body {
  margin: 0;
  font-family: Arial;
  background: #f4f4f4;
}

header {
  background: #111;
  color: #fff;
  padding: 10px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

nav a {
  color: #fff;
  text-decoration: none;
  margin-left: 10px;
  padding: 6px 10px;
  border-radius: 4px;
}

nav a.active,
nav a:hover {
  background: #444;
}

main {
  padding: 15px;
}

input, select, button {
  padding: 6px;
  margin: 5px 0;
  display: block;
}

table {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
}

td, th {
  border: 1px solid #ccc;
  padding: 6px;
}

hr {
  margin: 20px 0;
}

.resumen {
  background: #fff;
  padding: 10px;
  margin-bottom: 15px;
}


/* Grid principal */
.gastos-grid {
  display: grid;
  grid-template-columns: 1fr 2fr 1fr;
  gap: 20px;
  margin-bottom: 20px;
}

/* Columnas */
.col {
  background: #fff;
  padding: 12px;
  border-radius: 6px;
}

/* Inputs dentro de columnas */
.col input,
.col select,
.col button {
  width: 100%;
}

/* Funcionalidades */
.funciones button {
  background:  #111;
  margin-top: 10px;
  color:white;
}

/* Responsive */
@media (max-width: 900px) {
  .gastos-grid {
    grid-template-columns: 1fr;
  }
}

.detalle-table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 20px;
}

.detalle-table th,
.detalle-table td {
  border: 1px solid #ccc;
  padding: 8px;
  text-align: left;
}

.detalle-table .total {
  background: #f5f5f5;
}

.detalle-table .ahorro {
  background: #e0ffe0;
}