Take a look around line 1085 in your css and change the size like this –
.entry-title {
font-size: 28px;
font-weight: 400;
line-height: 1.3;
padding: 0 20px;
}
You’ll see some code that looks like this – font-size: 2.25rem;
…..you can remove that if you would rather just use the px instead.
The above suggestion should work for both titles on each of those pages.