/* ============================================================
   Link-AI Docs — Shared Styles
   Black & white minimal, GPT-style aesthetic
   ============================================================ */

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg: #ffffff;
  --bg-secondary: #f7f7f8;
  --bg-card: #f7f7f8;
  --border: #e5e5e5;
  --text: #1a1a1a;
  --text-secondary: #666666;
  --text-muted: #999999;
  --accent: #1a1a1a;
  --accent-link: #1a1a1a;
  --code-bg: #f0f0f0;
  --code-border: #e0e0e0;
  --success: #22c55e;
  --warning: #f59e0b;
  --error: #ef4444;
  --radius: 8px;
  --max-w: 720px;
  --font: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'SFMono-Regular', 'Consolas', 'Liberation Mono', 'Menlo', monospace;
}

html { font-size: 16px; scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  min-height: 100vh;
}

/* ── Header ── */
.site-header {
  border-bottom: 1px solid var(--border);
  padding: 0 24px;
  position: sticky;
  top: 0;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(8px);
  z-index: 100;
}
.header-inner {
  max-width: 960px;
  margin: 0 auto;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: -0.01em;
}
.logo-icon {
  width: 28px;
  height: 28px;
  background: var(--accent);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: -0.02em;
}
.header-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}
.header-nav a {
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 14px;
  padding: 6px 10px;
  border-radius: 6px;
  transition: background 0.15s, color 0.15s;
}
.header-nav a:hover { background: var(--bg-secondary); color: var(--text); }
.header-nav a.active { color: var(--text); font-weight: 600; }
.header-cta {
  display: flex;
  align-items: center;
  gap: 8px;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  transition: all 0.15s;
  cursor: pointer;
  border: none;
  font-family: var(--font);
}
.btn-outline {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text);
}
.btn-outline:hover { border-color: var(--text); background: var(--bg-secondary); }
.btn-primary {
  background: var(--accent);
  color: white;
}
.btn-primary:hover { opacity: 0.85; }

/* ── Main Layout ── */
.page-wrapper {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 24px;
}
.content-area {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 48px 0 96px;
}

/* ── Breadcrumb ── */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 32px;
}
.breadcrumb a { color: var(--text-muted); text-decoration: none; }
.breadcrumb a:hover { color: var(--text); }
.breadcrumb-sep { color: var(--border); }
.breadcrumb-current { color: var(--text-secondary); }

/* ── Article ── */
.article-header { margin-bottom: 40px; }
.article-title {
  font-size: clamp(24px, 5vw, 34px);
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}
.article-summary {
  font-size: 16px;
  color: var(--text-secondary);
  line-height: 1.7;
  padding: 16px 20px;
  background: var(--bg-secondary);
  border-radius: var(--radius);
  border-left: 3px solid var(--accent);
  margin-bottom: 32px;
}

h2 {
  font-size: 20px;
  font-weight: 700;
  margin-top: 48px;
  margin-bottom: 16px;
  letter-spacing: -0.01em;
}
h3 {
  font-size: 16px;
  font-weight: 700;
  margin-top: 28px;
  margin-bottom: 12px;
}
p { margin-bottom: 16px; color: var(--text-secondary); }
p:last-child { margin-bottom: 0; }
strong { color: var(--text); font-weight: 600; }

a { color: var(--accent-link); text-decoration: underline; text-underline-offset: 3px; }
a:hover { opacity: 0.75; }

/* ── Direct Answer Box ── */
.answer-box {
  background: #1a1a1a;
  color: #f5f5f5;
  border-radius: var(--radius);
  padding: 24px 28px;
  margin: 24px 0;
}
.answer-box-label {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #888;
  margin-bottom: 10px;
}
.answer-box h3 {
  color: white;
  font-size: 15px;
  margin-top: 0;
  margin-bottom: 10px;
}
.answer-box p, .answer-box li { color: #d4d4d4; }

/* ── Code Blocks ── */
.code-block {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin: 16px 0;
  overflow: hidden;
}
.code-block-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 16px;
  background: var(--border);
  border-bottom: 1px solid var(--code-border);
  font-size: 12px;
  color: var(--text-muted);
}
.code-block pre {
  padding: 18px 20px;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--text);
  tab-size: 2;
}
.code-block pre::-webkit-scrollbar { height: 4px; }
.code-block pre::-webkit-scrollbar-track { background: transparent; }
.code-block pre::-webkit-scrollbar-thumb { background: var(--border); border-radius: 2px; }
.copy-btn {
  padding: 4px 10px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  font-size: 12px;
  cursor: pointer;
  color: var(--text-secondary);
  transition: all 0.15s;
  font-family: var(--font);
}
.copy-btn:hover { border-color: var(--text); color: var(--text); }
.copy-btn.copied { color: var(--success); border-color: var(--success); }

/* ── Config Table ── */
.config-table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0;
  font-size: 14px;
}
.config-table th {
  text-align: left;
  padding: 10px 14px;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  font-size: 12px;
  color: var(--text-muted);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.config-table td {
  padding: 12px 14px;
  border: 1px solid var(--border);
  color: var(--text-secondary);
  vertical-align: top;
}
.config-table code {
  font-family: var(--font-mono);
  font-size: 12.5px;
  background: var(--code-bg);
  padding: 2px 6px;
  border-radius: 4px;
  border: 1px solid var(--code-border);
  color: var(--text);
}
.config-table td:first-child { font-weight: 600; color: var(--text); }

