.page-about {
  --about-col-wide: 920px;
  --about-col-narrow: 860px;
  color: var(--text-primary);
  background: var(--page-bg);
  font-family: var(--font-body);
  line-height: 1.7;
  overflow-x: clip;
}

.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: 32px 0 40px;
  border-bottom: 3px solid var(--ink);
  background:
    radial-gradient(circle at 88% 20%, var(--accent-a) 0 44px, transparent 45px),
    radial-gradient(circle at 12% 78%, var(--section-bg-primary) 0 26px, transparent 27px),
    var(--page-bg);
}

.page-about .about-hero-inner {
  max-width: var(--about-col-narrow);
  margin-inline: auto;
  padding-inline: 20px;
}

.page-about .about-hero .eyebrow {
  display: inline-block;
  margin-bottom: 14px;
}

.page-about .about-hero-title {
  font-family: var(--font-display);
  font-size: clamp(1.7rem, 5vw, 3rem);
  line-height: 1.12;
  letter-spacing: -0.02em;
  margin: 0 0 16px;
  text-wrap: balance;
}

.page-about .about-hero-lead {
  font-size: clamp(1rem, 2vw, 1.2rem);
  font-weight: 500;
  margin: 0 0 22px;
  max-width: 32em;
}

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

.page-about .about-hero-img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: var(--border-w) solid var(--ink);
  box-shadow: var(--shadow-hard);
  background: var(--card-bg);
  object-fit: cover;
}

.page-about .about-toc {
  background: var(--ink);
  border-bottom: 2px solid var(--ink);
}

.page-about .about-toc-inner {
  display: flex;
  align-items: center;
  gap: 8px;
  max-width: var(--about-col-wide);
  margin-inline: auto;
  padding: 10px 20px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-toc-label {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--accent-a);
  white-space: nowrap;
  margin-right: 6px;
}

.page-about .about-toc-link {
  color: #fff;
  background: #1c1c1c;
  border: 2px solid #3a3a3a;
  border-radius: 999px;
  padding: 6px 12px;
  font-size: 13px;
  font-weight: 700;
  text-decoration: none;
  white-space: nowrap;
  transition: background 0.15s, color 0.15s, transform 0.15s;
}

.page-about .about-toc-link:hover,
.page-about .about-toc-link:focus-visible {
  background: var(--accent-a);
  color: var(--ink);
  border-color: var(--accent-a);
  transform: translateY(-2px);
}

.page-about .about-section {
  padding: 56px 0 64px;
  scroll-margin-top: 20px;
}

.page-about .about-section-inner {
  max-width: var(--about-col-narrow);
  margin-inline: auto;
  padding-inline: 20px;
}

.page-about .about-section .eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--ink);
  background: var(--card-bg);
  border: 2px solid var(--ink);
  padding: 4px 10px;
  margin-bottom: 20px;
  text-transform: uppercase;
}

.page-about .about-section .section-title {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 4vw, 2.4rem);
  line-height: 1.12;
  letter-spacing: -0.01em;
  margin: 0 0 14px;
}

.page-about .about-section:target {
  outline: 4px solid var(--accent-b);
  outline-offset: -4px;
}

.page-about .about-lead-text {
  font-family: var(--font-display);
  font-size: clamp(1.05rem, 2.4vw, 1.6rem);
  line-height: 1.4;
  border-left: 6px solid var(--accent-a);
  padding-left: 18px;
  margin: 26px 0 20px;
}

.page-about .about-body-copy p + p {
  margin-top: 14px;
}

.page-about .about-fact-strip {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  margin-top: 30px;
  padding: 10px;
  background: var(--ink);
  border: 2px solid var(--ink);
  box-shadow: 4px 4px 0 rgba(0, 0, 0, 0.15);
}

.page-about .about-fact {
  background: var(--card-bg);
  padding: 12px 10px;
  text-align: center;
  border: 2px solid transparent;
}

.page-about .about-fact dt {
  font-size: 13px;
  color: var(--status-archived);
  letter-spacing: 0.02em;
}

.page-about .about-fact dd {
  font-family: var(--font-display);
  font-size: 1.5rem;
  line-height: 1.15;
  margin: 2px 0 0;
}

.page-about .about-scope {
  background: var(--section-bg-primary);
  border-top: 3px solid var(--ink);
  border-bottom: 3px solid var(--ink);
}

