.nutri-calculator {
    max-width: 500px;
    margin: auto;
    padding: 20px;
    background: linear-gradient(to bottom right, #3f87a6, #ebf8e1);
    border-radius: 15px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
    font-family: Arial, sans-serif;
}

h1 {
    text-align: center;
    color: #fff;
    text-shadow: 1px 1px 2px #333;
}

.input-section label {
    display: block;
    margin-top: 10px;
    font-weight: bold;
    color: #fff;
}

.input-section input, 
.input-section select {
    width: 100%;
    padding: 8px;
    margin-top: 5px;
    border-radius: 8px;
    border: none;
    outline: none;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

button {
    margin-top: 15px;
    width: 100%;
    padding: 10px;
    background: #0077b6;
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 16px;
}

button:hover {
    background: #023e8a;
}

.output-section {
    margin-top: 20px;
    padding: 15px;
    background: #ffffffcc;
    border-radius: 10px;
    box-shadow: inset 0 2px 5px rgba(0,0,0,0.05);
}

.output-section h2 {
    color: #0077b6;
}

@media (max-width: 600px) {
    .nutri-calculator {
        padding: 15px;
    }
}