In modern large-scale websites, front-end web development is constructed by the teamwork of developers. To be a professional website, all web pages should strictly follow predefined theme specifications in order to maintain the common look and feel of the web layout. However, this requires a lot of testing effort to ensure that web pages developed by individual developers are compliant with the web theme. This research proposes a system to enable the automatic identification of web theme templates from existing web pages and to examine the compliance of new web pages based on the identified web theme template. By using our system, violations of web themes can be detected as soon as developers commit changes to the version control repository. In this way, the apparent consistency of websites is not only carefully maintained, but the effort for manual validation can also be drastically reduced.