[Résolu] Mettre une image en cover dans une classe (prob media queries

@media only screen and (min-width: 576px) and (max-width: 768px)
{
.lddc .bg-img-1 {
	{
		background-image: url('../images/960w/PBal.jpg');
	}

.lddc .bg-img-2
	{
		background-image: url('../images/960w/PBal1.jpg');
	}

.lddc .bg-img-3
	{
		background-image: url('../images/960w/PBal1.jpg');
}
.lddc .bg-img-4
	{
		background-image: url('../images/960w/PBal1.jpg');
	}
.lddc .bg-img-5 {
		background-image: url('../images/960w/PBal1.jpg');
}
}

.lddc .sl-slider-wrapper {
	width: 100%;
	height: 650px;
	overflow: hidden;
	position: relative;
	left: 0px;
	margin: 0px;
	top: 0px;
	bottom: 0px;
	right: 0px;
}

.lddc .sl-slider h2,
.lddc .sl-slider blockquote {
	padding: 300px 30px 10px;
	width: 80%;
	max-width: 960px;
	color: #fff;
	margin: 0 auto;
	position: relative;
	z-index: 100;
	text-align: center;
}

.lddc .sl-slider h2,
.lddc .sl-slider {
	font-family: 'Holtwood One SC';
	}


.lddc .sl-slider h3 {
	width: 100%;
	color: #fff;
	margin: 0 auto;
	position: relative;
	z-index: 100;
	text-align: center;
	font-size: 10vw;

}

	
.lddc .sl-slider h2 {
	font-size: 100px;
	text-shadow: 0 -1px 0 rgba(0,0,0,0.2);
}

.lddc .sl-slider blockquote {
	padding-top: 10px;
	text-shadow: 0 -1px 0 rgba(0,0,0,0.2);
	font: 300 28px Impact, Haettenschweiler, "Franklin Gothic Bold", "Arial Black", sans-serif;
}

.lddc .sl-slider blockquote cite {
	font-size: 16px;
	font-weight: 700;
	font-style: normal;
	text-transform: uppercase;
	letter-spacing: 5px;
	padding-top: 30px;
	display: inline-block;
}

.lddc .bg-img {
	box-sizing: border-box;
	position: absolute;
	width: 100%;
	height: 100vh !important;
	-webkit-background-size: cover;
	-moz-background-size: cover;
	background-size: cover;
	background-position: center center;
	overflow: hidden;
		background-color: black;

}
/* Media Queries for custom slider */

	.lddc .sl-slider-wrapper {
	height: 800px;
	position: relative;
	top: 0px;
	}

	.lddc .sl-slider h2 {
		font-size: 36px;
	}

	.lddc .sl-slider blockquote {
		font-size: 16px;
	}

        <div class="container">

            <header class="lddc">

            
<div id="logo"><img src="images/logoblanc_cut.gif"  alt="" class="lddc logo"/></div>
<div id="slider" class="sl-slider-wrapper">

<div id="menu" class="navbar navbar-default navbar-fixed-top">
  <ul class="nav">
            <li><a href="#test">About</a></li>
            <li><a href="#">Blog</a></li>
            <li><a href="#">Product</a></li>
            <li><a href="#">Contact</a></li>
    </ul>
    </div>

	<div class="sl-slider" data-midnight="white">
				
					<div class="sl-slide" data-orientation="vertical">
						<div class="sl-slide-inner">
<div class="bg-img bg-img-1">
<h2>Regula aurea.</h2>
</div>
						</div>

						
			  </div>
					
	<div class="sl-slide" data-orientation="vertical"
				
					<div class="sl-slide" data-orientation="vertical">
						<div class="sl-slide-inner">
<div class="bg-img bg-img-2">
<video autoplay loop muted="" playsinline="">
    <source src="./videos/levres.webm"
            type="videos/webm">

    <source src="./videos/levres.mp4"
            type="video/mp4">
</video></div>		<h3>Titre
							<div class="marquee-rtl">    <!-- le contenu défilant -->
    <div>LeDav</div></h3>
						</div>
			  </div>
					
					<div class="sl-slide" data-orientation="vertical">
						<div class="sl-slide-inner">
<div class="bg-img bg-img-3">
<video autoplay loop muted="" playsinline="">
    <source src="./lddc.webm"
            type="video/webm">

    <source src="./videos/lddc.mp4"
            type="video/mp4">
</video></div>		<h2>Titre1</h2>
							<blockquote><p>Until he extends the circle of his compassion to all living things, man will not himself find peace.</p><cite>Albert Schweitzer</cite></blockquote>
						</div>
			  </div>
					<div class="sl-slide" data-orientation="vertical">
						<div class="sl-slide-inner">
<div class="bg-img bg-img-4">
<video autoplay loop muted="" playsinline="">
    <source src="/media/cc0-videos/lddc.webm"
            type="video/webm">

    <source src="./videos/lddc.mp4"
            type="video/mp4">
</video></div>		<h2>Titre2</h2>
							<blockquote><p>Until he extends the circle of his compassion to all living things, man will not himself find peace.</p><cite>Albert Schweitzer</cite></blockquote>
						</div>
			  </div>
			  					<div class="sl-slide" data-orientation="vertical">
						<div class="sl-slide-inner">
<div class="bg-img bg-img-1">
<video autoplay loop muted="" playsinline="">
    <source src="/media/cc0-videos/lddcrock.webm"
            type="video/webm">

    <source src="./videos/lddcrock.mp4"
            type="video/mp4">
</video></div>		<h2>Titre3</h2>
							<blockquote><p>Until he extends the circle of his compassion to all living things, man will not himself find peace.</p><cite>Albert Schweitzer</cite></blockquote>
						</div>
			  </div>
</div></div></div></header>