While you edit a page or post (and provided a block is selected): it hides under the Advanced tab but once you click on the down arrow you can give a name to your class (e.g.: column-padding-0ytzj1-class)
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Pay attention to the dot in the “declaration” below. You don’t use this dot in the class assignment above.
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You then go to the Appearance > Customize > Additional CSS section in the WordPress dashboard and add the following CSS code to add, for example, padding to the block in the column:
.column-padding-0ytzj1-class {
padding: 20px;
}
to make an image borderless in Elementor using Custom CSS:
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Read more about CSS Selectors here