.App{min-height:100vh;display:flex;flex-direction:column}header{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;padding:2rem;text-align:center}header h1{margin:0 0 .5rem;font-size:2rem}header p{margin:0;opacity:.9}main{flex:1;padding:1rem;background:#f5f5f5}*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}code{font-family:source-code-pro,Menlo,Monaco,Consolas,Courier New,monospace}