/* ============================================================
   page-about · 品牌文化
   作用域：.page-about
   ============================================================ */

.page-about {
  --about-rail: clamp(16px, 3vw, 32px);
  --about-gap: clamp(24px, 4vw, 56px);
  display: block;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb.wrap {
  padding-top: clamp(16px, 3vw, 26px);
  padding-bottom: 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-top: clamp(28px, 5vw, 56px);
  padding-bottom: clamp(32px, 5vw, 64px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background:
    radial-gradient(circle at 82% 14%, rgba(34, 245, 200, 0.16), transparent 58%),
    radial-gradient(circle at 8% 88%, rgba(255, 182, 39, 0.08), transparent 52%),
    linear-gradient(180deg, rgba(12, 31, 25, 0.78), rgba(6, 11, 10, 0) 78%);
}

.page-about .about-hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  align-items: end;
}

.page-about .about-hero-copy h1 {
  margin: 12px 0 18px;
  font-family: var(--font-head);
  font-size: clamp(30px, 5.6vw, 52px);
  font-weight: 800;
  line-height: 1.14;
  letter-spacing: -0.01em;
  color: var(--text);
  text-wrap: balance;
}

.page-about .about-hero-copy p {
  margin: 0 0 14px;
  max-width: 56ch;
}

.page-about .about-hero-copy .serif-lead {
  margin-bottom: 18px;
  font-size: clamp(17px, 2vw, 20px);
  line-height: 1.7;
  color: var(--neon-soft);
}

.page-about .about-hero-note {
  position: relative;
  margin-top: 22px;
  padding: 12px 0 12px 18px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
  border-left: var(--bw) solid var(--neon);
}

.page-about .about-hero-media {
  margin: 0;
  position: relative;
  border: var(--bw) solid var(--line);
  background: linear-gradient(150deg, var(--pitch), var(--ink));
  box-shadow: var(--shadow-hard);
  overflow: hidden;
}

.page-about .about-hero-media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(6, 11, 10, 0) 42%, rgba(6, 11, 10, 0.72) 100%);
  pointer-events: none;
}

.page-about .about-hero-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  filter: saturate(0.92) contrast(1.06);
}

/* ---------- 章节索引条 ---------- */
.page-about .about-toc {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: clamp(8px, 2vw, 18px);
  padding: 12px 0 12px;
  border-top: var(--bw) solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .about-toc-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-toc-list {
  display: flex;
  flex-wrap: nowrap;
  gap: 8px;
  margin: 0;
  padding: 0 0 4px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-toc-link {
  display: inline-block;
  white-space: nowrap;
  padding: 7px 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
  text-decoration: none;
  border: 1px solid var(--line);
  background: var(--step);
  transition: color 200ms var(--ease), border-color 200ms var(--ease), background 200ms var(--ease);
}

.page-about .about-toc-link:hover,
.page-about .about-toc-link:focus-visible,
.page-about .about-toc-link.is-active {
  color: var(--ink);
  background: var(--neon);
  border-color: var(--neon);
}

/* ---------- 两栏布局 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  padding-top: clamp(28px, 5vw, 56px);
  padding-bottom: clamp(40px, 6vw, 88px);
}

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

/* ---------- 章节通用 ---------- */
.page-about .about-chapter {
  padding: clamp(24px, 4vw, 40px) 0;
  border-top: 1px solid var(--line);
}

.page-about .about-chapter:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .about-chapter-head {
  margin-bottom: 18px;
}

.page-about .about-chapter-head h2 {
  margin: 8px 0 0;
  font-family: var(--font-head);
  font-size: clamp(22px, 3.2vw, 32px);
  font-weight: 800;
  line-height: 1.24;
  letter-spacing: -0.01em;
  color: var(--text);
}

.page-about .about-num {
  display: inline-block;
  margin-right: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--amber);
  letter-spacing: 0.08em;
}

.page-about .about-chapter p {
  margin: 0 0 14px;
  max-width: 66ch;
  line-height: 1.78;
  color: var(--text);
}

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

/* ---------- 要点条 ---------- */
.page-about .about-points {
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
  border-top: var(--bw) solid var(--line);
}

.page-about .about-points li {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 4px;
  padding: 14px 0 14px 16px;
  font-size: 15px;
  line-height: 1.72;
  color: var(--text);
  border-bottom: 1px solid var(--line);
  border-left: 3px solid transparent;
  transition: border-color 220ms var(--ease), background 220ms var(--ease);
}

.page-about .about-points li:hover {
  border-left-color: var(--neon);
  background: rgba(34, 245, 200, 0.05);
}

.page-about .about-points-key {
  font-family: var(--font-head);
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--neon);
}

/* ---------- 配图 ---------- */
.page-about .about-figure {
  margin: 24px 0 0;
  padding: 0;
  border: var(--bw) solid var(--line);
  background: linear-gradient(160deg, var(--step), var(--ink));
  box-shadow: var(--shadow-hard);
  overflow: hidden;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.9) contrast(1.05);
}

