:root {
    --md-primary: #1D6C4A;
    --md-on-primary: #FFFFFF;
    --md-surface: #FFFFFF;
    --md-surface-variant: #F1F1EF;
    --md-outline: #C9CCC5;
    --md-on-surface: #1B1C19;
    --md-on-surface-variant: #45483F;
    --md-error: #B3261E;
    --md-success: #1D6C4A;
    --md-warning: #7A5A00;
  }
  * { box-sizing: border-box; }
  body { margin: 0; font-family: 'Roboto', Arial, sans-serif; background: var(--md-surface-variant); color: var(--md-on-surface); }
  .login-shell { min-height: 100vh; display: flex; align-items: center; justify-content: center; padding: 16px; }
  .card { background: var(--md-surface); border: 1px solid var(--md-outline); border-radius: 12px; padding: 24px; }
  .login-card { width: 100%; max-width: 360px; }
  .titulo { font-size: 20px; font-weight: 500; margin: 0 0 4px; }
  .subtitulo { font-size: 14px; color: var(--md-on-surface-variant); margin: 0 0 20px; }
  .campo { margin-bottom: 16px; }
  .campo label { display: block; font-size: 13px; margin-bottom: 4px; color: var(--md-on-surface-variant); }
  input, select {
    width: 100%; height: 44px; padding: 0 12px; border-radius: 8px;
    border: 1px solid var(--md-outline); font-size: 16px;
    background: var(--md-surface); color: var(--md-on-surface);
  }
  input:focus, select:focus { outline: none; border-color: var(--md-primary); border-width: 2px; }
  .error-inline { display: block; font-size: 12px; color: var(--md-error); margin-top: 4px; min-height: 14px; }
  .btn-primario {
    width: 100%; height: 44px; border-radius: 8px; border: none;
    background: var(--md-primary); color: var(--md-on-primary);
    font-size: 14px; font-weight: 500; cursor: pointer;
  }
  .btn-primario:disabled { opacity: 0.6; cursor: default; }
  .alerta { border-radius: 8px; padding: 10px 12px; font-size: 13px; margin-bottom: 16px; background: #FBE9E7; color: var(--md-error); }
  .oculto { display: none; }
  @media (max-width: 600px) { .card { padding: 16px; } }
  .shell { max-width: 720px; margin: 0 auto; padding: 24px 16px; }
  .header-bar { display: flex; justify-content: space-between; align-items: center; margin-bottom: 20px; gap: 12px; flex-wrap: wrap; }
  .cards-grid { display: flex; gap: 12px; flex-wrap: wrap; margin-bottom: 20px; }
  .metric-card { flex: 1; min-width: 160px; background: var(--md-surface-variant); border-radius: 12px; padding: 16px; }
  .metric-label { font-size: 13px; color: var(--md-on-surface-variant); margin: 0 0 4px; }
  .metric-value { font-size: 24px; font-weight: 500; margin: 0; }
  .tabs { display: flex; gap: 8px; margin-bottom: 16px; }
  .tab-btn { flex: 1; height: 40px; border-radius: 8px; border: 1px solid var(--md-outline); background: var(--md-surface); color: var(--md-on-surface); cursor: pointer; font-size: 14px; }
  .tab-btn.activo { background: var(--md-primary); color: var(--md-on-primary); border-color: var(--md-primary); }
  .btn-secundario { height: 44px; border-radius: 8px; border: 1px solid var(--md-outline); background: var(--md-surface); color: var(--md-on-surface); font-size: 14px; cursor: pointer; padding: 0 16px; }
  .modal-overlay { position: fixed; top: 0; left: 0; right: 0; bottom: 0; background: rgba(0,0,0,0.4); display: flex; align-items: center; justify-content: center; padding: 16px; }
  .modal { background: var(--md-surface); border-radius: 12px; padding: 20px; max-width: 380px; width: 100%; }
  .modal-overlay.oculto { display: none; }
  .chip { display: inline-block; font-size: 12px; padding: 4px 10px; border-radius: 8px; }
  .chip-en-uso { background: #FFF3CD; color: var(--md-warning); }
  .chip-reservada { background: #E3EAFD; color: #2A4BA0; }
  .chip-disponible { background: #E3F2E9; color: var(--md-success); }