.page-about {
  --about-soft: rgba(243, 237, 224, 0.78);
  --about-faint: rgba(243, 237, 224, 0.56);
  max-width: var(--max-width);
  margin-inline: auto;
  padding: 0 var(--gutter) clamp(48px, 7vw, 96px);
  color: var(--cream);
  font-family: var(--font-body);
  overflow-x: hidden;
}

.page-about .breadcrumb {
  padding: 18px 0 0;
  font-size: 12px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(24px, 4vw, 52px) 0 clamp(32px, 5vw, 60px);
  border-bottom: 1px solid var(--line-faint);
}

.page-about .pa-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--col-gap);
}

.page-about .hero-main {
  min-width: 0;
}

.page-about .eyebrow {
  color: var(--lime);
  margin: 0;
}

.page-about .hero-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.9rem, 6vw, 3.3rem);
  line-height: 1.12;
  letter-spacing: -0.01em;
  margin: 12px 0 18px;
  color: var(--cream);
}

.page-about .hero-lede {
  max-width: 58ch;
  color: var(--about-soft);
  font-size: 1rem;
  line-height: 1.75;
  margin: 0;
}

.page-about .hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .hero-readout {
  align-self: stretch;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px 16px;
  padding: 22px 20px;
  background: var(--ink-900);
  box-shadow: inset 0 0 0 1px var(--line-faint);
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, 0 100%);
}

.page-about .readout-item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-width: 0;
}

.page-about .readout-item .data-value {
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 4.4vw, 2rem);
  line-height: 1;
  color: var(--amber);
  letter-spacing: 0.02em;
}

.page-about .readout-item .data-label {
  font-size: 11px;
  line-height: 1.5;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

/* ---------- 长文骨架 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 48px);
  padding-top: clamp(28px, 4vw, 56px);
}

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

.page-about .about-toc {
  order: -1;
  min-width: 0;
}

.page-about .toc-title {
  margin: 0 0 10px;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .toc-list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
}

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

.page-about .toc-list .index-link {
  display: block;
  white-space: nowrap;
  padding: 6px 10px;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--about-soft);
  text-decoration: none;
  border: 1px solid var(--line-faint);
  background: var(--ink-900);
}

.page-about .toc-list .index-link:hover,
.page-about .toc-list .index-link:focus-visible {
  color: var(--ink-950);
  background: var(--lime);
  border-color: var(--lime);
}

/* ---------- 章节 ---------- */
.page-about .about-section {
  padding: clamp(28px, 4vw, 52px) 0;
  border-top: 1px solid var(--line-faint);
  scroll-margin-top: calc(var(--header-height) + 24px);
}

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

.page-about .section-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.42rem, 3.4vw, 2.1rem);
  line-height: 1.24;
  letter-spacing: -0.01em;
  margin: 8px 0 0;
  color: var(--cream);
}

.page-about .section-intro {
  max-width: 62ch;
  margin: 12px 0 0;
  color: var(--about-soft);
  line-height: 1.75;
}

.page-about .about-section p {
  color: var(--about-soft);
  line-height: 1.75;
}

/* ---------- 三条生产线 ---------- */
.page-about .line-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: 24px;
  background: var(--line-faint);
}

.page-about .line-card {
  background: var(--ink-950);
  padding: 22px 20px 24px;
}

.page-about .line-card .tag {
  color: var(--lime);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-size: 11px;
}

.page-about .line-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.04rem;
  line-height: 1.4;
  letter-spacing: 0.01em;
  margin: 10px 0 8px;
  color: var(--cream);
}

.page-about .line-card p {
  margin: 0;
  font-size: 0.94rem;
}

/* ---------- 编辑台 ---------- */
.page-about .desk-panel {
  padding: clamp(22px, 3.6vw, 40px);
  background: var(--ink-900);
}

.page-about .desk-head .section-intro {
  margin-top: 10px;
}

.page-about .desk-media {
  margin: 24px 0 0;
}

.page-about .media-frame img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .media-caption {
  margin-top: 10px;
  font-size: 12px;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .desk-columns {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(16px, 2.4vw, 24px);
  margin-top: 26px;
}

.page-about .desk-col {
  border-top: 2px solid var(--lime-deep);
  padding-top: 14px;
  min-width: 0;
}

.page-about .desk-col:nth-child(2) {
  border-top-color: var(--amber);
}

.page-about .desk-col:nth-child(3) {
  border-top-color: var(--muted);
}

.page-about .desk-col h3 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
  letter-spacing: 0.02em;
  margin: 0 0 8px;
  color: var(--cream);
}

.page-about .desk-col p {
  margin: 0;
  font-size: 0.92rem;
}

.page-about .desk-note {
  margin: 26px 0 0;
  padding-top: 18px;
  border-top: 1px dashed var(--line-faint);
  font-size: 0.92rem;
  color: var(--about-faint);
}

/* ---------- 版本时间线 ---------- */
.page-about .version-media {
  margin: 24px 0 0;
}

.page-about .version-rail {
  position: relative;
  list-style: none;
  margin: 30px 0 0;
  padding: 0 0 0 26px;
}

.page-about .version-rail::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 6px;
  bottom: 6px;
  width: 1px;
  background: linear-gradient(180deg, var(--lime), rgba(198, 255, 61, 0.12));
}

.page-about .version-item {
  position: relative;
}

.page-about .version-item + .version-item {
  margin-top: 18px;
}

.page-about .version-item::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 12px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--amber);
  box-shadow: 0 0 0 3px rgba(232, 180, 74, 0.16);
}

