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

  :root {
    --bg: #F5F2EE;
    --surface: #FFFFFF;
    --surface2: #EDEBE6;
    --text: #1A1714;
    --text2: #6B6560;
    --text3: #A09A94;
    --accent: #b0182b;
    --accent-light: #fbeaec;
    --accent-dark: #7a1020;
    --border: rgba(26,23,20,0.10);
    --border2: rgba(26,23,20,0.20);
    --radius: 14px;
    --radius-sm: 8px;
  }

  body {
    font-family: 'Montserrat', sans-serif;
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
    padding: 2rem 1rem 4rem;
  }

  .page {
    max-width: 680px;
    margin: 0 auto;
  }

  header {
    margin-bottom: 2.5rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid var(--border);
  }
  .eyebrow {
    font-size: 11px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--text3);
    font-weight: 500;
    margin-bottom: 6px;
  }
  header h1 {
    font-size: 28px;
    font-weight: 600;
    letter-spacing: -0.02em;
    line-height: 1.1;
  }
  header h1 span { color: var(--accent); }
  header p {
    font-size: 14px;
    color: var(--text3);
    margin-top: 6px;
  }

  /* Steps */
  .steps {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
  }

  .step-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    transition: border-color 0.2s;
  }
  .step-card.active { border-color: var(--accent); }
  .step-card.done { border-color: var(--border2); }

  .step-header {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 1rem 1.25rem;
    cursor: default;
  }
  .step-card.done .step-header {
    cursor: pointer;
  }
  .step-card.done .step-header:hover .step-title {
    color: var(--accent);
  }
  .step-card.done .step-header:hover .step-number {
    background: var(--accent);
    border-color: var(--accent);
  }
  .step-number {
    width: 26px;
    height: 26px;
    border-radius: 50%;
    background: var(--surface2);
    border: 1px solid var(--border2);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    font-weight: 600;
    color: var(--text3);
    flex-shrink: 0;
    transition: background 0.2s, color 0.2s;
  }
  .step-card.active .step-number {
    background: var(--accent);
    border-color: var(--accent);
    color: #fff;
  }
  .step-card.done .step-number {
    background: var(--text);
    border-color: var(--text);
    color: #fff;
  }
  .step-title {
    font-size: 14px;
    font-weight: 500;
    color: var(--text2);
  }
  .step-card.active .step-title { color: var(--text); }
  .step-card.done .step-title { color: var(--text2); }

  .step-selection {
    margin-left: auto;
    font-size: 13px;
    font-weight: 500;
    color: var(--accent);
    font-family: 'Montserrat', monospace;
    display: none;
  }
  .step-card.done .step-selection { display: block; }

  .step-body {
    padding: 0 1.25rem 1.25rem;
    display: none;
  }
  .step-card.active .step-body { display: block; }

  /* Format grid */
  .format-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
    gap: 8px;
  }

  .format-btn {
    background: var(--surface2);
    border: 1.5px solid transparent;
    border-radius: var(--radius-sm);
    padding: 12px 8px;
    cursor: pointer;
    text-align: center;
    transition: border-color 0.15s, background 0.15s, transform 0.1s;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 3px;
  }
  .format-btn:hover { border-color: var(--border2); background: #f0ede8; }
  .format-btn:active { transform: scale(0.97); }
  .format-btn.selected {
    border-color: var(--accent);
    background: var(--accent-light);
  }
  .format-btn .f-name {
    font-family: 'Montserrat', monospace;
    font-size: 14px;
    font-weight: 500;
    color: var(--text);
  }
  .format-btn.selected .f-name { color: var(--accent-dark); }
  .format-btn .f-sub {
    font-size: 10px;
    color: var(--text3);
  }
  .format-btn.selected .f-sub { color: var(--accent); }

  /* Meters input */
  .meters-wrap {
    display: flex;
    flex-direction: column;
    gap: 10px;
  }
  .input-row {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
  }
  .input-box {
    position: relative;
    flex: 1;
    min-width: 140px;
  }
  .input-box input {
    width: 100%;
    font-family: 'Montserrat', monospace;
    font-size: 28px;
    font-weight: 500;
    color: var(--text);
    background: var(--surface2);
    border: 1.5px solid var(--border2);
    border-radius: var(--radius-sm);
    padding: 10px 52px 10px 14px;
    outline: none;
    transition: border-color 0.2s;
    -moz-appearance: textfield;
  }
  .input-box input::-webkit-inner-spin-button,
  .input-box input::-webkit-outer-spin-button { -webkit-appearance: none; }
  .input-box input:focus { border-color: var(--accent); background: #fff0f2; }
  .input-unit {
    position: absolute;
    right: 14px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 13px;
    color: var(--text3);
    pointer-events: none;
  }
  .btn {
    background: var(--accent);
    color: #fff;
    border: none;
    border-radius: var(--radius-sm);
    font-family: 'Montserrat', sans-serif;
    font-size: 15px;
    font-weight: 500;
    padding: 12px 24px;
    cursor: pointer;
    transition: background 0.15s, transform 0.1s;
    white-space: nowrap;
  }
  .btn:hover { background: var(--accent-dark); }
  .btn:active { transform: scale(0.97); }
  .btn:disabled { background: var(--text3); cursor: not-allowed; transform: none; }
  .input-note {
    font-size: 12px;
    color: var(--text3);
    display: flex;
    align-items: center;
    gap: 5px;
  }
  .input-note::before {
    content: '';
    display: inline-block;
    width: 5px; height: 5px;
    border-radius: 50%;
    background: var(--accent);
    flex-shrink: 0;
  }

