.page-about {
  --about-grid: rgba(30, 74, 64, 0.34);
  --about-thread: rgba(30, 74, 64, 0.78);
  --about-panel: rgba(12, 42, 35, 0.72);
  position: relative;
  background-image:
    linear-gradient(var(--about-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--about-grid) 1px, transparent 1px);
  background-size: 96px 96px;
  background-position: -1px -1px;
}

.page-about .breadcrumb {
  padding: 22px 0 0;
  font-size: 13px;
  color: var(--muted);
}

.page-about .breadcrumb a {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--t-fast) var(--ease), border-color var(--t-fast) var(--ease);
}

.page-about .breadcrumb a:hover,
.page-about .breadcrumb a:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.page-about .breadcrumb__sep {
  margin: 0 8px;
  color: var(--line);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(36px, 7vw, 88px) 0 clamp(48px, 8vw, 104px);
}

.page-about .about-hero__slice {
  position: absolute;
  top: -30%;
  right: -14%;
  width: min(52vw, 560px);
  height: 160%;
  border-radius: var(--r-lg);
  background: linear-gradient(165deg, rgba(46, 242, 204, 0.1), rgba(240, 180, 41, 0.04) 62%, transparent);
  transform: rotate(13deg);
  pointer-events: none;
}

.page-about .about-hero__glow {
  position: absolute;
  left: 30%;
  bottom: -10%;
  width: 60%;
  height: 340px;
  background: radial-gradient(closest-side, rgba(46, 242, 204, 0.14), transparent 78%);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 40px);
}

.page-about .about-hero__head {
  max-width: 20ch;
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(38px, 8.4vw, 96px);
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-about .about-hero__lead {
  margin: 0;
  max-width: 62ch;
  color: var(--mist);
}

.page-about .hero-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  background: var(--about-thread);
  border: 1px solid var(--about-thread);
  border-radius: var(--r-md);
  overflow: hidden;
}

.page-about .hero-facts__item {
  padding: clamp(16px, 2.6vw, 26px);
  background: var(--ink-900);
}

.page-about .hero-facts dt {
  margin: 0 0 8px;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.page-about .hero-facts__num {
  margin: 0;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  font-size: clamp(30px, 5vw, 40px);
  line-height: 1;
  color: var(--cyan);
}

.page-about .hero-facts__unit {
  margin-left: 2px;
  font-size: 0.5em;
  color: var(--amber);
}

/* ---------- 章节骨架 ---------- */

.page-about .chapter {
  position: relative;
  padding: 0 0 clamp(56px, 9vw, 120px);
  scroll-margin-top: calc(var(--topbar-h) + 16px);
}

.page-about .chapter__inner {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(16px, 4vw, 32px);
  padding-top: clamp(34px, 5vw, 64px);
}

.page-about .chapter__inner::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--cyan) 0, var(--about-thread) 12%, rgba(30, 74, 64, 0.12) 82%, transparent 100%);
}

.page-about .chapter__index {
  display: flex;
  align-items: baseline;
  gap: 14px;
}

.page-about .chapter__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  font-size: clamp(54px, 13vw, 92px);
  line-height: 0.86;
  letter-spacing: -0.04em;
  color: rgba(240, 180, 41, 0.16);
  -webkit-text-stroke: 1.6px var(--amber);
}

.page-about .chapter__kicker {
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--mist);
  white-space: nowrap;
}

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

.page-about .chapter__body h2 {
  margin: 0 0 20px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(28px, 4.4vw, 40px);
  line-height: 1.18;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-about .chapter__body p {
  margin: 0 0 18px;
  max-width: 68ch;
  color: var(--white);
}

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

.page-about .chapter__body a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(46, 242, 204, 0.4);
  transition: border-color var(--t-fast) var(--ease), color var(--t-fast) var(--ease);
}

.page-about .chapter__body a:hover,
.page-about .chapter__body a:focus-visible {
  color: var(--mist);
  border-bottom-color: var(--mist);
}

/* ---------- 图 ---------- */

.page-about .about-figure {
  margin: 28px 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: var(--r-md);
  border: 1px solid var(--line);
  background: var(--ink-800);
}

.page-about .about-figure--map img {
  aspect-ratio: 11 / 7.6;
}

.page-about .about-figure--square {
  max-width: 460px;
}

.page-about .about-figure--square img {
  aspect-ratio: 1 / 1;
}

.page-about .about-figure__cap {
  margin: 12px 0 0;
  font-size: 12px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 团队构成 ---------- */

.page-about .crew {
  margin: 30px 0 0;
}

.page-about .crew__bar {
  display: flex;
  flex-direction: column;
  gap: 1px;
  border-radius: var(--r-sm);
  overflow: hidden;
  border: 1px solid var(--line);
}

.page-about .crew__seg {
  display: block;
  padding: 16px 18px;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 14px;
  letter-spacing: 0.02em;
}

.page-about .crew__seg--editor {
  background: linear-gradient(90deg, rgba(46, 242, 204, 0.92), rgba(46, 242, 204, 0.62));
  color: var(--ink-900);
  font-weight: 700;
}

.page-about .crew__seg--eng {
  background: rgba(46, 242, 204, 0.1);
  color: var(--cyan);
}

.page-about .crew__cards {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: 18px;
  background: var(--about-thread);
  border: 1px solid var(--about-thread);
  border-radius: var(--r-md);
  overflow: hidden;
}

.page-about .crew-card {
  padding: clamp(18px, 3vw, 26px);
  background: var(--ink-900);
  transition: background var(--t) var(--ease);
}

