There is a sass code
%btn{ font-size:12px; background:#cecece; } .header_btn{ @extend %btn; width:100px; } it is converted to such waters css
.header_btn { font-size: 12px; background: #cecece; } .header_btn { width: 100px; } How to make it so that there is only one selector in which all these properties will be located, because if you leave it so much fuck up (