website/_src/assets/css/nav.css

body > nav::before,
body::after {
	z-index: -1;
	content: "";
	position: absolute;
	mask-image: url("/assets/img/theme/sundae_sit-lines.png");
	mask-repeat: no-repeat;
	margin: 0;
	width: inherit;
	height: inherit;
	pointer-events: none;
}

body > nav::before {
	bottom: 0;
	left: 0;
	mask-size: 150%;
	-webkit-mask-position-x: -10px;
	-webkit-mask-position-y: 90%;
}

body::after {
	content: none;
	mask-size: 100%;
	width: 100%;
	height: 100vw;
	-webkit-mask-position-x: 0;
	-webkit-mask-position-y: bottom;
}

body {
	font-family: "Rubik", sans-serif;
	& > nav {
		gap: var(--pad-m);
		& details {
			gap: inherit;
			border-radius: var(--round);
			font-weight: bold;
		}
		& details > summary {
			display: flex;
			align-items: center;
			justify-content: center;
			padding: 0 var(--pad-lm) 0 0;
			height: var(--pad-xl);

			& > svg {
				transform: rotate(0deg);
				transition: transform var(--trans);
			}
		}
		& details:not([open]) > summary {
			border-radius: var(--round);
			border-style: solid;
			border-width: 2px;
		}

		& details[open] {
			border-style: solid;
			border-width: 2px;
			& > summary {
				margin-bottom: var(--pad-sm);
				& svg {
					transform: rotate(45deg);
				}
			}

			& a {
				border-style: solid;
				border-width: 2px;
				margin: 0 var(--pad-sm);
				margin-bottom: var(--pad-sm);
				border-radius: var(--round);
			}
		}
	}
}