.gradient {
    background: linear-gradient(to right, crimson, red, yellow, green, darkGreen);
    height: 4px;
    width: 100%;
}
.strength {
    width: 100%;    
}
.gradient div {
    width: 100%;
    height: 5px;
    background: linear-gradient(to right, white, white);
    float: right;
}