如何通过填充正确遮盖多个重叠图？

Question

I have a figure where I wish to fill under each plot to obscure the plots behind it.

My desired result is akin to this example:

I think I need to set the zorder of either plot or fill_between (or both?), but I can't seem to get the correct combinations.

My current plot and code are below.

My current code:

import numpy as np
import matplotlib.pyplot as plt


def gaussian(x, mu, sig):
    return np.exp(-(x - mu)*(x - mu) / (2 * sig*sig))


mus = [4, 3, 2, 1, 0, -1, -2, -3, -4]
x = np.linspace(-10, 10, 500)

for i in range(len(mus) - 1, -1, -1):
    mu = mus[i]
    y = gaussian(x, mu, 1) + i * 0.1
    plt.plot(x, y)
    plt.fill_between(x, y, 0, color="lightgray")  # The plot lines are not hidden by the fill. Probably need to do something with zorder

plt.show()

Answer 1

and of course, I find the answer after I ask...

for i in range(len(mus) - 1, -1, -1):
    mu = mus[i]
    y = gaussian(x, mu, 1) + i * 0.1
    zorder = len(mus) - i #zorder increases as I draw the plots "in front"
    plt.plot(x, y, zorder=zorder)
    plt.fill_between(x, y, 0, color="lightgray", zorder=zorder)