.page-about {
  --about-green: #43A047;
  --about-purple: #7B1FA2;
  --about-dark: #37474F;
  background: var(--color-page);
}

.page-about .breadcrumbs {
  padding-top: 20px;
}

/* ---------- 首屏封面 ---------- */
.page-about .about-hero {
  position: relative;
  padding: 24px 0 44px;
  background:
    linear-gradient(rgba(33, 33, 33, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(33, 33, 33, 0.04) 1px, transparent 1px);
  background-size: 24px 24px;
}

.page-about .about-hero-grid {
  display: grid;
  gap: 28px;
  align-items: center;
}

.page-about .about-kicker {
  display: inline-flex;
  align-items: center;
  font-family: var(--font-heading);
  font-size: 13px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 14px;
  color: var(--color-accent-red-ink);
  background: var(--color-accent-yellow);
  border: var(--border-w) solid var(--color-text);
  padding: 4px 10px;
  box-shadow: 3px 3px 0 rgba(33, 33, 33, 0.16);
}

.page-about .about-hero-title {
  font-family: var(--font-heading);
  font-size: clamp(2.2rem, 7vw, 3.8rem);
  line-height: 1;
  margin: 0 0 12px;
  letter-spacing: 0.01em;
}

.page-about .about-hero-title::after {
  content: "";
  display: block;
  width: 96px;
  height: 8px;
  margin-top: 14px;
  background: repeating-linear-gradient(90deg, var(--color-accent-red) 0 12px, var(--color-accent-yellow) 12px 24px, var(--color-primary) 24px 36px);
  border: 2px solid var(--color-text);
}

.page-about .about-hero-subtitle {
  display: inline-block;
  font-family: var(--font-heading);
  font-size: clamp(0.95rem, 2.4vw, 1.3rem);
  margin: 14px 0 16px;
  color: var(--color-accent-red-ink);
  border-bottom: 3px solid var(--color-accent-red);
  padding-bottom: 4px;
}

.page-about .about-hero-lead {
  font-size: 1rem;
  line-height: 1.7;
  max-width: 54ch;
  margin: 0 0 22px;
}

.page-about .about-hero-stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  max-width: 440px;
}

.page-about .about-hero-stats .stat-cell {
  background: var(--color-card);
  border: var(--border-w) solid var(--color-text);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  box-shadow: 4px 4px 0 rgba(33, 33, 33, 0.14);
}

.page-about .about-hero-stats .stat-num {
  display: block;
  font-family: var(--font-heading);
  font-size: 1.7rem;
  color: var(--color-primary-ink);
}

.page-about .about-hero-stats .stat-label {
  font-size: 12px;
  letter-spacing: 0.03em;
}

.page-about .about-hero-index {
  margin-top: 20px;
  border-top: 2px solid var(--color-text);
  padding-top: 12px;
  max-width: 460px;
}

.page-about .hero-index-label {
  display: inline-block;
  font-family: var(--font-heading);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 8px;
  background: var(--color-accent-red);
  color: #fff;
  padding: 3px 8px;
  border-radius: var(--radius-sm);
}

.page-about .hero-index-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .hero-index-links a {
  font-family: var(--font-heading);
  font-size: 13px;
  color: var(--color-text);
  background: var(--color-card);
  border: 2px solid var(--color-text);
  border-radius: var(--radius-sm);
  padding: 6px 10px;
  text-decoration: none;
  box-shadow: 2px 2px 0 rgba(33, 33, 33, 0.14);
  transition: transform var(--transition), box-shadow var(--transition);
}

.page-about .hero-index-links a:hover,
.page-about .hero-index-links a:focus-visible {
  transform: translate(-1px, -1px);
  box-shadow: 4px 4px 0 rgba(33, 33, 33, 0.2);
  outline: none;
}

.page-about .about-hero-figure {
  margin: 0;
}

.page-about .about-hero-figure img {
  width: 100%;
  max-width: 300px;
  height: auto;
  border: var(--border-w) solid var(--color-text);
  border-radius: var(--radius-lg);
  box-shadow: 8px 8px 0 rgba(33, 33, 33, 0.16);
  transform: rotate(1.2deg);
}

