$dark:   #262626;
$light:  #dcdcd2;
$vsize:  400px;
$shift:  8px;
$timing: cubic-bezier(.30,.1,.30,1);

@function toggle($value, $first, $second) {
  @if $value == $first {
    @return $second;
  } @else {
    @return $first;
  }
}

@keyframes wobble {
  0% {
    transform: translateX(-$shift);
  }

  50% {
    transform: translateX($shift);
  }

  100% {
    transform: translateX(-$shift);
  }
}

@mixin circles($num) {
  $color: $light;
  $size:  35px;
  $sadd:  25px;
  $wait:  0s;
  @for $current from $num through 1 {
    div.circle:nth-of-type(#{$current}) {
      @if $current % 2 == 0 {
        background: $light;
      } @else {
        background: $dark;
        animation: wobble 1.8s infinite $timing;
        animation-delay: $wait;
      }

      width: $size;
      height: $size;
      left: (200 - ($size / 2));
      top: (200 - ($size / 2));
    }

    $size: $size + $sadd;
    $sadd: toggle($sadd, 25px, 35px);
    $wait: $wait + 0.1s;
  }
}

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

html, body {
  padding: 0;
  margin: 0;
}

body {
  background: #202020;
  font-family: Roboto;
  color: #454545;
  a {
    text-decoration: none;
    color: #9a9a9a;

    &:hover {
      color: #ffffff;
    }
  }
}

#note {
  text-align: center;
  width: $vsize;
  position: absolute;
  margin-top: 410px;
}

#box {
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  box-shadow: 0px 0px 10px rgba(0, 0, 0, 0.5);
  position: absolute;
  background: $dark;
  width: $vsize;
  height: $vsize;

  #wrap {
    @include circles(19);
    
    width: 400px;
    height: 400px;
    overflow: hidden;
    position: absolute;
    div.circle {
      position: absolute;
      border-radius: 50%;

      &:nth-of-type(odd) {
        transform: translateX(-$shift);
      }
    }
  }
}