#hc-stelyum {
    max-width: 750px;
    margin: 20px auto;
    padding: 35px;
    background: #ffffff;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
    font-family: 'Inter', sans-serif;
    border: 1px solid #e2e8f0;
}

#hc-stelyum .hc-header h3 {
    color: #1e293b;
    font-weight: 800;
}

#hc-stelyum .hc-form-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
    margin-top: 20px;
}

#hc-stelyum .hc-btn {
    background: #1e293b;
    color: white;
    margin-top: 25px;
}

#hc-stelyum .hc-btn:hover {
    background: #334155;
}

#hc-stelyum .hc-result {
    background: #f8fafc;
    border: 2px solid #1e293b;
}

#hc-stelyum .hc-result-value {
    color: #2563eb;
    font-size: 40px;
    text-shadow: 0 2px 4px rgba(37, 99, 235, 0.2);
}

@media (max-width: 600px) {
    #hc-stelyum .hc-form-grid {
        grid-template-columns: 1fr 1fr;
    }
}