Note: After publishing, you may have to bypass your browser's cache to see the changes.

• Firefox / Safari: Hold Shift while clicking Reload, or press either Ctrl-F5 or Ctrl-R (⌘-R on a Mac)
• Google Chrome: Press Ctrl-Shift-R (⌘-Shift-R on a Mac)
• Edge: Hold Ctrl while clicking Refresh, or press Ctrl-F5.

/*активная кнопка*/
.sy {
    padding: 3px;
        background: transparent;
    border: 3px solid transparent;
        width: 64px;
    height: 64px;
}
/*обычная кнопка*/
.sn {
    padding: 3px;
    border: 3px solid transparent;
        width: 64px;
    height: 64px;
    background: transparent;
}