How to distinguish several <div>

Hello,
I am building the site https://www.scaiecat-spa-gigi.com
On the page
https://www.scaiecat-spa-gigi.com/sv/faktaomitalien.php
I have tried to write much information about Italy.
I often update this page.
In order to distinguish several paragraphs I have also created different
<div>
Each of these has been distinguished through a "class" and and an "id"
I guess that I should define these classes and ids on my external style
sheet. But I wonder how I could distinguish them visually.
Would it be good to use different background colours? If I do that, the text
would get less readable.
Any suggestions?
I have also tried to create an index (under construction)
The same works
for https://www.scaiecat-spa-gigi.com/it/svezia.html

--
Luigi Donatello Asero
https://www.scaiecat-spa-gigi.com/sv/faktaomitalien.php
今天二零零六年五月二日
星期二

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