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

  :root {
    --blue-950: #0c2340;
    --blue-800: #1e3a6e;
    --blue-600: #1d57b0;
    --blue-400: #3b82e0;
    --blue-100: #dbeafe;
    --blue-50:  #eff6ff;
    --teal-600: #0f766e;
    --teal-100: #ccfbf1;
    --slate-700: #334155;
    --slate-500: #64748b;
    --slate-300: #cbd5e1;
    --slate-100: #f1f5f9;
    --white: #ffffff;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --shadow-sm: 0 1px 3px rgba(12,35,64,.07);
    --shadow-md: 0 4px 18px rgba(12,35,64,.10);
  }

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

  body {
    background: var(--white);
    color: var(--slate-700);
    font-family: 'Georgia', 'Times New Roman', serif;
    line-height: 1.75;
    -webkit-font-smoothing: antialiased;
  }

  .page-wrap {
    max-width: 860px;
    margin: 0 auto;
    padding: 2rem 1.25rem 4rem;
  }

  /* ── Title Area ── */
  .page-title-area {
    margin-bottom: 1.5rem;
    padding-bottom: 1.25rem;
    border-bottom: 2px solid var(--blue-100);
  }

  h1 {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: clamp(1.55rem, 3.5vw, 2.05rem);
    font-weight: 700;
    color: var(--blue-950);
    line-height: 1.25;
    margin-bottom: .55rem;
  }

  .page-desc {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: .975rem;
    color: var(--slate-500);
    line-height: 1.6;
    max-width: 680px;
  }

  /* ── Calculator Card ── */
  .calc-card {
    background: var(--white);
    border: 1.5px solid var(--blue-100);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    overflow: hidden;
    margin-bottom: 2.5rem;
  }

  .calc-header {
    background: linear-gradient(135deg, var(--blue-800) 0%, var(--blue-600) 100%);
    padding: 1rem 1.5rem;
    display: flex;
    align-items: center;
    gap: .75rem;
  }

  .calc-header svg { flex-shrink: 0; }

  .calc-header-text h2 {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--white);
    margin: 0;
  }

  .calc-header-text p {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: .78rem;
    color: rgba(255,255,255,.72);
    margin: 0;
  }

  .calc-body { padding: 1.4rem 1.5rem; }

  .calc-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: .9rem 1.25rem;
  }

  @media (max-width: 560px) { .calc-grid { grid-template-columns: 1fr; } }

  .field-group { display: flex; flex-direction: column; gap: .3rem; }
  .field-group.full { grid-column: 1 / -1; }

  label {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: .78rem;
    font-weight: 700;
    color: var(--blue-950);
    letter-spacing: .025em;
    text-transform: uppercase;
  }

  select, input[type="number"] {
    width: 100%;
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: .9rem;
    color: var(--slate-700);
    background: var(--slate-100);
    border: 1.5px solid var(--slate-300);
    border-radius: var(--radius-sm);
    padding: .5rem .7rem;
    transition: border-color .15s, box-shadow .15s;
    appearance: none;
    -webkit-appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='6'%3E%3Cpath d='M0 0l5 6 5-6z' fill='%2364748b'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right .7rem center;
    padding-right: 2rem;
    cursor: pointer;
  }

  select:focus, input[type="number"]:focus {
    outline: none;
    border-color: var(--blue-400);
    box-shadow: 0 0 0 3px rgba(29,87,176,.12);
    background-color: var(--white);
  }

  input[type="range"] {
    width: 100%;
    height: 6px;
    background: var(--blue-100);
    border: none;
    border-radius: 99px;
    cursor: pointer;
    accent-color: var(--blue-600);
    appearance: none;
    -webkit-appearance: none;
    padding: 0;
    margin-top: .25rem;
  }

  .range-labels {
    display: flex;
    justify-content: space-between;
    font-family: system-ui, sans-serif;
    font-size: .7rem;
    color: var(--slate-500);
    margin-top: .15rem;
  }