/* ---------- 章节通用 ---------- */
.page-about .section-head {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.page-about .section-title {
  margin: 0;
}

.page-about .section-index {
  font-family: var(--font-index);
  font-weight: 700;
  font-size: 13px;
  color: var(--color-accent-red-ink);
  border: 2px solid var(--color-text);
  border-radius: var(--radius-sm);
  padding: 4px 8px;
  background: var(--color-card);
}

.page-about .about-position,
.page-about .about-scope,
.page-about .about-update,
.page-about .about-versions {
  padding: 44px 0;
  border-block: var(--border-w) solid var(--color-text);
}

/* ---------- 01 本站定位 ---------- */
.page-about .about-position {
  background-color: var(--color-panel-a);
  background-image: radial-gradient(rgba(33, 33, 33, 0.08) 1px, transparent 1px);
  background-size: 18px 18px;
}

.page-about .about-position-grid {
  display: grid;
  gap: 28px;
  align-items: center;
}

.page-about .about-position-lead {
  font-size: 1rem;
  line-height: 1.75;
  max-width: 56ch;
  margin: 0;
}

.page-about .about-position-points {
  list-style: none;
  padding: 0;
  margin: 20px 0 0;
  display: grid;
  gap: 10px;
}

.page-about .about-position-points li {
  border: var(--border-w) solid var(--color-text);
  background: var(--color-card);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  font-size: 14px;
  line-height: 1.55;
  box-shadow: 3px 3px 0 rgba(33, 33, 33, 0.12);
}

.page-about .about-position-points span {
  display: inline-block;
  font-family: var(--font-heading);
  font-weight: 700;
  margin-right: 8px;
  color: var(--color-accent-red-ink);
  border-bottom: 2px solid var(--color-accent-yellow);
}

.page-about .about-catalog-sketch {
  position: relative;
  min-height: 240px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px 16px;
}

.page-about .sketch-ring {
  position: absolute;
  top: -4px;
  left: 28px;
  width: 44px;
  height: 44px;
  border: 4px solid var(--color-text);
  border-radius: 50%;
  background: var(--color-accent-yellow);
  z-index: 2;
}

.page-about .sketch-sheet {
  position: relative;
  width: 100%;
  max-width: 300px;
  background: var(--color-card);
  border: var(--border-w) solid var(--color-text);
  border-radius: var(--radius-md);
  padding: 20px;
  box-shadow: 6px 6px 0 rgba(33, 33, 33, 0.16);
  transform: rotate(1.5deg);
}

.page-about .sketch-line {
  display: block;
  height: 8px;
  background: var(--color-border);
  border-radius: 4px;
  margin: 8px 0;
}

.page-about .sketch-line-xl {
  height: 18px;
  width: 72%;
  background: var(--color-text);
}

.page-about .sketch-line-sm {
  width: 46%;
  margin: 0;
}

.page-about .sketch-divider {
  display: block;
  border-top: 2px dashed var(--color-border);
  margin: 14px 0;
}

.page-about .sketch-row {
  display: flex;
  gap: 8px;
  align-items: center;
  padding: 6px 0;
}

.page-about .sketch-chip {
  width: 52px;
  height: 16px;
  border-radius: var(--radius-sm);
  background: var(--color-panel-a);
  border: 1px solid var(--color-text);
}

.page-about .sketch-chip.is-blue {
  background: var(--color-primary);
}

.page-about .sketch-chip.is-red {
  background: var(--color-accent-red);
}

.page-about .sketch-chip.is-yellow {
  background: var(--color-accent-yellow);
}

.page-about .sketch-index-row {
  display: flex;
  gap: 4px;
  padding: 10px 0 0;
  border-top: 2px solid var(--color-text);
  margin-top: 12px;
}

.page-about .sketch-index-row i {
  font-style: normal;
  font-family: var(--font-index);
  font-size: 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 22px;
  height: 22px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
}

/* ---------- 02 收录范围 ---------- */
.page-about .about-scope {
  background-color: var(--color-panel-b);
}

