Why is this code not working?

Hi there, I would like minimize the codes my posts, so I would like to set all everything in the general settings.
But now I’ve noticed that the background color for my buttons is not working when I set this in the general CSS settings.
The background color code does work when I add it to the button inside the post, but I want to prevent this.

To make sure I have every CSS code, this is what I’ve created:

.su-button {margin-top: 2px; margin-bottom: 2px; background-color: #8B714E;}
.su-button-style-default { background-color:#8B714E; padding: 0px;}
.su-button-style-default span { padding: 15px; background-color: #8B714E;}
.su-button-style-soft:hover span {background: #EFE1CB; }

And this is in my post, which is only working when I put the color code there.

[su_button background=”#8B714E” etc….

What am I doing wrong?

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