.box-container{border:2px solid #000;background-color:#949494;position:relative;border-radius:5px;background-color:#e0e0e0}.box-container .box-header{height:10px;width:100%;border-top-left-radius:5px;border-top-right-radius:5px}.box-container .box-content{overflow:hidden;font-weight:700;height:40px;display:flex;justify-content:space-between;align-items:center;padding:5px}.box-container.selected{border:2px solid blue;position:relative}.box-container.selected .corner{width:8px;height:8px;background-color:blue;position:absolute}.box-container.selected .corner.top-left{top:-4px;left:-4px;cursor:nwse-resize}.box-container.selected .corner.top-right{top:-4px;right:-4px;cursor:nesw-resize}.box-container.selected .corner.bottom-left{bottom:-4px;left:-4px;cursor:nesw-resize}.box-container.selected .corner.bottom-right{bottom:-4px;right:-4px;cursor:nwse-resize}.box-content{font-size:14px;color:#333}.canvas{position:relative;width:100%;height:100%;background-color:#f0f0f0;background-image:radial-gradient(circle,#000 1px,transparent 0);background-size:20px 20px}.properties-panel{width:300px;padding:10px;background-color:#f8f8f8;border-right:1px solid #ddd;box-sizing:border-box}.properties-panel input{width:100%}.properties-error{padding:10px;background-color:#f2dede;border:1px solid #000}