biobulkbende.org/app/assets/scss/modules/_site-header.scss

.site-header{
	position: absolute;
	width: 100%;
	z-index: 2;
	transition: background-color .3s ease-out;
	
	@include atMedium(){
		position: fixed;
		background-color: rgba(#000, 0.4);
	}

	&__btn-container{
		@include atMedium(){
			float: right;
		}
	}

	&__menu-content{
		opacity: 0;
		transform: scale(1.2);
		transtion: all .3s ease-out;
		position: relative;
		z-index: -10;
		padding-top: 90px;
		text-align: center;

		@include atMedium(){
			opacity: 1;
			z-index: 1;
			padding-top: 0;
			transform: scale(1); 
		}
	}

	&__logo{
		position: absolute;
		top: 0;
		left: 50%;
		transform-origin: 50% 0%;
		transform: translateX(-50%) scale(.8);
		transition: transform .3s ease-out;

		@include atMedium(){
			position: relative;
			float: left;
			left: auto;
			transform: translateX(0);
		}
	}

}