Caption Width

Hello, please look at the screenshots. I use one slideshow as a widget. How can I adjust width of title and Caption to be full responsive please?

<a href="http://abload.de/image.php?img=fullscreenbgo3c.jpg"></a>
<a href="http://abload.de/image.php?img=small_screenttrkr.jpg"></a>

https://ww.wp.xz.cn/plugins/slideshow-jquery-image-gallery/