/* ============================================================
   TAB8.CSS — Convertidor de unidades.
   Layout: grilla 2 columnas de bloques + historial al fondo.
   Sigue las convenciones de tab1.css (variables de base.css).
   ============================================================ */

/* ---------- OVERRIDE MAIN-CONTAINER (igual que tab1) ---------- */
.main-container {
  grid-template-columns: 1fr;
  padding: 0.5rem 2rem;
}

.center-column {
  max-width: 100%;
}


/* ---------- CONTENEDOR GENERAL ---------- */
.convertidor-container {
  display:        flex;
  flex-direction: column;
  gap:            2rem;
  width:          100%;
  max-width:      1100px;
  margin:         0 auto;
}

/* ---------- GRILLA DE BLOQUES (2 columnas) ---------- */
.bloques-grid {
  display:               grid;
  grid-template-columns: 1fr 1fr;
  gap:                   1.25rem;
}

/* ---------- BLOQUE INDIVIDUAL ---------- */
.bloque {
  background:    var(--white);
  border-radius: 16px;
  padding:       1.25rem 1.5rem;
  box-shadow:    0 4px 16px var(--shadow);
  display:       flex;
  flex-direction: column;
  gap:           0.9rem;
  position:      relative;
  overflow:      hidden;
}

/* Barra superior de color (igual que tab1 .panel::before) */
.bloque::before {
  content:    '';
  position:   absolute;
  top:        0;
  left:       0;
  right:      0;
  height:     4px;
  background: linear-gradient(90deg, var(--accent-blue), var(--secondary-blue));
}

/* ---------- ENCABEZADO DEL BLOQUE ---------- */
.bloque-titulo {
  display:     flex;
  align-items: center;
  gap:         0.6rem;
  font-family: 'Montserrat', sans-serif;
  font-size:   0.95rem;
  font-weight: 700;
  color:       var(--primary-blue);
}

.bloque-titulo i {
  color:     var(--accent-blue);
  font-size: 0.95rem;
}

/* ---------- FILAS DE CONVERSIÓN ---------- */
/* Contenedor de las 2 filas (entrada y salida) */
.conversion-rows {
  display:        flex;
  flex-direction: column;
  gap:            0.5rem;
}

/* Cada fila horizontal: select | input | botón */
.conversion-row {
  display:     flex;
  align-items: center;
  gap:         0.6rem;
}

/* Inputs: ahora más anchos gracias al layout de 2 filas */
.input-valor,
.input-resultado {
  width:         140px;
  flex-shrink:   0;
  padding:       0.55rem 0.7rem;
  border:        2px solid var(--light-blue);
  border-radius: 8px;
  font-family:   'Inter', sans-serif;
  font-size:     0.95rem;
  min-width:     0;
  transition:    all 0.3s ease;
  text-align:    right;
}

/* Campo editable: borde azul destacado para que invite a escribir */
.input-valor {
  color:        var(--primary-blue);
  background:   var(--white);
  font-weight:  700;
  border-color: var(--accent-blue);
}

.input-valor:focus {
  outline:      none;
  border-color: var(--secondary-blue);
  box-shadow:   0 0 0 3px rgba(74, 144, 197, 0.2);
}

.input-valor::placeholder { color: #7aaac8; }

/* Campo resultado: mismo aspecto que los selects → visualmente "solo lectura" */
.input-resultado {
  color:       var(--text-dark);
  background:  var(--white);
  font-weight: 400;
  cursor:      default;
}

/* Selects: crecen para ocupar el espacio disponible */
.select-unidad {
  flex:          1;
  padding:       0.55rem 0.5rem;
  border:        2px solid var(--light-blue);
  border-radius: 8px;
  background:    var(--white);
  color:         var(--text-dark);
  font-family:   'Inter', sans-serif;
  font-size:     0.82rem;
  cursor:        pointer;
  transition:    all 0.3s ease;
  min-width:     0;
}

.select-unidad:hover { border-color: var(--accent-blue); }
.select-unidad:focus {
  outline:      none;
  border-color: var(--secondary-blue);
  box-shadow:   0 0 0 3px rgba(74, 144, 197, 0.1);
}

