Draw Koch snowflake with tkinter

Koch snowflake is probably the simplest fractal graphic. The fractal idea is to draw a straight line segment, $x_0-x_1$, and make the trisection points $x_{1/3}$ and $x_{2/3}$. Then replace the segment $x_{1/3}-x_{2/3}$ with a equilateral triangle, like the image below. [more]

CSS layout

The following describes some important CSS attributes to layout elements on a page. [more]