/* 品牌总览 · 档案式长文 */
.page-about {
  background: var(--ink-900);
  color: var(--text);
  font-family: var(--font-body);
  overflow-x: hidden;
}

/* ── 头部档案带 ── */
.page-about .about-head {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding: calc(var(--header-h) + clamp(2.25rem, 7vw, 4.5rem)) 0 clamp(2rem, 5vw, 3.25rem);
  border-bottom: 1px solid var(--line);
}

.page-about .head-media {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.page-about .head-media img {
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
  object-position: center 42%;
  opacity: 0.34;
}

.page-about .about-head::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  background:
    radial-gradient(120% 90% at 12% 0%, rgba(55, 231, 211, 0.14), transparent 58%),
    linear-gradient(180deg, rgba(6, 12, 24, 0.7) 0%, rgba(6, 12, 24, 0.88) 55%, var(--ink-900) 100%);
}

.page-about .about-head .wrap {
  position: relative;
  z-index: 2;
}

.page-about .about-head .display {
  max-width: 22ch;
  margin: 0.7rem 0 0;
}

.page-about .about-head .lede {
  max-width: 58ch;
  margin-top: 1rem;
  color: var(--muted);
}

.page-about .head-facts {
  list-style: none;
  margin: clamp(1.75rem, 4vw, 2.5rem) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .head-facts li {
  background: rgba(21, 39, 66, 0.72);
  padding: 0.85rem 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.page-about .fact-num {
  font-family: var(--font-mono);
  font-size: 1.35rem;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--cyan);
}

.page-about .fact-key {
  font-size: 0.76rem;
  letter-spacing: 0.16em;
  color: var(--muted);
}

/* ── 滚动信息条 ── */
.page-about .ticker {
  background: var(--ink-800);
  border-bottom: 1px solid var(--line);
}

/* ── 本页目录 ── */
.page-about .doc-index {
  padding-top: clamp(2rem, 5vw, 3.25rem);
}

.page-about .index-list {
  list-style: none;
  margin: 1rem 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .index-link {
  display: flex;
  align-items: baseline;
  gap: 0.8rem;
  padding: 0.72rem 0.6rem;
  background: var(--ink-900);
  color: var(--text);
  font-size: 0.92rem;
  text-decoration: none;
  transition: background 180ms var(--ease), color 180ms var(--ease);
}

.page-about .index-num {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  color: var(--ember);
  transition: color 180ms var(--ease);
}

.page-about .index-link:hover,
.page-about .index-link:focus-visible {
  background: var(--ink-700);
  color: var(--cyan);
}

.page-about .index-link:hover .index-num,
.page-about .index-link:focus-visible .index-num {
  color: var(--cyan);
}

/* ── 章节主体 ── */
.page-about .chapters {
  padding-bottom: clamp(2.5rem, 6vw, 4rem);
}

.page-about .chapter {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.1rem;
  padding: clamp(2.25rem, 5vw, 3.5rem) 0;
  scroll-margin-top: calc(var(--header-h) + 1.5rem);
}

.page-about .chapter + .chapter {
  border-top: 1px solid var(--line);
}

.page-about .chapter-rail {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.page-about .chapter-num {
  font-family: var(--font-mono);
  font-size: clamp(1.7rem, 4.6vw, 2.2rem);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--ember);
  text-decoration: none;
  transition: color 180ms var(--ease);
}

.page-about .chapter-num:hover,
.page-about .chapter-num:focus-visible {
  color: var(--gold);
}

.page-about .chapter-rule {
  flex: 1 1 auto;
  height: 1px;
  background: linear-gradient(90deg, var(--ember), rgba(228, 87, 46, 0));
}

.page-about .chapter-body {
  max-width: 62ch;
  min-width: 0;
}

.page-about .chapter-title {
  margin: 0 0 0.9rem;
  letter-spacing: -0.015em;
}

.page-about .chapter-body > p {
  margin: 0 0 0.95rem;
  color: var(--muted);
  line-height: 1.85;
}

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

.page-about .inline-link {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
  transition: border-color 180ms var(--ease), color 180ms var(--ease);
}

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

/* ── 右侧口径注释 ── */
.page-about .chapter-note {
  border-left: 2px solid var(--line);
  padding-left: 0.9rem;
  font-size: 0.82rem;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .note-key {
  margin: 0 0 0.35rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.2em;
  color: var(--gold);
}

.page-about .note-val {
  margin: 0;
}

.page-about .note-val b {
  font-family: var(--font-mono);
  font-weight: 500;
  color: var(--text);
}