  .range-val {
    font-family: system-ui, sans-serif;
    font-size: .82rem;
    font-weight: 700;
    color: var(--blue-600);
  }

  /* ── Actions ── */
  .calc-actions {
    margin-top: 1.1rem;
    display: flex;
    gap: .75rem;
    align-items: center;
    flex-wrap: wrap;
  }

  .btn-calc {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: .9rem;
    font-weight: 700;
    color: var(--white);
    background: linear-gradient(135deg, var(--blue-800), var(--blue-600));
    border: none;
    border-radius: var(--radius-sm);
    padding: .65rem 1.6rem;
    cursor: pointer;
    transition: opacity .15s, transform .1s;
    letter-spacing: .02em;
  }

  .btn-calc:hover { opacity: .9; transform: translateY(-1px); }
  .btn-calc:active { transform: translateY(0); }

  .btn-reset {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: .85rem;
    color: var(--slate-500);
    background: none;
    border: 1.5px solid var(--slate-300);
    border-radius: var(--radius-sm);
    padding: .65rem 1rem;
    cursor: pointer;
    transition: border-color .15s, color .15s;
  }

  .btn-reset:hover { border-color: var(--blue-400); color: var(--blue-600); }

  /* ── Results ── */
  .results-panel {
    display: none;
    margin-top: 1.25rem;
    background: var(--blue-50);
    border: 1.5px solid var(--blue-100);
    border-radius: var(--radius-md);
    padding: 1.15rem 1.3rem;
    animation: fadeUp .25s ease;
  }

  @keyframes fadeUp {
    from { opacity: 0; transform: translateY(8px); }
    to   { opacity: 1; transform: translateY(0); }
  }

  .results-panel.visible { display: block; }

  .result-label {
    font-family: system-ui, sans-serif;
    font-size: .78rem;
    font-weight: 700;
    color: var(--slate-500);
    text-transform: uppercase;
    letter-spacing: .045em;
    margin-bottom: .2rem;
  }

  .result-main {
    display: flex;
    align-items: baseline;
    gap: .4rem;
    margin-bottom: .4rem;
  }

  .result-amount {
    font-family: system-ui, sans-serif;
    font-size: 2.1rem;
    font-weight: 800;
    color: var(--blue-800);
    line-height: 1;
  }

  .result-period {
    font-family: system-ui, sans-serif;
    font-size: .85rem;
    color: var(--slate-500);
  }

  .result-range {
    font-family: system-ui, sans-serif;
    font-size: .82rem;
    color: var(--slate-500);
    margin-bottom: .85rem;
  }

  .result-breakdown {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: .5rem;
    margin-bottom: .8rem;
  }

  @media (max-width: 480px) { .result-breakdown { grid-template-columns: 1fr 1fr; } }

  .breakdown-item {
    background: var(--white);
    border: 1px solid var(--blue-100);
    border-radius: var(--radius-sm);
    padding: .5rem .65rem;
    text-align: center;
  }

  .bi-label {
    display: block;
    font-family: system-ui, sans-serif;
    font-size: .68rem;
    color: var(--slate-500);
    text-transform: uppercase;
    letter-spacing: .03em;
    margin-bottom: .15rem;
  }

  .bi-val {
    font-family: system-ui, sans-serif;
    font-size: .88rem;
    font-weight: 700;
    color: var(--blue-950);
  }

  .result-note {
    font-family: system-ui, sans-serif;
    font-size: .77rem;
    color: var(--slate-500);
    line-height: 1.55;
    border-top: 1px solid var(--blue-100);
    padding-top: .65rem;
  }

  /* ── Summary Box ── */
  .summary-box {
    background: var(--blue-50);
    border-left: 4px solid var(--blue-600);
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
    padding: 1.25rem 1.5rem;
    margin-bottom: 2.5rem;
  }

  .summary-box h2 {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: 1rem;
    font-weight: 700;
    color: var(--blue-950);
    margin-bottom: .8rem;
    display: flex;
    align-items: center;
    gap: .5rem;
  }

