html,body,#root{min-height:100%;margin:0}body{color:#1f2937;background:#f5f7fb;font-family:Inter,PingFang SC,Microsoft YaHei,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}.app-shell{box-sizing:border-box;min-height:100vh;padding:48px}.app-card{max-width:720px}