.page-about .version-node {
  background: var(--ink-900);
  padding: 14px 18px 16px;
  border-left: 1px solid var(--line-soft);
}

.page-about .version-node summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 12px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .version-tag {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  letter-spacing: 0.02em;
  color: var(--amber);
}

.page-about .version-era {
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .version-head {
  flex: 1 1 100%;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
  line-height: 1.45;
  color: var(--cream);
}

.page-about .version-node summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 1.05rem;
  color: var(--lime);
}

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

.page-about .version-node[open] {
  border-left-color: var(--lime);
}

.page-about .version-body {
  padding-top: 12px;
  max-width: 60ch;
}

.page-about .version-body p {
  margin: 0;
  font-size: 0.94rem;
}

/* ---------- 奶油引文页 ---------- */
.page-about .quote-slab {
  margin: clamp(28px, 4vw, 48px) 0;
  padding: clamp(28px, 5vw, 56px) clamp(22px, 4vw, 48px);
  background: var(--cream);
  color: var(--brown);
  clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 0 100%);
}

.page-about .quote-text {
  margin: 0;
  font-family: var(--font-editorial);
  font-size: clamp(1.28rem, 3.3vw, 1.95rem);
  line-height: 1.55;
  letter-spacing: 0.01em;
  color: var(--brown);
}

.page-about .quote-tag {
  margin: 18px 0 0;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(42, 29, 20, 0.58);
}

/* ---------- 覆盖范围 ---------- */
.page-about .coverage-copy {
  min-width: 0;
}

.page-about .coverage-copy p {
  margin: 12px 0 0;
}

.page-about .coverage-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 22px 0;
  padding: 0;
  list-style: none;
  background: var(--line-faint);
}

.page-about .coverage-list li {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 14px 16px;
  background: var(--ink-950);
  min-width: 0;
}

.page-about .coverage-list .data-value {
  font-family: var(--font-mono);
  font-size: 1.45rem;
  line-height: 1;
  color: var(--amber);
  letter-spacing: 0.02em;
}

.page-about .coverage-list .data-label {
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .coverage-media {
  margin: 24px 0 0;
  max-width: 360px;
}

/* ---------- 合作 ---------- */
.page-about .partner-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(16px, 2.4vw, 24px);
  margin-top: 24px;
}

.page-about .partner-card {
  padding: clamp(20px, 3vw, 32px);
  background: var(--ink-900);
}

.page-about .partner-card .tag {
  color: var(--amber);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.page-about .partner-card h3 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.1rem;
  line-height: 1.4;
  margin: 10px 0 10px;
  color: var(--cream);
}

.page-about .partner-card p {
  margin: 0;
  font-size: 0.94rem;
}

/* ---------- 做法 ---------- */
.page-about .principle-list {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 20px;
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .principle-list li {
  display: flex;
  gap: 14px;
  padding-top: 16px;
  border-top: 1px solid var(--line-faint);
}

.page-about .principle-num {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  letter-spacing: 0.02em;
  color: var(--amber);
  padding-top: 3px;
}

.page-about .principle-list h3 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
  line-height: 1.45;
  margin: 0 0 8px;
  color: var(--cream);
}

.page-about .principle-list p {
  margin: 0;
  font-size: 0.93rem;
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  margin-top: clamp(32px, 5vw, 64px);
  padding: clamp(24px, 4vw, 44px);
  background-color: var(--ink-900);
  background-image: repeating-linear-gradient(
    102deg,
    rgba(198, 255, 61, 0.07) 0 1px,
    transparent 1px 14px
  );
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 0 100%);
}

.page-about .about-cta p {
  max-width: 58ch;
  margin: 12px 0 0;
  color: var(--about-soft);
  line-height: 1.75;
}

.page-about .cta-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

/* ---------- 动画偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .toc-list .index-link {
    transition: none;
  }
}

/* ---------- 平板及以上 ---------- */
@media (min-width: 760px) {
  .page-about .line-grid {
    grid-template-columns: 1.1fr 0.9fr 1.1fr;
  }

  .page-about .desk-columns {
    grid-template-columns: 1.15fr 0.85fr 1fr;
  }

  .page-about .partner-grid {
    grid-template-columns: 1.15fr 0.85fr;
  }

  .page-about .principle-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px 32px;
  }

  .page-about .version-node summary {
    flex-wrap: nowrap;
  }

  .page-about .version-head {
    flex: 1 1 auto;
  }
}

/* ---------- 桌面主布局 ---------- */
@media (min-width: 900px) {
  .page-about .hero-grid {
    grid-template-columns: minmax(0, 1.45fr) minmax(0, 1fr);
    align-items: end;
    gap: clamp(28px, 4vw, 56px);
  }

  .page-about .coverage-grid {
    grid-template-columns: minmax(0, 1fr) 300px;
    align-items: start;
    gap: clamp(24px, 4vw, 48px);
  }

  .page-about .coverage-media {
    margin: 6px 0 0;
    max-width: none;
  }
}

@media (min-width: 1024px) {
  .page-about .about-layout {
    grid-template-columns: minmax(0, 1fr) 216px;
    align-items: start;
  }

  .page-about .about-toc {
    order: 0;
    position: sticky;
    top: calc(var(--header-height) + 20px);
    border-left: 1px solid var(--line-soft);
    padding-left: 16px;
  }

  .page-about .toc-list {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .toc-list li {
    flex: initial;
  }

  .page-about .toc-list .index-link {
    white-space: normal;
    padding: 8px 10px;
    border-color: transparent;
    background: transparent;
    line-height: 1.5;
  }
}