Project: draw
Task (easy): Add toolkit container (class 'toolkit') and svg element (class 'canvas')  in '.root'. toolkit and canvas together fill the whole space of the browser element. Add shape container (class 'shape'), prop container (class 'prop') and operation container (class 'operation') horizontally in the toolkit. shape container (3 labels width) is at the toolkit's left side. operation container (6 labels width) is at the toolkit's right side. prop container occupies the toolkit's remaining space. Add a line width input (class 'line-width', value from 1 to 21, default is 9) in the prop container. Add a color selector input (class 'color', default is #000000) in the prop container.