/* =====================
   CSS VARIABLES (THEMES)
   ===================== */

   :root {
    --bg: #f4f6f5;
    --card: #ffffff;
    --text: #1f2933;
    --muted: #6b7280;
    --primary: #0f9d58;   /* Naija green */
    --secondary: #e6f4ec;
    --accent: #f59e0b;    /* subtle accent */
    --border: #e5e7eb;
  }
  
  html[data-theme="dark"] {
    --bg: #0f172a;
    --card: #111827;
    --text: #e5e7eb;
    --muted: #9ca3af;
    --primary: #22c55e;
    --secondary: #052e1a;
    --accent: #fbbf24;
    --border: #1f2937;
  }
  
  html[data-theme="light"] {
    --bg: #ffffff;
    --card: #f9fafb;
    --text: #111827;
    --muted: #6b7280;
    --primary: #16a34a;
    --secondary: #ecfdf5;
    --accent: #0ea5e9;
    --border: #e5e7eb;
  }
  
  /* =====================
     RESET & BASE
     ===================== */
  
  * {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
  }
  
  body {
    font-family: system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
  }
  
  /* =====================
     HEADER
     ===================== */
  
  .site-header {
    background: linear-gradient(135deg, var(--primary), #0b7a43);
    color: #ffffff;
    padding: 2rem 1rem;
  }
  
  .header-inner {
    max-width: 900px;
    margin: 0 auto;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
  }
  
  .header-inner h1 {
    font-size: 2rem;
  }
  
  .header-inner p {
    opacity: 0.9;
  }
  
  #themeSelector {
    padding: 0.4rem 0.6rem;
    border-radius: 4px;
    border: none;
  }
  
  /* =====================
     LAYOUT
     ===================== */
  
  .container {
    max-width: 900px;
    margin: 2.5rem auto;
    padding: 0 1rem;
  }
  
  .card {
    background: var(--card);
    border-radius: 10px;
    padding: 2rem;
    border: 1px solid var(--border);
    box-shadow: 0 10px 25px rgba(0,0,0,0.04);
  }
  
  /* =====================
     CALCULATOR
     ===================== */
  
  .calculator h2 {
    margin-bottom: 1.5rem;
  }
  
  .form-group {
    margin-bottom: 1.2rem;
  }
  
  label {
    font-weight: 600;
    display: block;
    margin-bottom: 0.4rem;
  }
  
  input[type="number"],
  input[type="text"],
  select {
    width: 100%;
    padding: 0.6rem;
    border-radius: 6px;
    border: 1px solid var(--border);
    background: transparent;
    color: var(--text);
  }
  
  input:focus,
  select:focus {
    outline: none;
    border-color: var(--primary);
  }
  
  /* =====================
     DEDUCTIONS
     ===================== */
  
  .deduction-row {
    display: grid;
    grid-template-columns: auto 1fr auto auto;
    gap: 0.6rem;
    align-items: center;
    margin-bottom: 0.8rem;
  }
  
  .deduction-rate {
    width: 80px;
  }
  
  /* =====================
     BUTTONS
     ===================== */
  
  .action-buttons {
    display: flex;
    gap: 1rem;
    margin: 1.5rem 0;
    flex-wrap: wrap;
  }
  
  .secondary-btn {
    background: var(--secondary);
    border: 1px solid var(--primary);
    color: var(--primary);
    padding: 0.5rem 0.9rem;
    border-radius: 6px;
    cursor: pointer;
  }
  
  .secondary-btn:hover {
    opacity: 0.9;
  }
  
  /* =====================
     RESULTS
     ===================== */
  
  .results {
    margin-top: 1.5rem;
  }
  
  .results h3 {
    margin-bottom: 1rem;
  }
  
  .results p {
    margin-bottom: 0.4rem;
  }
  
  .results .net {
    font-size: 1.1rem;
    color: var(--primary);
  }
  
  .highlight {
    background: var(--secondary);
  }
  
  /* =====================
     FAQ (COLLAPSIBLE)
     ===================== */
  
  .faq details {
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 0.8rem;
    margin-bottom: 0.8rem;
    background: var(--card);
  }
  
  .faq summary {
    cursor: pointer;
    font-weight: 600;
  }
  
  .faq p {
    margin-top: 0.6rem;
    color: var(--muted);
  }
  
  /* =====================
     ADS & FOOTER
     ===================== */
  
  .ad-slot {
    height: 90px;
    background: #e5e7eb;
    margin: 2rem auto;
    border-radius: 6px;
    max-width: 900px;
  }
  
  .trust-note {
    text-align: center;
    color: var(--muted);
    margin-bottom: 1rem;
  }
  
  footer {
    text-align: center;
    font-size: 0.85rem;
    color: var(--muted);
    padding: 1.5rem 1rem;
  }
  
  /* =====================
     RESPONSIVE
     ===================== */
  
  @media (max-width: 600px) {
    .deduction-row {
      grid-template-columns: auto 1fr auto;
    }
  }