body { font-family: system-ui, sans-serif; margin: 0; padding: 16px; max-width: 32rem; }
h1 { font-size: 1.4rem; }
h2 { font-size: 1.1rem; margin-top: 1.5rem; }
button, input { font-size: 1rem; padding: 10px 12px; }
input { width: 100%; box-sizing: border-box; }
pre { white-space: pre-wrap; background: #f1f5f9; padding: 8px; }