.page-about {
  background: var(--va-void);
  color: var(--va-ink);
}

/* ============ 首屏 ============ */
.page-about .about-hero {
  position: relative;
  padding: clamp(104px, 13vw, 168px) 0 clamp(24px, 4vw, 40px);
  background-image:
    linear-gradient(to right, rgba(34, 48, 79, 0.42) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(34, 48, 79, 0.42) 1px, transparent 1px);
  background-size: 64px 64px;
  background-position: 0 0;
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 32px;
  margin-top: 26px;
}

.page-about .about-hero__title {
  margin: 16px 0 0;
  font-family: var(--va-font-display);
  font-weight: 900;
  font-size: clamp(30px, 5vw, 72px);
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--va-ink);
}

.page-about .about-hero__lede {
  margin: 20px 0 0;
  max-width: 36em;
  font-size: clamp(15px, 1.4vw, 17px);
  line-height: 1.9;
  color: var(--va-mist);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  border: 1px solid var(--va-line);
  background: var(--va-line);
}

.page-about .about-hero__stat {
  background: var(--va-cabin);
  padding: 16px 18px;
}

.page-about .about-hero__stat-label {
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--va-mist);
}

.page-about .about-hero__stat-num {
  margin: 6px 0 0;
  font-family: var(--va-font-mono);
  font-size: clamp(24px, 3.4vw, 36px);
  line-height: 1;
  font-variant-numeric: tabular-nums;
  color: var(--va-ink);
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 0;
  }
  .page-about .about-hero__lead {
    grid-column: 1 / span 7;
    padding-right: 32px;
  }
  .page-about .about-hero__stats {
    grid-column: 9 / span 4;
    align-self: end;
  }
}

/* ============ 首屏横幅图 ============ */
.page-about .about-banner {
  margin: clamp(32px, 5vw, 56px) auto 0;
}

.page-about .about-banner img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--va-line);
  border-radius: var(--va-radius);
  object-fit: cover;
  aspect-ratio: 16 / 9;
}

.page-about .about-banner__cap {
  margin-top: 10px;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--va-mist);
}

/* ============ 章节导航 ============ */
.page-about .about-toc {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 20px;
  margin: clamp(36px, 5vw, 60px) 0 clamp(36px, 5vw, 64px);
  padding: 16px 0;
  border-top: 1px solid var(--va-line);
  border-bottom: 1px solid var(--va-line);
}

.page-about .about-toc__label {
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--va-mist);
}

.page-about .about-toc__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-toc__link {
  font-size: 13.5px;
  color: var(--va-ink);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.16s var(--va-ease), border-color 0.16s var(--va-ease);
}

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

/* ============ 章节框架 ============ */
.page-about .about-chapter {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
  padding: clamp(36px, 5.5vw, 68px) 0;
  border-top: 1px solid var(--va-line);
}

.page-about .about-chapter--last {
  padding-bottom: clamp(20px, 3vw, 32px);
}

@media (min-width: 960px) {
  .page-about .about-chapter {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 0;
    min-height: 96px;
  }
  .page-about .about-chapter__main {
    grid-column: 1 / span 8;
    padding-right: 40px;
  }
  .page-about .about-chapter__aside {
    grid-column: 10 / span 3;
  }
}

.page-about .about-chapter__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 22px;
}

.page-about .about-chapter__head::before {
  content: "";
  flex: 0 0 auto;
  align-self: center;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--va-cyan);
}

.page-about .about-chapter__num {
  flex: 0 0 auto;
  font-family: var(--va-font-mono);
  font-weight: 400;
  font-size: clamp(36px, 5.4vw, 88px);
  line-height: 0.78;
  letter-spacing: -0.03em;
  color: var(--va-line);
}

.page-about .about-chapter__title {
  margin: 0;
  font-family: var(--va-font-display);
  font-size: clamp(22px, 2.6vw, 34px);
  font-weight: 800;
  line-height: 1.24;
  letter-spacing: -0.01em;
  color: var(--va-ink);
}

.page-about .about-chapter__main p {
  max-width: 38em;
  margin: 0 0 16px;
  font-family: var(--va-font-serif);
  font-size: 17px;
  line-height: 2;
  color: var(--va-ink);
}

