.page-about {
  --about-rail-w: 216px;
  --about-dot: 16px;
  --about-soft-text: rgba(244, 239, 230, 0.84);
  display: block;
  background: var(--bg);
  color: var(--text);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(26px, 5vw, 64px) 0 clamp(34px, 6vw, 76px);
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -30%;
  right: -18%;
  width: min(760px, 90vw);
  height: min(760px, 90vw);
  background: radial-gradient(circle, rgba(255, 106, 31, 0.16) 0%, rgba(51, 214, 198, 0.08) 42%, transparent 70%);
  pointer-events: none;
}

.page-about .about-hero__grid {
  position: relative;
  display: grid;
  gap: clamp(26px, 4vw, 48px);
}

.page-about .about-hero__title {
  font-family: var(--ff-display);
  font-size: clamp(32px, 6.6vw, 80px);
  line-height: 1.04;
  letter-spacing: -0.02em;
  margin: 14px 0 0;
  max-width: 16ch;
}

.page-about .about-hero__lede {
  margin: 18px 0 0;
  max-width: 46ch;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.8;
  color: var(--about-soft-text);
}

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px 18px;
  margin: 30px 0 0;
  padding: 0;
}

.page-about .about-stat {
  border-left: 2px solid var(--orange);
  padding-left: 12px;
}

.page-about .about-stat--cyan {
  border-left-color: var(--cyan);
}

.page-about .about-stat dt {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--muted);
  line-height: 1.4;
}

.page-about .about-stat dd {
  margin: 6px 0 0;
  font-family: var(--ff-data);
  font-size: clamp(22px, 2.6vw, 30px);
  letter-spacing: 0.04em;
  color: var(--paper);
  line-height: 1.1;
}

/* ---------- 图片 ---------- */
.page-about .about-fig {
  margin: 0;
  position: relative;
}

.page-about .about-fig img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: var(--radius);
  border: 1px solid var(--line-soft);
  background: var(--ink-600);
}

.page-about .about-hero__fig img {
  aspect-ratio: 14 / 9;
}

.page-about .about-fig figcaption {
  margin-top: 10px;
  font-size: 12.5px;
  line-height: 1.6;
  letter-spacing: 0.02em;
  color: var(--muted);
}

/* ---------- 主体骨架 ---------- */
.page-about .about-body {
  display: grid;
  gap: clamp(26px, 4vw, 52px);
  padding: clamp(34px, 6vw, 68px) 0 clamp(48px, 8vw, 96px);
}

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

.page-about .about-sec + .about-sec {
  margin-top: clamp(48px, 8vw, 96px);
}

.page-about .about-sec__head {
  margin-bottom: clamp(20px, 3vw, 32px);
}

.page-about .about-sec h2 {
  font-family: var(--ff-display);
  font-size: clamp(23px, 3.4vw, 40px);
  line-height: 1.16;
  letter-spacing: -0.01em;
  margin: 8px 0 0;
  max-width: 20ch;
}

.page-about .about-sec__intro {
  margin: 14px 0 0;
  max-width: 52ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 侧栏目录 ---------- */
.page-about .about-rail {
  display: none;
}

.page-about .about-rail__label {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--muted);
}

.page-about .about-rail__nav {
  display: grid;
  gap: 2px;
}

.page-about .about-rail__nav a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 8px 10px 8px 12px;
  border-left: 1px solid var(--line);
  color: var(--muted);
  text-decoration: none;
  font-size: 13px;
  line-height: 1.5;
  transition: color var(--t) var(--ease), border-color var(--t) var(--ease), background-color var(--t) var(--ease);
}

.page-about .about-rail__nav a .mono {
  font-size: 11px;
  color: rgba(143, 160, 188, 0.8);
}

.page-about .about-rail__nav a:hover {
  color: var(--paper);
  border-left-color: var(--cyan-deep);
}

.page-about .about-rail__nav a.is-active {
  border-left-color: var(--orange);
  background: rgba(255, 106, 31, 0.08);
  color: var(--paper);
}

