That might be a specificity issue. When you apply CSS to something, and it doesnt take, the first thing to try is to add some more matching descriptors. That button is inside several divs each with their own class, and all tags in roll20 sheets are inside the .charsheet class. So in an extreme situation you can do this .charsheet div.sheet-colright div.sheet-characteristics div.sheet-2colrow div.sheet-colattribute button.sheet-button {
background-color: #ca352b;
border-radius: 8px;
border: 2px solid #c3a341;
text: center;
width: 100px;
height: 50px;
} Roll20 applies some styles to tags, and if their style is more specific (has more matching descriptors like the above) it will override any style you apply. To beat that, you have to apply more specific rules: the above rule, going from right to left, targets a button of class sheet-button, which is inside a div with class sheet-colattribute, which is inside another div with class sheet-2colrow, which is inside.... and so on up to .charsheet. If this is your issue, you wont need all these, you can delete some of them. For instance, this might work: .charsheet div.sheet-colright button.sheet-button {
or even .charsheet div button.sheet-button { That might be specific enough to override roll20's inbuilt styles, and also match any appropriate button on your sheet.