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CSS

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JavaScript

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HTML 

              
                <!--
  Checkbox Trickery with CSS:
  http://codersblock.com/blog/checkbox-trickery-with-css/ 
-->

<div class="container">
  <h1><span class="marvel">Marvel</span> Mutant Teams</h1>

  <input id="original" type="radio" name="team" checked>
  <label for="original">Original X-Men</label>

  <input id="force" type="radio" name="team">
  <label for="force">X-Force</label>

  <input id="factor" type="radio" name="team">
  <label for="factor">X-Factor</label>

  <input id="hellfire" type="radio" name="team">
  <label for="hellfire">Hellfire Club</label>
  
  <br>
  <ul class="characters">
    <li id="angel" data-teams="original force factor hellfire">
      <h2>Angel</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-angel.png" alt="">
    </li>
    <li id="beast" data-teams="original factor">
      <h2>Beast</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-beast.png" alt="">
    </li>
    <li id="cyclops" data-teams="original force factor">
      <h2>Cyclops</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-cyclops.png" alt="">
    </li>
    <li id="emma-frost" data-teams="hellfire">
      <h2>Emma Frost</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-emma-frost.png" alt="">
    </li>
    <li id="iceman" data-teams="original factor">
      <h2>Iceman</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-iceman.png" alt="">
    </li>
    <li id="jean-grey" data-teams="original factor">
      <h2>Jean Grey</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-jean-grey.png" alt="">
    </li>
    <li id="magneto" data-teams="hellfire">
      <h2>Magneto</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-magneto.png" alt="">
    </li>
    <li id="nightcrawler" data-teams="force">
      <h2>Nightcrawler</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-nightcrawler.png" alt="">
    </li>
    <li id="professor-x" data-teams="original">
      <h2>Professor X</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-professor-x.png" alt="">
    </li>
    <li id="psylocke" data-teams="force hellfire">
      <h2>Psylocke</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-psylocke.png" alt="">
    </li>
    <li id="quicksilver" data-teams="factor">
      <h2>Quicksilver</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-quicksilver.png" alt="">
    </li>
    <li id="rictor" data-teams="force factor">
      <h2>Rictor</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-rictor.png" alt="">
    </li>
    <li id="storm" data-teams="force hellfire">
      <h2>Storm</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-storm.png" alt="">
    </li>
    <li id="sunspot" data-teams="force hellfire">
      <h2>Sunspot</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-sunspot.png" alt="">
    </li>
    <li id="tithe" data-teams="hellfire">
      <h2>Tithe</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-tithe.png" alt="">
    </li>
    <li id="wolverine" data-teams="force">
      <h2>Wolverine</h2>
      <img src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/77020/ct-wolverine.png" alt="">
    </li>
  </ul>
</div>
!

CSS 

              
                @import url(https://fonts.googleapis.com/css?family=Oswald:400,700);

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

body {
  margin: 0;
  color: #fff;
  background-color: #444;
  font: 0/1 'Oswald', sans-serif;
  text-align: center;
}

.container {
  margin: 0 auto;
  padding: 20px 5px;
}

h1 {
  margin: 0 5px 15px;
  font-size: 45px;
  line-height: 1.2;
  text-transform: uppercase;
  text-shadow: 0 0 20px #000;
}

.marvel {
  color: #c00;
}

input {
  position: absolute;
  left: -9999px;
}

label {
  display: inline-block;
  position: relative;
  width: 150px;
  margin: 5px;
  padding: 10px 10px 10px 38px;
  background-color: #000;
  font-size: 18px;
  white-space: nowrap;
  cursor: pointer;
}

label::before {
  content: '';
  display: block;
  position: absolute;
  top: 10px;
  left: 10px;
  width: 18px;
  height: 18px;
  border: 2px solid #fff;
  background-color: #444;
}

input:focus + label {
  outline: 1px solid #fff;
}

input:checked + label::before {
  background-color: #c00;
}

/* width is controlled here and in media queries to ensure that there's always an even number of columns (prevents orphans) */
.characters {
  display: inline-block;
  width: 240px;
  list-style-type: none;
  margin: 15px -5px 0;
  padding: 0;
}

.characters li {
  display: inline-block;
  position: relative;
  margin: 10px;
  padding: 0;
  width: 100px;
  height: 100px;
}

.characters h2 {
  display: none;
  position: absolute;
  z-index: 2;
  top: 70px;
  left: 0px;
  right: 0px;
  margin: 0;
  padding: 4px;
  border: 1px solid #fff;
  color: #fff;
  background-color: #000;
  font-size: 14px;
  font-weight: normal;
}

.characters img {
  width: 100px;
  height: 100px;
  border: 4px solid #fff;
  border-radius: 50%;
  background-color: #fff;
  box-shadow: 0 0 20px #000;
  opacity: .25;
  transform: scale(.5);
}

#original:checked ~ .characters [data-teams~="original"] h2,
#force:checked ~ .characters [data-teams~="force"] h2,
#factor:checked ~ .characters [data-teams~="factor"] h2,
#hellfire:checked ~ .characters [data-teams~="hellfire"] h2 {
  display: block;
}

#original:checked ~ .characters [data-teams~="original"] img,
#force:checked ~ .characters [data-teams~="force"] img,
#factor:checked ~ .characters [data-teams~="factor"] img,
#hellfire:checked ~ .characters [data-teams~="hellfire"] img {
  animation: avatar .3s forwards;
}

/* fade in and expand image to full size, with a slight bounce */
@keyframes avatar {
  70% {
    opacity: 1;
    transform: scale(1.1);
  }
  100% {
    opacity: 1;
    transform: scale(1);
  }
}

@media only screen and (min-width: 500px) {
  .characters {
    width: 480px;
  }
}

@media only screen and (min-width: 740px) {
  .characters {
    width: 720px;
  }

  h1 {
    font-size: 60px;
  }
}

@media only screen and (min-width: 980px) {
  .characters {
    width: 960px;
  }
}
!

JS
!
999px

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