:root {
  --bg: #f6f7fb;
  --card: #ffffff;
  --ink: #1a1d29;
  --muted: #6b7280;
  --line: #e6e8ef;
  --primary: #4f46e5;
  --primary-ink: #ffffff;
  --accent: #0ea5a4;
  --result-bg: #eef2ff;
  --result-ink: #312e81;
  --error: #dc2626;
  --radius: 14px;
  --shadow: 0 1px 2px rgba(16,24,40,.06), 0 8px 24px rgba(16,24,40,.06);
  --tap: 44px;
}

* { box-sizing: border-box; }

html, body { margin: 0; }

body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.wrap {
  max-width: 680px;
  margin: 0 auto;
  padding: 28px 20px 56px;
}

.top { margin-bottom: 18px; }
h1 {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -.01em;
  margin: 0 0 6px;
}
.lede {
  margin: 0;
  color: var(--muted);
  font-size: .98rem;
}

.tool {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 18px;
}

.field-label {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  font-weight: 600;
  font-size: .95rem;
  margin-bottom: 8px;
}
.count { font-weight: 500; color: var(--muted); font-size: .82rem; }

.names {
  width: 100%;
  min-height: 168px;
  resize: vertical;
  padding: 12px 14px;
  font: inherit;
  font-size: 1rem;
  color: var(--ink);
  background: #fbfbfe;
  border: 1px solid var(--line);
  border-radius: 10px;
  outline: none;
  transition: border-color .15s ease, box-shadow .15s ease;
}
.names:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(79,70,229,.15);
}

.row { display: flex; gap: 10px; margin-top: 14px; }

.btn {
  min-height: var(--tap);
  padding: 0 18px;
  font: inherit;
  font-weight: 600;
  font-size: 1rem;
  border-radius: 10px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform .08s ease, background .15s ease, border-color .15s ease;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--primary); color: var(--primary-ink); }
.btn-primary:hover { background: #4338ca; }
.btn-ghost { background: transparent; color: var(--muted); border-color: var(--line); }
.btn-ghost:hover { color: var(--ink); border-color: #d3d7e3; }

.opt {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 12px;
  font-size: .92rem;
  color: var(--muted);
  cursor: pointer;
}
.opt input { width: 18px; height: 18px; accent-color: var(--primary); }

.error {
  margin: 12px 0 0;
  color: var(--error);
  font-size: .9rem;
  font-weight: 500;
}

.result {
  margin-top: 16px;
  padding: 18px;
  background: var(--result-bg);
  border: 1px solid #dfe3fb;
  border-radius: 12px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  animation: pop .18s ease;
}
.result-label {
  font-size: .78rem;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--accent);
  font-weight: 700;
}
.result-body {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  flex-wrap: wrap;
}
.picked {
  flex: 1 1 auto;
  min-width: 0;
  font-size: clamp(1.8rem, 7vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -.02em;
  color: var(--result-ink);
  line-height: 1.1;
  word-break: break-word;
  overflow-wrap: anywhere;
}
.btn-copy {
  flex: 0 0 auto;
  background: #ffffff;
  color: var(--primary);
  border: 1px solid #c7cbf3;
}
.btn-copy:hover { background: #f5f6ff; }
.btn-copy.copied { color: var(--accent); border-color: var(--accent); }

@keyframes pop {
  from { opacity: 0; transform: translateY(4px) scale(.99); }
  to   { opacity: 1; transform: none; }
}

.info {
  margin-top: 30px;
  color: #374151;
}
.info h2 {
  font-size: 1.12rem;
  font-weight: 700;
  margin: 22px 0 8px;
}
.info p, .info li, .info dd { font-size: .96rem; }
.info code {
  background: #eef0f6;
  padding: 1px 6px;
  border-radius: 6px;
  font-size: .9em;
}
.info dl { margin: 0; }
.info dt { font-weight: 700; margin-top: 12px; }
.info dd { margin: 4px 0 0; color: var(--muted); }

.foot {
  margin-top: 36px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: .85rem;
}

@media (max-width: 480px) {
  .wrap { padding: 18px 14px 44px; }
  h1 { font-size: 1.3rem; }
  .tool { padding: 14px; }
  .names { min-height: 150px; }
  .row { flex-direction: column; }
  .btn { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  *, .result { animation: none !important; transition: none !important; }
}