body {
    font-family: Arial, sans-serif;
    background: #f3f6fa;
    margin: 0;
    padding: 0;
    color: #333;
}

header {
    text-align: center;
    padding: 30px 20px;
    background: #4a90e2;
    color: white;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: 15px;
    padding: 20px;
    max-width: 950px;
    margin: auto;
}

.card {
    background: white;
    border-radius: 10px;
    padding: 18px;
    text-align: center;
    cursor: pointer;
    border: 2px solid transparent;
    transition: 0.3s;
    font-weight: bold;
}

.card:hover {
    transform: scale(1.05);
    border-color: #4a90e2;
}

.card.selected {
    background: #4a90e2;
    color: white;
    border-color: #2d6bbf;
}

.actions {
    text-align: center;
    margin: 20px 0;
}

button {
    background: #4a90e2;
    border: none;
    color: white;
    padding: 12px 25px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
}

button:hover {
    background: #2d6bbf;
}

.resultado {
    max-width: 850px;
    background: white;
    margin: 20px auto;
    padding: 20px;
    border-radius: 12px;
    box-shadow: 0 3px 10px rgba(0,0,0,0.1);
}

.hidden {
    display: none;
} 

/* ---------- MOBILE RESPONSIVO ---------- */

@media (max-width: 600px) {

    header {
        padding: 20px 10px;
    }

    h1 {
        font-size: 1.5rem;
    }

    header p {
        font-size: 0.95rem;
    }

    .grid {
        grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
        gap: 12px;
        padding: 15px;
    }

    .card {
        padding: 14px;
        font-size: 0.9rem;
        border-radius: 8px;
    }

    .actions {
        margin: 15px 0;
    }

    button {
        width: 90%;
        padding: 12px;
        font-size: 1rem;
    }

    .resultado {
        width: 92%;
        margin: 15px auto;
        padding: 16px;
        font-size: 0.95rem;
    }

    #lista-valores {
        font-size: 1rem;
    }

    #feedback {
        margin-top: 10px;
        line-height: 1.4rem;
    }
}