:root{--pad:18px;font-family:system-ui,Arial,Helvetica,sans-serif} body{padding:var(--pad);max-width:820px;margin:0 auto;color:#111} h1{margin-top:0} label{display:block;margin:10px 0} input{padding:8px;width:100%;max-width:260px} .controls{margin-top:10px} button{padding:8px 12px;margin-right:8px} .out{background:#f7f7f7;padding:12px;border-radius:6px} nav ul{list-style:none;padding:0} nav li{display:inline;margin-right:12px} .notes{font-size:0.9rem;color:#444} footer{margin-top:30px;border-top:1px solid #eee;padding-top:12px} a{color:#0366d6;text-decoration:none}