:root{color:#222;font-family:system-ui,sans-serif}body{margin:0}.app{min-height:100vh;display:flex}.sidebar{background:#f4f4f4;width:220px;padding:1rem}.sidebar a{color:#222;padding:.4rem .6rem;text-decoration:none;display:block}.sidebar a.active{color:#fff;background:#1a4;border-radius:4px}.content{flex:1;padding:1.5rem}button{cursor:pointer;padding:.5rem .9rem}input,select{padding:.4rem}