/* ---------- BOTÓN INVERTIR ---------- */
.btn-invertir {
  background:      var(--light-blue);
  border:          none;
  border-radius:   50%;
  width:           34px;
  height:          34px;
  display:         flex;
  align-items:     center;
  justify-content: center;
  cursor:          pointer;
  color:           var(--secondary-blue);
  font-size:       0.85rem;
  transition:      all 0.3s ease;
  flex-shrink:     0;
}

.btn-invertir:hover {
  background: var(--accent-blue);
  color:      var(--white);
  transform:  rotate(180deg);
}

/* ---------- BOTÓN COPIAR ---------- */
.btn-copiar {
  background:      var(--light-blue);
  border:          none;
  border-radius:   8px;
  width:           34px;
  height:          34px;
  display:         flex;
  align-items:     center;
  justify-content: center;
  cursor:          pointer;
  color:           var(--secondary-blue);
  font-size:       0.8rem;
  transition:      all 0.25s ease;
  flex-shrink:     0;
  title:           'Copiar valor';
}

.btn-copiar:hover {
  background: var(--accent-blue);
  color:      var(--white);
}

.btn-copiar.copiado {
  background: #2e7d32;
  color:      var(--white);
}

/* ---------- PANEL HISTORIAL ---------- */
.historial-panel {
  background:    var(--white);
  border-radius: 16px;
  padding:       1.5rem;
  box-shadow:    0 4px 16px var(--shadow);
  position:      relative;
  overflow:      hidden;
}

.historial-panel::before {
  content:    '';
  position:   absolute;
  top:        0; left: 0; right: 0;
  height:     4px;
  background: linear-gradient(90deg, var(--secondary-blue), var(--accent-blue));
}

.historial-header {
  display:         flex;
  align-items:     center;
  justify-content: space-between;
  margin-bottom:   1rem;
}

.historial-titulo {
  font-family: 'Montserrat', sans-serif;
  font-size:   1rem;
  font-weight: 700;
  color:       var(--primary-blue);
  display:     flex;
  align-items: center;
  gap:         0.6rem;
}

.historial-titulo i {
  color:     var(--accent-blue);
  font-size: 1rem;
}

.btn-limpiar {
  background:    none;
  border:        1px solid var(--light-blue);
  border-radius: 6px;
  padding:       0.3rem 0.7rem;
  cursor:        pointer;
  color:         var(--text-light);
  font-family:   'Inter', sans-serif;
  font-size:     0.78rem;
  transition:    all 0.2s ease;
  display:       flex;
  align-items:   center;
  gap:           0.35rem;
}

.btn-limpiar:hover {
  border-color: var(--accent-blue);
  color:        var(--accent-blue);
}

/* Lista de entradas del historial */
.historial-lista {
  display:        flex;
  flex-direction: column;
  gap:            0.5rem;
}

.historial-entrada {
  display:        flex;
  align-items:    center;
  gap:            0.5rem;
  padding:        0.55rem 0.75rem;
  background:     var(--bg);
  border-radius:  8px;
  border-left:    3px solid var(--accent-blue);
  font-size:      0.875rem;
}

.historial-categoria {
  font-size:   0.72rem;
  color:       var(--text-light);
  min-width:   90px;
  font-weight: 500;
}

.historial-expr {
  flex:        1;
  color:       var(--text-dark);
  font-weight: 500;
}

.historial-expr strong {
  color: var(--primary-blue);
}

.historial-unidad-largo {
  font-size:  0.72rem;
  color:      var(--text-light);
  font-style: italic;
}

.historial-vacio {
  color:      var(--text-light);
  font-size:  0.875rem;
  text-align: center;
  padding:    1rem 0;
  font-style: italic;
}

/* ---------- RESPONSIVE ---------- */
@media (max-width: 1100px) {
  /* En tablet vuelve a 1 columna */
  .bloques-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 600px) {
  .input-valor,
  .input-resultado {
    width: 110px;
  }

  .select-unidad {
    font-size: 0.8rem;
  }

}