.edge.level0{stroke-width:3px;fill:none;stroke:#47f;stroke-linejoin:round;stroke-linecap:round}.edge.level1{stroke-width:4px;fill:none;stroke-linejoin:round;stroke-linecap:round}.edge.level2{stroke-width:3px;fill:none;stroke-linejoin:round;stroke-linecap:round}.node-underline.level1{stroke-linecap:round;stroke-width:8px}.node-underline.level2{stroke-linecap:round;stroke-width:3px}.collapse-button{cursor:pointer}