Fenêtres modales - Problème de CSS

Bonsoir,
Je travaille actuellement sur une page avec 3 "boutons" ouvrant chacun une fenêtre modale. Le problème est que les fenêtres liées aux 2 premiers "boutons" s'empilent (les deux sont visibles). Seul la troisième fenêtre s'affiche correctement. Si j'applique un fond noir à la classe des fenêtres, seul la troisième fenêtre est visible (quelque soit le bouton). J'ai tenté de rajouter des classes... rien à faire. Surement quelque chose de stupide. Voici les CSS d'origine :

.cd-modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  visibility: hidden;
  opacity: 0;
  pointer-events: none;
  -webkit-transition: visibility 0s 0.3s, opacity 0.3s 0s, z-index 0s 0.3s;
  -moz-transition: visibility 0s 0.3s, opacity 0.3s 0s, z-index 0s 0.3s;
  transition: visibility 0s 0.3s, opacity 0.3s 0s, z-index 0s 0.3s;
}
.cd-modal::after {
  /* gradient overlay at bottom of modal window */
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 60px;
  pointer-events: none;
  background: transparent;
  background: -webkit-linear-gradient( bottom , #34383c, rgba(52, 56, 60, 0));
  background: linear-gradient(to top, #34383c, rgba(52, 56, 60, 0));
}
.cd-modal .cd-modal-content {
  height: 100%;
  width: 100%;
  padding: 3em 5%;
  text-align: left;
  overflow-y: auto;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
.cd-modal p {
  color: #ffffff;
  line-height: 1.6;
  margin: 2em 0;
}
.modal-is-visible .cd-modal {
  z-index: 1;
  visibility: visible;
  opacity: 1;
  pointer-events: auto;
  -webkit-transition: visibility 0s 0s, opacity 0.3s 0s, z-index 0s 0s;
  -moz-transition: visibility 0s 0s, opacity 0.3s 0s, z-index 0s 0s;
  transition: visibility 0s 0s, opacity 0.3s 0s, z-index 0s 0s;
}
.modal-is-visible .cd-modal .cd-modal-content {
  -webkit-overflow-scrolling: touch;
}
@media only screen and (min-width: 768px) {
  .cd-modal .cd-modal-content {
    padding: 4em 10%;
  }
}
@media only screen and (min-width: 1170px) {
  .cd-modal .cd-modal-content {
    padding: 6em 20%;
  }
  .cd-modal p {
    font-size: 2rem;
    line-height: 2;
  }
}

.cd-modal-action {
  position: relative;
}
.cd-modal-action .btn, .cd-modal-action .cd-modal-bg {
  display: inline-block;
  height: 4em;
  background-color: #34383c;
}
.cd-modal-action .btn {
  width: 12.5em;
  border-radius: 0em;
  color: #ffffff;
  line-height: 4em;
  white-space: nowrap;
  font-weight: 700;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  -webkit-transition: color 0.2s 0.3s, width 0.3s 0s;
  -moz-transition: color 0.2s 0.3s, width 0.3s 0s;
  transition: color 0.2s 0.3s, width 0.3s 0s;
}
.cd-modal-action .btn.to-circle {
  width: 4em;
  color: transparent;
  -webkit-transition: color 0.2s 0s, width 0.3s 0.2s;
  -moz-transition: color 0.2s 0s, width 0.3s 0.2s;
  transition: color 0.2s 0s, width 0.3s 0.2s;
}
.cd-modal-action .cd-modal-bg {
  position: absolute;
  z-index: 1;
  left: 50%;
  top: 0;
  width: 4em;
  border-radius: 0em;
  opacity: 0;
  visibility: hidden;
  -webkit-transform: translateZ(0);
  -moz-transform: translateZ(0);
  -ms-transform: translateZ(0);
  -o-transform: translateZ(0);
  transform: translateZ(0);
  -webkit-transform: translateX(-2em);
  -moz-transform: translateX(-2em);
  -ms-transform: translateX(-2em);
  -o-transform: translateX(-2em);
  transform: translateX(-2em);
  -webkit-transition: visibility 0s 0.15s;
  -moz-transition: visibility 0s 0.15s;
  transition: visibility 0s 0.15s;
}
.cd-modal-action .cd-modal-bg.is-visible {
  opacity: 1;
  visibility: visible;
}

.cd-modal-close {
  position: fixed;
  z-index: 1;
  top: 20px;
  right: 5%;
  height: 50px;
  width: 50px;
  border-radius: 50%;
  background: rgba(0, 0, 0, 0.3) url(../img/cd-icon-close.svg) no-repeat center center;
  /* image replacement */
  overflow: hidden;
  text-indent: 100%;
  white-space: nowrap;
  visibility: hidden;
  opacity: 0;
  -webkit-transform: translateZ(0);
  -moz-transform: translateZ(0);
  -ms-transform: translateZ(0);
  -o-transform: translateZ(0);
  transform: translateZ(0);
  -webkit-transform: scale(0);
  -moz-transform: scale(0);
  -ms-transform: scale(0);
  -o-transform: scale(0);
  transform: scale(0);
  -webkit-transition: -webkit-transform 0.3s 0s, visibility 0s 0.3s, opacity 0.3s 0s;
  -moz-transition: -moz-transform 0.3s 0s, visibility 0s 0.3s, opacity 0.3s 0s;
  transition: transform 0.3s 0s, visibility 0s 0.3s, opacity 0.3s 0s;
}
.no-touch .cd-modal-close:hover {
  background-color: rgba(0, 0, 0, 0.5);
}
.modal-is-visible .cd-modal-close {
  visibility: visible;
  opacity: 1;
  -webkit-transition: -webkit-transform 0.3s 0s, visibility 0s 0s, opacity 0.3s 0s;
  -moz-transition: -moz-transform 0.3s 0s, visibility 0s 0s, opacity 0.3s 0s;
  transition: transform 0.3s 0s, visibility 0s 0s, opacity 0.3s 0s;
  -webkit-transform: scale(1);
  -moz-transform: scale(1);
  -ms-transform: scale(1);
  -o-transform: scale(1);
  transform: scale(1);
}
@media only screen and (min-width: 768px) {
  .cd-modal-close {
    top: 70px;
  }
}

et le html concerné :

		<[/contents/242-introduction-au-dynamic-html-dhtml div] class="cd-modal">
			<div class="cd-modal-content">
				<p>
				Test1
				</p>	
			</div> <!-- cd-modal-content -->
		</div> <!-- cd-modal -->
        		<div class="cd-modal-action">
			<a href="#0" class="btn" data-type="modal-trigger">test-2</a>
			<span class="cd-modal-bg"></span>
		</div> <!-- cd-modal-action -->

		<div class="cd-modal">
			<div class="cd-modal-content">
				<p>
				Test2
				</p>
			</div> <!-- cd-modal-content -->
		</div> <!-- cd-modal -->
        		<div class="cd-modal-action">
			<a href="#0" class="btn" data-type="modal-trigger">test-3</a>
			<span class="cd-modal-bg"></span>
		</div> <!-- cd-modal-action -->

		<div class="cd-modal">
			<div class="cd-modal-content">
				<p>
				Test3
				</p>
			</div> <!-- cd-modal-content -->
		</div> <!-- cd-modal -->

Je pense que c'est tout bête, mais je n'ai pas trouvé la solution :/
Merci pour votre aide,
E.