python-gallery/gallery/user/themes/default/buttons/img-tool.scss

.tool-btn {
    margin: 0;
    padding: 0.5rem;

    width: 2.5rem;
    height: 2.5rem;

    border: none;
    background-color: transparent;
    color: $white100;

    svg {
        width: 1.25rem;
        height: 1.25rem;
    }

    &:hover {
        cursor: pointer;

        color: $green;
    }
}
.tool-btn--evil {
    color: $red;

    &:hover {
        color: $white100;
    }
}