Remove grey box of slider for some images/all images

Is it possible to remove grey box for one particular image?I need to remove for one image only?

You mean the caption background? Yes, you can remove it as you did with `.carousel-caption {
background: none;
}`

For one slide only, use:

.slide-755 .carousel-caption {
    background: none;
}

As a general rule: in Firebug/developer tools, go up the chain of html until you find a class that is sufficiently specific to target just the thing you are interested in—but not too broad to include other things as well—and add it to the front. So the code above will target the caption background, but only for slide 755 (your second slide).

@electric feet thanks a lot man, you made my day.

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