:root {
  --bg: #f6f7f9;
  --card: #ffffff;
  --line: #d9dee7;
  --text: #0e1a2b;
  --muted: #50627a;
  --brand: #0b63f3;
  --brand-2: #0847ae;
  --danger: #b42318;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: radial-gradient(circle at 15% 20%, #e8f0ff 0, #f6f7f9 45%),
              radial-gradient(circle at 85% 10%, #fef3dc 0, #f6f7f9 40%);
  color: var(--text);
}
.app { max-width: 980px; margin: 24px auto; padding: 0 14px; display: grid; gap: 14px; }
.panel {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 16px;
  box-shadow: 0 8px 22px rgba(14, 26, 43, 0.06);
}
.hero h1 { margin: 0; font-size: 28px; }
.hero p { margin: 8px 0 0; color: var(--muted); }
h2 { margin: 0 0 12px; font-size: 18px; }
.grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
label { display: grid; gap: 6px; font-size: 14px; color: var(--muted); }
input {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 10px 12px;
  font-size: 14px;
  color: var(--text);
  background: #fff;
}
.actions { margin-top: 12px; display: flex; gap: 10px; flex-wrap: wrap; }
button {
  border: 0;
  border-radius: 10px;
  padding: 10px 14px;
  color: #fff;
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  cursor: pointer;
  font-weight: 600;
}
pre {
  margin: 12px 0 0;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 12px;
  background: #fbfcff;
  white-space: pre-wrap;
  word-break: break-word;
  max-height: 360px;
  overflow: auto;
}
.status:empty, .output:empty { display: none; }
.error { color: var(--danger); }
@media (max-width: 760px) {
  .grid { grid-template-columns: 1fr; }
}