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

body {
  font-family: sans-serif; }
.particles {
  background: rgba(102, 51, 153, 0.1);
  height: 400px;
  margin: 10px auto;
  overflow: hidden;
  position: relative;
  width: 90%; }
.particle {
  background: url(../res/seahorse.svg) no-repeat center center #aaa;
  background-size: 20px 20px;
  border-radius: 10px;
  color: #fff;
  height: 20px;
  line-height: 20px;
  margin: -10px 0 0 -10px;
  position: absolute;
  text-align: center;
  width: 20px;
  z-index: 1; }
  .particle.has-vision::after {
    border: 50px solid;
    border-color: lightgreen transparent transparent turquoise;
    border-radius: 50px;
    content: ' ';
    height: 0;
    left: -50px;
    margin: 10px 0 0 10px;
    opacity: 0.5;
    position: absolute;
    transform: rotate(45deg);
    top: -50px;
    width: 0; }

.particle-movement-circle {
  border: 2px dotted darkturquoise;
  position: absolute;
  transition: left 0.2s, top 0.2s, height 0.2s, width 0.2s;
  z-index: 0; }
  .particle-movement-circle:after {
    background: darkturquoise;
    border-radius: 2px;
    content: ' ';
    height: 4px;
    left: 50%;
    margin-left: -2px;
    margin-top: -2px;
    position: absolute;
    top: 50%;
    width: 4px; }