Fix x_axis and fill under the Bokeh curve

I am trying to tweak my Python Bokeh plots to look a little better. For example, is there a way to fix the maximum decrease? So Bokeh can't zoom out more than the x-axis? For example. take a look at the bokeh example , and especially Datetime Dots. I would like to correct the size of the axis so that you cannot zoom out more than the start x axis is wide.

Another question; is there a way to fill the area under the curve in the specified color? As in the USDSEK figure . I can provide the code, but I don't think it is necessary for the problem.