#ring-size-tool {
    font-family: 'Poppins', sans-serif;
    background-color: #424242;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    overflow-y: auto;
    color: #ECEFF1;
}

#ring-size-tool .container {
    background-color: #ECEFF1;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    max-width: 600px;
    width: 90%;
    text-align: center;
    margin: 20px 0;
}

#ring-size-tool .header {
    font-size: 24px;
    margin-bottom: 10px;
    font-weight: 700;
    color: #424242;
}

#ring-size-tool .instructions {
    font-size: 16px;
    margin-bottom: 20px;
    color: #424242;
}

#ring-size-tool .calibration {
    margin-bottom: 70px;
}

#ring-size-tool .calibration input {
    width: 200px;
    margin-top: 10px;
    -webkit-appearance: none;
    appearance: none;
    height: 8px;
    background: #C1FF72;
    outline: none;
    opacity: 0.7;
    transition: opacity .2s;
    border-radius: 5px;
}

#ring-size-tool .calibration input::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    background: #424242;
    cursor: pointer;
    border-radius: 50%;
}

#ring-size-tool .calibration input::-moz-range-thumb {
    width: 20px;
    height: 20px;
    background: #424242;
    cursor: pointer;
    border-radius: 50%;
}

#ring-size-tool .credit-card-container {
    margin: 25px 0;
}

#ring-size-tool .credit-card {
    width: 85.6mm;
    height: 53.98mm;
    border: 1px solid black;
    margin: 10px auto;
    position: relative;
}

#ring-size-tool .ring-chart {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 10px;
    margin-top: 90px;
}

#ring-size-tool .ring-size-circle {
    border: 1px solid black;
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    position: relative;
    background-color: #424242;
    color: #ECEFF1;
}

#ring-size-tool .btn {
    display: inline-block;
    padding: 10px 20px;
    margin: 20px 0;
    font-size: 16px;
    font-weight: 600;
    text-transform: uppercase;
    color: #424242;
    background-color: #C1FF72;
    border: none;
    border-radius: 25px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

#ring-size-tool .btn:hover {
    background-color: #a7e063;
}

#ring-size-tool .logo {
    margin-bottom: 20px;
}

@media (max-width: 600px) {
    #ring-size-tool .header {
        font-size: 20px;
    }
    #ring-size-tool .instructions {
        font-size: 14px;
    }
}

@media (max-width: 400px) {
    #ring-size-tool .header {
        font-size: 18px;
    }
    #ring-size-tool .instructions {
        font-size: 12px;
    }
}