tabs css only

* {
  box-sizing: border-box;
}

body {
  padding: 10px;
  background: #f2f2f2;
}

.tabs {
  display: flex;
  flex-wrap: wrap;
  max-width: 700px;
  background: #efefef;
  box-shadow: 0 48px 80px -32px rgba(0,0,0,0.3);
}

.input {
  position: absolute;
  opacity: 0;
}

<div class="tab content1">Tab1 Contents</div><div class="tab content2">Tab2 Contents</div><div class="tab content3">Tab3 Contents</div><div class="tab content4">Tab4 Contents</div><div class="tab content5">Tab5 Contents</div>