  /* Results card */
  .result-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    opacity: 0;
    transform: translateY(12px);
    transition: opacity 0.35s ease, transform 0.35s ease;
    pointer-events: none;
  }
  .result-card.visible {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
  }

  .result-top {
    background: var(--accent);
    padding: 1.1rem 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 8px;
  }
  .result-top .rt-label {
    font-size: 11px;
    letter-spacing: 0.10em;
    text-transform: uppercase;
    color: rgba(255,255,255,0.7);
    font-weight: 500;
  }
  .result-top .rt-fmt {
    font-size: 20px;
    font-weight: 600;
    color: #fff;
    font-family: 'Montserrat', monospace;
    letter-spacing: -0.01em;
  }
  .result-top .rt-meta {
    font-size: 13px;
    color: rgba(255,255,255,0.75);
  }

  .result-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0;
  }
  .rstat {
    padding: 1.25rem 1.25rem;
    display: flex;
    flex-direction: column;
    gap: 4px;
    border-right: 1px solid var(--border);
  }
  .rstat:last-child { border-right: none; }
  .rstat-label {
    font-size: 10px;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--text3);
    font-weight: 500;
  }
  .rstat-val {
    font-size: 30px;
    font-weight: 600;
    font-family: 'Montserrat', monospace;
    color: var(--text);
    letter-spacing: -0.02em;
    line-height: 1.1;
  }
  .rstat-val .u {
    font-size: 14px;
    font-weight: 400;
    color: var(--text3);
    font-family: 'Montserrat', sans-serif;
  }
  .rstat-sub {
    font-size: 12px;
    color: var(--text3);
    margin-top: 2px;
  }

  .result-footer {
    padding: 0.85rem 1.25rem;
    border-top: 1px solid var(--border);
    font-size: 12px;
    color: var(--text3);
    display: flex;
    align-items: center;
    gap: 6px;
  }
  .result-footer::before {
    content: '';
    display: inline-block;
    width: 5px; height: 5px;
    border-radius: 50%;
    background: var(--text3);
    flex-shrink: 0;
  }

  /* Área calculada (paso 2) */
  .metros-resultado {
    display: flex;
    gap: 10px;
  }
  .metros-resultado-label {
    flex: 1;
    min-width: 140px;
    font-size: 11px;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--text3);
    font-weight: 500;
  }
  .metros-total-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: var(--surface2);
    border: 1.5px solid var(--border2);
    border-radius: var(--radius-sm);
    padding: 10px 14px;
    margin-top: 2px;
  }
  .metros-total-label {
    font-size: 13px;
    color: var(--text3);
    font-weight: 500;
  }
  .metros-total-val {
    font-family: 'Montserrat', monospace;
    font-size: 22px;
    font-weight: 600;
    color: var(--accent-dark);
    letter-spacing: -0.02em;
  }
  .metros-total-val.empty { color: var(--text3); font-size: 16px; font-weight: 400; }

  .reset-btn {
    display: none;
    background: none;
    border: 1px solid var(--border2);
    border-radius: var(--radius-sm);
    font-family: 'Montserrat', sans-serif;
    font-size: 13px;
    color: var(--text2);
    padding: 8px 16px;
    cursor: pointer;
    margin-top: 0.75rem;
    transition: background 0.15s;
    width: 100%;
  }
  .reset-btn:hover { background: var(--surface2); }
  .reset-btn.visible { display: block; }

  footer {
    margin-top: 3rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border);
    font-size: 12px;
    color: var(--text3);
    text-align: center;
  }

  @media (max-width: 500px) {
    header h1 { font-size: 22px; }
    .result-stats { grid-template-columns: 1fr 1fr; }
    .rstat:nth-child(2) { border-right: none; }
    .rstat:nth-child(3) { border-top: 1px solid var(--border); grid-column: span 2; }
  }

.multiply-symbol {
  font-size: 20px;
  color: var(--text3);
  font-weight: 500;
  flex-shrink: 0;
}

.metros-resultado-label-offset {
  padding-left: 8px;
}

.calc-row {
  margin-top: 4px;
}

.step-body-result {
  padding-top: 0;
}