.page-about .crew-card:hover,
.page-about .crew-card:focus-within,
.page-about .crew-card:focus-visible {
  background: var(--ink-800);
  outline: none;
}

.page-about .crew-card:focus-visible {
  box-shadow: inset 0 0 0 1px var(--cyan);
}

.page-about .crew-card__role {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 22px;
  line-height: 1.3;
  color: var(--white);
}

.page-about .crew-card:hover .crew-card__role,
.page-about .crew-card:focus-within .crew-card__role {
  color: var(--amber);
}

.page-about .crew-card__detail {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
  transition: color var(--t) var(--ease);
}

.page-about .crew-card:hover .crew-card__detail,
.page-about .crew-card:focus-within .crew-card__detail {
  color: var(--white);
}

/* ---------- 版本演进时间线 ---------- */

.page-about .vtl {
  margin: 30px 0 0;
  overflow-x: auto;
  overscroll-behavior-x: contain;
  padding-bottom: 10px;
  scrollbar-color: var(--line) transparent;
}

.page-about .vtl:focus-visible {
  outline: 1px solid var(--cyan);
  outline-offset: 6px;
  border-radius: var(--r-sm);
}

.page-about .vtl__track {
  min-width: 900px;
}

.page-about .vtl__line {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .vtl__spark {
  stroke: var(--cyan);
  opacity: 0.7;
}

.page-about .vtl__dot {
  fill: var(--amber);
}

.page-about .vtl__nodes {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 18px;
  margin: 6px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .vtl__node {
  padding: 18px 16px 20px;
  background: var(--about-panel);
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
}

.page-about .vtl__node h3 {
  margin: 12px 0 8px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 17px;
  line-height: 1.35;
  color: var(--white);
}

.page-about .vtl__node p {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .pullquote {
  margin: 34px 0 26px;
  max-width: 34ch;
  font-family: var(--font-head);
  font-style: italic;
  font-weight: 800;
  font-size: clamp(22px, 3.4vw, 30px);
  line-height: 1.4;
  letter-spacing: -0.01em;
  color: var(--mist);
  border-left: 2px solid var(--amber);
  padding-left: clamp(16px, 3vw, 28px);
}

/* ---------- 服务对象 ---------- */

.page-about .clients {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 30px 0 0;
  background: var(--about-thread);
  border: 1px solid var(--about-thread);
  border-radius: var(--r-md);
  overflow: hidden;
}

.page-about .client {
  padding: clamp(18px, 3vw, 28px);
  background: var(--ink-900);
}

.page-about .client__name {
  margin: 0 0 12px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 17px;
  line-height: 1.4;
  color: var(--cyan);
}

.page-about .client__need {
  margin: 0 0 10px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--white);
}

.page-about .client__how {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .clients__foot {
  margin: 18px 0 0;
  font-size: 14px;
  color: var(--muted);
}

/* ---------- 注释与分隔 ---------- */

.page-about .rule {
  height: 1px;
  margin: 26px 0 18px;
  background: linear-gradient(90deg, var(--about-thread) 0, rgba(30, 74, 64, 0.1) 70%, transparent 100%);
}

.page-about .about-note {
  margin: 0;
  font-size: 12px;
  line-height: 1.75;
  color: var(--muted);
  max-width: 60ch;
}

/* ---------- 结尾行动 ---------- */

.page-about .about-cta {
  position: relative;
  margin-top: clamp(24px, 5vw, 56px);
  padding: clamp(40px, 7vw, 88px) 0;
  border-top: 1px solid var(--about-thread);
  background: linear-gradient(180deg, rgba(240, 180, 41, 0.05), transparent 70%);
}

.page-about .about-cta__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(18px, 3vw, 28px);
}

.page-about .about-cta__title {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(28px, 5vw, 64px);
  line-height: 1.08;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-about .about-cta__text {
  margin: 0;
  max-width: 62ch;
  color: var(--mist);
}

.page-about .about-cta__text a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(46, 242, 204, 0.4);
}

.page-about .about-cta__text a:hover,
.page-about .about-cta__text a:focus-visible {
  border-bottom-color: var(--mist);
}

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

/* ---------- 响应式 ---------- */

@media (min-width: 640px) {
  .page-about .crew__bar {
    flex-direction: row;
  }

  .page-about .crew__seg--editor {
    flex: 46 1 0;
  }

  .page-about .crew__seg--eng {
    flex: 21 1 0;
  }

  .page-about .crew__cards {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

@media (min-width: 860px) {
  .page-about .chapter__inner {
    grid-template-columns: minmax(140px, 210px) minmax(0, 1fr);
    gap: clamp(32px, 5vw, 72px);
  }

  .page-about .chapter__index {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
    position: sticky;
    top: calc(var(--topbar-h) + 28px);
    align-self: start;
  }
}

@media (min-width: 1024px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.15fr) minmax(320px, 0.85fr);
    align-items: start;
    gap: clamp(32px, 5vw, 72px);
  }

  .page-about .about-hero__head {
    grid-column: 1 / -1;
    max-width: 18ch;
  }

  .page-about .about-hero__lead {
    grid-column: 1;
  }

  .page-about .hero-facts {
    grid-column: 2;
    grid-row: 2;
  }

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

  .page-about .about-cta__title {
    grid-column: 1;
  }

  .page-about .about-cta__text {
    grid-column: 1;
  }

  .page-about .about-cta__actions {
    grid-column: 2;
    grid-row: 1 / span 2;
    align-self: end;
    flex-wrap: nowrap;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .crew-card,
  .page-about .crew-card__role,
  .page-about .crew-card__detail,
  .page-about .breadcrumb a {
    transition: none;
  }
}
</main>