.conteneur{
  overflow: hidden;
}
.conteneur-flex{
  display: flex;
  flex-wrap: wrap;
  background-color: 
  RGBa(80,130,180,0.7);
  margin-bottom: 20px;
}
.element-flex{
  background-color: 
  RGBa(80,180,130,0.7);
  width: 50px;
  height: 50px;
  border: 2px solid green;
}
.marge{
  margin: 0px 10px;
}
.margeneg{
  margin: 
  0px -10px 20px -10px;
}
.gouttiere{
  column-gap: 10px;
}