/* ================================
   CONVERTER CSS
   Uses same CSS variables as main site for consistency
================================ */
:root {
  --bg: #f5f5f7;
  --card-bg: #ffffff;
  --border: #e0e0e4;
  --text-main: #111827;
  --text-muted: #6b7280;
  --shadow-soft: 0 12px 30px rgba(15,23,42,0.08);
  --accent: #2563eb;
  --accent-light: #dbeafe;
  --accent-dark: #1d4ed8;
  --success: #059669;
  --success-light: #ecfdf5;
}

body.dark-mode {
  --bg: #0f172a;
  --card-bg: #1e293b;
  --border: #334155;
  --text-main: #f1f5f9;
  --text-muted: #94a3b8;
  --shadow-soft: 0 12px 30px rgba(0,0,0,0.3);
  --accent: #60a5fa;
  --accent-light: #1e3a5f;
  --accent-dark: #3b82f6;
  --success: #34d399;
  --success-light: #064e3b;
}

/* ================================
   BASE
================================ */
* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  line-height: 1.6;
  color: var(--text-main);
  background: var(--bg);
  transition: background-color 0.3s, color 0.3s;
}

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

.container { max-width: 960px; margin: 0 auto; padding: 24px; }

.card {
  background: var(--card-bg);
  border-radius: 16px;
  box-shadow: var(--shadow-soft);
  padding: 24px;
  margin-bottom: 24px;
}

.section {
  margin: 24px 0;
  padding: 24px;
  background: var(--card-bg);
  border-radius: 12px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
}

.section h2 {
  color: var(--accent);
  margin-bottom: 16px;
  font-size: 1.25rem;
}

/* ================================
   BREADCRUMB
================================ */
.breadcrumb {
  padding: 12px 24px;
  background: var(--card-bg);
  border-bottom: 1px solid var(--border);
  font-size: 0.875rem;
  color: var(--text-muted);
}

.breadcrumb a { color: var(--accent); }
.breadcrumb a:hover { text-decoration: underline; }

/* ================================
   HERO HEADER
================================ */
.converter-hero {
  background: linear-gradient(135deg, var(--accent), var(--accent-dark));
  color: white;
  padding: 48px 24px;
  text-align: center;
}

.converter-hero h1 {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.converter-hero p { opacity: 0.9; font-size: 1.1rem; }

.quick-answer {
  font-size: 1.3rem !important;
  font-weight: 600;
  opacity: 1 !important;
  background: rgba(255,255,255,0.15);
  display: inline-block;
  padding: 8px 20px;
  border-radius: 8px;
  margin-top: 12px;
}

/* ================================
   CONVERTER WIDGET
================================ */
.category-select-row {
  margin-bottom: 20px;
}

.category-select-row label {
  display: block;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 6px;
}

.category-select-row select,
.converter-col select {
  width: 100%;
  padding: 10px 12px;
  border: 2px solid var(--border);
  border-radius: 10px;
  font-size: 0.95rem;
  background: var(--card-bg);
  color: var(--text-main);
  cursor: pointer;
  appearance: auto;
}

.converter-row {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 16px;
  align-items: end;
}

.converter-col {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.converter-col label {
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
}

.converter-col input[type="number"] {
  width: 100%;
  padding: 14px 16px;
  border: 2px solid var(--border);
  border-radius: 12px;
  font-size: 1.25rem;
  font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
  background: var(--bg);
  color: var(--text-main);
  transition: border-color 0.2s;
}

.converter-col input[type="number"]:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(37,99,235,0.1);
}

.result-display {
  padding: 14px 16px;
  font-size: 1.25rem;
  font-weight: 700;
  font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
  color: var(--accent);
  background: var(--bg);
  border: 2px solid var(--border);
  border-radius: 12px;
  min-height: 52px;
  word-break: break-all;
}

.swap-btn {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: 2px solid var(--border);
  background: var(--card-bg);
  color: var(--text-main);
  cursor: pointer;
  font-size: 1.3rem;
  transition: all 0.2s;
  display: flex;
  align-items: center;
  justify-content: center;
  align-self: center;
  margin-top: 16px;
  flex-shrink: 0;
}

.swap-btn:hover {
  border-color: var(--accent);
  background: var(--accent-light);
  color: var(--accent);
}

