Post message speech bubble background

Is this possible here? A speech bubble background on a post message?

I'm using phpbb3 forum.

Hi!

You need only that background URL.

Code:

.postbody .content{
background: url(Background URL) no-repeat;
}

How? The speech bubble's size depends in characters inside it. So usually, it changes size.

Then try this:

Code:

.postbody .content{
background: url(Background URL) no-repeat;
background-size: 100% 100% !important;
}

I still need to find a speech bubble image. I'll try that code.

It is working but the speech bubble doesn't look good and the texts are not inside the speech bubble.

bump