.page-about {
  --about-rule: 1px solid rgba(35, 44, 92, .9);
  --about-soft: rgba(195, 203, 221, .72);
  background: var(--ink);
  color: var(--white);
  overflow-x: hidden;
}

/* ---------- 首屏框景 ---------- */
.page-about .about-hero {
  padding: calc(var(--header-h) + clamp(36px, 7vw, 96px)) var(--pad) clamp(28px, 4vw, 56px);
}

.page-about .about-hero-inner {
  position: relative;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: clamp(24px, 3.6vw, 56px);
  border: 1px solid var(--rail);
  background:
    linear-gradient(180deg, rgba(22, 30, 69, .62) 0%, rgba(11, 16, 48, .18) 100%);
}

.page-about .about-hero-inner::before,
.page-about .about-hero-inner::after {
  content: "";
  position: absolute;
  width: 14px;
  height: 14px;
  border: 2px solid var(--violet);
  pointer-events: none;
}

.page-about .about-hero-inner::before {
  top: -2px;
  left: -2px;
  border-right: 0;
  border-bottom: 0;
}

.page-about .about-hero-inner::after {
  bottom: -2px;
  right: -2px;
  border-left: 0;
  border-top: 0;
}

.page-about .hero-title {
  font-family: var(--font-display);
  font-size: clamp(32px, 5.4vw, 74px);
  line-height: 1.04;
  letter-spacing: -0.02em;
  font-weight: 800;
  margin: 18px 0 0;
  max-width: 20ch;
  color: var(--white);
}

.page-about .hero-lede {
  font-family: var(--font-serif);
  font-size: clamp(16.5px, 1.5vw, 20px);
  line-height: 1.78;
  color: var(--silver);
  margin: clamp(18px, 2.4vw, 28px) 0 0;
  max-width: 62ch;
}

.page-about .hero-facts {
  list-style: none;
  margin: clamp(28px, 3.6vw, 44px) 0 0;
  padding: clamp(20px, 2.4vw, 28px) 0 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px 24px;
  border-top: var(--about-rule);
}

.page-about .fact-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(21px, 2.6vw, 30px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--white);
}

.page-about .fact-label {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--about-soft);
}

.page-about .hero-ticks {
  height: 10px;
  margin-top: clamp(24px, 3vw, 36px);
  background-image: repeating-linear-gradient(90deg, rgba(124, 92, 255, .85) 0 1px, transparent 1px 14px);
  opacity: .5;
}

/* ---------- 主体外壳与索引轨道 ---------- */
.page-about .about-shell {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 var(--pad) clamp(48px, 7vw, 112px);
}

.page-about .about-rail {
  position: sticky;
  top: var(--header-h);
  z-index: 6;
  margin-left: calc(var(--pad) * -1);
  margin-right: calc(var(--pad) * -1);
  padding: 0 var(--pad);
  background: rgba(11, 16, 48, .94);
  border-bottom: var(--about-rule);
  overflow-x: auto;
  overflow-y: hidden;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.page-about .about-rail::-webkit-scrollbar {
  display: none;
}

.page-about .rail-nav {
  display: flex;
  gap: 22px;
  padding: 13px 0;
  white-space: nowrap;
}

.page-about .rail-link {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .05em;
  color: rgba(195, 203, 221, .6);
  text-decoration: none;
  transition: color 200ms var(--ease);
}

.page-about .rail-link:hover,
.page-about .rail-link:focus-visible {
  color: var(--white);
}

.page-about .rail-link[aria-current="true"] {
  color: var(--violet);
}

/* ---------- 章节基础 ---------- */
.page-about .section {
  padding: clamp(44px, 6.4vw, 96px) 0;
  border-bottom: var(--about-rule);
}

.page-about .section:last-of-type {
  border-bottom: 0;
  padding-bottom: clamp(24px, 3vw, 40px);
}

.page-about .section-head {
  display: grid;
  gap: 12px;
  margin-bottom: clamp(24px, 3vw, 40px);
}

.page-about .section-no {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(24px, 3vw, 40px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0;
  color: var(--violet);
}

.page-about .section-title {
  font-family: var(--font-display);
  font-size: clamp(26px, 4vw, 54px);
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.02em;
  margin: 0;
  max-width: 24ch;
  color: var(--white);
}

