.app-layout{min-height:100vh;background:#f0f2f5}.app-header{background:#1890ff;text-align:center;position:sticky;top:0;z-index:1}.app-content{padding:24px;max-width:800px;margin:0 auto}.qr-preview-card{margin-top:16px}.qr-preview-card .ant-card-body{padding:24px}@media (max-width: 768px){.app-content{padding:16px}}*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,Noto Sans,sans-serif,"Apple Color Emoji","Segoe UI Emoji",Segoe UI Symbol,"Noto Color Emoji";-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}#root{min-height:100vh}