To achieve your desired layout you will first have to change the way you have nested your content div
tags. First form pairs of associated div
tags that have year
and right
class. Nest these two div tags within a div
tag with class flex
. Below is an example of how this must be done.

Note that this needs to done for all the associated div
tags with year
and right
classes.
Next add the following css for the div
with flex
class. Also, correct the spelling of right
class in the relevant div
tag/s.
.flex {
display: flex;
flex-direction: row;
justify-content: center;
}
This will result in the following change in layout.

After this add padding-left: 50%;
to your .flex
class css. This gives you the desired result.
To finish off you can adjust the padding of the right
and year
classes.
Hope this helps you.