.wrapperBackground {
  position: fixed;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;
}

.background {
  position: absolute;
  max-width:100%;
  max-height:100%;
  z-index:-1;
}
.input-file-container {
  position: absolute;
  width: 750px;
  top: 100px;

} 
.js .input-file-trigger {
  display: block;
  padding: 14px 45px;
  background: #39D2B4;
  color: #fff;
  font-size: 3em;
  transition: all .4s;
  cursor: pointer;
}
.js .input-file {
  position: absolute;
  top: 0; left: 0;
  width: 750px;
  opacity: 0;
  padding: 14px 0;
  cursor: pointer;
}
.js .input-file:hover + .input-file-trigger,
.js .input-file:focus + .input-file-trigger,
.js .input-file-trigger:hover,
.js .input-file-trigger:focus {
  background: #34495E;
  color: #39D2B4;
}

.file-return {
  margin: 0;
  background: #34495E;
  color: #39D2B4;
}
.file-return:not(:empty) {
  margin: 1em 0;
}
.js .file-return {
  font-style: italic;
  font-size: 2em;
  font-weight: bold;
}
.js .file-return:not(:empty):before {
  content: "Veuillez patienter : ";
  font-style: normal;
  font-weight: normal;
}




/* Useless styles, just for demo styles */

body {
  font-family: "Open sans", "Segoe UI", "Segoe WP", Helvetica, Arial, sans-serif;
  color: #7F8C9A;
  background: #FCFDFD;
}
h1, h2 {
  margin-bottom: 5px;
  font-weight: normal;
  text-align: center;
  color:#aaa;
}
h2 {
  margin: 5px 0 2em;
  color: #1ABC9C;
}
form {
  width: 750px;
  margin: 0 auto;
  text-align:center;
}
h2 + P {
  text-align: center;
}
.txtcenter {
  margin-top: 4em;
  font-size: .9em;
  text-align: center;
  color: #aaa;
}
.copy {
  margin-top: 2em;
}
.copy a {
  text-decoration: none;
  color: #1ABC9C;
}