.gst-calculator-container {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    max-width: 500px;
    margin: 0 auto;
    padding: 20px;
    background-color: #f9f9f9;
    border-radius: 10px;
    box-shadow: 0 0 15px rgba(0, 0, 0, 0.1);
}

.gst-calculator-container h3 {
    color: #2c3e50;
    margin-bottom: 20px;
    text-align: center;
    border-bottom: 1px solid #eee;
    padding-bottom: 10px;
}

.gst-calculator-container h4 {
    color: #2c3e50;
    margin-bottom: 15px;
    text-align: center;
}

.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 600;
    color: #34495e;
}

.form-control {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 16px;
    box-sizing: border-box;
}

.btn-calculate {
    width: 100%;
    padding: 12px;
    background-color: #27ae60;
    color: white;
    border: none;
    border-radius: 4px;
    font-size: 16px;
    cursor: pointer;
    transition: background-color 0.3s;
}

.btn-calculate:hover {
    background-color: #219653;
}

.result-container {
    margin-top: 20px;
    padding: 15px;
    background-color: #e8f5e9;
    border-radius: 5px;
    border-left: 4px solid #27ae60;
}

.result-item {
    display: flex;
    justify-content: space-between;
    margin-bottom: 10px;
    padding-bottom: 10px;
    border-bottom: 1px dashed #ccc;
}

.result-item:last-child {
    margin-bottom: 0;
    padding-bottom: 0;
    border-bottom: none;
}

.result-item.total {
    margin-top: 15px;
    padding-top: 10px;
    border-top: 1px solid #27ae60;
    font-weight: bold;
}

.result-label {
    font-weight: 600;
    color: #34495e;
}

.result-value {
    font-weight: 700;
    color: #2c3e50;
}

/* Responsive adjustments */
@media (max-width: 600px) {
    .gst-calculator-container {
        padding: 15px;
    }
}