:root{color-scheme:light}body{margin:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif;color:#1c1c1c;background:#f7f8fa;line-height:1.5}.app-main{max-width:720px;margin:0 auto;padding:1rem}.app-header{display:flex;justify-content:flex-end;padding:.5rem 1rem;background:#fff;border-bottom:1px solid #e5e7eb}.visually-hidden{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}