#hc-stationary {
    max-width: 650px;
    margin: 20px auto;
    padding: 30px;
    background: #ffffff;
    border-radius: 15px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.1);
    font-family: 'Inter', sans-serif;
    border-top: 5px solid #27ae60;
}

#hc-stationary .hc-header h3 {
    color: #27ae60;
    font-weight: 800;
}

#hc-stationary .hc-btn {
    background: #27ae60;
}

#hc-stationary .hc-btn:hover {
    background: #2ecc71;
    box-shadow: 0 0 15px rgba(39, 174, 96, 0.4);
}

#hc-stationary .hc-result {
    background: #f0fff4;
    border: 2px solid #27ae60;
}

#hc-stationary .hc-result-value {
    color: #27ae60;
    font-size: 32px;
}

@media (max-width: 480px) {
    #hc-stationary .hc-form-row {
        flex-direction: column;
    }
}