.converter-actions {
  margin-top: 16px;
  display: flex;
  gap: 8px;
}

.btn {
  display: inline-block;
  padding: 10px 20px;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  border: none;
  cursor: pointer;
  font-size: 0.9rem;
  transition: all 0.2s;
}

.btn-sm { padding: 8px 16px; font-size: 0.85rem; }

.btn:hover { opacity: 0.9; }

button.btn {
  background: var(--accent);
  color: white;
}

button.btn:hover {
  background: var(--accent-dark);
}

/* ================================
   FORMULA DISPLAY
================================ */
.formula-display {
  margin-top: 16px;
  padding: 16px;
  background: var(--bg);
  border-radius: 10px;
  text-align: center;
  font-size: 1.2rem;
  min-height: 28px;
}

.formula-box {
  font-size: 1.4rem;
  padding: 20px;
  background: var(--bg);
  border: 2px solid var(--accent);
  border-radius: 12px;
  text-align: center;
  margin: 16px 0;
}

.formula-section { background: var(--success-light); border-left: 4px solid var(--success); }

/* ================================
   BATCH TABLE
================================ */
.batch-section h2 { color: var(--accent); margin-bottom: 16px; }

.batch-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.batch-table th,
.batch-table td {
  padding: 10px 14px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.batch-table th {
  background: var(--bg);
  font-weight: 600;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--text-muted);
}

.batch-table tr:hover td { background: var(--accent-light); }

.batch-value {
  font-family: 'Consolas', 'Monaco', monospace;
  font-weight: 600;
}

.batch-highlight td {
  background: var(--accent-light);
  font-weight: 700;
}

/* ================================
   CATEGORY GRID
================================ */
.categories-section { margin: 32px 0; }
.categories-section h2 { font-size: 1.5rem; margin-bottom: 16px; }

.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 12px;
}

.category-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  background: var(--card-bg);
  border-radius: 16px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  padding: 20px 12px;
  text-decoration: none;
  color: var(--text-main);
  border: 2px solid transparent;
  transition: all 0.2s;
}

.category-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: var(--shadow-soft);
  text-decoration: none;
}

.category-icon { font-size: 2rem; margin-bottom: 8px; }
.category-card h3 { font-size: 0.9rem; margin-bottom: 4px; }
.category-card p { font-size: 0.75rem; color: var(--text-muted); }

/* ================================
   UNIT CARDS (Category page)
================================ */
.units-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 12px;
}

.unit-card {
  padding: 16px;
  background: var(--bg);
  border-radius: 10px;
  border: 1px solid var(--border);
}

.unit-card strong { font-size: 1.1rem; color: var(--accent); margin-right: 8px; }
.unit-name { font-weight: 500; }
.unit-desc { font-size: 0.82rem; color: var(--text-muted); margin-top: 6px; }

.badge-si, .badge-metric { background: #dbeafe; color: #1d4ed8; font-size: 0.7rem; padding: 2px 8px; border-radius: 10px; }
.badge-us { background: #fef3c7; color: #92400e; font-size: 0.7rem; padding: 2px 8px; border-radius: 10px; }
.badge-universal { background: #e0e7ff; color: #3730a3; font-size: 0.7rem; padding: 2px 8px; border-radius: 10px; }

/* ================================
   PAIR LIST
================================ */
.pair-list {
  list-style: none;
  columns: 2;
  column-gap: 24px;
}

.pair-list li {
  padding: 8px 0;
  border-bottom: 1px solid var(--border);
}

/* ================================
   REFERENCE TABLE
================================ */
.table-wrap { overflow-x: auto; }

.ref-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.ref-table th,
.ref-table td {
  padding: 10px 14px;
  text-align: right;
  border: 1px solid var(--border);
  font-family: 'Consolas', 'Monaco', monospace;
}

.ref-table th {
  background: var(--bg);
  font-weight: 600;
  text-align: center;
}

.ref-table td:first-child {
  font-weight: 600;
  text-align: left;
}

.ref-table tr:hover td { background: var(--accent-light); }

/* ================================
   ALL CONVERSIONS SECTION
================================ */
.all-conversions-section {
  margin: 40px 0;
}

