resize.css

div {
  position: relative;
  min-width: 50px;
  min-height: 50px;
  margin: 10px;
  background: lightblue;
  border: 1px solid #ccc;
}

.resize-border {
  position: absolute;
  background: transparent;
  z-index: 1000;
  padding: 0;
  margin: 0;
  min-width: 0;
  min-height: 0;
  border: none;
  background: transparent !important;
}

.resize-border.top,
.resize-border.bottom {
  height: 10px;
  left: 0;
  right: 0;
  cursor: ns-resize;
}

.resize-border.top {
  top: -5px;
}

.resize-border.bottom {
  bottom: -5px;
}

.resize-border.left,
.resize-border.right {
  width: 10px;
  top: 0;
  bottom: 0;
  cursor: ew-resize;
}

.resize-border.left {
  left: -5px;
}

.resize-border.right {
  right: -5px;
}

div:hover {
  outline: 2px dashed #666;
}


.rsize{
  display: flex;
  flex-direction: row;
}