#ch-calculatrice {
    max-width: 500px;
    margin: 20px auto;
    background: #f8f9fa;
    padding: 20px;
    border-radius: 12px;
    box-shadow: 0 0 15px rgba(0,0,0,0.1);
    font-family: Arial, sans-serif;
}
#ch-calculatrice h3 {
    text-align: center;
    margin-bottom: 15px;
}
#ch-calculatrice label {
    display: block;
    margin-bottom: 12px;
    position: relative;
}
#ch-calculatrice input,
#ch-calculatrice select {
    width: 100%;
    padding: 8px;
    margin-top: 4px;
    box-sizing: border-box;
    border-radius: 6px;
    border: 1px solid #ccc;
}
.ch-buttons {
    display: flex;
    gap: 10px;
    margin-top: 10px;
}
.ch-buttons button {
    flex: 1;
    padding: 10px;
    background-color: #0073aa;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
}
.ch-buttons button:hover {
    background-color: #005a8c;
}
.ch-tooltip {
    display: block;
    font-size: 0.85em;
    color: #555;
    margin-top: 2px;
}
#ch-resultat {
    margin-top: 15px;
    font-weight: bold;
    text-align: center;
}