  .summary-badge {
    font-size: .67rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .06em;
    color: var(--white);
    background: var(--blue-600);
    padding: .15rem .5rem;
    border-radius: 99px;
  }

  .summary-box ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: .55rem;
  }

  .summary-box ul li {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: .9rem;
    color: var(--slate-700);
    display: flex;
    gap: .6rem;
    line-height: 1.55;
  }

  .summary-box ul li::before {
    content: '▸';
    color: var(--blue-600);
    flex-shrink: 0;
    margin-top: .05rem;
  }

  .summary-box ul li strong {
    color: var(--blue-950);
    font-weight: 700;
    display: inline;
  }

  /* ── Article ── */
  .article-body h2 {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: 1.28rem;
    font-weight: 700;
    color: var(--blue-950);
    margin: 2rem 0 .6rem;
    line-height: 1.3;
  }

  .article-body h3 {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: 1.03rem;
    font-weight: 700;
    color: var(--blue-600);
    margin: 1.5rem 0 .4rem;
  }

  .article-body p {
    font-size: .975rem;
    color: var(--slate-700);
    margin-bottom: 1rem;
    line-height: 1.8;
  }

  .article-body ul, .article-body ol {
    padding-left: 1.4rem;
    margin-bottom: 1rem;
  }

  .article-body li {
    font-size: .975rem;
    color: var(--slate-700);
    margin-bottom: .4rem;
    line-height: 1.75;
  }

  .article-divider {
    border: none;
    border-top: 1.5px solid var(--blue-100);
    margin: 2rem 0;
  }

  .callout {
    background: var(--teal-100);
    border-left: 3px solid var(--teal-600);
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    padding: .9rem 1.1rem;
    margin: 1.25rem 0;
  }

  .callout p {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: .875rem;
    color: #134e4a;
    margin: 0;
    line-height: 1.6;
  }

  .info-box {
    background: var(--blue-50);
    border: 1.5px solid var(--blue-100);
    border-radius: var(--radius-md);
    padding: 1rem 1.25rem;
    margin: 1.25rem 0;
  }

  .info-box p {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: .875rem;
    color: var(--blue-950);
    margin: 0;
    line-height: 1.6;
  }

  /* ── FAQ ── */
  .faq-section { margin-top: 2.5rem; }

  .faq-section > h2 {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: 1.28rem;
    font-weight: 700;
    color: var(--blue-950);
    margin-bottom: 1.1rem;
  }

  .faq-item {
    border: 1.5px solid var(--blue-100);
    border-radius: var(--radius-md);
    margin-bottom: .65rem;
    overflow: hidden;
    transition: box-shadow .15s;
  }

  .faq-item:hover { box-shadow: var(--shadow-sm); }

  .faq-q {
    width: 100%;
    background: none;
    border: none;
    padding: .9rem 1.1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    text-align: left;
    gap: .75rem;
  }

  .faq-q span {
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: .93rem;
    font-weight: 600;
    color: var(--blue-950);
    line-height: 1.45;
  }

  .faq-icon {
    flex-shrink: 0;
    width: 20px;
    height: 20px;
    background: var(--blue-100);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform .2s, background .2s;
    font-size: .75rem;
    color: var(--blue-600);
    font-weight: 700;
    font-family: system-ui, sans-serif;
  }

  .faq-item.open .faq-icon {
    transform: rotate(45deg);
    background: var(--blue-600);
    color: var(--white);
  }

  .faq-a {
    display: none;
    padding: 0 1.1rem 1rem;
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: .88rem;
    color: var(--slate-700);
    line-height: 1.7;
    border-top: 1px solid var(--blue-50);
  }

  .faq-item.open .faq-a { display: block; }

  /* ── Disclaimer ── */
  .disclaimer {
    margin-top: 2.5rem;
    background: var(--slate-100);
    border-radius: var(--radius-md);
    padding: 1rem 1.25rem;
    font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: .78rem;
    color: var(--slate-500);
    line-height: 1.6;
  }