.about-shell {
  width: min(100% - 2rem, 52rem);
  padding-bottom: 4rem;
}

.about-header {
  position: relative;
  padding: 1rem 0 2rem;
}

.about-header .brand-mark {
  margin: 1.3rem 0 2rem;
  text-align: center;
}

.about-back-link,
.about-footer a,
.about-section a,
.home-about-link,
.target-source-links a {
  color: var(--accent-primary);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.18em;
}

.about-back-link {
  display: inline-flex;
  min-height: 2.75rem;
  align-items: center;
  font-weight: 700;
  text-decoration: none;
}

.about-local-nav {
  display: flex;
  gap: 0.45rem;
  margin: 0 0 1.4rem;
  padding: 0.75rem;
  overflow-x: auto;
  border: 1px solid var(--border-subtle);
  border-radius: 1rem;
  background: var(--surface-overlay);
  box-shadow: var(--shadow-soft);
  scrollbar-width: thin;
}

.about-local-nav a {
  flex: 0 0 auto;
  padding: 0.45rem 0.75rem;
  border-radius: 999px;
  color: var(--text-secondary);
  font-size: 0.82rem;
  font-weight: 700;
  text-decoration: none;
  white-space: nowrap;
}

.about-local-nav a:focus-visible,
.about-back-link:focus-visible,
.about-section a:focus-visible,
.about-footer a:focus-visible,
.home-about-link:focus-visible,
.target-source-details summary:focus-visible,
.target-source-links a:focus-visible {
  outline: 3px solid var(--focus-ring);
  outline-offset: 3px;
}

.about-section {
  margin: 0 0 1.1rem;
  padding: 1.4rem;
  border: 1px solid var(--border-subtle);
  border-radius: 1.1rem;
  background: var(--surface-card);
  box-shadow: var(--shadow-soft);
}

.about-section h2 {
  margin-bottom: 1rem;
  color: var(--text-primary);
  font-size: clamp(1.35rem, 4.2vw, 1.8rem);
  line-height: 1.45;
}

.about-section h3 {
  margin-bottom: 0.45rem;
  color: var(--text-primary);
  font-size: 1.03rem;
}

.about-section p,
.about-section li,
.about-section dd {
  color: var(--text-secondary);
}

.about-section strong,
.about-section dt {
  color: var(--text-primary);
}

.trust-note {
  margin-top: 1rem;
  padding: 1rem;
  border-left: 3px solid var(--accent-primary);
  border-radius: 0.7rem;
  background: var(--surface-elevated);
}

.trust-note p:last-child {
  margin-bottom: 0;
}

.about-steps {
  display: grid;
  gap: 0.8rem;
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: yohai-step;
}

.about-steps li {
  position: relative;
  padding: 0.9rem 0.9rem 0.9rem 3rem;
  border: 1px solid var(--border-subtle);
  border-radius: 0.85rem;
  background: var(--surface-elevated);
  counter-increment: yohai-step;
}

.about-steps li::before {
  content: counter(yohai-step);
  position: absolute;
  top: 0.82rem;
  left: 0.82rem;
  display: grid;
  width: 1.55rem;
  height: 1.55rem;
  place-items: center;
  border: 1px solid var(--border-strong);
  border-radius: 50%;
  color: var(--accent-primary);
  font-family: var(--font-mincho);
  font-size: 0.78rem;
  font-weight: 800;
}

.about-steps strong,
.about-steps span {
  display: block;
}

.about-steps span {
  margin-top: 0.2rem;
  color: var(--text-muted);
  font-size: 0.88rem;
}

.source-list {
  display: grid;
  gap: 0.9rem;
}

.source-card {
  padding: 1rem;
  border: 1px solid var(--border-subtle);
  border-radius: 0.9rem;
  background: var(--surface-elevated);
}

.source-card p:last-of-type {
  margin-bottom: 0.75rem;
}

.source-label {
  margin-bottom: 0.6rem;
  color: var(--accent-primary) !important;
  font-size: 0.82rem;
  font-weight: 800;
  letter-spacing: 0.04em;
}

.source-checked {
  margin-top: 1rem;
  color: var(--text-muted) !important;
  font-size: 0.82rem;
}

.privacy-list {
  display: grid;
  gap: 0.7rem;
  margin: 0;
}

.privacy-list div {
  display: grid;
  grid-template-columns: minmax(6rem, 0.34fr) minmax(0, 1fr);
  gap: 0.8rem;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--border-subtle);
}

.privacy-list div:last-child {
  border-bottom: 0;
}

.privacy-list dt {
  font-weight: 800;
}

.privacy-list dd {
  margin: 0;
}

.faq-list {
  display: grid;
  gap: 0.65rem;
}

.faq-list details {
  border: 1px solid var(--border-subtle);
  border-radius: 0.85rem;
  background: var(--surface-elevated);
}

.faq-list summary {
  padding: 0.9rem 1rem;
  color: var(--text-primary);
  font-weight: 800;
  cursor: pointer;
}

