Q:

How to check whether my website is responsive or not?

I have been given a task to convert an already hosted website into responsive.  My working knowledge on CSS is below average. 
In that quest, I heard about media queries. I looked for a solution, but what I got was more confusion. Media Queries? I tried responsinator.com and checked my website in that. Actually I don't know how to know whether a website is responsive or not. 
My website fits the mobile screens.  Header and footer automatically adjusts themselves. 
There is a big slider and it just got cropped, but still loads images and works fine. If my website is responsive, how come the slider get cropped?
To make a responsive CSS, Will I have to make any changes to the values in my already existing CSS? Or will I have to just add my styles (without any edits) into the media queries given below.
@media(max-width:480px){
/*PUT YOUR CLASSES STYLES HERE*/
}

A:

your media query defines which part of your css to look in, think of it like an if statement.
When it falls within a media query in your css file, your css has be defined to cater for that screen size, 
Just because your page objects crop when you make the screen smaller does not make your site responsive,
best take your phone or tablet and visit your site, if the user interface is simple, easy and smooth, then you dont have to worry, but if you have a desktop styled site on a phone as wide as your numpad on the keyboard, you have some work to do.

