Bonjour à tous,

J'ai fais mes bloc pas encore fini, je voudrais savoir comment faire pour annuler les valeurs négatif dans mon css.

Merci beaucoup


<!DOCTYPE html>
<html>
<head>
	<meta charset="UTF-8" />
	<meta name="viewport" content="width=device-width, initial-scale=1" />

		<title>Eshop essai</title>
			<link rel="stylesheet" href="css/bootstrap.css" />
			<link rel="stylesheet" href="bootstrap2.css" />
</head>			
<body>

<div id="conteneur" class="container text-center">

		<div class="a">
			<div class="hautgauche"> <img src="img/ElementE.jpg" alt="image"/> </div>
				<div class="prix1">
					<span>Carreaux de ciment imitations</span>
						<p>19,99 € TTC / m2</p></div>
					<div class="voir">
						<h1>Voir le produit</h1></div>
							<div class="ajout">
								<h1>Ajout au panier</h1></div>
									<div class="devis">
										<h1>Demande de devis personnalisé</h1></div>
		</div>
		
		<div class="b">
			<div class="millieuhaut"><img src="img/ElementF.jpg" alt="image"/></div>
				<div class="prix2">
					<span>Carreaux de ciment imitations</span>
						<p>19,99 € TTC / m2</p></div>
					<div class="voir">
						<h1>Voir le produit</h1></div>
							<div class="ajout"><h1>Ajout au panier</h1></div>
								<div class="devis">
									<h1>Demande de devis personnalisé</h1></div>
		</div>
			
		<div class="c">
			<div class="hautdroit"><img src="img/ElementG.jpg" alt="image"/></div>
				<div class="prix3">
					<h1>Carreaux de ciment imitations</h1>
						<p>19,99 € TTC / m2</p></div>
					<div class="voir">
						<h1>Voir le produit</h1></div>
							<div class="ajout"><h1>Ajout au panier</h1></div>
								<div class="devis">
									<h1>Demande de devis personnalisé</h1></div>
			
		
		<div class="d">
			<div class="basgauche"><img src="img/ElementH.jpg" alt="image"/></div>
				<div class="prix4">
					<span>Carreaux de ciment imitations</span>
						<p>19,99 € TTC / m2</p></div>
					<div class="voir">
						<h1>Voir le produit</h1></div>
							<div class="ajout">
								<h1>Ajout au panier</h1></div>
									<div class="devis">
										<h1>Demande de devis personnalisé</h1></div>
		</div>
		
		<div class="e">
			<div class="millieubas"><img src="img/ElementI.jpg" alt="image"/></div>
				<div class="prix5">
				<span>Carreaux de ciment imitations</span>
						<p>19,99 € TTC / m2</p></div> 
					<div class="voir">
						<h1>Voir le produit</h1></div>
							<div class="ajout">
								<h1>Ajout au panier</h1></div>
									<div class="devis">
										<h1>Demande de devis personnalisé</h1></div>
		</div>
		
		<div class="f">
		
			<div class="basdroit"><img src="img/ElementJ.jpg" alt="image"/></div>
				<div class="prix6">
					<span>Carreaux de ciment imitations</span>
						<p>19,99 € TTC / m2</p></div>
					<div class="voir">
						<h1>Voir le produit</h1></div>
							<div class="ajout">
								<h1>Ajout au panier</h1></div>
									<div class="devis">
										<h1>Demande de devis personnalisé</h1></div>
		</div>
</div>	


<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
</body>
</html>



/*  http://meyerweb.com/eric/tools/css/reset/  
   v2.0 | 20110126
   License: none (public domain)
*/

html, body, div, span, applet, object, iframe,
h1, h2, h3, h4, h5, h6, p, blockquote, pre,
a, abbr, acronym, address, big, cite, code,
del, dfn, em, img, ins, kbd, q, s, samp,
small, strike, strong, sub, sup, tt, var,
b, u, i, center,
dl, dt, dd, ol, ul, li,
fieldset, form, label, legend,
table, caption, tbody, tfoot, thead, tr, th, td,
article, aside, canvas, details, embed, 
figure, figcaption, footer, header, hgroup, 
menu, nav, output, ruby, section, summary,
time, mark, audio, video {
	margin: 0;
	padding: 0;
	border: 0;
	font-size: 100%;
	font: inherit;
	vertical-align: baseline;
}
/* HTML5 display-role reset for older browsers */
article, aside, details, figcaption, figure, 
footer, header, hgroup, menu, nav, section {
	display: block;
}
body {
	line-height: 1;
}
ol, ul {
	list-style: none;
}
blockquote, q {
	quotes: none;
}
blockquote:before, blockquote:after,
q:before, q:after {
	content: '';
	content: none;
}
table {
	border-collapse: collapse;
	border-spacing: 0;
}

body{
	margin: 0 auto;
	padding: 20px;

}

.fond_rouge{background: red;}
.fond_rose{background: pink;}
.fond_bleu{background: blue;}
.fond_orange{background: orange;}
.fond_lime{background: lime;}
.fond_violet{background: purple;}
.fond_bleu{background: blue;}
.fond_rouge{background: red;}
.fond_orange{background: orange;}
.fond_jaune{background: yellow ;}
.fond_bleu{background: blue;}
.fond_vert{background: green;}
.fond_gris{background: grey;}


#conteneur{
	width: 100%;
	height: 1000px;
		
}

.a{
	max-height: 100%;
	width: 288px;
	height: 176px;
	background: red;
	float: left;
}
.prix1{
	margin-top: -3px;
	width: 288px;
	height: 86px;
	background: pink;
	float: left;
	
}
span{
	font-family: sans-serif;
	line-height: 3;
}

p{
	font-family: sans-serif;
	color: #f62775;
}

.voir{
	
	margin-top: 0px;
	width: 144px;
	height: 27px;
	background: orange;
	float: left;
	color: white;

	
}
h1{
	font-family: sans-serif;
	line-height: 1.5;
}
.ajout{
	margin-top: -27px;
	margin-left: 144px;
	width: 144px;
	height: 27px;
	background: grey;
	float: left;
	color: white;
}

.devis{
	margin-top: 0px;
	width: 288px;
	height: 27px;
	background: lime;
	float: left;
	
}


.b{
	margin-left: 100px;
	width: 288px;
	height: 176px;
	background: blue;
	float: left;
}
.prix2{
	margin-top: -3px;
	width: 288px;
	height: 86px;
	background: pink;
	float: left;
	
}

.c{
	margin-left: 100px;
	width: 288px;
	height: 176px;
	background: green;
	float: left;
}
.prix3{
	margin-top: -3px;
	width: 288px;
	height: 86px;
	background: pink;
	float: left;
	
}

.clear{
	float: left;
}

.d{
	margin-left: -777px;
	margin-top: 165px;
	width: 288px;
	height: 176px;
	background: red;

}
.prix4{
	margin-top: -3px;
	width: 288px;
	height: 86px;
	background: pink;
	float: left;
	
}


.e{
	margin-left: -389px;
	margin-top: -289px;
	width: 288px;
	height: 176px;
	background: blue;
	float: left;
}
.prix5{
	margin-top: -3px;
	width: 288px;
	height: 86px;
	background: pink;
	float: left;
	
}


.f{

	margin-top: -289px;
	width: 288px;
	height: 176px;
	background: green;
	float: left;
}
.prix6{
	margin-top: -3px;
	width: 288px;
	height: 86px;
	background: pink;
	float: left;
	
}
.clear{
	float: left;
}