:root {
  --blue: #1b4dff;
  --blue-dark: #143ad1;
  --text: #14203b;
  --muted: #5c6785;
  --bg: #f4f6fb;
  --card: #e8ecf6;
  --white: #ffffff;
  font-family: "Segoe UI", system-ui, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  min-height: 100%;
}

#app {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 16px 32px;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 0;
  position: sticky;
  top: 0;
  background: var(--bg);
  z-index: 2;
}

h1, h2 { margin: 0 0 8px; }
h1 { font-size: 1.25rem; }
h2 { font-size: 1.05rem; }

.screen { display: flex; flex-direction: column; gap: 16px; }
.hidden { display: none !important; }

.card {
  background: var(--white);
  border-radius: 16px;
  padding: 16px;
  box-shadow: 0 1px 2px rgba(20, 32, 59, 0.06);
}

.card.output { background: var(--card); white-space: pre-wrap; word-break: break-word; }

.muted { color: var(--muted); font-size: 0.85rem; margin: 4px 0 0; }

.btn {
  border: 0;
  border-radius: 12px;
  padding: 12px 16px;
  font-size: 1rem;
  cursor: pointer;
  width: 100%;
}

.btn:disabled { opacity: 0.45; cursor: not-allowed; }
.btn.primary { background: var(--blue); color: var(--white); }
.btn.primary:not(:disabled):hover { background: var(--blue-dark); }
.btn.tonal { background: #dbe4ff; color: var(--blue); }
.btn.outline { background: transparent; border: 1px solid #c5cde0; }

.row { display: flex; gap: 12px; }
.row .btn { flex: 1; }

.icon-btn {
  border: 0;
  background: transparent;
  font-size: 1.3rem;
  cursor: pointer;
}

.progress { display: flex; align-items: center; gap: 12px; }
.spinner {
  width: 18px;
  height: 18px;
  border: 2px solid #c5cde0;
  border-top-color: var(--blue);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin { to { transform: rotate(360deg); } }

dialog {
  border: 0;
  border-radius: 16px;
  padding: 20px;
  width: min(640px, 96vw);
  max-height: 90vh;
  overflow: auto;
}

dialog h3 {
  margin: 20px 0 8px;
  font-size: 1rem;
}

label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  margin-top: 12px;
}

.hint {
  color: var(--muted);
  font-size: 0.8rem;
  margin: 4px 0 0;
}

textarea {
  width: 100%;
  margin: 8px 0 0;
  padding: 10px;
  border-radius: 10px;
  border: 1px solid #c5cde0;
  font-size: 0.9rem;
  font-family: inherit;
  line-height: 1.4;
  resize: vertical;
}

dialog::backdrop { background: rgba(20, 32, 59, 0.4); }

input {
  width: 100%;
  padding: 12px;
  margin: 12px 0;
  border-radius: 10px;
  border: 1px solid #c5cde0;
  font-size: 1rem;
}

pre {
  max-height: 220px;
  overflow: auto;
  background: #0f172a;
  color: #e2e8f0;
  padding: 12px;
  border-radius: 8px;
  font-size: 11px;
}

#outputBody, #frozenBody { margin: 0; line-height: 1.45; }