header{position:sticky;top:0;z-index:1}header nav{position:absolute;top:.5rem;left:.5rem;z-index:1}header nav a.btn:link,header nav a.btn:visited{box-shadow:0 0 .5rem .125rem #000;padding:.375rem .5rem}footer{position:static}main{max-width:60ch;margin-inline:auto}ul.toc{list-style:none;padding-left:1rem}aside.summary{padding-block:1rem;padding-left:1rem;border-left:2px solid #09ad7e;background-color:#097b5666;margin-bottom:1rem}aside.summary>:first-child:before{content:"In Short:";display:inline-block;font-weight:700}aside.summary>:last-child{margin-bottom:0}aside.metadata{font-variant:small-caps;font-weight:700;font-size:.8rem}ul{padding-left:2rem;margin-bottom:1rem}li{margin-bottom:.5rem}h2{margin-top:1.5rem}h3{font-size:1.25rem}