/* ── About / Manual page ──────────────────────────────────────────────────── */

.about-page {
  overflow-y: auto;
  height: 100%;
}

.about-page__inner {
  max-width: 780px;
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
}

/* Header */
.about-page__header {
  margin-bottom: 2rem;
  padding-bottom: 1.25rem;
  border-bottom: 2px solid var(--color-border);
}

.about-page__title {
  font-size: 2rem;
  font-weight: 800;
  margin: 0 0 .4rem;
  color: var(--color-heading, var(--color-text));
}

.about-page__subtitle {
  margin: 0;
  color: var(--color-text-muted, var(--color-text));
  font-size: .975rem;
}

/* Table of contents */
.about-page__toc {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 1rem 1.25rem;
  margin-bottom: 2.5rem;
}

.about-page__toc strong {
  display: block;
  font-size: .75rem;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--color-text-muted, var(--color-text));
  margin-bottom: .5rem;
}

.about-page__toc-list {
  margin: 0;
  padding-left: 1.25rem;
  columns: 2;
  column-gap: 2rem;
  list-style: decimal;
}

.about-page__toc-list li {
  padding: .15rem 0;
  break-inside: avoid;
}

.about-page__toc-link {
  color: var(--color-accent, var(--color-primary));
  text-decoration: none;
  font-size: .9rem;
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
  font-family: inherit;
  text-align: left;
}

.about-page__toc-link:hover {
  text-decoration: underline;
}

/* Sections */
.about-page__section {
  margin-bottom: 3rem;
  scroll-margin-top: 4rem;
}

.about-page__section-title {
  font-size: 1.35rem;
  font-weight: 700;
  margin: 0 0 1rem;
  padding-bottom: .5rem;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-heading, var(--color-text));
}

.about-page__section-body {
  font-size: .95rem;
  line-height: 1.7;
}

.about-page__section-top {
  display: block;
  margin: 1rem 0 0 auto;
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
  font-family: inherit;
  font-size: .8rem;
  color: var(--color-text-muted, var(--color-text));
}

.about-page__section-top:hover {
  color: var(--color-accent, var(--color-primary));
  text-decoration: underline;
}

.about-page__section-body h3 {
  font-size: 1rem;
  font-weight: 700;
  margin: 1.4rem 0 .4rem;
  color: var(--color-heading, var(--color-text));
}

.about-page__section-body p {
  margin: 0 0 .8rem;
}

.about-page__section-body ul,
.about-page__section-body ol {
  margin: 0 0 .8rem;
  padding-left: 1.4rem;
}

.about-page__section-body li {
  margin-bottom: .25rem;
}

/* Code blocks */
.about-page__code {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: .75rem 1rem;
  font-family: var(--font-mono, monospace);
  font-size: .85rem;
  white-space: pre;
  overflow-x: auto;
  margin: .5rem 0 1rem;
  display: block;
}

/* Tables */
.about-page__table {
  width: 100%;
  border-collapse: collapse;
  font-size: .9rem;
  margin-bottom: 1rem;
}

.about-page__table th,
.about-page__table td {
  text-align: left;
  padding: .5rem .75rem;
  border: 1px solid var(--color-border);
}

.about-page__table th {
  background: var(--color-surface);
  font-weight: 700;
  font-size: .8rem;
  text-transform: uppercase;
  letter-spacing: .05em;
}

.about-page__table tr:nth-child(even) td {
  background: var(--color-surface);
}

/* Tip box */
.about-page__tip {
  background: var(--color-accent-muted, color-mix(in srgb, var(--color-accent, #3b82f6) 10%, transparent));
  border-left: 3px solid var(--color-accent, #3b82f6);
  border-radius: 0 6px 6px 0;
  padding: .75rem 1rem;
  margin: .75rem 0 1rem;
  font-size: .9rem;
}

/* FAQ accordion */
.about-page__faq-item {
  border: 1px solid var(--color-border);
  border-radius: 8px;
  margin-bottom: .5rem;
  overflow: hidden;
}

.about-page__faq-item summary {
  padding: .875rem 1rem;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
}

.about-page__faq-item summary::-webkit-details-marker { display: none; }

.about-page__faq-item summary::after {
  content: '+';
  font-size: 1.2rem;
  color: var(--color-text-muted, var(--color-text));
  flex-shrink: 0;
  margin-left: .5rem;
}

.about-page__faq-item[open] summary::after {
  content: '−';
}

.about-page__faq-item summary:hover {
  background: var(--color-surface);
}

.about-page__faq-item > p,
.about-page__faq-item > ol,
.about-page__faq-item > ul {
  padding: .5rem 1rem 1rem;
  margin: 0;
  font-size: .9rem;
  line-height: 1.65;
  border-top: 1px solid var(--color-border);
}

/* kbd */
.about-page__section-body kbd {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  padding: .1em .4em;
  font-family: var(--font-mono, monospace);
  font-size: .85em;
}

/* Footer */
.about-page__footer {
  text-align: center;
  padding-top: 1rem;
  border-top: 1px solid var(--color-border);
  margin-top: 1rem;
}

.about-page__version {
  margin-top: 0.75rem;
  font-size: 0.75rem;
  color: var(--color-text-muted);
  font-family: var(--font-mono, monospace);
}

/* Mobile */
@media (max-width: 600px) {
  .about-page__inner {
    padding: 1.25rem 1rem 3rem;
  }

  .about-page__toc-list {
    columns: 1;
  }

  .about-page__title {
    font-size: 1.5rem;
  }

  .about-page__table {
    font-size: .8rem;
  }

  .about-page__table th,
  .about-page__table td {
    padding: .35rem .5rem;
  }
}