<div class="header__burger">
<span></span>
</div>
.header__burger {
position: relative;
width: 30px;
height: 30px;
}
.header__burger span::before {
content: "";
width: 30px;
height: 2px;
background: #000;
position: absolute;
left: 0;
top: 10px;
}
.header__burger span::after {
content: "";
width: 30px;
height: 2px;
background: #000;
position: absolute;
left: 0;
top: -10px;
}
.header__burger span {
width: 30px;
height: 2px;
background: #000;
position: absolute;
left: 0;
top: 50%;
}