This is an alternate style for K2 Designer. All you will do is add the following lines of code in one of the JavaScript files: 

$(document).ready(function() { $('body').append('<style type="text/css"> ** MINIFIED CSS GOES HERE ** </style>'); });

Step by Step:

1. Add the above code to any JS file that is used in the designer
2. Minify the included CSS code using any css minifier website you find from Google (Optional, but saves space in the JS file).
3. Replace  ** MINIFIED CSS GOES HERE ** from the above code with the minified CSS from Step 2

Thats it! 

This does not make any changes to any of the existing CSS, the original CSS is purely being overwritten by this CSS. Removing the above code will revert your designer back to the original style.