How could I get the color of the surface to normal yellow for this surface plot?

I am plotting a yellow surface using Python with color='yellow', here is the codes that I wrote:

import matplotlib.pyplot as plt
import numpy as np
import math
from mpl_toolkits import mplot3d

#Below is the actual plot:
#============================================================================
fig = plt.figure(figsize=(20,10))
ax = fig.add_subplot(1,1,1, projection='3d')
x = np.arange(0,10)
y = np.arange(0,10)
X,Y = np.meshgrid(x,y)
Z = -X**2-Y**2
ax.plot_surface(X, Y, Z,  color='yellow', alpha=.5)

However, what I obtained is a yellow surface looks like this: enter image description here,

which does not look very yellow.

The yellow color that I am intended to get for the surface should look like this: enter image description here, which could be easily obtained in 2d plots. However, it seems to me that I am unable to obtain this color in 3d surface plots.

Is there any way that I could obtain the normal yellow in the 3d plots? Many thanks in advance for any help and advice!

Solution

import matplotlib.pyplot as plt
import numpy as np
import math
from mpl_toolkits import mplot3d

#Below is the actual plot:
#============================================================================
fig = plt.figure(figsize=(20,10))
ax = fig.add_subplot(1,1,1, projection='3d')
x = np.arange(0,10,)
y = np.arange(0,10,)
X,Y = np.meshgrid(x,y)
Z = -X**2-Y**2
ax.plot_surface(X,Y,Z,color='yellow', shade=False)

you can use shade=False and you will get a nice yellow color. Hope that helps