body{ font-family: Inter, Arial, sans-serif; padding: 20px; background:#f5f6fa; }
#app{ max-width:820px; margin: 0 auto; background:#fff; padding:20px; border-radius:8px; box-shadow: 0 2px 8px rgba(0,0,0,0.06); }
input, textarea{ width:100%; padding:8px; margin:6px 0; box-sizing:border-box; }
button{ padding:8px 12px; margin:4px; }
pre{ background:#111; color:#eee; padding:10px; border-radius:4px; }