:root {
  --bg: #f4f5f7;
  --card: #ffffff;
  --ink: #1a1f2e;
  --muted: #6b7280;
  --primary: #0b3d91;
  --primary-ink: #ffffff;
  --border: #e5e7eb;
  --ok: #047857;
  --err: #b91c1c;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; background: var(--bg); color: var(--ink); font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif; }
body { padding: env(safe-area-inset-top) env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left); }

header { padding: 24px 20px 8px; }
header h1 { margin: 0; font-size: 24px; }
.muted { color: var(--muted); margin: 4px 0 0; font-size: 13px; }

main { padding: 12px 16px 24px; max-width: 600px; margin: 0 auto; }

.step { background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 16px; margin-bottom: 12px; }
.step h2 { margin: 0 0 12px; font-size: 16px; font-weight: 600; display: flex; align-items: center; gap: 10px; }
.num { display: inline-flex; width: 24px; height: 24px; border-radius: 50%; background: var(--primary); color: var(--primary-ink); align-items: center; justify-content: center; font-size: 13px; }

.file-drop { display: block; border: 2px dashed var(--border); border-radius: 10px; padding: 18px; text-align: center; cursor: pointer; color: var(--muted); }
.file-drop input { display: none; }
.file-drop.has-file { border-color: var(--primary); color: var(--ink); background: #f0f5ff; }

.file-list { list-style: none; padding: 0; margin: 12px 0 0; font-size: 14px; }
.file-list li { display: flex; justify-content: space-between; padding: 6px 0; border-bottom: 1px solid var(--border); }
.file-list li:last-child { border-bottom: 0; }
.file-list .size { color: var(--muted); font-size: 12px; }

.row { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
label { display: block; font-size: 13px; color: var(--muted); }
label input { width: 100%; margin-top: 4px; padding: 10px; font-size: 16px; border: 1px solid var(--border); border-radius: 8px; background: white; color: var(--ink); }

button.primary { width: 100%; padding: 14px; font-size: 16px; font-weight: 600; background: var(--primary); color: var(--primary-ink); border: 0; border-radius: 12px; margin-top: 4px; }
button.primary:disabled { opacity: 0.5; }

.status { margin-top: 16px; padding: 14px; border-radius: 10px; font-size: 14px; }
.status.info { background: #eff6ff; color: #1e3a8a; }
.status.ok { background: #ecfdf5; color: var(--ok); }
.status.err { background: #fef2f2; color: var(--err); white-space: pre-wrap; }
.hidden { display: none; }

footer { text-align: center; color: var(--muted); padding: 12px; font-size: 11px; }