Why does my carousel border on the right

I am using a carousel in my website and it is somehow not line-aligned, but instead borders 40px to the right

I've tried using margin: 0, margin-left: 0, but nothing seems to work.

Also every time it scrolls through the following images it gets thrown out of line for some reason.

Any help?

my html code

<div class="container">
<div class="row">
    <div class="carousel slide" id="myCarousel">
        <div class="carousel-inner">
            <div class="item active">
                <ul class="thumbnails">
                    <li class="col-md-4">
                        <div class="fff">
                            <div class="thumbnail">
                                <a href="#"><img src="random img" alt=""></a>
                            </div>
                            <div class="caption">
                                <h4>random caption</h4>
                            </div>
                        </div>
                    </li>
                </ul>
            </div>
        </div>
    </div>
</div>

      

        
        
        
      

    

my css code

img {
max-width: 100%;
}
.thumbnails li > .fff .caption {
background: #fff !important;
padding: 10px
}
ul.thumbnails {
margin-bottom: 0px;
}
.caption h4 {
color: #444;
}
.caption p {
color: #999;
}
li {
list-style-type: none;
}
@media (max-width: 767px) {
.page-header, .control-box {
    text-align: center;
}
}

@media (max-width: 479px) {
.caption {
    word-break: break-all;
}
}