:root {
    --primary-color: #3498db;
    --secondary-color: #2c3e50;
    --accent-color: #e74c3c;
    --light-color: #ecf0f1;
    --dark-color: #34495e;
    --success-color: #2ecc71;
}

/* Reset y estilos base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--dark-color);
    background-color: #f9f9f9;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

header {
    text-align: center;
    padding: 20px 0;
    background-color: var(--secondary-color);
    color: white;
    border-radius: 8px 8px 0 0;
    margin-bottom: 30px;
}

header h1 {
    font-size: 2rem;
}

main {
    flex: 1;
    padding: 20px;
    background-color: white;
    border-radius: 0 0 8px 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

footer {
    text-align: center;
    padding: 20px;
    margin-top: 30px;
    color: var(--dark-color);
    font-size: 0.9rem;
}

/* Formulario */
.form-consulta {
    max-width: 600px;
    margin: 0 auto;
    padding: 20px;
}

.form-group {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: var(--secondary-color);
}

input[type="number"],
select {
    width: 100%;
    padding: 12px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

input[type="number"]:focus,
select:focus {
    border-color: var(--primary-color);
    outline: none;
}

.btn-consultar {
    background-color: var(--primary-color);
    color: white;
    padding: 12px 20px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
    width: 100%;
    transition: background-color 0.3s;
}

.btn-consultar:hover {
    background-color: #2980b9;
}

/* Resultados */
.resultados {
    padding: 20px;
}

.info-estudiante {
    background-color: var(--light-color);
    padding: 20px;
    border-radius: 8px;
    margin-bottom: 30px;
    border-left: 4px solid var(--primary-color);
}

.info-estudiante h2 {
    color: var(--secondary-color);
    margin-bottom: 15px;
    font-size: 1.5rem;
}

.info-estudiante p {
    margin-bottom: 8px;
}

.tabla-notas {
    margin-top: 30px;
}

.tabla-notas h2 {
    color: var(--secondary-color);
    margin-bottom: 15px;
    font-size: 1.5rem;
}

.table-responsive {
    overflow-x: auto;
}

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

th, td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

th {
    background-color: var(--primary-color);
    color: white;
    font-weight: 600;
}

tr:nth-child(even) {
    background-color: #f8f9fa;
}

tr:hover {
    background-color: #f1f1f1;
}

.no-resultados {
    text-align: center;
    padding: 40px;
    color: var(--accent-color);
    font-size: 1.1rem;
}

.btn-volver {
    display: inline-block;
    padding: 12px 20px;
    background-color: var(--success-color);
    color: white;
    text-decoration: none;
    border-radius: 4px;
    margin-top: 20px;
    transition: background-color 0.3s;
}

.btn-volver:hover {
    background-color: #27ae60;
}

.error {
    text-align: center;
    padding: 40px;
    color: var(--accent-color);
}

/* Media Queries para Responsividad */
@media (max-width: 768px) {
    header h1 {
        font-size: 1.5rem;
    }
    
    .info-estudiante h2,
    .tabla-notas h2 {
        font-size: 1.3rem;
    }
    
    th, td {
        padding: 8px 10px;
        font-size: 0.9rem;
    }
    
    .form-consulta {
        padding: 10px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 10px;
    }
    
    header {
        padding: 15px 0;
    }
    
    header h1 {
        font-size: 1.3rem;
    }
    
    .info-estudiante {
        padding: 15px;
    }
    
    th, td {
        padding: 6px 8px;
        font-size: 0.8rem;
    }
    
    .btn-consultar,
    .btn-volver {
        padding: 10px 15px;
    }
}