.page-about .about-scope-lead {
  font-size: 0.95rem;
  line-height: 1.7;
  max-width: 70ch;
  margin: 0 0 6px;
}

.page-about .about-magnets-label {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 14px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin: 26px 0 10px;
  display: inline-block;
  border-bottom: 3px solid var(--color-text);
  padding-bottom: 2px;
}

.page-about .about-magnets {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
}

.page-about .about-magnets .magnet:nth-child(1) {
  grid-column: 1 / -1;
}

.page-about .magnet.is-green {
  background: var(--about-green);
}

.page-about .magnet.is-purple {
  background: var(--about-purple);
}

.page-about .magnet.is-dark {
  background: var(--about-dark);
}

.page-about .magnet.is-green,
.page-about .magnet.is-purple,
.page-about .magnet.is-dark {
  color: #fff;
}

.page-about .about-mini-magnets {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

.page-about .about-mini-magnet {
  display: flex;
  flex-direction: column;
  gap: 2px;
  background: var(--color-card);
  border: var(--border-w) solid var(--color-text);
  border-radius: var(--radius-sm);
  padding: 12px;
  text-decoration: none;
  color: var(--color-text);
  box-shadow: 3px 3px 0 rgba(33, 33, 33, 0.12);
  transition: transform var(--transition), box-shadow var(--transition);
}

.page-about .about-mini-magnet:hover,
.page-about .about-mini-magnet:focus-visible {
  transform: translate(-2px, -2px);
  box-shadow: 5px 5px 0 rgba(33, 33, 33, 0.2);
  outline: none;
}

.page-about .mini-name {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 15px;
}

.page-about .mini-range {
  font-size: 12px;
  color: var(--color-primary-ink);
}

.page-about .about-scope-sum {
  margin: 22px 0 0;
  font-size: 14px;
  font-weight: 600;
  background: var(--color-accent-yellow);
  border: var(--border-w) solid var(--color-text);
  display: inline-block;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  box-shadow: 3px 3px 0 rgba(33, 33, 33, 0.12);
}

/* ---------- 03 更新机制 ---------- */
.page-about .about-update {
  background-color: var(--color-panel-c);
  background-image: linear-gradient(rgba(33, 33, 33, 0.06) 1px, transparent 1px);
  background-size: 100% 32px;
}

.page-about .about-update-grid {
  display: grid;
  gap: 24px;
}

.page-about .about-update-lead {
  font-size: 0.95rem;
  line-height: 1.7;
  max-width: 70ch;
  margin: 0;
}

.page-about .about-update-steps {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
}

.page-about .about-update-steps li {
  position: relative;
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 14px;
  padding-bottom: 26px;
}

.page-about .about-update-steps li::before {
  content: "";
  position: absolute;
  left: 21px;
  top: 44px;
  bottom: 0;
  width: 2px;
  background: var(--color-text);
}

.page-about .about-update-steps li:last-child::before {
  display: none;
}

.page-about .step-num {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: var(--border-w) solid var(--color-text);
  border-radius: 50%;
  background: var(--color-accent-yellow);
  font-family: var(--font-heading);
  font-weight: 700;
  box-shadow: 3px 3px 0 rgba(33, 33, 33, 0.14);
}

.page-about .about-update-steps li:nth-child(2) .step-num {
  background: var(--color-primary);
  color: #fff;
}

.page-about .about-update-steps li:nth-child(3) .step-num {
  background: var(--color-accent-red);
  color: #fff;
}

.page-about .about-update-steps li:nth-child(4) .step-num {
  background: var(--color-status-hot);
  color: #fff;
}

.page-about .step-body h3 {
  margin: 0 0 4px;
  font-family: var(--font-heading);
  font-size: 17px;
}

.page-about .step-body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.6;
}

.page-about .about-update-figure {
  margin: 0;
  align-self: start;
  justify-self: start;
}

.page-about .about-update-figure img {
  width: 100%;
  max-width: 200px;
  height: auto;
  border: var(--border-w) solid var(--color-text);
  border-radius: var(--radius-md);
  box-shadow: 6px 6px 0 rgba(33, 33, 33, 0.16);
  transform: rotate(-1.5deg);
}

