/* Dev Concepts - standalone section, not linked from main project */
:root {
  --dc-bg: #0f1419;
  --dc-surface: #1a2332;
  --dc-border: #2d3a4d;
  --dc-text: #e6edf3;
  --dc-muted: #8b949e;
  --dc-accent: #58a6ff;
  --dc-accent-hover: #79b8ff;
  --dc-card-hover: #252d3d;
}

.dev-concepts {
  min-height: 100vh;
  background: var(--dc-bg);
  color: var(--dc-text);
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  padding: 2rem 1rem 3rem;
}

.dev-concepts .container {
  max-width: 720px;
  margin: 0 auto;
}

.dev-concepts h1 {
  font-size: 1.75rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  letter-spacing: -0.02em;
}

.dev-concepts .subtitle {
  color: var(--dc-muted);
  font-size: 1rem;
  margin-bottom: 2rem;
}

.dev-concepts .concept-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.dev-concepts .concept-list li {
  margin-bottom: 0.5rem;
}

.dev-concepts .concept-link {
  display: block;
  padding: 1rem 1.25rem;
  background: var(--dc-surface);
  border: 1px solid var(--dc-border);
  border-radius: 8px;
  color: var(--dc-accent);
  text-decoration: none;
  font-weight: 500;
  transition: background 0.15s, border-color 0.15s;
}

.dev-concepts .concept-link:hover {
  background: var(--dc-card-hover);
  border-color: var(--dc-accent);
  color: var(--dc-accent-hover);
}

.dev-concepts .concept-link:focus {
  outline: 2px solid var(--dc-accent);
  outline-offset: 2px;
}

/* Content pages */
.dev-concepts .content-body {
  line-height: 1.65;
}

.dev-concepts .content-body h2 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-top: 1.5rem;
  margin-bottom: 0.5rem;
  color: var(--dc-text);
}

.dev-concepts .content-body h2:first-child {
  margin-top: 0;
}

.dev-concepts .content-body p {
  margin-bottom: 1rem;
  color: var(--dc-muted);
}

.dev-concepts .content-body ul {
  margin: 0 0 1rem 1.25rem;
  color: var(--dc-muted);
}

.dev-concepts .content-body li {
  margin-bottom: 0.35rem;
}

.dev-concepts .back-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 2rem;
  padding: 0.6rem 1rem;
  background: var(--dc-surface);
  border: 1px solid var(--dc-border);
  border-radius: 6px;
  color: var(--dc-accent);
  text-decoration: none;
  font-weight: 500;
  transition: background 0.15s, border-color 0.15s;
}

.dev-concepts .back-link:hover {
  background: var(--dc-card-hover);
  border-color: var(--dc-accent);
  color: var(--dc-accent-hover);
}

.dev-concepts .back-link:focus {
  outline: 2px solid var(--dc-accent);
  outline-offset: 2px;
}

.dev-concepts .page-title {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--dc-border);
}

/* Code blocks */
.dev-concepts .content-body pre,
.dev-concepts .content-body code {
  font-family: 'Consolas', 'Monaco', 'Ubuntu Mono', monospace;
  font-size: 0.875rem;
}

.dev-concepts .content-body pre {
  background: var(--dc-surface);
  border: 1px solid var(--dc-border);
  border-radius: 6px;
  padding: 1rem 1.25rem;
  overflow-x: auto;
  margin: 0.75rem 0 1rem;
  color: var(--dc-text);
  line-height: 1.5;
}

.dev-concepts .content-body code {
  background: var(--dc-surface);
  border: 1px solid var(--dc-border);
  padding: 0.15em 0.4em;
  border-radius: 4px;
  color: var(--dc-accent);
}

.dev-concepts .content-body pre code {
  background: none;
  border: none;
  padding: 0;
  color: inherit;
}