.all-conversions-section > h2 {
  font-size: 1.5rem;
  margin-bottom: 8px;
}

.all-conversions-section > p {
  color: var(--text-muted);
  margin-bottom: 20px;
}

.all-conv-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 16px;
}

.all-conv-card {
  background: var(--card-bg);
  border-radius: 14px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  padding: 20px;
  border: 1px solid var(--border);
}

.all-conv-card h3 {
  font-size: 1rem;
  color: var(--accent);
  margin-bottom: 12px;
}

.all-conv-input-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
}

.all-conv-input {
  width: 120px;
  padding: 8px 10px;
  border: 2px solid var(--border);
  border-radius: 8px;
  font-size: 1rem;
  font-family: 'Consolas', 'Monaco', monospace;
  background: var(--bg);
  color: var(--text-main);
}

.all-conv-input:focus {
  outline: none;
  border-color: var(--accent);
}

.all-conv-base-unit {
  font-weight: 700;
  font-size: 0.95rem;
}

.equiv-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.85rem;
}

.equiv-table td {
  padding: 6px 10px;
  border-bottom: 1px solid var(--border);
}

.equiv-table td:first-child {
  font-family: 'Consolas', 'Monaco', monospace;
  font-weight: 600;
  text-align: right;
  width: 100px;
}

.equiv-table td:nth-child(2) {
  font-weight: 600;
  color: var(--accent);
  width: 60px;
}

.equiv-name { color: var(--text-muted); }

.all-conv-link {
  display: inline-block;
  margin-top: 10px;
  font-size: 0.85rem;
  font-weight: 600;
}

/* ================================
   CTA BOX
================================ */
.cta-box {
  background: linear-gradient(135deg, var(--accent), var(--accent-dark));
  color: white;
  padding: 32px;
  border-radius: 14px;
  text-align: center;
  margin: 32px 0;
}

.cta-box h2 { margin-bottom: 8px; }
.cta-box p { opacity: 0.9; }

.cta-btn {
  display: inline-block;
  background: white;
  color: var(--accent);
  padding: 10px 24px;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  margin: 8px 4px 0;
  transition: all 0.2s;
}

.cta-btn:hover { opacity: 0.9; text-decoration: none; }

.cta-btn-outline {
  display: inline-block;
  border: 2px solid rgba(255,255,255,0.5);
  color: white;
  padding: 8px 20px;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  margin: 8px 4px 0;
}

.cta-btn-outline:hover { border-color: white; text-decoration: none; }

/* ================================
   ABOUT
================================ */
.about-section p { margin-bottom: 12px; color: var(--text-muted); }

/* ================================
   RELATED CATEGORIES
================================ */
.related-cats { display: flex; flex-wrap: wrap; gap: 8px; }

.related-cat-link {
  display: inline-block;
  padding: 8px 16px;
  border: 2px solid var(--border);
  border-radius: 8px;
  font-weight: 500;
  font-size: 0.9rem;
  transition: all 0.2s;
}

.related-cat-link:hover {
  border-color: var(--accent);
  background: var(--accent-light);
  text-decoration: none;
}

/* ================================
   FOOTER
================================ */
footer {
  text-align: center;
  padding: 32px 24px;
  background: var(--card-bg);
  border-top: 1px solid var(--border);
  margin-top: 48px;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 16px;
  margin-bottom: 16px;
}

.footer-links a {
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 500;
}

.footer-links a:hover { color: var(--accent); }

footer p { color: var(--text-muted); font-size: 0.85rem; margin-bottom: 4px; }
footer a { color: var(--accent); }

/* ================================
   RESPONSIVE
================================ */
@media (max-width: 640px) {
  .converter-row {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .swap-btn {
    margin: 4px auto;
    transform: rotate(90deg);
  }

  .converter-hero { padding: 32px 16px; }
  .converter-hero h1 { font-size: 1.5rem; }

  .category-grid {
    grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
  }

  .all-conv-grid {
    grid-template-columns: 1fr;
  }

  .pair-list { columns: 1; }

  .container { padding: 16px; }
  .card { padding: 16px; }
}

@media (max-width: 480px) {
  .converter-col input[type="number"],
  .result-display {
    font-size: 1.1rem;
    padding: 12px;
  }

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