.page-about .about-rail__nav a.is-active .mono {
  color: var(--orange);
}

.page-about .about-rail__nav a:focus-visible {
  outline: 2px solid var(--orange);
  outline-offset: 2px;
}

/* ---------- 正文 ---------- */
.page-about .prose {
  max-width: 62ch;
}

.page-about .prose p {
  margin: 0 0 16px;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--about-soft-text);
}

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

.page-about .prose a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(51, 214, 198, 0.45);
}

.page-about .prose a:hover {
  color: var(--paper);
  border-bottom-color: var(--orange);
}

/* ---------- 起点 ---------- */
.page-about .origin-grid {
  display: grid;
  gap: 22px;
}

.page-about .origin-note {
  border-left: 2px solid var(--orange);
  padding-left: 14px;
  align-self: start;
}

.page-about .origin-note .mono {
  display: block;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--orange-soft);
}

.page-about .origin-note p {
  margin: 8px 0 0;
  font-size: 13px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 时间轴 ---------- */
.page-about .timeline {
  position: relative;
  margin-top: 8px;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--orange) 0%, var(--cyan-deep) 58%, rgba(30, 51, 88, 0.9) 100%);
}

.page-about .tl-node {
  position: relative;
  padding-left: 34px;
  margin: 0 0 16px;
}

.page-about .tl-node:last-child {
  margin-bottom: 0;
}

.page-about .tl-node::before {
  content: "";
  position: absolute;
  left: 0;
  top: 20px;
  width: var(--about-dot);
  height: var(--about-dot);
  border-radius: 50%;
  background: var(--orange);
  box-shadow: 0 0 0 4px var(--bg);
}

.page-about .tl-node--now::before {
  background: var(--cyan);
  box-shadow: 0 0 0 4px var(--bg), 0 0 0 7px rgba(51, 214, 198, 0.18);
}

.page-about .tl-card {
  background: var(--surface);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  transition: border-color var(--t) var(--ease), background-color var(--t) var(--ease);
}

.page-about .tl-card > summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 14px;
  padding: 15px 16px;
  cursor: pointer;
  list-style: none;
}

.page-about .tl-card > summary::-webkit-details-marker {
  display: none;
}

.page-about .tl-card > summary:focus-visible {
  outline: 2px solid var(--orange);
  outline-offset: -2px;
}

.page-about .tl-card > summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--ff-data);
  font-size: 16px;
  line-height: 1;
  color: var(--orange);
}

.page-about .tl-card[open] > summary::after {
  content: "−";
}

.page-about .tl-card:hover {
  border-color: rgba(51, 214, 198, 0.35);
}

.page-about .tl-card[open] {
  border-color: rgba(255, 106, 31, 0.5);
  background: linear-gradient(180deg, rgba(30, 51, 88, 0.92), var(--surface));
}

.page-about .tl-card--now {
  border-color: rgba(51, 214, 198, 0.4);
}

.page-about .tl-card__code {
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--cyan);
  border: 1px solid rgba(51, 214, 198, 0.35);
  border-radius: 2px;
  padding: 2px 6px;
  line-height: 1.4;
}

.page-about .tl-card--now .tl-card__code {
  color: var(--orange);
  border-color: rgba(255, 106, 31, 0.45);
}

.page-about .tl-card__title {
  font-size: clamp(14.5px, 1.6vw, 17px);
  font-weight: 700;
  line-height: 1.55;
  color: var(--paper);
}

.page-about .tl-card__body {
  padding: 0 16px 18px;
}

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

.page-about .tl-list {
  margin: 12px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 6px;
}

.page-about .tl-list li {
  position: relative;
  padding-left: 16px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .tl-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 6px;
  height: 6px;
  border-radius: 1px;
  background: var(--cyan-deep);
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  gap: 26px;
}

.page-about .team-roster {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .team-roster li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 2px 14px;
  padding: 12px 14px;
  border: 1px solid var(--line-soft);
  border-left: 2px solid var(--orange);
  border-radius: var(--radius);
  background: rgba(18, 32, 58, 0.55);
}

