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Why the margin of ".gallery li" is 2.5% instead of 5%? PLEASE,

According to my understanding,

Gallery is divided to 45% out of 100%. THere are 2 colomns which mean 45% * 2 = 90%

remaining 100% - 90% = " 10% " (Total margin)

10% of total margin is divided by 2 = " 5% " for each margin.

My wonder is why we choose 2.5% as margin for ".gallery li"?

Hi hoppy,

If each column is 45% wide and you have 2, you have 90% of the full width.

when you set the margin of an element like this margin: 2.5% what happens is a a margin around the element of 2.5%

```          |
```

[ -- element --] |

so the element has: margin-left: 2.5%, margin-right: 2.5% margin-top:2.5%, margin-bottom:2.5%

If you add margin-left and margin-right you get the 5% you are looking for.

thank you, Hugo. I appreciate that.