/* ── Reset & Base ──────────────────────────────────────────────────── */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg: #0f1117;
  --surface: #1a1d27;
  --surface-alt: #1e2231;
  --border: #2e3345;
  --text: #e8eaed;
  --text-muted: #9aa0b0;
  --accent: #6c63ff;
  --accent-hover: #7d75ff;
  --accent-glow: rgba(108, 99, 255, 0.2);
  --error: #ff5252;
  --error-bg: rgba(255, 82, 82, 0.1);
  --success: #4caf50;
  --radius: 8px;
  --radius-lg: 12px;
  --font-mono: "SF Mono", "Fira Code", "Cascadia Code", Consolas, monospace;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, sans-serif;
}

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

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  line-height: 1.6;
  min-height: 100vh;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

/* ── Layout ────────────────────────────────────────────────────────── */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 16px;
}

/* ── Header ────────────────────────────────────────────────────────── */
.site-header {
  padding: 24px 0 16px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 24px;
}

.site-header h1 {
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.site-header h1 .accent {
  color: var(--accent);
}

.site-header .subtitle {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-top: 4px;
}

/* ── Ad Slots ──────────────────────────────────────────────────────── */
.ad-slot {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  min-height: 90px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 20px 0;
  overflow: hidden;
}

.ad-slot--banner {
  min-height: 90px;
}

.ad-slot--sidebar {
  min-height: 250px;
}

/* ── Tool Controls ─────────────────────────────────────────────────── */
.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
  margin-bottom: 16px;
}

.controls-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
}

.sample-btn {
  background: var(--surface);
  color: var(--text-muted);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 6px 14px;
  font-size: 0.8rem;
  font-family: var(--font-mono);
  cursor: pointer;
  transition: all 0.15s ease;
}

.sample-btn:hover {
  color: var(--text);
  border-color: var(--accent);
  background: var(--accent-glow);
}

.badge {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 600;
  font-family: var(--font-mono);
  background: var(--surface);
  color: var(--text-muted);
  border: 1px solid var(--border);
}

.badge-json { background: rgba(255, 183, 77, 0.15); color: #ffb74d; border-color: rgba(255, 183, 77, 0.3); }
.badge-yaml { background: rgba(129, 199, 132, 0.15); color: #81c784; border-color: rgba(129, 199, 132, 0.3); }
.badge-toml { background: rgba(100, 181, 246, 0.15); color: #64b5f6; border-color: rgba(100, 181, 246, 0.3); }
.badge-ini  { background: rgba(206, 147, 216, 0.15); color: #ce93d8; border-color: rgba(206, 147, 216, 0.3); }

.target-group {
  display: flex;
  align-items: center;
  gap: 8px;
}

.target-group label {
  color: var(--text-muted);
  font-size: 0.85rem;
  white-space: nowrap;
}

select {
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 8px 32px 8px 12px;
  font-size: 0.9rem;
  font-family: var(--font-mono);
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath d='M2 4l4 4 4-4' fill='none' stroke='%239aa0b0' stroke-width='1.5'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 10px center;
}

select:focus {
  outline: none;
  border-color: var(--accent);
}

/* ── Buttons ───────────────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 20px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.15s ease;
  font-family: var(--font-sans);
  white-space: nowrap;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.btn-primary:hover {
  background: var(--accent-hover);
  box-shadow: 0 0 16px var(--accent-glow);
}

.btn-secondary {
  background: var(--surface);
  color: var(--text);
}

.btn-secondary:hover {
  border-color: var(--accent);
  background: var(--accent-glow);
}

.btn-secondary:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.btn-secondary:disabled:hover {
  border-color: var(--border);
  background: var(--surface);
}

.btn.success {
  border-color: var(--success);
  color: var(--success);
}

/* ── Editor Panels ─────────────────────────────────────────────────── */
.editor-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 16px;
}

.editor-panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 16px;
  background: var(--surface-alt);
  border-bottom: 1px solid var(--border);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-muted);
}

.panel-header .panel-actions {
  display: flex;
  gap: 6px;
}

.panel-header .btn {
  padding: 4px 12px;
  font-size: 0.78rem;
}

textarea {
  width: 100%;
  min-height: 400px;
  padding: 16px;
  background: transparent;
  color: var(--text);
  border: none;
  resize: vertical;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  line-height: 1.6;
  tab-size: 2;
}

textarea:focus {
  outline: none;
}

textarea::placeholder {
  color: var(--text-muted);
  opacity: 0.5;
}

.output-display {
  width: 100%;
  min-height: 400px;
  padding: 16px;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  line-height: 1.6;
  white-space: pre;
  overflow: auto;
  tab-size: 2;
}

.output-display:empty::before {
  content: "Converted output will appear here...";
  color: var(--text-muted);
  opacity: 0.5;
}

/* ── Syntax Highlighting ───────────────────────────────────────────── */
.hl-key     { color: #64b5f6; }
.hl-string  { color: #81c784; }
.hl-number  { color: #ffb74d; }
.hl-keyword { color: #ce93d8; }
.hl-bracket { color: #9aa0b0; }
.hl-comment { color: #616882; font-style: italic; }
.hl-section { color: #ffb74d; font-weight: 600; }

/* ── Error Box ─────────────────────────────────────────────────────── */
.error-box {
  display: none;
  align-items: flex-start;
  gap: 10px;
  padding: 12px 16px;
  background: var(--error-bg);
  border: 1px solid rgba(255, 82, 82, 0.3);
  border-radius: var(--radius);
  margin-bottom: 16px;
  color: var(--error);
  font-size: 0.9rem;
}

.error-box .error-icon {
  flex-shrink: 0;
  font-size: 1.1rem;
  line-height: 1.4;
}

/* ── Action Bar ────────────────────────────────────────────────────── */
.action-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
}

/* ── SEO Content ───────────────────────────────────────────────────── */
.seo-content {
  margin: 40px 0;
  padding-top: 32px;
  border-top: 1px solid var(--border);
}

.seo-content h2 {
  font-size: 1.35rem;
  margin-bottom: 16px;
  color: var(--text);
}

.seo-content h3 {
  font-size: 1.05rem;
  margin: 24px 0 8px;
  color: var(--text);
}

.seo-content p {
  color: var(--text-muted);
  margin-bottom: 12px;
  max-width: 80ch;
}

.seo-content ul {
  color: var(--text-muted);
  padding-left: 24px;
  margin-bottom: 12px;
}

.seo-content li {
  margin-bottom: 4px;
}

.format-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
  margin: 20px 0;
}

.format-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
}

.format-card h4 {
  color: var(--accent);
  margin-bottom: 8px;
}

.format-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* ── Footer ────────────────────────────────────────────────────────── */
.site-footer {
  padding: 24px 0;
  border-top: 1px solid var(--border);
  margin-top: 40px;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.85rem;
}

/* ── Responsive ────────────────────────────────────────────────────── */
@media (max-width: 768px) {
  .editor-grid {
    grid-template-columns: 1fr;
  }

  textarea,
  .output-display {
    min-height: 280px;
  }

  .site-header h1 {
    font-size: 1.35rem;
  }

  .controls {
    flex-direction: column;
    align-items: stretch;
  }

  .controls-row {
    justify-content: center;
  }

  .target-group {
    width: 100%;
  }

  .target-group select {
    flex: 1;
  }

  .action-bar {
    justify-content: center;
  }

  .format-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 12px;
  }

  textarea,
  .output-display {
    min-height: 220px;
    font-size: 0.78rem;
  }

  .btn {
    padding: 6px 14px;
    font-size: 0.82rem;
  }
}