.page-about {
  --about-cut: 14px;
  --about-rule: 1px solid var(--line);
  color: var(--text);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(24px, 5vw, 48px) 0 clamp(40px, 7vw, 80px);
  background:
    radial-gradient(120% 90% at 84% 6%, rgba(0, 240, 192, .16), transparent 58%),
    radial-gradient(90% 70% at 6% 96%, rgba(255, 182, 39, .07), transparent 62%),
    linear-gradient(180deg, var(--panel) 0%, var(--ink) 100%);
  border-bottom: var(--about-rule);
}

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

.page-about .about-hero-grid {
  display: grid;
  gap: 32px;
  margin-top: clamp(22px, 4vw, 44px);
}

.page-about .about-hero-lead h1 {
  margin: 14px 0 0;
  font-family: var(--font-cn);
  font-size: clamp(30px, 6.4vw, 58px);
  font-weight: 900;
  line-height: 1.08;
  letter-spacing: -0.02em;
  max-width: 18ch;
}

.page-about .about-hero-lead .lede {
  margin: 20px 0 0;
  max-width: 46ch;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.85;
  color: var(--text-2);
}

.page-about .about-plates {
  list-style: none;
  margin: 32px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.page-about .about-plate {
  padding: 14px 12px;
  border: 1px solid var(--edge);
  border-left: 3px solid var(--cyan);
  background: linear-gradient(180deg, rgba(44, 90, 76, .3), rgba(10, 33, 27, .72));
}

.page-about .about-plate .num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(20px, 3vw, 30px);
  font-weight: 600;
  color: var(--cyan-soft);
  letter-spacing: 0.02em;
  line-height: 1.1;
}

.page-about .about-plate .label {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  line-height: 1.5;
  color: var(--text-2);
}

.page-about .about-hero-media {
  border: 1px solid var(--edge);
  background: var(--panel);
}

.page-about .about-hero-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

/* ---------- 章节目录带 ---------- */
.page-about .about-toc-bar {
  position: relative;
  background: var(--stripe);
  border-bottom: var(--about-rule);
}

.page-about .about-toc {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 22px;
  overflow-x: auto;
  padding-block: 12px;
  scrollbar-width: thin;
}

.page-about .about-toc a {
  display: inline-block;
  white-space: nowrap;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--text-2);
  text-decoration: none;
  padding: 4px 2px;
  border-bottom: 1px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.page-about .about-toc a:hover,
.page-about .about-toc a[aria-current="true"] {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

/* ---------- 章节通用 ---------- */
.page-about .about-chapter {
  padding-block: clamp(46px, 7vw, 92px);
  border-bottom: var(--about-rule);
  scroll-margin-top: calc(var(--header-approx) + 12px);
}

.page-about .about-chapter--last {
  border-bottom: none;
}

.page-about .about-chapter-grid {
  display: grid;
  gap: 26px;
}

.page-about .about-chapter-head h2 {
  margin: 12px 0 0;
  font-family: var(--font-cn);
  font-size: clamp(24px, 3.6vw, 38px);
  font-weight: 900;
  line-height: 1.14;
  letter-spacing: -0.02em;
  max-width: 17ch;
}

.page-about .sec-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 40px;
  padding: 4px 9px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--cyan);
  border: 1px solid var(--edge);
  background: rgba(0, 240, 192, .07);
}

.page-about .about-chapter-body .prose {
  max-width: 62ch;
}

.page-about .about-chapter-body .prose + .prose {
  margin-top: 18px;
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: 34px 0 0;
  padding: 0 0 0 24px;
  border-left: 1px solid var(--line);
  display: grid;
  gap: 26px;
}

.page-about .about-timeline li {
  position: relative;
}

.page-about .about-timeline li::before {
  content: "";
  position: absolute;
  left: -29px;
  top: 5px;
  width: 9px;
  height: 9px;
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(0, 240, 192, .12);
}

.page-about .about-tl-time {
  display: block;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--amber);
}

.page-about .about-timeline strong {
  display: block;
  margin-top: 4px;
  font-size: 17px;
  color: var(--text);
}

.page-about .about-timeline p {
  margin: 6px 0 0;
  color: var(--text-2);
  line-height: 1.8;
  font-size: 15px;
}

