html[data-theme=default],html[data-theme=light],:root{--nav-bg:#f8f9fa}html[data-theme=dark]{--nav-bg:#333}html,body{margin:0;padding:0}body{display:flex;flex-direction:column;min-height:100vh}body #main-container{flex:1;justify-content:center;align-items:center;display:flex}