body { font-family: system-ui, sans-serif; margin: 0; background: #f6f7f9; color: #1a1a1a; }
main { max-width: 560px; margin: 12vh auto; padding: 0 16px; }
h1 { margin-bottom: 0; }
.tagline { color: #666; margin-top: 4px; }
form { display: flex; flex-direction: column; gap: 10px; }
.row { display: flex; gap: 10px; }
.row input { flex: 1; min-width: 0; }
input { padding: 10px; font-size: 16px; border: 1px solid #ccc; border-radius: 6px; }
button { padding: 10px; font-size: 16px; border: 0; border-radius: 6px; background: #2563eb; color: #fff; cursor: pointer; }
#result { font-size: 18px; word-break: break-all; }
.error { color: #b00020; }