/* ── FAQ ── */
.faq-item {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 12px;
  overflow: hidden;
}
.faq-q {
  width: 100%;
  text-align: left;
  background: var(--bg-secondary);
  border: none;
  padding: 16px 20px;
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  cursor: pointer;
  font-family: var(--font);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  transition: background 0.15s;
}
.faq-q:hover { background: var(--border); }
.faq-q::after {
  content: '+';
  font-size: 18px;
  color: var(--text-muted);
  font-weight: 300;
  flex-shrink: 0;
  transition: transform 0.2s;
}
.faq-item.open .faq-q::after { transform: rotate(45deg); }
.faq-a {
  padding: 0 20px;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, padding 0.3s ease;
}
.faq-item.open .faq-a {
  max-height: 500px;
  padding: 0 20px 16px;
}
.faq-a p, .faq-a li { color: var(--text-secondary); font-size: 14.5px; }
.faq-a ul { padding-left: 20px; margin: 8px 0; }
.faq-a li { margin-bottom: 6px; }

/* ── Error List ── */
.error-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
  margin: 16px 0;
}
.error-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
}
.error-card-title {
  font-weight: 700;
  font-size: 14px;
  margin-bottom: 6px;
  color: var(--text);
}
.error-card-desc {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.5;
}
.error-card code {
  font-family: var(--font-mono);
  font-size: 12px;
  background: var(--code-bg);
  padding: 1px 5px;
  border-radius: 3px;
}

/* ── Checklist ── */
.checklist {
  list-style: none;
  padding: 0;
  margin: 16px 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}
.checklist li {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 14px 20px;
  border-bottom: 1px solid var(--border);
  font-size: 14.5px;
  color: var(--text-secondary);
}
.checklist li:last-child { border-bottom: none; }
.checklist li::before {
  content: '☐';
  font-size: 16px;
  flex-shrink: 0;
  margin-top: 1px;
}
.checklist li code {
  font-family: var(--font-mono);
  font-size: 12.5px;
  background: var(--code-bg);
  padding: 1px 6px;
  border-radius: 4px;
  color: var(--text);
}

/* ── CTA ── */
.cta-section {
  margin-top: 48px;
  padding: 28px;
  background: var(--bg-secondary);
  border-radius: var(--radius);
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}
.cta-text {
  flex: 1;
  min-width: 200px;
  font-size: 14px;
  color: var(--text-secondary);
}
.cta-text strong { font-size: 15px; display: block; margin-bottom: 4px; color: var(--text); }

/* ── Inline Code ── */
:not(.code-block) > code {
  font-family: var(--font-mono);
  font-size: 13px;
  background: var(--code-bg);
  padding: 2px 6px;
  border-radius: 4px;
  border: 1px solid var(--code-border);
  color: var(--text);
}

/* ── Divider ── */
.divider { border: none; border-top: 1px solid var(--border); margin: 40px 0; }

/* ── Tool Card ── */
.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 12px;
  margin: 16px 0;
}
.tool-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
}
.tool-card-icon {
  font-size: 24px;
  margin-bottom: 10px;
}
.tool-card h4 {
  font-size: 14px;
  font-weight: 700;
  margin-bottom: 6px;
  color: var(--text);
}
.tool-card p { font-size: 13px; color: var(--text-secondary); }

/* ── Footer ── */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 24px;
  text-align: center;
  font-size: 13px;
  color: var(--text-muted);
}
.site-footer a { color: var(--text-muted); }

/* ── Responsive ── */
@media (max-width: 640px) {
  .header-nav { display: none; }
  .article-title { font-size: 24px; }
  .error-grid { grid-template-columns: 1fr; }
  .cta-section { flex-direction: column; }
  .code-block pre { font-size: 12px; }
}

/* ── Inline CTA inside article ── */
.inline-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: #f0f0f0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 14px;
  color: var(--text-secondary);
  text-decoration: none;
  margin: 8px 4px;
  transition: all 0.15s;
}
.inline-cta:hover {
  background: var(--bg-secondary);
  border-color: var(--border-hover);
  color: var(--text);
  text-decoration: none;
}
.inline-cta.primary {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
}
.inline-cta.primary:hover {
  opacity: 0.85;
  color: white;
}

/* ── What is / Why section ── */
.context-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 24px;
  margin: 16px 0;
}
.context-box h3 {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text);
  margin-top: 0;
}
.context-box p, .context-box li { font-size: 14.5px; color: var(--text-secondary); }
.context-box ul { padding-left: 20px; margin: 8px 0; }

/* ── Compare table ── */
.compare-table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0;
  font-size: 14px;
}
.compare-table th {
  text-align: left;
  padding: 10px 14px;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  font-size: 12px;
  color: var(--text-muted);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.compare-table td {
  padding: 12px 14px;
  border: 1px solid var(--border);
  color: var(--text-secondary);
  vertical-align: top;
}
.compare-table td:first-child { font-weight: 600; color: var(--text); }
.compare-table .good { color: #166534; background: #f0fdf4; }
.compare-table .warn { color: #92400e; background: #fffbeb; }
.compare-table .bad  { color: #991b1b; background: #fef2f2; }