.page-about .about-figure--wide img {
  aspect-ratio: 3 / 2;
}

.page-about .about-figure--tall img {
  aspect-ratio: 4 / 3;
}

.page-about .about-figure figcaption {
  padding: 12px 16px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
  border-top: 1px solid var(--line);
}

/* ---------- 发展轨迹 SVG ---------- */
.page-about .about-track {
  margin: 26px 0 4px;
  padding: 0 4px;
}

.page-about .about-track svg {
  display: block;
  width: 100%;
  height: auto;
  max-height: 132px;
  overflow: visible;
}

.page-about .about-track-line {
  stroke: var(--neon);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
  opacity: 0.85;
  filter: drop-shadow(0 0 6px rgba(34, 245, 200, 0.35));
}

.page-about .about-track-dot {
  fill: var(--ink);
  stroke: var(--neon);
  stroke-width: 3;
}

.page-about .about-track-dot:last-child {
  fill: var(--amber);
  stroke: var(--amber);
  filter: drop-shadow(0 0 8px rgba(255, 182, 39, 0.55));
}

/* ---------- 时间线节点 ---------- */
.page-about .about-nodes {
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-node {
  border-bottom: 1px solid var(--line);
}

.page-about .about-node summary {
  display: grid;
  gap: 4px;
  padding: 16px 32px 16px 18px;
  position: relative;
  cursor: pointer;
  list-style: none;
  transition: background 220ms var(--ease);
}

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

.page-about .about-node summary::after {
  content: "+";
  position: absolute;
  right: 10px;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--neon);
  line-height: 1;
}

.page-about .about-node[open] summary::after {
  content: "−";
  color: var(--amber);
}

.page-about .about-node summary:hover,
.page-about .about-node summary:focus-visible {
  background: rgba(34, 245, 200, 0.06);
}

.page-about .about-node-era {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--amber);
}

.page-about .about-node-title {
  font-family: var(--font-head);
  font-size: 16px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--text);
}

.page-about .about-node p {
  margin: 0;
  padding: 0 18px 16px 18px;
  font-size: 15px;
  line-height: 1.78;
  color: var(--muted);
}

/* ---------- 合作伙伴数据格 ---------- */
.page-about .about-partner-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 24px;
}

.page-about .about-partner-cell {
  padding: 20px 18px;
  border: var(--bw) solid var(--line);
  background: linear-gradient(150deg, var(--step), var(--pitch));
  box-shadow: var(--shadow-hard);
}

.page-about .about-partner-num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 44px;
  font-weight: 700;
  line-height: 1;
  color: var(--amber);
  letter-spacing: -0.02em;
}

.page-about .about-partner-label {
  margin: 10px 0 6px;
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--text);
}

.page-about .about-partner-desc {
  margin: 0;
  font-size: 13px;
  line-height: 1.72;
  color: var(--muted);
}

/* ---------- 三条底线 ---------- */
.page-about .about-rules {
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  counter-reset: about-rule;
}

.page-about .about-rule {
  position: relative;
  padding: 20px 0 20px 52px;
  border-top: 1px solid var(--line);
}

.page-about .about-rule:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .about-rule-index {
  position: absolute;
  left: 0;
  top: 18px;
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  color: var(--ink);
  background: var(--neon);
  box-shadow: 3px 3px 0 rgba(0, 0, 0, 0.5);
}

.page-about .about-rule h3 {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-size: 17px;
  font-weight: 800;
  letter-spacing: 0.01em;
  color: var(--text);
}

.page-about .about-rule p {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--muted);
}

.page-about .about-cta-line {
  margin-top: 22px;
  padding: 16px 18px;
  font-size: 15px;
  line-height: 1.78;
  color: var(--text);
  border-left: var(--bw) solid var(--amber);
  background: rgba(255, 182, 39, 0.07);
}

.page-about .about-inline-link {
  color: var(--neon);
  text-decoration: none;
  border-bottom: 1px solid rgba(34, 245, 200, 0.45);
  transition: color 180ms var(--ease), border-color 180ms var(--ease);
}

.page-about .about-inline-link:hover,
.page-about .about-inline-link:focus-visible {
  color: var(--neon-soft);
  border-bottom-color: var(--neon-soft);
}

/* ---------- 右栏规模卡片 ---------- */
.page-about .about-aside {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  align-content: start;
}

.page-about .about-stat {
  position: relative;
  padding: 20px 18px 18px;
  border: var(--bw) solid var(--line);
  border-left-width: 4px;
  border-left-color: var(--neon);
  background: linear-gradient(155deg, var(--step), var(--pitch));
  box-shadow: var(--shadow-hard);
  transition: border-left-color 260ms var(--ease), transform 260ms var(--ease), box-shadow 260ms var(--ease);
}

