How to change width of q2a sites?

Question

I am using Google Chrome browser and today I accidently change width of my site temporary (110%). That time I saw symbol of magnifying glass right side of the address bar of Chrome browser. Then I clicked it add selected back to normal and site changed to its normal site. This was happened when I was log in as Admin. Does it create any bad effect for my site? Please tell me what is this option and can we do this permanently for our q2a sites. 

Answer 1

That's a browser's (Chrome in your case) feature.

On every website (and not only on q2a) and with almost every browser the user can zoom in (increase the dimensions of the page/fonts displayed on the browser) and zoom out (decrease it).

This of course can origin weird effects on your website.

That's where responsive design (see q2a responsive themes)  (and similar other approaches) comes in.... 

No fixed widths layout, but layout adaptable to all resolutions.