about-method {
  margin: 26px 0 0;
  padding: 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-method-item {
  display: grid;
  gap: 6px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-method dt {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .14em;
  color: var(--cyan);
}

.page-about .about-method dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--text-2);
}

@media (min-width: 720px) {
  .page-about .about-method-item {
    grid-template-columns: 132px minmax(0, 1fr);
    gap: 26px;
    align-items: baseline;
  }
}

.page-about .about-quote {
  position: relative;
  margin: 30px 0 0;
  padding: 26px 22px 22px 46px;
  border: 1px solid rgba(255, 122, 46, .28);
  border-radius: var(--radius-lg);
  background: var(--amber-dim);
}

.page-about .about-quote::before {
  content: "\201C";
  position: absolute;
  top: 4px;
  left: 14px;
  font-family: Georgia, "Times New Roman", serif;
  font-size: 56px;
  line-height: 1;
  color: var(--amber);
  opacity: .7;
}

.page-about .about-quote p {
  margin: 0 0 10px;
  font-size: 16.5px;
  line-height: 1.75;
  color: var(--text-1);
}

.page-about .about-quote cite {
  font-style: normal;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .1em;
  color: var(--amber-soft);
}

/* ---------- 03 版本时间轴 ---------- */
.page-about .about-timeline {
  list-style: none;
  position: relative;
  margin: 28px 0 0;
  padding: 0 0 0 28px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 6px;
  bottom: 6px;
  width: 1px;
  background: linear-gradient(to bottom, var(--cyan), var(--amber), var(--sage));
  opacity: .8;
}

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

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

.page-about .about-tl-mark {
  position: absolute;
  left: -28px;
  top: 5px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--ink-900);
  border: 1px solid var(--cyan);
  transition: background var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .about-tl-item:hover .about-tl-mark {
  background: var(--cyan);
  box-shadow: 0 0 0 4px var(--cyan-dim);
}

.page-about .about-tl-version {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .14em;
  color: var(--amber-soft);
}

.page-about .about-tl-body h3 {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 500;
  line-height: 1.45;
  color: var(--text-1);
}

.page-about .about-tl-body p {
  margin: 0;
  max-width: 60ch;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--text-2);
}

/* ---------- 通用图注模块 ---------- */
.page-about .about-figure {
  margin: 28px 0 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: rgba(11, 30, 51, .6);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-figure figcaption {
  padding: 10px 16px;
  border-top: 1px solid var(--line-soft);
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.7;
  letter-spacing: .06em;
  color: var(--text-2);
}

/* ---------- 04 团队与流程 ---------- */
.page-about .about-team-stats {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin: 24px 0 0;
  padding: 0;
}

.page-about .about-team-stats li {
  min-width: 0;
  padding: 14px 10px;
  border: 1px solid rgba(111, 143, 131, .38);
  border-radius: var(--radius-md);
  background: var(--sage-dim);
  text-align: center;
}

.page-about .about-stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(24px, 4vw, 34px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--cyan-soft);
}

.page-about .about-team-stats li > span:last-child {
  display: block;
  margin-top: 4px;
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--text-3);
}

.page-about .about-flow-list {
  list-style: none;
  display: grid;
  gap: 16px;
  margin: 26px 0 0;
  padding: 0;
}

.page-about .about-flow-step {
  position: relative;
  min-width: 0;
  padding: 20px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: rgba(11, 30, 51, .66);
}

.page-about .about-flow-step::before {
  content: "";
  position: absolute;
  top: 0;
  left: 18px;
  right: 18px;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--cyan), var(--amber));
}

.page-about .about-flow-num {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--amber);
}

.page-about .about-flow-step h3 {
  margin: 8px 0;
  font-size: 17px;
  font-weight: 500;
  color: var(--text-1);
}

.page-about .about-flow-step p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-2);
}

@media (min-width: 720px) {
  .page-about .about-flow-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }
}

/* ---------- 05 服务原则 ---------- */
.page-about .about-principles {
  display: grid;
  gap: 14px;
  margin-top: 24px;
}

.page-about .about-principle {
  min-width: 0;
  padding: 20px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(160deg, rgba(11, 30, 51, .85), rgba(6, 16, 29, .6));
}

.page-about .about-principle h3 {
  margin: 0 0 10px;
  font-size: 16px;
  font-weight: 600;
  letter-spacing: .02em;
  color: var(--cyan-soft);
}

.page-about .about-principle p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--text-2);
}

@media (min-width: 720px) {
  .page-about .about-principles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px;
  }
}

.page-about .about-inline-link {
  margin: 24px 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--cyan);
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--text-2);
}

.page-about .about-inline-link a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(41, 224, 200, .35);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .about-inline-link a:hover {
  color: var(--cyan-soft);
  border-color: var(--cyan-soft);
}

/* ---------- 收尾行动区 ---------- */
.page-about .about-cta {
  padding: 12px 0 64px;
}

.page-about .about-cta-inner {
  position: relative;
  overflow: hidden;
  padding: 30px 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  background:
    radial-gradient(circle at 88% 12%, rgba(255, 122, 46, .2), transparent 52%),
    radial-gradient(circle at 6% 92%, rgba(41, 224, 200, .18), transparent 50%),
    linear-gradient(160deg, rgba(11, 30, 51, .95), rgba(6, 16, 29, .92));
}

.page-about .about-cta-inner .eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: .2em;
  color: var(--amber);
}

.page-about .about-cta-inner h2 {
  margin: 12px 0 14px;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(24px, 3.4vw, 40px);
  line-height: 1.22;
  letter-spacing: -.015em;
  color: var(--text-1);
}

.page-about .about-cta-inner p {
  margin: 0;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--text-2);
}

.page-about .about-cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

@media (min-width: 720px) {
  .page-about .about-cta {
    padding: 20px 0 80px;
  }

  .page-about .about-cta-inner {
    padding: 44px 40px;
  }
}