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

/* ============ 浅底阅读块 ============ */
.page-about .about-readblock {
  background: var(--va-paper);
  color: #141A28;
  padding: clamp(26px, 3.4vw, 44px) clamp(20px, 3.2vw, 44px);
  border-radius: var(--va-radius);
}

.page-about .about-readblock .about-chapter__title {
  color: #141A28;
}

.page-about .about-readblock .about-chapter__num {
  color: rgba(20, 26, 40, 0.22);
}

.page-about .about-readblock .about-chapter__head::before {
  background: var(--va-lava-deep);
}

.page-about .about-readblock p {
  color: #2A3242;
}

/* ============ 侧栏批注 ============ */
.page-about .about-chapter__aside {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.page-about .about-note {
  padding-left: 14px;
  border-left: 1px solid var(--va-line);
}

.page-about .about-note__num {
  display: block;
  font-family: var(--va-font-mono);
  font-size: clamp(22px, 2.2vw, 28px);
  line-height: 1.1;
  font-variant-numeric: tabular-nums;
  color: var(--va-ink);
}

.page-about .about-note__text {
  display: block;
  margin-top: 6px;
  font-size: 12.5px;
  line-height: 1.7;
  letter-spacing: 0.02em;
  color: var(--va-mist);
}

/* ============ 图片 ============ */
.page-about .about-figure {
  margin: clamp(24px, 3.4vw, 40px) 0 0;
}

.page-about .about-figure .va-media__img {
  width: 100%;
  height: auto;
  border: 1px solid var(--va-line);
  border-radius: var(--va-radius);
  object-fit: cover;
}

.page-about .about-figure .va-media__cap {
  margin-top: 10px;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--va-mist);
}

/* ============ 团队比例条 ============ */
.page-about .about-roles {
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 12px;
}

.page-about .about-role {
  padding: 14px 16px;
  border: 1px solid var(--va-line);
  border-radius: var(--va-radius);
  background: linear-gradient(180deg, rgba(14, 26, 56, 0.9), rgba(7, 14, 34, 0.9));
  transition: border-color 0.2s var(--va-ease);
}

.page-about .about-role:hover,
.page-about .about-role:focus-within {
  border-color: var(--va-lava-deep);
}

.page-about .about-role__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 6px 14px;
}

.page-about .about-role__name {
  font-size: 15px;
  font-weight: 600;
  color: var(--va-ink);
}

.page-about .about-role__count {
  font-family: var(--va-font-mono);
  font-size: 13px;
  font-variant-numeric: tabular-nums;
  color: var(--va-mist);
}

.page-about .about-role__bar {
  margin-top: 10px;
  height: 6px;
  background: var(--va-line);
  border-radius: 3px;
  overflow: hidden;
}

.page-about .about-role__fill {
  display: block;
  height: 100%;
  background: var(--va-cyan);
  border-radius: 3px;
}

.page-about .about-role--annotate .about-role__fill { width: 64.7%; }
.page-about .about-role--squad .about-role__fill { width: 14.7%; }
.page-about .about-role--table .about-role__fill { width: 8.8%; }
.page-about .about-role--review .about-role__fill { width: 11.8%; }

.page-about .about-role__tip {
  max-height: 0;
  margin: 0;
  overflow: hidden;
  opacity: 0;
  font-size: 13px;
  line-height: 1.75;
  color: var(--va-mist);
  transition: max-height 0.3s var(--va-ease), opacity 0.3s var(--va-ease), margin-top 0.3s var(--va-ease);
}

.page-about .about-role:hover .about-role__tip,
.page-about .about-role:focus-within .about-role__tip {
  max-height: 160px;
  margin-top: 10px;
  opacity: 1;
}

@media (max-width: 959px) {
  .page-about .about-role__tip {
    max-height: none;
    margin-top: 10px;
    opacity: 1;
  }
}

/* ============ 版本筛选与时间线 ============ */
.page-about .about-tl-filter {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-top: clamp(24px, 3.4vw, 38px);
}

.page-about .about-tl-filter__label {
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--va-mist);
  margin-right: 4px;
}

.page-about .about-tl-filter .va-filter__meta {
  font-size: 12.5px;
  color: var(--va-mist);
  margin-left: auto;
}

