How can we change this blue color?
Edit this file: /var/www/openmediavault/css/defaults.scss
CSS: defaults.scss
$omv-color-more-lighter: #B9DFF8;
$omv-color-lighter: #85C3EC;
$omv-color-default: #5DACDF;
$omv-color-darker: #3B95CF;
$omv-color-more-darker: #1B7BBA;
Change the value of "$omv-color-default" to what you like
Finally execute commind "make" in path "/var/www/openmediavault/css/"