Most websites are built using the CMS (content management system) WordPress. I prefer to use this platform since it is cost effective and future proof for the client. As of March 2018, around 30% of all websites are using WordPress.
I can also design using Bootstrap framework if WordPress is not wanted. Projects will usually run a little higher since it will take more time to code these sites out.
All websites will be SEO friendly and fully responsive across different device resolutions.
Contact us for more information if you have any questions.