Display title when mouse hover image

Hello,

I am trying to show the title of an article when the mouse hover an image. (Like here : https://wpsites.net/web-design/display-entry-title-on-featured-image/)

Anyone can help me with that ?
Thank you.

There is an excerpt of my style.css :
Theme used is : Clipboard by Visualkicks

/*-------------------------------------------------------------- */
/*
/*	IMAGE HOVER
/*
/*-------------------------------------------------------------- */

.entry_hover {
    opacity: 0;
    position: absolute;
    display: block;
    z-index: 999;
    width: 100%;
    height: 100%;
    left: 0;
    top: 0;
    background: rgba(255,255,255,.5);
    -webkit-transition-duration: 0s;
    -moz-transition-duration: 0s;
    -ms-transition-duration: 0s;
    -o-transition-duration: 0s;
    transition-duration: 0s;

}

.entry_hover > a {
    display: block;
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
    z-index: 99999;
}

.entry_hover .placement {
    position: absolute;
    top: 50%;
    width: 100%;
    margin-top: -18px;
    text-align: center;

}
.format-audio .entry_hover .placement {
    margin-top: -38px;
}
.entry_hover .iconWrap {
    position: relative;
    display: inline-block;
    width: 35px;
    height: 35px;
    line-height: 37px;
    text-align: center;
    color: #fff;
    font-weight: 300;
    font-size: 15px !important;
    letter-spacing: 0px !important;
}
.entry_hover .iconWrap a {
    position: absolute;
    height: 35px;
    width: 35px;
    top: 0;
    left: 0;
    z-index: 99;
    /* background: url(../images/blank.png) repeat; */
}
.entry_hover .iconWrap span {
    z-index: 1;
}
.entry_hover .iconWrap.lightbox a:first-child {
    z-index: 999;
}
.iconWrap.commentNo {
    width: auto;
    padding: 0 8px;
    font-weight: bold;
}
.postLabel {
    position: absolute;
    z-index: 9999;
    top: -10px;
    right: -30px;
    color: #fff;
    text-align: center;
    text-transform: uppercase;
    line-height: 60px;
    font-size: 10px;
    font-weight: bold;
    width: 80px;
    height: 40px;
    transform:rotate(45deg);
    -ms-transform:rotate(45deg); /* IE 9 */
    -moz-transform:rotate(45deg); /* Firefox */
    -webkit-transform:rotate(45deg); /* Safari and Chrome */
    -o-transform:rotate(45deg); /* Opera */
}