*, *:before, *:after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

main {
  min-width: 320px;
  max-width: auto;  
  margin: 0 auto;
  background: #fff;
}

section.tab {
  display: none;
  padding: 20px 0 0;
  border-top: 1px solid #ddd;
}

input.tab {
  display: none;
}

label.tab {
  display: inline-block;
  margin: 0 0 -1px;
  padding: 5px 10px;
  font-weight: 200;
  text-align: center;
  color: #bbb;
  border: 1px solid transparent;
}

label.tab:before {
  font-family: fontawesome;
  font-weight: normal;
  margin-right: 10px;
}

label.tab:hover {
  color: #888;
  cursor: pointer;
}

input.tab:checked + label {
  color: #555;
  border: 1px solid #ddd;
  border-top: 2px solid orange;
  border-bottom: 1px solid #fff;
}

/* 21 tabs at max including zero */
#tab0:checked ~ #content0,
#tab1:checked ~ #content1,
#tab2:checked ~ #content2,
#tab3:checked ~ #content3,
#tab4:checked ~ #content4,
#tab5:checked ~ #content5,
#tab6:checked ~ #content6,
#tab7:checked ~ #content7,
#tab8:checked ~ #content8,
#tab9:checked ~ #content9,
#tab10:checked ~ #content10,
#tab11:checked ~ #content11,
#tab12:checked ~ #content12,
#tab13:checked ~ #content13,
#tab14:checked ~ #content14,
#tab15:checked ~ #content15,
#tab16:checked ~ #content16,
#tab17:checked ~ #content17,
#tab18:checked ~ #content18,
#tab19:checked ~ #content19,
#tab20:checked ~ #content20{
  display: block;
}

@media screen and (max-width: 650px) {
  label.tab {
    font-size: 0;
  }
  label.tab:before {
    margin: 0;
    font-size: 18px;
  }
}

@media screen and (max-width: 400px) {
  label.tab {
    padding: 15px;
  }
}