/* ── 栏目卡片 ── */
.page-about .catalog {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.9rem;
  margin-top: 1.5rem;
}

.page-about .catalog-card {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  background: var(--ink-700);
  border: 1px solid var(--line);
  padding: 1.1rem 1.15rem 1rem;
  transition: border-color 180ms var(--ease), background 180ms var(--ease);
}

.page-about .catalog-card:hover,
.page-about .catalog-card:focus-within {
  border-color: var(--cyan);
  background: var(--ink-800);
}

.page-about .card-label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.2em;
  color: var(--cyan);
}

.page-about .cat-title {
  margin: 0;
  font-size: 1.14rem;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.page-about .cat-desc {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .card-foot {
  margin: auto 0 0;
  padding-top: 0.7rem;
  border-top: 1px dashed var(--line);
  display: flex;
  flex-wrap: wrap;
  gap: 0.3rem 1rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--muted);
}

.page-about .card-foot .freq {
  transition: color 180ms var(--ease);
}

.page-about .catalog-card:hover .freq,
.page-about .catalog-card:focus-within .freq {
  color: var(--cyan);
}

.page-about .cat-link {
  align-self: flex-start;
  margin-top: 0.35rem;
  font-size: 0.86rem;
  font-weight: 500;
  color: var(--cyan);
  text-decoration: none;
  padding-bottom: 2px;
  border-bottom: 1px solid var(--line);
  transition: border-color 180ms var(--ease), color 180ms var(--ease);
}

.page-about .cat-link:hover,
.page-about .cat-link:focus-visible {
  color: var(--text);
  border-bottom-color: var(--ember);
}

/* ── 图注 ── */
.page-about .chapter-figure {
  margin: 1.5rem 0 0;
}

.page-about .chapter-figure .media {
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--ink-800);
}

.page-about .chapter-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .media-cap {
  margin: 0.55rem 0 0;
  font-size: 0.74rem;
  letter-spacing: 0.05em;
  line-height: 1.7;
  color: var(--muted);
}

/* ── 四道工序 ── */
.page-about .flow {
  list-style: none;
  margin: 1.5rem 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.15rem;
}

.page-about .flow-step {
  position: relative;
  padding-top: 1.6rem;
  border-top: 1px solid var(--line);
}

.page-about .flow-step::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: 38px;
  height: 1px;
  background: var(--ember);
}

.page-about .flow-num {
  display: block;
  margin-bottom: 0.5rem;
  font-family: var(--font-mono);
  font-size: 1.5rem;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--ember);
}

.page-about .flow-title {
  margin: 0 0 0.35rem;
  font-size: 1rem;
  font-weight: 700;
}

.page-about .flow-text {
  margin: 0;
  font-size: 0.87rem;
  line-height: 1.78;
  color: var(--muted);
}

/* ── 运行脉络 ── */
.page-about .timeline {
  list-style: none;
  margin: 1.5rem 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .tl-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.3rem;
  padding: 1.05rem 0.9rem;
  background: var(--ink-900);
  transition: background 180ms var(--ease), box-shadow 180ms var(--ease);
  box-shadow: inset 2px 0 0 transparent;
}

.page-about .tl-item:hover {
  background: var(--ink-800);
  box-shadow: inset 2px 0 0 var(--cyan);
}

.page-about .tl-stage {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.18em;
  color: var(--gold);
}

.page-about .tl-title {
  margin: 0;
  font-size: 1.02rem;
  font-weight: 700;
}

.page-about .tl-text {
  margin: 0.35rem 0 0;
  font-size: 0.87rem;
  line-height: 1.78;
  color: var(--muted);
}

.page-about .tl-meta {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--muted);
}

/* ── 团队 ── */
.page-about .team-bar {
  display: flex;
  height: 10px;
  margin-top: 1.6rem;
  border: 1px solid var(--line);
}

.page-about .team-seg {
  display: block;
  height: 100%;
}

.page-about .team-seg--edit {
  width: 50%;
  background: linear-gradient(90deg, var(--cyan-deep), var(--cyan));
}

.page-about .team-seg--ops {
  width: 33.33%;
  background: var(--gold);
}

.page-about .team-seg--ux {
  width: 16.67%;
  background: var(--ember);
}

.page-about .team-list {
  list-style: none;
  margin: 1.35rem 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.15rem;
}

.page-about .team-item {
  border-top: 2px solid var(--line);
  padding-top: 0.85rem;
}

.page-about .team-item--edit {
  border-top-color: var(--cyan);
}

.page-about .team-item--ops {
  border-top-color: var(--gold);
}

.page-about .team-item--ux {
  border-top-color: var(--ember);
}

.page-about .team-role {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  color: var(--muted);
}

