apply CSS style to particular elements dynamically

Question

I have a div with paragraphs inside:

  
...
  
...

I want dynamically to apply

Answer 1

With CSS you can define a child selector.

Building on that, you can dynamically add/remove a style class to your div and the style will apply to the children you specify in that selector.

Let's assume you want to apply this to a specific div, not any/every one. So give the target div an identifier:

  
...
  
...

Adding a dynamic style with simple javascript:

document.getElementById('foo').style.className='dynamic_style'

The CSS (using combined id and class on a child selector):

div#foo.dynamic_style > p { /* your style definition*/ }