.page-about .about-scope-summary {
  font-size: 1.05rem;
  margin: 0 0 24px;
}

.page-about .about-chart-wrap {
  display: grid;
  gap: 20px;
  align-items: start;
  margin: 24px 0 34px;
}

.page-about .about-chart {
  background: var(--card-bg);
  border: var(--border-w) solid var(--ink);
  box-shadow: var(--shadow-hard);
  padding: 16px 16px 10px;
}

.page-about .about-chart-head {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-bottom: 2px solid var(--ink);
  padding-bottom: 8px;
  margin-bottom: 16px;
}

.page-about .about-chart-row {
  position: relative;
  display: grid;
  grid-template-columns: 72px 1fr 52px;
  gap: 10px;
  align-items: center;
  margin-bottom: 15px;
}

.page-about .about-chart-name {
  font-size: 14px;
  font-weight: 700;
  white-space: nowrap;
}

.page-about .about-chart-track {
  height: 28px;
  background: var(--card-bg-alt);
  border: 2px solid var(--ink);
  overflow: hidden;
}

.page-about .about-chart-fill {
  display: block;
  height: 100%;
}

.page-about .about-chart-row-classic .about-chart-fill {
  width: 82%;
  background: var(--tag-4);
}

.page-about .about-chart-row-new .about-chart-fill {
  width: 100%;
  background: var(--section-bg-primary);
}

.page-about .about-chart-row-special .about-chart-fill {
  width: 32%;
  background: var(--accent-b);
}

.page-about .about-chart-num {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  text-align: right;
}

.page-about .about-chart-row:hover::after,
.page-about .about-chart-row:focus-within::after {
  content: attr(data-tip);
  position: absolute;
  left: 0;
  top: calc(100% + 6px);
  z-index: 6;
  background: var(--ink);
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.02em;
  padding: 4px 8px;
  border: 2px solid var(--ink);
  box-shadow: 2px 2px 0 rgba(0, 0, 0, 0.2);
  white-space: nowrap;
}

.page-about .about-chart-img {
  width: 100%;
  height: auto;
  border: var(--border-w) solid var(--ink);
  box-shadow: var(--shadow-hard);
  background: var(--card-bg);
  object-fit: cover;
}

.page-about .about-subtitle {
  font-family: var(--font-display);
  font-size: 1.2rem;
  margin: 28px 0 14px;
}

.page-about .about-partition-grid {
  display: grid;
  gap: 18px;
  margin: 14px 0 34px;
}

.page-about .about-partition {
  background: var(--card-bg);
  border: var(--border-w) solid var(--ink);
  box-shadow: var(--shadow-hard);
  padding: 16px 18px 14px;
}

.page-about .about-partition h4 {
  font-family: var(--font-display);
  font-size: 1.2rem;
  margin: 0 0 2px;
}

.page-about .about-partition-count {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 700;
  margin: 4px 0 8px;
}

.page-about .about-partition p:last-child {
  margin-bottom: 0;
  font-size: 14px;
}

.page-about .about-partition-yellow {
  border-top: 10px solid var(--section-bg-primary);
}

.page-about .about-partition-coral {
  border-top: 10px solid var(--section-bg-secondary);
}

.page-about .about-partition-blue {
  border-top: 10px solid var(--accent-a);
}

.page-about .about-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 16px;
}

.page-about .about-updates {
  background: var(--section-bg-secondary);
  border-top: 3px solid var(--ink);
  border-bottom: 3px solid var(--ink);
}

.page-about .about-updates-summary {
  margin: 0 0 24px;
}

.page-about .about-timeline {
  display: grid;
  gap: 16px;
  margin: 26px 0 32px;
  padding-left: 22px;
  border-left: 3px solid var(--ink);
}

.page-about .about-timeline-item {
  position: relative;
  background: rgba(255, 255, 255, 0.72);
  border: var(--border-w) solid var(--ink);
  padding: 14px 16px 12px;
}

.page-about .about-timeline-item::before {
  content: "";
  position: absolute;
  left: -31px;
  top: 18px;
  width: 15px;
  height: 15px;
  background: var(--accent-a);
  border: 3px solid var(--ink);
}

.page-about .about-timeline-item.is-current {
  background: var(--card-bg);
  box-shadow: var(--shadow-hard);
}

