Cool-Y.github.io/themes/next/source/css/_common/components/third-party/gitment.styl

#gitment-display-button{
    display: inline-block;
    padding: 0 15px;
    color: #0a9caf;
    cursor: pointer;
    font-size: 14px;
    border: 1px solid #0a9caf;
    border-radius: 4px;
}
#gitment-display-button:hover{
    color: #fff;
    background: #0a9caf;
}