* { box-sizing: border-box; }
body { font-family: system-ui, sans-serif; max-width: 480px; margin: 40px auto; padding: 0 16px; }
h1 { font-size: 1.4rem; }
form { display: flex; flex-direction: column; gap: 16px; }
label { font-weight: 600; font-size: 0.9rem; }
input[type="file"] { font-size: 0.9rem; }
.checkbox-row { display: flex; align-items: center; gap: 8px; }
.checkbox-row label { font-weight: 400; }
button { padding: 10px 20px; font-size: 1rem; cursor: pointer; display: inline-flex; align-items: center; gap: 8px; justify-content: center; }
.spinner { width: 18px; height: 18px; border: 2px solid #ccc; border-top-color: #333; border-radius: 50%; animation: spin 0.6s linear infinite; display: inline-block; }
@keyframes spin { to { transform: rotate(360deg); } }