body {
    font-family: 'Poppins', sans-serif;
    background-color: #f0f4f8; 
    color: #333;
    margin: 0;
    padding: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

.contenedor {
    max-width: 900px;
    width: 100%;
    background-color: #ffffff;
    padding: 40px;
    border-radius: 20px; 
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1); 
}

h1, h2 {
    font-weight: 600;
    color: #1a202c;
    text-align: center;
    margin-bottom: 20px;
}

h1 {
    font-size: 2.5rem;
    color: #4a5568; 
    background: linear-gradient(90deg, #922262, #e53e3e); 
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

h2 {
    font-size: 1.5rem;
    border-bottom: 2px solid #e2e8f0;
    padding-bottom: 10px;
    margin-top: 30px;
    color: #2d3748;
}

.seccion {
    margin-bottom: 30px;
    padding: 20px;
    border: 1px solid #e2e8f0;
    border-left: 5px solid #922262; 
    border-radius: 12px;
    background-color: #f7fafc; 
}

.formulario-campos, .reportes-controles {
    display: flex;
    flex-wrap: wrap;
    gap: 15px; 
    margin-bottom: 15px;
    align-items: center;
}

.formulario-campos input, 
.formulario-campos select, 
.reportes-controles select {
    flex: 1 1 200px; 
    padding: 12px;
    border: 1px solid #cbd5e0;
    border-radius: 8px;
    font-size: 1rem;
    transition: all 0.3s ease;
    background-color: #fff;
}

.formulario-campos input:focus,
.formulario-campos select:focus,
.reportes-controles select:focus {
    outline: none;
    border-color: #922262; 
    box-shadow: 0 0 0 3px rgba(146, 34, 98, 0.2);
}

.formulario-campos button,
.reportes-controles button {
    flex-grow: 1;
}

button {
    padding: 12px 20px;
    border: none;
    color: white;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    font-size: 1rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.btn-registro-estudiante,
.btn-registro-nota,
.btn-reporte,
.btn-mostrar-lista {
    background: linear-gradient(45deg, #e53e3e, #922262);
}

.btn-registro-estudiante:hover,
.btn-registro-nota:hover,
.btn-reporte:hover,
.btn-mostrar-lista:hover {
    background: linear-gradient(45deg, #c53030, #7a1d52);
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
    border-radius: 8px;
    overflow: hidden; 
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
}

th, td {
    border: 1px solid #e2e8f0;
    padding: 12px;
    text-align: left;
}

th {
    background-color: #922262; 
    color: white;
    font-weight: 600;
}

tr:nth-child(even) {
    background-color: #f7fafc; 
}

.alerta-modal {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 15px 25px;
    background-color: #4CAF50; 
    color: white;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
    z-index: 1000;
    display: none;
    opacity: 0;
    transition: opacity 0.5s ease-in-out, transform 0.5s ease-in-out;
    transform: translateY(-20px);
}

.alerta-modal.error {
    background-color: #e53e3e; 
}

.alerta-visible {
    display: block;
    opacity: 1;
    transform: translateY(0);
}

.resultados-reporte {
    margin-top: 20px;
    padding: 15px;
    background-color: #edf2f7;
    border-radius: 8px;
    border: 1px solid #e2e8f0;
}

.resultados-reporte p {
    margin: 0;
    line-height: 1.5;
}

@media (max-width: 600px) {
    body {
        padding: 10px;
    }
    
    .contenedor {
        padding: 20px;
    }

    .formulario-campos, .reportes-controles {
        flex-direction: column;
        gap: 10px;
    }

    .formulario-campos input, 
    .formulario-campos select, 
    .reportes-controles select,
    .formulario-campos button,
    .reportes-controles button {
        width: 100%;
    }
}