You can make the changes in the below-mentioned files.
File name is “H3.js” and its path is “…\Helical Insight\hi\apache-tomcat-7\webapps\hi-ee\js\vendors”. In this file, the default properties of a chart are defined with which it gets rendered by default like the color pattern, size, legend, tooltip, etc. Any changes made here will affect the default look and feel.
File name is “c3.css” and its path is “…\Helical Insight\hi\apache-tomcat-7\webapps\hi-ee\css”. The default CSS properties of the charts can be specified here.
File name “styles.css” and its path is “…\Helical Insight\hi\apache-tomcat-7\webapps\hi-ee\css”. Any changes like color, font, etc which you make changes here will automatically reflect in the entire application.