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"HTML5 Boilerplate" is a popular template for creating modern HTML5/CSS3 Websites. This Concrete5 theme is based on it and gives you a convenient starting point to create your own themes. Although you could use it as it is, you should customize it and add your own code.
For more information visit html5boilerplate.com.
Source code is also at github: https://github.com/patrickheck/theme_blank_html5_boilerplate