:root {
  --bg:#f5f7fa;
  --card:#fff;
  --radius:10px;
  --shadow:0 10px 25px -10px rgba(0,0,0,0.06);
  --border:#e3e8ef;
  --accent:#2563eb;
  font-family: "Segoe UI", -apple-system, system-ui, "Helvetica Neue", Arial, sans-serif;
}

* {box-sizing:border-box;}

body {
  margin:0;
  background: var(--bg);
  color:#1f2d3d;
  line-height:1.4;
  font-size:14px;
}

h1, h2, h3 {margin:0;}
.meta {
  font-size: .85rem;
  color: #556674;
  margin-top:2px;
}

.card-tool {
  background: #fff;
  border-radius: var(--radius);
  padding: 14px 16px 18px;
  box-shadow: var(--shadow);
  border: 1px solid #f0f4fa;
  margin-bottom: 8px;
}

textarea {
  width:100%;
  min-height:180px;
  resize: vertical;
  padding:12px;
  font-family: "Source Code Pro", Consolas, monospace;
  font-size:13px;
  border:1px solid var(--border);
  border-radius:6px;
  background:#fdfdfd;
  line-height:1.3;
  margin-top:6px;
}

.btn-primary {
  background: var(--accent);
  border: none;
  font-weight:600;
  border-radius:6px;
  padding:8px 16px;
}

.small-tag {
  background:#eef5ff;
  border-radius:4px;
  padding:4px 10px;
  font-size:.65rem;
  display:inline-block;
}

@media (max-width: 768px) {
  .card-tool {padding:12px;}
  textarea {min-height:150px;}
}