/* ===== Estilos generales ===== */
body {
    box-sizing: border-box;
    background: linear-gradient(135deg, #f9fafb 0%, #e9ecef 100%);
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: #343a40;
    margin: 0;
    padding: 0;
}

/* ===== Encabezado ===== */
.gradient-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}
.gradient-header h1 {
    font-weight: 700;
    letter-spacing: -0.5px;
}

/* ===== Tarjetas de resumen ===== */
.stat-card {
    border-radius: 15px;
    padding: 1.5rem;
    color: white;
    box-shadow: 0 6px 20px rgba(0,0,0,0.15);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.2);
}

.income-card {
    background: linear-gradient(135deg, #28a745 0%, #20c997 100%);
}
.expense-card {
    background: linear-gradient(135deg, #dc3545 0%, #fd7e14 100%);
}
.balance-card {
    background: linear-gradient(135deg, #007bff 0%, #6f42c1 100%);
}
.balance-positive {
    background: linear-gradient(135deg, #28a745 0%, #20c997 100%);
}
.balance-negative {
    background: linear-gradient(135deg, #dc3545 0%, #fd7e14 100%);
}

/* ===== Tarjetas y formularios ===== */
.card-custom {
    border: none;
    border-radius: 15px;
    box-shadow: 0 8px 25px rgba(0,0,0,0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    background: #fff;
}
.card-custom:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 28px rgba(0,0,0,0.15);
}

/* ===== Botones ===== */
.btn-custom {
    border-radius: 10px;
    font-weight: 600;
    transition: all 0.3s ease;
}
.btn-custom:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

/* ===== Historial de transacciones ===== */
.transaction-item {
    border-radius: 10px;
    transition: all 0.3s ease;
    background: #fff;
    box-shadow: 0 3px 8px rgba(0,0,0,0.05);
}
.transaction-item:hover {
    background-color: #f8f9fa;
    transform: translateX(5px);
    box-shadow: 0 6px 15px rgba(0,0,0,0.12);
}

/* ===== Notificaciones ===== */
.notification {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1050;
    border-radius: 10px;
    padding: 12px 20px;
    box-shadow: 0 6px 18px rgba(0,0,0,0.2);
    animation: slideIn 0.3s ease;
}
@keyframes slideIn {
    from { transform: translateX(100%); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}

/* ===== Gráficos ===== */
.chart-container {
    position: relative;
    height: 300px;
    padding: 10px;
}

/* ===== Extras ===== */
.emoji-icon {
    font-size: 2rem;
}
.filter-btn.active {
    box-shadow: 0 0 0 3px rgba(13, 110, 253, 0.25);
    font-weight: 600;
}