Mobile menu disappeared

The “.screen-reader-text” style in jetpack.css overwrites the rules of the template
Why? How can it be avoided?

.screen-reader-text {
	border: 0;
	clip: rect(1px,1px,1px,1px);
	-webkit-clip-path: inset(50%);
	clip-path: inset(50%);
	height: 1px;
	margin: -1px;
	overflow: hidden;
	padding: 0;
	position: absolute !important;
	width: 1px;
	word-wrap: normal !important;
}

https://github.com/justintadlock/stargazer/issues/64