main.css

* {
  margin: 0;
  padding: 0;
}

html, body {
  width: 100%;
  height: 100%;
}

.sidepane {
  height: 100%;
  background: #E8E8EA;
}

.sidepane .form {
  height: 80px;
  margin: 10px 0;
}

.sidepane .assets {
  width: 100%;
}

#assetText {
  font-size: 24px;
}

.assets .text, .assets .image {
  margin: 10px 0;
}
.assets .image ul li {
  width: 50px;
  height: 50px;
  margin-right: 5px;
  float: left;
  overflow: hidden;
}
.assets .image ul li img {
  width: 100%;
  height: 100%;
}

.canvas .block {
  position: relative;
  width: 600px; height: 600px;
  margin: 10px;
  border: 1px solid;
  box-shadow: 0px 0px 5px black;
  overflow: auto;
}

.item {
  border: 1px solid transparent;
  position: absolute;
}

.item.selected {
  border-color: blue;
}