/* ---------- 三级分类 ---------- */
.page-about .about-levels {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .about-level {
  position: relative;
  padding: 20px 18px 20px 22px;
  border: 1px solid var(--line);
  background: var(--panel);
  border-left: 3px solid var(--edge);
  transition: border-left-color .2s var(--ease), transform .2s var(--ease);
}

.page-about .about-level:hover {
  border-left-color: var(--cyan);
  transform: translateX(3px);
}

.page-about .about-level-no {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--cyan);
}

.page-about .about-level h3 {
  margin: 6px 0 0;
  font-size: 18px;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.page-about .about-level p {
  margin: 8px 0 0;
  color: var(--text-2);
  font-size: 15px;
  line-height: 1.8;
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  display: grid;
  gap: 24px;
}

.page-about .about-team-media {
  border: 1px solid var(--edge);
  background: var(--panel);
}

.page-about .about-team-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .about-roles {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .about-roles li {
  padding: 18px;
  border-top: 1px solid var(--line);
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 6px 14px;
  align-items: baseline;
}

.page-about .about-role-no {
  font-size: 13px;
  color: var(--cyan);
  letter-spacing: 0.1em;
}

.page-about .about-roles strong {
  font-size: 16px;
  font-weight: 800;
}

.page-about .about-roles p {
  grid-column: 2;
  margin: 0;
  color: var(--text-2);
  font-size: 15px;
  line-height: 1.8;
}

/* ---------- 跑道式通栏 ---------- */
.page-about .about-band {
  padding-block: clamp(26px, 4vw, 40px);
  border-left: 4px solid var(--cyan);
  background:
    linear-gradient(90deg, rgba(0, 240, 192, .14), rgba(18, 73, 59, .5) 62%, rgba(4, 16, 13, .2));
  border-top: var(--about-rule);
  border-bottom: var(--about-rule);
}

.page-about .about-band-inner {
  display: grid;
  gap: 10px;
}

.page-about .about-band-text {
  margin: 0;
  max-width: 60ch;
  font-size: clamp(16px, 2vw, 20px);
  font-weight: 700;
  line-height: 1.6;
  letter-spacing: -0.01em;
}

.page-about .about-band-note {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--cyan-soft);
}

/* ---------- 版本演进 ---------- */
.page-about .about-versions-layout {
  display: grid;
  gap: 28px;
}

.page-about .about-versions {
  margin-top: 26px;
  display: grid;
  gap: 10px;
}

.page-about .about-version {
  border: 1px solid var(--line);
  border-left: 3px solid var(--edge);
  background: var(--panel);
}

.page-about .about-version[open] {
  border-left-color: var(--cyan);
  background: linear-gradient(180deg, rgba(0, 240, 192, .06), rgba(10, 33, 27, .9));
}

.page-about .about-version summary {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 16px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-version summary::after {
  content: "＋";
  margin-left: auto;
  font-family: var(--font-mono);
  color: var(--cyan);
}

.page-about .about-version[open] summary::after {
  content: "－";
}

.page-about .v-tag {
  flex: 0 0 auto;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--amber);
  border: 1px solid var(--edge);
  padding: 2px 7px;
}

.page-about .v-name {
  font-size: 15px;
  font-weight: 700;
}

.page-about .about-version-body {
  padding: 0 16px 18px;
}

.page-about .about-version-body p {
  margin: 0;
  color: var(--text-2);
  font-size: 15px;
  line-height: 1.8;
  max-width: 60ch;
}

.page-about .about-versions-media {
  border: 1px solid var(--edge);
  background: var(--panel);
}

.page-about .about-versions-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 14 / 9;
  object-fit: cover;
}

/* ---------- 覆盖范围 ---------- */
.page-about .about-stats {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.page-about .about-stats .data-block {
  padding: 16px 14px;
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(44, 90, 76, .22), rgba(10, 33, 27, .8));
}

.page-about .about-stats .value {
  display: block;
  font-size: clamp(24px, 4vw, 34px);
  font-weight: 600;
  color: var(--cyan-soft);
  line-height: 1.1;
}

.page-about .about-stats .label {
  display: block;
  margin-top: 8px;
  font-size: 12.5px;
  color: var(--text-2);
  line-height: 1.6;
}

.page-about .about-ratio {
  margin-top: 30px;
  padding: 20px 18px;
  border: 1px solid var(--edge);
  background: var(--panel);
}

.page-about .about-ratio-head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
}

