Hi All, I have created these some custom styles for progress bar of course on dashboard . I have used these with adaptable theme. 
/* Changing the color of progress bar*/
.block .block-cards .progress {
background: #e6e3e3 !important;
height: 15px;
padding: 3px;
}
.block .block-cards .progress:after {
content: '';
display: block;
background: linear-gradient(to right, #67b26b, #4ca2cb) !important;
height: 100%;
border-radius: 2px;
}
.progress-bar {
background: linear-gradient(to right, #67b26b, #4ca2cb);
}
I hope this will help. Enjoy!