/* AI System 6 · Discipline: the first reading face under
   docs/design/SITE-EDITORIAL.md.

   Paper white, ink black, one oxidized accent. One column, a text serif for
   the body, a system sans for the furniture, hairline rules, no shadows and
   no gradients. The page follows the reader's light or dark setting and
   nothing else; the menu bar is the site's own, so every page here is one
   place. */

html.discipline-note {
  --dp-bg: #f8f6f1;
  --dp-ink: #201e1b;
  --dp-muted: #6d675f;
  --dp-rule: rgba(32, 30, 27, 0.14);
  --dp-surface: #fffefb;
  --dp-accent: #8f4636;
  --dp-accent-ink: #7c3d2f;
  --dp-serif: "New York", "Iowan Old Style", Charter, Georgia, "Songti SC", STSong, "Noto Serif CJK SC", serif;
  --dp-sans: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, "Noto Sans", "PingFang SC", "Hiragino Sans GB", "Noto Sans CJK SC", sans-serif;
  --dp-mono: ui-monospace, "SF Mono", Menlo, "Cascadia Mono", monospace;
  --ink: var(--dp-ink);
  --bar-bg: rgba(248, 246, 241, 0.85);
  --bar-border: var(--dp-rule);
  --footer-ink: var(--dp-muted);
  --footer-shadow: none;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  html.discipline-note {
    --dp-bg: #16161a;
    --dp-ink: #e9e6e0;
    --dp-muted: #a09a91;
    --dp-rule: rgba(233, 230, 224, 0.15);
    --dp-surface: #1d1d22;
    --dp-accent: #d29685;
    --dp-accent-ink: #dca291;
    --bar-bg: rgba(22, 22, 26, 0.85);
    color-scheme: dark;
  }
}

html.discipline-note body {
  background: var(--dp-bg);
  color: var(--dp-ink);
  font-family: var(--dp-sans);
  font-size: 17px;
  line-height: 1.75;
}
html.discipline-note body::before { display: none; }
html.discipline-note:lang(zh-CN) body { line-height: 1.9; }

.dp {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 20px 64px;
}

/* Article header: kicker, title, dek, metadata. Not a hero. */
.dp-header {
  padding: 56px 0 28px;
  border-bottom: 1px solid var(--dp-rule);
}
.dp-kicker {
  margin: 0 0 14px;
  font-family: var(--dp-sans);
  font-size: 13px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--dp-accent-ink);
}
.dp-header h1 {
  margin: 0 0 16px;
  font-family: var(--dp-serif);
  font-size: clamp(30px, 6vw, 38px);
  font-weight: 500;
  line-height: 1.2;
  letter-spacing: -0.01em;
}
.dp-dek {
  margin: 0 0 18px;
  font-family: var(--dp-serif);
  font-size: 19px;
  line-height: 1.6;
  color: var(--dp-muted);
  max-width: 40em;
}
.dp-meta {
  margin: 0;
  font-size: 13px;
  line-height: 1.5;
  color: var(--dp-muted);
}

/* One argument per page, one column, a generous rhythm. */
.dp-article {
  padding: 8px 0 8px;
}
.dp-section {
  padding: 28px 0 4px;
}
.dp-section h2 {
  margin: 0 0 12px;
  font-family: var(--dp-serif);
  font-size: 24px;
  font-weight: 500;
  line-height: 1.3;
  letter-spacing: -0.005em;
}
.dp-section p {
  margin: 0 0 16px;
  font-family: var(--dp-serif);
  font-size: 17.5px;
  line-height: 1.75;
  max-width: 40em;
}
html.discipline-note:lang(zh-CN) .dp-section p { max-width: none; }

/* One callout: quiet surface change, hairline edge, no second palette. */
.dp-callout {
  margin: 36px 0 8px;
  padding: 18px 20px;
  background: var(--dp-surface);
  border: 1px solid var(--dp-rule);
  border-radius: 2px;
}
.dp-callout-title {
  margin: 0 0 8px;
  font-family: var(--dp-sans);
  font-size: 14px;
  font-weight: 600;
  color: var(--dp-accent-ink);
}
.dp-callout p {
  margin: 0 0 10px;
  font-family: var(--dp-serif);
  font-size: 16.5px;
  line-height: 1.7;
}
.dp-callout p:last-child { margin-bottom: 0; }

.dp-actions {
  margin: 28px 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}
.dp-button {
  display: inline-block;
  padding: 9px 18px;
  border: 1px solid var(--dp-ink);
  border-radius: 2px;
  color: var(--dp-bg);
  background: var(--dp-ink);
  font-family: var(--dp-sans);
  font-size: 15px;
  text-decoration: none;
}
.dp-button:hover { background: var(--dp-accent-ink); border-color: var(--dp-accent-ink); }
.dp-quiet {
  font-family: var(--dp-sans);
  font-size: 15px;
  color: var(--dp-ink);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* Sources: numbered, reachable without JavaScript. */
.dp-sources {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--dp-rule);
}
.dp-sources h2 {
  margin: 0 0 12px;
  font-family: var(--dp-serif);
  font-size: 22px;
  font-weight: 500;
  line-height: 1.3;
}
.dp-sources > p {
  margin: 0 0 18px;
  font-family: var(--dp-serif);
  font-size: 15.5px;
  line-height: 1.7;
  color: var(--dp-muted);
  max-width: 40em;
}
.dp-sources ol {
  list-style: none;
  margin: 0;
  padding: 0;
}
.dp-sources li {
  display: grid;
  grid-template-columns: 2em minmax(0, 1fr);
  gap: 0 10px;
  padding: 10px 0;
  border-top: 1px dotted var(--dp-rule);
}
.dp-src-n {
  font-family: var(--dp-mono);
  font-size: 13px;
  color: var(--dp-muted);
  padding-top: 3px;
}
.dp-sources li a {
  font-family: var(--dp-sans);
  font-size: 15px;
  color: var(--dp-accent-ink);
  text-decoration: underline;
  text-underline-offset: 3px;
}
.dp-sources li p {
  margin: 4px 0 0;
  font-family: var(--dp-sans);
  font-size: 14px;
  line-height: 1.6;
  color: var(--dp-muted);
}

.dp-footer {
  margin-top: 48px;
  padding-top: 20px;
  border-top: 1px solid var(--dp-rule);
}
.dp-footer p {
  margin: 0 0 8px;
  font-size: 13px;
  line-height: 1.6;
}
.dp-footer a {
  color: var(--dp-accent-ink);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* Links are visibly links; focus is an outline, never a shadow. */
html.discipline-note a:focus-visible {
  outline: 2px solid var(--dp-accent-ink);
  outline-offset: 2px;
  border-radius: 1px;
}

/* Below 480px the header keeps its measure and the sources keep their gap. */
@media (max-width: 480px) {
  .dp { padding-inline: 16px; }
  .dp-header { padding-top: 40px; }
  .dp-dek { font-size: 17.5px; }
  .dp-section p { font-size: 17px; }
}

@media (prefers-reduced-motion: reduce) {
  html.discipline-note * { transition: none !important; }
}