.page-about .about-ratio-num {
  font-size: clamp(28px, 5vw, 44px);
  font-weight: 600;
  color: var(--cyan);
  line-height: 1;
}

.page-about .about-ratio-label {
  font-size: 14px;
  color: var(--text-2);
}

.page-about .about-bar {
  margin-top: 16px;
  height: 8px;
  background: var(--stripe);
  overflow: hidden;
}

.page-about .about-bar > span {
  display: block;
  height: 100%;
  width: var(--pct, 60%);
  background: linear-gradient(90deg, var(--cyan), var(--cyan-soft));
}

.page-about .about-ratio .muted {
  margin: 14px 0 0;
  font-size: 13.5px;
  color: var(--text-2);
  line-height: 1.7;
}

/* ---------- 合作生态 ---------- */
.page-about .about-partner-cards {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .about-partner-cards .card {
  padding: 20px 18px;
  border: 1px solid var(--line);
  background: var(--panel);
}

.page-about .about-partner-cards h3 {
  margin: 0;
  font-size: 17px;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.page-about .about-partner-cards p {
  margin: 8px 0 0;
  color: var(--text-2);
  font-size: 15px;
  line-height: 1.8;
}

.page-about .about-partner-cards .card:hover {
  border-color: var(--edge);
}

/* ---------- 延伸入口 ---------- */
.page-about .about-next {
  padding-block: clamp(44px, 6vw, 80px);
  background:
    radial-gradient(90% 120% at 10% 0%, rgba(255, 182, 39, .08), transparent 60%),
    linear-gradient(180deg, var(--ink), var(--panel));
}

.page-about .about-next-grid {
  margin-top: 22px;
  display: grid;
  gap: 14px;
}

.page-about .about-next-card {
  display: block;
  padding: 22px 20px;
  border: 1px solid var(--line);
  border-top: 3px solid var(--edge);
  background: var(--panel);
  text-decoration: none;
  color: var(--text);
  transition: border-top-color .22s var(--ease), transform .22s var(--ease), background .22s var(--ease);
}

.page-about .about-next-card:hover,
.page-about .about-next-card:focus-visible {
  border-top-color: var(--cyan);
  transform: translateY(-3px);
  background: linear-gradient(180deg, rgba(0, 240, 192, .08), rgba(10, 33, 27, .95));
}

.page-about .about-next-card--accent {
  border-top-color: var(--orange);
}

.page-about .about-next-card--accent:hover,
.page-about .about-next-card--accent:focus-visible {
  border-top-color: var(--orange);
}

.page-about .about-next-k {
  display: block;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.page-about .about-next-card--accent .about-next-k {
  color: var(--orange);
}

.page-about .about-next-card strong {
  display: block;
  margin-top: 8px;
  font-size: 19px;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.page-about .about-next-d {
  display: block;
  margin-top: 8px;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--text-2);
}

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

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

  .page-about .about-roles li {
    border-top: 1px solid var(--line);
    border-right: 1px solid var(--line);
    grid-template-columns: auto minmax(0, 1fr);
  }

  .page-about .about-roles li:last-child {
    border-right: none;
  }

  .page-about .about-roles p {
    grid-column: 1 / -1;
    margin-top: 6px;
  }

  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

  .page-about .about-toc {
    justify-content: space-between;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 1000px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
    align-items: end;
    gap: 56px;
  }

  .page-about .about-hero-media img {
    aspect-ratio: 16 / 10;
  }

  .page-about .about-chapter-grid {
    grid-template-columns: 260px minmax(0, 1fr);
    gap: 60px;
  }

  .page-about .about-chapter-head {
    position: sticky;
    top: calc(var(--header-approx) + 16px);
    align-self: start;
  }

  .page-about .about-team {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    align-items: start;
    gap: 36px;
  }

  .page-about .about-versions-layout {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, .65fr);
    align-items: start;
    gap: 36px;
  }

  .page-about .about-band-inner {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 32px;
  }

  .page-about .about-band-note {
    text-align: right;
  }

  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 窄屏细节 ---------- */
@media (max-width: 420px) {
  .page-about .about-plates {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-plate:last-child {
    grid-column: 1 / -1;
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .about-level,
  .page-about .about-next-card {
    transition: none;
  }

  .page-about .about-level:hover,
  .page-about .about-next-card:hover,
  .page-about .about-next-card:focus-visible {
    transform: none;
  }
}

.page-about {
  --pct: 1rem;
}