.page-about .about-stat:hover {
  transform: translate(-2px, -2px);
  box-shadow: 8px 8px 0 rgba(34, 245, 200, 0.16);
}

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

.page-about .about-stat--amber:hover {
  box-shadow: 8px 8px 0 rgba(255, 182, 39, 0.18);
}

.page-about .about-stat--flat {
  border-left-color: var(--line);
  background: linear-gradient(155deg, var(--pitch), var(--ink));
}

.page-about .about-stat-num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(38px, 7vw, 54px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--text);
  font-variant-numeric: tabular-nums;
}

.page-about .about-stat--amber .about-stat-num {
  color: var(--amber);
}

.page-about .about-stat-num sup {
  font-size: 0.42em;
  vertical-align: super;
  color: var(--amber);
}

.page-about .about-stat-unit {
  margin-left: 6px;
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--muted);
  vertical-align: middle;
}

.page-about .about-stat-label {
  margin: 10px 0 6px;
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--neon);
}

.page-about .about-stat--amber .about-stat-label {
  color: var(--amber);
}

.page-about .about-stat--flat .about-stat-label {
  color: var(--muted);
}

.page-about .about-stat-note {
  margin: 0;
  font-size: 13px;
  line-height: 1.72;
  color: var(--muted);
}

/* ---------- 收口数据带 ---------- */
.page-about .about-band {
  position: relative;
  border-top: var(--bw) solid var(--line);
  border-bottom: var(--bw) solid var(--line);
  background:
    repeating-linear-gradient(
      -45deg,
      rgba(30, 61, 51, 0.55) 0 10px,
      rgba(12, 31, 25, 0.55) 10px 20px
    ),
    linear-gradient(120deg, var(--pitch), var(--ink) 70%);
}

.page-about .about-band-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  padding-top: clamp(24px, 4vw, 40px);
  padding-bottom: clamp(24px, 4vw, 40px);
}

.page-about .about-band-lead {
  margin: 0;
  max-width: 48ch;
  font-family: var(--font-serif);
  font-size: clamp(17px, 2.2vw, 21px);
  line-height: 1.7;
  color: var(--text);
}

.page-about .about-band-facts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
  padding-top: 18px;
}

.page-about .about-band-facts li {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .about-band-key {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--muted);
}

.page-about .about-band-val {
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--neon);
  font-variant-numeric: tabular-nums;
}

/* ---------- 焦点可见性 ---------- */
.page-about a:focus-visible,
.page-about summary:focus-visible {
  outline: 2px solid var(--amber);
  outline-offset: 3px;
}

/* ============================================================
   断点：640px 以上
   ============================================================ */
@media (min-width: 640px) {
  .page-about .about-toc {
    flex-direction: row;
    align-items: center;
    gap: 16px;
  }

  .page-about .about-toc-label {
    flex: 0 0 auto;
  }

  .page-about .about-toc-list {
    flex-wrap: wrap;
    overflow-x: visible;
    padding-bottom: 0;
  }

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

  .page-about .about-band-inner {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    align-items: start;
    gap: 32px;
  }

  .page-about .about-band-facts {
    border-top: 0;
    padding-top: 0;
  }
}

/* ============================================================
   断点：900px 以上 — 分栏与侧栏
   ============================================================ */
@media (min-width: 900px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: clamp(32px, 4vw, 64px);
  }

  .page-about .about-hero-media {
    align-self: center;
  }

  .page-about .about-layout {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: clamp(36px, 5vw, 72px);
  }

  .page-about .about-aside {
    position: sticky;
    top: 88px;
  }

  .page-about .about-points li {
    grid-template-columns: 108px minmax(0, 1fr);
    gap: 14px;
    align-items: baseline;
  }

  .page-about .about-rules {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0;
    border-top: var(--bw) solid var(--line);
    border-bottom: var(--bw) solid var(--line);
  }

  .page-about .about-rule {
    padding: 22px 18px 24px;
    border-top: 0;
    border-right: 1px solid var(--line);
  }

  .page-about .about-rule:last-child {
    border-right: 0;
    border-bottom: 0;
  }

  .page-about .about-rule-index {
    position: static;
    width: 36px;
    height: 36px;
    margin-bottom: 14px;
  }
}

/* ============================================================
   断点：1200px 以上
   ============================================================ */
@media (min-width: 1200px) {
  .page-about .about-chapter {
    padding: clamp(32px, 4vw, 52px) 0;
  }

  .page-about .about-figure {
    margin-left: 0;
    margin-right: 0;
  }
}

/* ============================================================
   减弱动效
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-stat,
  .page-about .about-toc-link,
  .page-about .about-points li,
  .page-about .about-node summary,
  .page-about .about-inline-link {
    transition: none;
  }

  .page-about .about-stat:hover {
    transform: none;
  }
}