.page-about .team-count {
  display: block;
  font-family: var(--font-mono);
  font-size: 2rem;
  line-height: 1.15;
  color: var(--text);
}

.page-about .team-text {
  margin: 0.5rem 0 0;
  font-size: 0.87rem;
  line-height: 1.78;
  color: var(--muted);
}

/* ── 折叠条目 ── */
.page-about .acc {
  display: grid;
  gap: 0.6rem;
  margin-top: 1.5rem;
}

.page-about .acc-item {
  background: var(--ink-800);
  border: 1px solid var(--line);
  transition: border-color 180ms var(--ease);
}

.page-about .acc-item.is-open {
  border-color: var(--gold);
}

.page-about .acc-trigger {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 1.1rem;
  background: none;
  border: 0;
  color: var(--text);
  font-family: inherit;
  font-size: 0.96rem;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
}

.page-about .acc-trigger::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--cyan);
  transition: color 180ms var(--ease);
}

.page-about .acc-item.is-open .acc-trigger::after {
  content: "–";
  color: var(--gold);
}

.page-about .acc-panel {
  padding: 0 1.1rem 1.1rem;
  font-size: 0.88rem;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .acc-panel p {
  margin: 0;
}

.page-about .doc-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin: 1.35rem 0 0;
}

.page-about .doc-link {
  display: inline-block;
  padding: 0.4rem 0.85rem;
  font-size: 0.82rem;
  color: var(--text);
  text-decoration: none;
  border: 1px solid var(--line);
  background: var(--ink-700);
  transition: border-color 180ms var(--ease), color 180ms var(--ease);
}

.page-about .doc-link:hover,
.page-about .doc-link:focus-visible {
  border-color: var(--cyan);
  color: var(--cyan);
}

/* ── 页尾引导 ── */
.page-about .about-cta {
  background: var(--ink-800);
  border-top: 1px solid var(--line);
}

.page-about .about-cta-inner {
  padding: clamp(2rem, 5vw, 3rem) 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.25rem;
}

.page-about .cta-title {
  margin: 0;
  font-size: clamp(1.35rem, 2.8vw, 1.85rem);
  font-weight: 800;
  letter-spacing: -0.015em;
}

.page-about .cta-text {
  margin: 0.6rem 0 0;
  max-width: 52ch;
  font-size: 0.92rem;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

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

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

  .page-about .catalog {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }

  .page-about .catalog-card--wide {
    grid-column: span 4;
  }

  .page-about .catalog-card--narrow {
    grid-column: span 2;
  }

  .page-about .flow {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1.4rem;
  }

  .page-about .team-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.5rem;
  }

  .page-about .tl-item {
    grid-template-columns: 104px minmax(0, 1fr);
    align-items: baseline;
    column-gap: 1rem;
    padding: 1.15rem 1rem;
  }

  .page-about .tl-meta {
    grid-column: 2;
  }
}

@media (min-width: 1000px) {
  .page-about .chapter {
    grid-template-columns: 64px minmax(0, 1fr) 220px;
    column-gap: clamp(1.25rem, 2.8vw, 2.5rem);
  }

  .page-about .chapter-rail {
    flex-direction: column;
    align-items: flex-start;
    align-self: start;
    gap: 0.8rem;
    position: sticky;
    top: calc(var(--header-h) + 1.5rem);
  }

  .page-about .chapter-rule {
    width: 1px;
    flex: 1 1 auto;
    min-height: 72px;
    background: linear-gradient(180deg, var(--ember), rgba(228, 87, 46, 0));
  }

  .page-about .chapter-note {
    grid-column: 3;
    align-self: start;
  }

  .page-about .chapter-figure--wide {
    grid-column: 2 / -1;
    margin-top: 2rem;
  }

  .page-about .flow {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 1.25rem;
  }

  .page-about .flow-step::after {
    content: "";
    position: absolute;
    top: -4px;
    right: -0.65rem;
    width: 8px;
    height: 8px;
    border-top: 1px solid var(--ember);
    border-right: 1px solid var(--ember);
    transform: rotate(45deg);
  }

  .page-about .flow-step:last-child::after {
    display: none;
  }

  .page-about .about-cta-inner {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 2rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .catalog-card,
  .page-about .tl-item,
  .page-about .index-link,
  .page-about .cat-link,
  .page-about .inline-link,
  .page-about .acc-item,
  .page-about .doc-link,
  .page-about .chapter-num {
    transition: none;
  }
}