They have responsive design, to be user friendly. It’s how they are coded. You could design your website to be responsive without any coding, using a website builder like UltimateWB – but you would need access as the admin to the website.
Got a techy/website question? Whether it’s about UltimateWB or another website builder, web hosting, or other aspects of websites, just send in your question in the “Ask David!” form. We will email you when the answer is posted on the UltimateWB “Ask David!” section.