.faq-list details p {
  margin: 0;
  padding: 0 1rem 1rem;
}

.about-link-list {
  display: grid;
  gap: 0.8rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.about-link-list li {
  display: grid;
  gap: 0.2rem;
  padding: 0.9rem;
  border: 1px solid var(--border-subtle);
  border-radius: 0.85rem;
  background: var(--surface-elevated);
}

.about-link-list span {
  color: var(--text-muted);
  font-size: 0.82rem;
}

.about-footer {
  display: grid;
  gap: 0.5rem;
  padding: 1.4rem 0 0;
  text-align: center;
}

.about-footer p {
  color: var(--text-muted);
  font-size: 0.82rem;
}

.target-source-details {
  margin: 0.9rem 0 1.25rem;
  border: 1px solid var(--border-subtle);
  border-radius: 1rem;
  background: var(--surface-overlay);
  box-shadow: var(--shadow-soft);
}

.target-source-details summary {
  min-height: 3rem;
  padding: 0.8rem 1rem;
  color: var(--text-secondary);
  font-weight: 800;
  cursor: pointer;
}

.target-source-details[open] summary {
  border-bottom: 1px solid var(--border-subtle);
}

.target-source-body {
  padding: 1rem;
}

.target-source-body h3 {
  margin-bottom: 0.55rem;
  color: var(--text-primary);
  font-size: 1rem;
}

.target-source-reason,
.target-source-point-note {
  color: var(--text-secondary);
}

.target-source-reason {
  margin-bottom: 0.9rem;
}

.target-source-point-note {
  margin: 0.85rem 0 0;
  font-size: 0.84rem;
}

.target-source-meta {
  display: grid;
  gap: 0;
  margin: 0;
}

.target-source-meta div {
  display: grid;
  grid-template-columns: minmax(6rem, 0.34fr) minmax(0, 1fr);
  gap: 0.75rem;
  padding: 0.62rem 0;
  border-bottom: 1px solid var(--border-subtle);
}

.target-source-meta dt {
  color: var(--text-muted);
  font-size: 0.8rem;
  font-weight: 800;
}

.target-source-meta dd {
  margin: 0;
  color: var(--text-primary);
  font-size: 0.88rem;
}

.target-source-links {
  display: grid;
  gap: 0.65rem;
  margin-top: 1rem;
}

.target-source-links a {
  min-height: 2.75rem;
  padding: 0.65rem 0.8rem;
  border: 1px solid var(--border-subtle);
  border-radius: 0.75rem;
  background: var(--surface-elevated);
  font-size: 0.86rem;
  font-weight: 800;
  text-decoration: none;
}

.home-trust-footer {
  display: grid;
  gap: 0.55rem;
  margin-top: 1.25rem;
  padding: 1.2rem 1rem 0.2rem;
  border-top: 1px solid var(--border-subtle);
  color: var(--text-muted);
  text-align: center;
}

.home-trust-footer p {
  margin: 0;
  color: var(--text-muted);
  font-size: 0.8rem;
}

.home-trust-footer .home-trust-title {
  color: var(--text-primary);
  font-family: var(--font-mincho);
  font-size: 0.9rem;
  font-weight: 800;
  letter-spacing: 0.08em;
}

.home-about-link {
  display: inline-flex;
  min-height: 2.75rem;
  align-items: center;
  justify-content: center;
  margin-top: 0.25rem;
  font-size: 0.86rem;
  font-weight: 800;
  text-decoration: none;
}

body[data-theme="sumi-kin"] .about-section,
body[data-theme="sumi-kin"] .about-local-nav,
body[data-theme="sumi-kin"] .target-source-details {
  background: rgba(25, 23, 18, 0.94);
}

body[data-theme="sumi-kin"] .trust-note,
body[data-theme="sumi-kin"] .about-steps li,
body[data-theme="sumi-kin"] .source-card,
body[data-theme="sumi-kin"] .faq-list details,
body[data-theme="sumi-kin"] .about-link-list li,
body[data-theme="sumi-kin"] .target-source-links a {
  background: #1d1a15;
}

body[data-theme="sumi-kin"] .about-back-link,
body[data-theme="sumi-kin"] .about-footer a,
body[data-theme="sumi-kin"] .about-section a,
body[data-theme="sumi-kin"] .source-label,
body[data-theme="sumi-kin"] .home-about-link,
body[data-theme="sumi-kin"] .target-source-links a {
  color: var(--accent-primary) !important;
}

body[data-theme="sumi-kin"] .target-source-details summary,
body[data-theme="sumi-kin"] .target-source-reason,
body[data-theme="sumi-kin"] .target-source-point-note {
  color: var(--text-secondary);
}

body[data-theme="sumi-kin"] .target-source-body h3,
body[data-theme="sumi-kin"] .target-source-meta dd,
body[data-theme="sumi-kin"] .home-trust-footer .home-trust-title {
  color: var(--text-primary);
}

@media (max-width: 620px) {
  .about-shell {
    width: min(100% - 1.2rem, 52rem);
  }

  .about-section {
    padding: 1.05rem;
  }

  .privacy-list div,
  .target-source-meta div {
    grid-template-columns: 1fr;
    gap: 0.3rem;
  }
}