Slider full width but caption contained within inner wrapper

I wanted to contain the caption within the inner wrapper width (1140px in my case) and have it slightly indented on the left, close to the top. In case this helps I’ve managed to do amending the below CSS. If anyone can see any issue please let me know 🙂 Thanks.

.slideshow_container .slideshow_description_box { background: none;
margin-left: auto !important;
margin-right: auto !important;
left: 20px !important;
right: 0 !important;
width: 1140px !important;
top: 20px !important;
}

.slideshow_container .slideshow_description_box div,
.slideshow_container .slideshow_description_box div a,
.slideshow_container .slideshow_description_box p,
.slideshow_container .slideshow_description_box p a,
.slideshow_container .slideshow_description_box h1,
.slideshow_container .slideshow_description_box h1 a,
.slideshow_container .slideshow_description_box h2,
.slideshow_container .slideshow_description_box h2 a,
.slideshow_container .slideshow_description_box h3,
.slideshow_container .slideshow_description_box h3 a,
.slideshow_container .slideshow_description_box h4,
.slideshow_container .slideshow_description_box h4 a,
.slideshow_container .slideshow_description_box h5,
.slideshow_container .slideshow_description_box h5 a,
.slideshow_container .slideshow_description_box h6,
.slideshow_container .slideshow_description_box h6 a {
text-align: left;
color: #fff;
background: #000;
width: 200px !important;
padding: 8px;
}

https://wordpress.org/plugins/slideshow-jquery-image-gallery/