/* ---------- 04 版本调优记录 ---------- */
.page-about .about-versions {
  background: var(--color-page);
}

.page-about .about-versions-lead {
  font-size: 0.95rem;
  line-height: 1.7;
  max-width: 70ch;
  margin: 0 0 24px;
}

.page-about .about-version-list {
  position: relative;
  margin: 0 0 28px;
  padding: 0;
}

.page-about .about-version-list::before {
  content: "";
  position: absolute;
  left: 13px;
  top: 6px;
  bottom: 6px;
  width: 3px;
  background: var(--color-border);
  border-radius: 3px;
}

.page-about .about-version-item {
  position: relative;
  padding: 0 0 20px 40px;
}

.page-about .version-dot {
  position: absolute;
  left: 8px;
  top: 8px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--color-card);
  border: 3px solid var(--color-status-old);
}

.page-about .about-version-item.is-current .version-dot {
  border-color: var(--color-status-updated);
  background: var(--color-status-updated);
}

.page-about .version-card {
  background: var(--color-card);
  border: var(--border-w) solid var(--color-text);
  border-radius: var(--radius-md);
  padding: 16px;
  box-shadow: var(--shadow);
  transition: transform var(--transition), box-shadow var(--transition);
}

.page-about .about-version-item:hover .version-card,
.page-about .about-version-item:focus-within .version-card {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-hover);
}

.page-about .version-head {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 8px;
  flex-wrap: wrap;
}

.page-about .version-tune {
  font-family: var(--font-index);
  font-size: 12px;
  color: var(--color-status-hot);
}

.page-about .version-card h3 {
  margin: 0 0 4px;
  font-family: var(--font-heading);
  font-size: 17px;
}

.page-about .version-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.6;
}

.page-about .about-feature-grid {
  margin: 34px 0 0;
  background: var(--color-panel-a);
  border: var(--border-w) solid var(--color-text);
  border-radius: var(--radius-md);
  padding: 18px;
  box-shadow: var(--shadow);
}

.page-about .about-feature-grid h3 {
  margin: 0 0 12px;
  font-family: var(--font-heading);
  font-size: 16px;
}

.page-about .about-feature-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 8px;
}

.page-about .about-feature-list li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: 14px;
  line-height: 1.5;
  border-bottom: 1px dashed var(--color-border);
  padding-bottom: 8px;
}

.page-about .about-feature-list li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .feature-mark {
  flex: 0 0 auto;
  min-width: 58px;
  font-family: var(--font-index);
  font-weight: 700;
  font-size: 12px;
  text-align: center;
  border: 1px solid var(--color-text);
  border-radius: var(--radius-sm);
  padding: 2px 6px;
  background: var(--color-card);
  color: var(--color-accent-red-ink);
}

.page-about .about-version-figure {
  margin: 26px 0 0;
}

.page-about .about-version-figure img {
  width: 100%;
  max-width: 400px;
  height: auto;
  border: var(--border-w) solid var(--color-text);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow);
}

.page-about .about-internal-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
  padding-top: 22px;
  border-top: 2px solid var(--color-text);
}

/* ---------- 桌面端增强 ---------- */
@media (min-width: 640px) {
  .page-about .about-hero-stats {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (min-width: 768px) {
  .page-about .about-magnets {
    grid-template-columns: repeat(4, 1fr);
  }

  .page-about .about-magnets .magnet:nth-child(1),
  .page-about .about-magnets .magnet:nth-child(5),
  .page-about .about-magnets .magnet:nth-child(7),
  .page-about .about-magnets .magnet:nth-child(8) {
    grid-column: span 2;
  }

  .page-about .about-mini-magnets {
    grid-template-columns: repeat(4, 1fr);
  }

  .page-about .about-position,
  .page-about .about-scope,
  .page-about .about-update,
  .page-about .about-versions {
    padding: 56px 0;
  }
}

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

  .page-about .about-position-grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 340px);
  }

  .page-about .about-update-grid {
    grid-template-columns: minmax(0, 1fr) 220px;
  }

  .page-about .about-update-figure {
    justify-self: end;
    align-self: center;
  }
}