Dear roymustafa

1. Do you want to disable all the button use the class suffix: .button, button, .btReverse and only show the menu button on mobile?

-> please add the css:

.button, button, .btReverse {
background: #16a086;
color: #ffffff;
padding: 8px 20px;
display: inline-block;
vertical-align: top;
font-size: 14px;
border: none;
border-radius: 0px;
display: none;
}
#yt_mainmenu .btn-hamburger {
display: block;
}

2. about language: You should to clear your browser and check it again.
i checked it works normally.

Thanks