selectlayer.css

div#ks-editor #select-layer {
    position: relative;
}

div#ks-editor #box-select {
    position: absolute;
    z-index: 300000;
    border-style: dotted;
    border-color: rgba(0, 0, 0, 0);
    border-width: 2px;
    background-color: rgba(0, 0, 0, 0);
    pointer-events: none;

    -webkit-transition-property: border-color, background-color;
    -moz-transition-property: border-color, background-color;
    -o-transition-property: border-color, background-color;
    transition-property: border-color, background-color;

    -webkit-transition-duration: 200ms;
    -moz-transition-duration: 200ms;
    -o-transition-duration: 200ms;
    transition-duration: 200ms;
}

div#ks-editor #box-select.visible {
    border-color: #3e74cc;
    background-color: rgba(255, 255, 255, 0.5);
}