.slider {
    position: relative;
    -webkit-appearance: none;
    width: 100%;
    height: 7px;
    border-radius: 5px;  
    background: #6e8fb1;
    outline: none;
    opacity: 0.7;
    -webkit-transition: .2s;
    transition: opacity .2s;
}

.slider-container {
    display: inline-block;
    margin: 5px;
}

.slider-label {
    position: relative;
    margin-top: 5px;
}

#sliders {
    text-align: center;
}

#centered-sliders {
    display: inline-block;
}