.page-about .about-timeline {
  position: relative;
  margin-top: clamp(24px, 3.4vw, 36px);
  padding-left: 24px;
  color: var(--va-line);
}

.page-about .about-timeline__axis {
  position: absolute;
  left: 4px;
  top: 8px;
  width: 2px;
  height: calc(100% - 26px);
  display: block;
}

.page-about .about-timeline__list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-tl__node {
  position: relative;
  padding-bottom: 30px;
}

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

.page-about .about-tl__node::before {
  content: "";
  position: absolute;
  left: -24px;
  top: 6px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--va-lava);
  box-shadow: 0 0 0 4px rgba(255, 106, 43, 0.13);
}

.page-about .about-tl__ver {
  display: inline-block;
  font-family: var(--va-font-mono);
  font-size: 11.5px;
}

.page-about .about-tl__title {
  margin: 10px 0 8px;
  font-family: var(--va-font-display);
  font-size: clamp(17px, 1.7vw, 20px);
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--va-ink);
}

.page-about .about-tl__body {
  margin: 0;
  max-width: 38em;
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--va-mist);
}

/* ============ 合作与认可 ============ */
.page-about .about-partners {
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 1px;
  background: var(--va-line);
  border: 1px solid var(--va-line);
  border-radius: var(--va-radius);
  overflow: hidden;
}

.page-about .about-partners__item {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 16px 18px;
  background: var(--va-cabin);
}

.page-about .about-partners__num {
  flex: 0 0 auto;
  min-width: 62px;
  font-family: var(--va-font-mono);
  font-size: 26px;
  line-height: 1;
  font-variant-numeric: tabular-nums;
  color: var(--va-lava);
}

.page-about .about-partners__text {
  font-size: 14px;
  line-height: 1.8;
  color: var(--va-ink);
}

/* ============ 使用场景 ============ */
.page-about .about-serve {
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

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

.page-about .about-serve__card {
  padding: 22px 20px 24px;
  border: 1px solid var(--va-line);
  border-radius: var(--va-radius);
  background: var(--va-cabin);
  transition: border-color 0.2s var(--va-ease), transform 0.2s var(--va-ease);
}

.page-about .about-serve__card:hover {
  border-color: var(--va-cyan);
  transform: translateY(-2px);
}

.page-about .about-serve__tag {
  font-size: 11.5px;
  letter-spacing: 0.08em;
}

.page-about .about-serve__title {
  margin: 14px 0 10px;
  font-family: var(--va-font-display);
  font-size: 17px;
  font-weight: 800;
  line-height: 1.4;
  color: var(--va-ink);
}

.page-about .about-serve__text {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.9;
  color: var(--va-mist);
}

.page-about .about-serve__note {
  margin: clamp(20px, 2.6vw, 28px) 0 0;
  font-size: 14px;
  line-height: 1.9;
  color: var(--va-mist);
}

.page-about .about-serve__link {
  color: var(--va-cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(56, 242, 210, 0.45);
  transition: border-color 0.16s var(--va-ease);
}

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

/* ============ 收尾行动区 ============ */
.page-about .about-cta {
  margin-top: clamp(48px, 7vw, 88px);
  padding: clamp(48px, 7vw, 84px) 0 clamp(56px, 8vw, 92px);
  border-top: 1px solid var(--va-line);
  background:
    radial-gradient(120% 140% at 12% 0%, rgba(56, 242, 210, 0.08), transparent 58%),
    linear-gradient(180deg, var(--va-cabin), var(--va-void));
}

.page-about .about-cta__inner {
  max-width: 640px;
}

.page-about .about-cta__title {
  margin: 14px 0 0;
  font-family: var(--va-font-display);
  font-size: clamp(24px, 3.4vw, 42px);
  font-weight: 900;
  line-height: 1.14;
  letter-spacing: -0.02em;
  color: var(--va-ink);
}

.page-about .about-cta__text {
  margin: 16px 0 0;
  max-width: 34em;
  font-size: 15px;
  line-height: 1.9;
  color: var(--va-mist);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-role,
  .page-about .about-role__tip,
  .page-about .about-serve__card,
  .page-about .about-toc__link,
  .page-about .about-serve__link {
    transition: none;
  }
  .page-about .about-serve__card:hover {
    transform: none;
  }
}