coloring regions in a plot

I need help in this code:

I wrote this code but I want the output plot to be the same as what in the image below.

I have a difficulty in coloring these specific areas.

I will appreciate any help.

this is the code:

r=0.49;
s=2.94;
k=2.8;
m=0.22;
alpha=0.2;
beta=0.01;
h1=0.15;
h2=0.6;

axes1 = axes('Position',...
     [0.158854166666667,0.319833852544132,0.620833333333333,0.454595015576324]);
 hold(axes1,'on')
box(axes1,'on'); 
set(axes1,'ClippingStyle','rectangle','LineStyleOrder',{'-','-'},...
    'LineWidth',1.5);

l1=(m*s*beta)/(r*alpha);
l2=(m*(s-h2)*beta)/((r-h1)*alpha);
f3=@(a) ((-k*m*s-a*r*alpha+k*r*alpha+sqrt((a*r*alpha+k*(m*s-r*alpha))^2+4*k*r*alpha*(a*r*alpha-m*s*beta)))/(2*r*alpha));
f4=@(a)((h2*k*m-k*m*s-h1*k*alpha-a*r*alpha+k*r*alpha+sqrt((a*r*alpha+k*(m*(s-h2)+h1*alpha-r*alpha))^2+4*k*r*alpha*(a*(r-h1)*alpha-m*(s-h2)*beta)))/(2*r*alpha));
hold on
% plotting L1
plot([(m*s*beta)/(r*alpha),(m*s*beta)/(r*alpha)],[0,.02],'Color','k','LineWidth',1)
% plotting L2
plot([(m*(s-h2)*beta)/((r-h1)*alpha),(m*(s-h2)*beta)/((r-h1)*alpha)],[0,.02],'Color','k','LineWidth',1)
% plotting x0=xs0
fplot(f3,[0 3],'Color','k','LineWidth',1)
% plotting x0=xs1
fplot(f4,[0 3],'Color','k','LineWidth',1)
 xlim([0 .15])
 ylim([0 .01])
xticks([.04 .066 0.0789 0.14])
yticks([0 .005 .01])
xlabel('a')
ylabel('x0')

Answer 1

[Image Analyst]

Use patch or fill

[Doaa Mahmoud]

please,I am new to matlab

can you send me the code with the modification to color these particular sections.

I will appreciate your help