.page-about .section-lede {
  font-family: var(--font-serif);
  font-size: clamp(16px, 1.4vw, 19px);
  line-height: 1.72;
  margin: 0;
  max-width: 58ch;
  color: var(--silver);
}

.page-about .prose {
  max-width: 68ch;
  font-size: 16.5px;
  line-height: 1.78;
  color: var(--silver);
}

.page-about .prose p {
  margin: 0 0 1.1em;
}

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

.page-about .prose a {
  color: var(--violet);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}

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

.page-about .media-caption {
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: .02em;
  color: rgba(195, 203, 221, .68);
  margin-top: 10px;
}

/* ---------- 起源章节 ---------- */
.page-about .intro-grid {
  display: grid;
  gap: clamp(24px, 4vw, 52px);
}

.page-about .lane-diagram {
  display: block;
  width: 100%;
  max-width: 420px;
  height: auto;
  margin-top: clamp(26px, 3.4vw, 44px);
  padding: 16px;
  border: 1px solid var(--rail);
  background: rgba(22, 30, 69, .5);
}

/* ---------- 质保章节 ---------- */
.page-about .warranty-split {
  display: grid;
  gap: 18px;
  margin-top: clamp(24px, 3vw, 40px);
}

.page-about .warranty-card {
  position: relative;
  padding: clamp(22px, 2.8vw, 34px);
  border: 1px solid var(--rail);
  border-top-width: 4px;
  background: var(--panel);
  overflow: hidden;
}

.page-about .warranty-card--amber {
  border-top-color: var(--amber);
}

.page-about .warranty-card--celadon {
  border-top-color: var(--celadon);
}

.page-about .warranty-card::after {
  content: attr(data-years);
  position: absolute;
  right: 14px;
  top: 6px;
  font-family: var(--font-mono);
  font-size: clamp(54px, 8vw, 92px);
  font-weight: 700;
  line-height: 1;
  opacity: .08;
  pointer-events: none;
}

.page-about .warranty-card h3 {
  font-family: var(--font-display);
  font-size: clamp(21px, 2.4vw, 30px);
  font-weight: 800;
  letter-spacing: -0.01em;
  line-height: 1.15;
  margin: 14px 0 12px;
  color: var(--white);
}

.page-about .warranty-card ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .warranty-card li {
  position: relative;
  padding-left: 18px;
  margin-bottom: 10px;
  font-size: 15.5px;
  line-height: 1.72;
  color: var(--silver);
}

.page-about .warranty-card li:last-child {
  margin-bottom: 0;
}

.page-about .warranty-card li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .66em;
  width: 9px;
  height: 2px;
}

.page-about .warranty-card--amber li::before {
  background: var(--amber);
}

.page-about .warranty-card--celadon li::before {
  background: var(--celadon);
}

.page-about .warranty-notes {
  margin-top: clamp(20px, 2.6vw, 34px);
}

.page-about .disclosure-label {
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 600;
  color: var(--white);
}

/* ---------- 物流章节 ---------- */
.page-about .logistics-grid {
  display: grid;
  gap: clamp(28px, 4vw, 56px);
}

.page-about .stat-stack {
  border-top: var(--about-rule);
}

.page-about .stat {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding: 16px 0;
  border-bottom: var(--about-rule);
}

.page-about .stat-num {
  flex: 0 0 auto;
  min-width: 3.4ch;
  font-family: var(--font-mono);
  font-size: clamp(24px, 2.8vw, 36px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--cyan);
}

.page-about .stat-label {
  font-size: 14.5px;
  line-height: 1.6;
  color: var(--silver);
}

/* ---------- 团队章节 ---------- */
.page-about .team-grid {
  display: grid;
  gap: clamp(24px, 4vw, 52px);
  align-items: start;
}

.page-about .team-roster {
  display: grid;
  margin-top: clamp(28px, 3.4vw, 48px);
  border-top: var(--about-rule);
}

.page-about .roster-item {
  padding: 22px 0;
  border-bottom: var(--about-rule);
}

.page-about .roster-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(28px, 3.4vw, 44px);
  font-weight: 700;
  line-height: 1;
  color: var(--white);
}

.page-about .roster-title {
  font-family: var(--font-display);
  font-size: clamp(17px, 1.7vw, 21px);
  font-weight: 800;
  letter-spacing: -0.01em;
  margin: 12px 0 8px;
  color: var(--white);
}

