why first name and last name doesn't fit to column bar like others??

Question

https://code.sololearn.com/WMyealpFRJmG

Answer 1

Try to reformat your HTML tags with proper indentation and you would be able to find it by spotting the difference. 😉

Answer 2

For the divs surrounding first name and last name you are using the bootstrap class col-md-6. These divs are child divs to a div that is using the bootstrap class col-md-4. You don't use a column inside a column. You can use another row inside a column and then a column inside that row, but you don't usually use a column directly inside another column or another row directly inside a row. Keep in mind that anything, in this version of bootstrap, that exceeds 12 columns in a row will overflow to the next row which can also lead to layout issues. For most of your formatting needs in the playground you'll probably want to use sm and xs for your media sizes.