.page-about .team-roster__num {
  grid-row: span 2;
  align-self: center;
  font-family: var(--ff-data);
  font-size: 24px;
  letter-spacing: 0.04em;
  color: var(--orange);
  line-height: 1;
}

.page-about .team-roster__name {
  font-size: 14.5px;
  font-weight: 700;
  color: var(--paper);
  line-height: 1.5;
}

.page-about .team-roster__desc {
  grid-column: 2;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 资质 ---------- */
.page-about .trust-grid {
  display: grid;
  gap: 26px;
}

.page-about .about-list {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .about-list li {
  position: relative;
  padding: 14px 0 14px 18px;
  border-bottom: 1px solid var(--line-soft);
  border-left: 2px solid var(--cyan-deep);
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--about-soft-text);
}

.page-about .about-list li:first-child {
  border-top: 1px solid var(--line-soft);
}

.page-about .about-list .mono {
  display: inline-block;
  margin-right: 10px;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

/* ---------- 品牌矩阵 ---------- */
.page-about .matrix-panel {
  padding: clamp(20px, 4vw, 36px);
  border-radius: var(--radius);
  border-left: 2px solid var(--orange);
}

.page-about .matrix-panel p {
  margin: 0 0 14px;
  max-width: 60ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--about-soft-text);
}

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

.page-about .matrix-panel .mono {
  color: var(--cyan);
  letter-spacing: 0.03em;
}

.page-about .matrix-panel a {
  color: var(--orange-soft);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 178, 122, 0.45);
}

.page-about .matrix-panel a:hover {
  color: var(--paper);
  border-bottom-color: var(--orange);
}

/* ---------- 下一步 ---------- */
.page-about .next-list {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .next-list li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 4px 16px;
  padding: 18px 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .next-list li:last-child {
  border-bottom: 1px solid var(--line-soft);
}

.page-about .next-list__idx {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--orange);
  padding-top: 4px;
}

.page-about .next-list__title {
  display: block;
  font-size: 15.5px;
  font-weight: 700;
  color: var(--paper);
  line-height: 1.5;
}

.page-about .next-list li p {
  margin: 6px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--about-soft-text);
  max-width: 56ch;
}

.page-about .next-list a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(51, 214, 198, 0.45);
}

.page-about .next-list a:hover {
  color: var(--paper);
  border-bottom-color: var(--orange);
}

/* ---------- 行动区 ---------- */
.page-about .about-cta {
  margin-top: clamp(36px, 6vw, 72px);
  padding: clamp(20px, 4vw, 36px);
  display: grid;
  gap: 18px;
  border: 1px solid var(--line-soft);
  border-top: 2px solid var(--orange);
  border-radius: var(--radius);
  background: linear-gradient(135deg, rgba(30, 51, 88, 0.9), rgba(10, 18, 32, 0.96));
}

.page-about .about-cta__title {
  margin: 0;
  font-family: var(--ff-display);
  font-size: clamp(18px, 2.4vw, 24px);
  line-height: 1.35;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-cta__sub {
  margin: 8px 0 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--muted);
  max-width: 44ch;
}

.page-about .about-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-cta__links .btn:focus-visible {
  outline: 2px solid var(--orange);
  outline-offset: 2px;
}

/* ---------- 断点 ---------- */
@media (min-width: 720px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .origin-grid {
    grid-template-columns: minmax(0, 200px) minmax(0, 1fr);
    gap: clamp(24px, 4vw, 48px);
  }

  .page-about .tl-node--offset {
    padding-left: clamp(34px, 8vw, 96px);
  }

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

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    align-items: end;
  }

  .page-about .team-grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.85fr);
    align-items: start;
    gap: clamp(24px, 3.5vw, 44px);
  }

  .page-about .trust-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.72fr);
    align-items: start;
    gap: clamp(24px, 3.5vw, 44px);
  }
}

@media (min-width: 1024px) {
  .page-about .about-body {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 104px;
    align-self: start;
  }
}

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