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<link href='https://fonts.googleapis.com/css?family=Open+Sans:400,700' rel='stylesheet' type='text/css'>

<h1>CSS Only Carnival: Target Practice</h1>
<h2>This game uses no JS at all (isn't CSS awesome?). You have 8 seconds to hit as many targets as you can!</h2>

<div class="game-over">
  <h1>Game Over!</h1>
  <a class="play-again" target="_parent" href="https://codepen.io/una/full/NxZaNr">Play Again</a>
</div>

<ul class="game-area">
  <li><input type="checkbox"><div class="shield"></div></li>
  <li><input type="checkbox"><div class="shield"></div></li>
  <li><input type="checkbox"><div class="shield"></div></li>
  <li><input type="checkbox"><div class="shield"></div></li>
  <li><input type="checkbox"><div class="shield"></div></li>
  <li><input type="checkbox"><div class="shield"></div></li>
  <li><input type="checkbox"><div class="shield"></div></li>
  <li><input type="checkbox"><div class="shield"></div></li>
  <li><input type="checkbox"><div class="shield"></div></li>
</ul>

<h3 class="total-count">Targets Hit: &nbsp;</h3>

<small><a href="https://twitter.com/<una</una>">Made with love by @una &hearts;</a></small>
* {
  box-sizing: border-box;
}

h1 {
  font-size: 1.4em;
}

body {
  counter-reset: game;
  text-align: center;
  background: #e9b58b;
  font-family: 'Open Sans', 'Helvetica', 'Arial', sans-serif;
  color: #333;
}

input:checked {
  counter-increment: game;
}

.total-count::after {
  content: counter(game);
}

h2 {
  font-size: 1em;
  margin: -.5em auto 3em;
  font-weight: 400;
}

.total-count {
  font-size: 1.75em;
  position: absolute;
  top: 1.75em;
  width: 100%;
  left: 0;
  text-align: center;
  z-index: 300;
}

.game-area {
  display: flex;
  flex-flow: wrap;
  align-items: center;
  justify-content: space-between;
  max-width: 600px;
  min-height: 550px;
  max-height: 700px;
  margin: 0 auto;
  padding-left: 0; //list reset
}

li {
  width: calc(33% - .5em);
  margin-bottom: 1em;
  height: 10em;
  list-style: none;
  position: relative;
  outline: 4px solid white;
  background: #64ddf3;

  @for $i from 1 through 9 {
    $speed: random()*5 + 's';
    $color-hue: random()*360 + 'deg';
    $brightness: random() + 1;

    &:nth-child(#{$i}) {
      input {
        filter: hue-rotate(#{$color-hue}) brightness(#{$brightness});
        animation-duration: #{$speed};
      }
    }
  }
}

input[type="checkbox"] {
  width: 50px;
  height: 50px;
  position: absolute;
  cursor: crosshair;
  background: radial-gradient(red 10%, white 10%, white 30%, red 30%, red 50%, white 50%, white 80%, red 80%, red 100%);
  border-radius: 50%;
  display: block;
  left: 0;
  right: 0;
  text-align: center;
  margin: 0 auto;
  appearance: none;
  border: 6px solid red;
  animation: hide-target infinite alternate ease-in-out;
  z-index: 1;

  &:before {
    content: '';
    display: block;
    background-color: black;
    height: 50%;
    width: 6px;
    position: absolute;
    left: 0; right: 0;
    top: calc(100% + 6px);
    margin: 0 auto;
    z-index: -1;
  }

  &:focus {
    outline: none;
    appearance: none;
  }


  &:checked {
    pointer-events: none;
    filter: grayscale(1) opacity(.75);
    animation: none;

    &:after {
      content: '+1!';
      padding: .5em;
      margin: 1em 0 0 1.5em;
      font-size: 2.5em;
      font-weight: 600;
    }
  }
}

.shield {
  background: #724c20;
  width: 100%;
  height: 60%;
  margin: 0 auto;
  bottom: 0;
  left: 0; right: 0;
  position: absolute;
  pointer-events: all;
  z-index: 100;
}

@keyframes hide-target {
  0% {
    top: 0
  }
  25% {
    top: 50%
  }
  100% {
    top: 0
  }
}

.game-over {
  height: 100%;
  width: 100%;
  display: block;
  background: white;
  pointer-events: all;
  position: absolute;
  top: -100%;
  left: 0;
  z-index: 200;
  animation: appear .25s forwards;
  animation-delay: 8s;
  background: repeating-linear-gradient(-45deg, #c9ff00 0, #c9ff00 5em, #20c0ff 5em, #20c0ff 10em);

  h1 {
    padding: 1em 0 3.5em;
    background: white;
  }
}

@keyframes appear {
  from {
    top: -100vh;
    opacity: 0;
  }
  to {
    top: 0;
    opacity: 1;
  }
}

.play-again {
  background: white;
  color: #20c0ff;
  padding: .5em 1em;
  font-size: 2.5em;
  font-weight: 700;
}

small a {
  margin-bottom: 2em;
  display: block;
  color: #222;
}
View Compiled
// Look ma, NO JS! Or images... or even SVGs either :P
Rerun