.page-about .about-timeline-item.is-current::before {
  background: var(--accent-b);
}

.page-about .about-timeline-top {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
}

.page-about .about-timeline-mark {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
}

.page-about .about-timeline-item h3 {
  font-family: var(--font-display);
  font-size: 1.1rem;
  margin: 8px 0 4px;
}

.page-about .about-timeline-item p {
  margin: 0;
  font-size: 14px;
}

.page-about .about-version-grid {
  display: grid;
  gap: 14px;
}

.page-about .about-version-card {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
  background: var(--card-bg);
  border: var(--border-w) solid var(--ink);
  box-shadow: 4px 4px 0 rgba(0, 0, 0, 0.15);
  padding: 14px 16px;
}

.page-about .about-version-card h3 {
  margin: 0;
  font-size: 1rem;
  font-family: var(--font-display);
}

.page-about .about-version-card p {
  width: 100%;
  margin: 0;
  font-size: 14px;
}

.page-about .about-access {
  background: var(--card-bg-alt);
  border-bottom: 3px solid var(--ink);
}

.page-about .about-device-grid {
  display: grid;
  gap: 20px;
  margin-top: 26px;
}

.page-about .about-device-card {
  background: var(--card-bg);
  border: var(--border-w) solid var(--ink);
  box-shadow: var(--shadow-hard);
  padding: 18px;
}

.page-about .about-device-card h3 {
  font-family: var(--font-display);
  font-size: 1.15rem;
  margin: 0 0 12px;
}

.page-about .about-device-card p {
  margin: 0 0 12px;
  font-size: 14px;
}

.page-about .about-device-img {
  display: block;
  width: 100%;
  height: auto;
  border: 2px solid var(--ink);
  background: var(--card-bg-alt);
  object-fit: cover;
}

.page-about .about-device-list {
  margin: 14px 0 0;
  padding-left: 20px;
  display: grid;
  gap: 8px;
  font-size: 14px;
}

.page-about .about-device-card-mobile {
  background: var(--section-bg-primary);
}

.page-about .about-guide {
  background: var(--ink);
  color: #fff;
}

.page-about .about-guide .about-section-inner {
  max-width: 960px;
}

.page-about .about-guide .eyebrow {
  color: var(--ink);
  background: var(--accent-b);
  border-color: var(--accent-b);
}

.page-about .about-guide .section-title {
  color: #fff;
}

.page-about .about-guide-summary {
  color: rgba(255, 255, 255, 0.85);
}

.page-about .about-guide-steps {
  list-style: none;
  margin: 28px 0 32px;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .about-guide-steps li {
  display: grid;
  grid-template-columns: 54px 1fr;
  gap: 12px;
  align-items: start;
  background: #1c1c1c;
  border: 2px solid #3a3a3a;
  padding: 16px;
}

.page-about .about-step-index {
  font-family: var(--font-display);
  font-size: 2rem;
  line-height: 1;
  color: var(--accent-b);
  border-right: 2px solid #3a3a3a;
  padding-right: 12px;
}

.page-about .about-guide-steps h3 {
  color: #fff;
  font-family: var(--font-display);
  font-size: 1.05rem;
  margin: 2px 0 6px;
}

.page-about .about-guide-steps p {
  color: rgba(255, 255, 255, 0.8);
  font-size: 14px;
  margin: 0;
}

.page-about .about-guide-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-guide-actions .btn-primary {
  background: var(--accent-a);
  border-color: var(--accent-a);
  color: var(--ink);
}

.page-about .about-guide-actions .btn-secondary {
  background: transparent;
  border-color: #fff;
  color: #fff;
}

.page-about .about-guide-actions .btn-dark {
  background: var(--accent-b);
  border-color: var(--accent-b);
  color: var(--ink);
}

@media (min-width: 720px) {
  .page-about .about-fact-strip {
    grid-template-columns: repeat(4, 1fr);
  }

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

  .page-about .about-partition-grid {
    grid-template-columns: repeat(3, 1fr);
  }

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

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

  .page-about .about-guide-steps {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 960px) {
  .page-about .about-hero {
    padding: 44px 0 52px;
  }

  .page-about .about-section {
    padding: 68px 0 76px;
  }

  .page-about .about-toc-link {
    padding: 8px 16px;
    font-size: 14px;
  }

  .page-about .about-partition {
    padding: 20px 22px 18px;
  }
}