.page-about .roster-desc {
  font-size: 15px;
  line-height: 1.7;
  margin: 0;
  color: var(--silver);
  max-width: 42ch;
}

/* ---------- 时间轴 ---------- */
.page-about .timeline {
  display: grid;
  gap: 0;
}

.page-about .tl-node {
  position: relative;
  padding: 22px 0 22px 26px;
  border-left: 1px solid var(--rail);
}

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

.page-about .tl-mark {
  position: absolute;
  left: -5px;
  top: 27px;
  width: 9px;
  height: 9px;
  background: var(--violet);
  transition: transform 220ms var(--ease), background-color 220ms var(--ease);
}

.page-about .tl-when {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--violet);
  margin-bottom: 8px;
}

.page-about .tl-title {
  font-family: var(--font-display);
  font-size: clamp(17px, 1.7vw, 21px);
  font-weight: 800;
  letter-spacing: -0.01em;
  line-height: 1.25;
  margin: 0 0 8px;
  color: var(--white);
}

.page-about .tl-desc {
  font-size: 14.5px;
  line-height: 1.7;
  margin: 0;
  color: var(--silver);
  transition: color 220ms var(--ease);
}

/* ---------- 结尾入口 ---------- */
.page-about .about-cta {
  border-top: var(--about-rule);
  padding: clamp(44px, 6vw, 88px) var(--pad) clamp(52px, 8vw, 112px);
}

.page-about .cta-inner {
  max-width: var(--wrap);
  margin: 0 auto;
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  align-items: end;
}

.page-about .cta-title {
  font-family: var(--font-display);
  font-size: clamp(24px, 3.2vw, 42px);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.1;
  margin: 10px 0 0;
  max-width: 20ch;
  color: var(--white);
}

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

/* ---------- 窄屏与宽屏适配 ---------- */
@media (min-width: 720px) {
  .page-about .hero-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (min-width: 860px) {
  .page-about .intro-grid {
    grid-template-columns: minmax(0, 1fr) minmax(240px, 320px);
    align-items: start;
  }

  .page-about .team-grid {
    grid-template-columns: minmax(0, 1fr) minmax(240px, 330px);
  }

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

  .page-about .roster-item {
    border-bottom: 0;
    border-right: var(--about-rule);
    padding: 26px 24px 0 0;
  }

  .page-about .roster-item:last-child {
    border-right: 0;
    padding-right: 0;
  }

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

@media (min-width: 900px) {
  .page-about .logistics-grid {
    grid-template-columns: minmax(0, 1.35fr) minmax(240px, 1fr);
    align-items: start;
  }

  .page-about .timeline {
    grid-template-columns: repeat(5, minmax(0, 1fr));
    margin-top: clamp(30px, 4vw, 52px);
  }

  .page-about .tl-node {
    border-left: 0;
    border-top: var(--about-rule);
    padding: 30px 18px 0 0;
  }

  .page-about .tl-node:last-child {
    padding-right: 0;
  }

  .page-about .tl-mark {
    left: 0;
    top: -5px;
    box-shadow: 0 0 0 4px var(--ink);
  }
}

@media (min-width: 1080px) {
  .page-about .about-shell {
    display: grid;
    grid-template-columns: 96px minmax(0, 1fr);
    column-gap: clamp(24px, 4vw, 64px);
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 36px);
    margin: 0;
    padding: clamp(44px, 6.4vw, 96px) 0 0;
    background: transparent;
    border-bottom: 0;
    overflow: visible;
  }

  .page-about .rail-nav {
    display: block;
    padding: 0;
    white-space: normal;
  }

  .page-about .rail-link {
    display: block;
    padding: 10px 0;
    font-size: 12px;
    line-height: 1.45;
    letter-spacing: .02em;
  }

  .page-about .rail-link[aria-current="true"] {
    box-shadow: inset 2px 0 0 var(--violet);
    padding-left: 10px;
  }

  .page-about .hero-title {
    max-width: 18ch;
  }
}

@media (hover: hover) {
  .page-about .tl-node:hover .tl-mark {
    transform: scale(1.4);
    background: var(--cyan);
  }

  .page-about .tl-node:hover .tl-desc {
    color: var(--white);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tl-mark,
  .page-about .tl-desc,
  .page-about .rail-link {
    transition: none;
  }
}