如何在JS添加css类时应用css代码样式

Question

What's i'm trying to do is : i have a top fixed bar, that when scroll down it has a smaller height and the menu is ok, however the image logo scales under the black bar with about 5 px;

I thought to resolve this by: adding margin-top:30px to the logo, and i want when the class mk that changes the height of the bar to smaller one on scrolling, to make changes to the logo class to be margin-top:0 is this possible by JS?

Answer 1

In your logo maybe you can do something like?

element.style.marginTop="0px"

Basically what you want to do is that when you reach the logic of scrolling in your JavaScript code you want to do

var element = document.getElementId("IdOfYourElementThatyouWantToApply");

Then you apply the style like the code above.

Answer 2

你可以在javascript中执行此操作：

yourObject.style.marginTop="0px"

Answer 3

In JQuery you can do:

$('#YourId').attr('style', 'margin-top:0px');

If you want to have the older style, just do something like that:

    var style = $('#YourId').attr('style');
style += " margin-top:0px;"
    $('#YourId').attr('style', style);