* { box-sizing: border-box; }
body {
  font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
  margin: 0;
  background: #0f1419;
  color: #e7ecf3;
  line-height: 1.5;
}
header {
  padding: 20px 24px;
  border-bottom: 1px solid #2a3544;
  background: #151b24;
}
header h1 { margin: 0; font-size: 1.25rem; }
header p { margin: 6px 0 0; color: #8b9cb3; font-size: 0.9rem; }
main { max-width: 880px; margin: 0 auto; padding: 24px; }
.card {
  background: #1a222d;
  border: 1px solid #2a3544;
  border-radius: 10px;
  padding: 16px 18px;
  margin-bottom: 12px;
}
.card h2 { margin: 0 0 6px; font-size: 1.05rem; }
.card .meta { color: #8b9cb3; font-size: 0.85rem; }
.card a { color: #5eb8ff; text-decoration: none; }
.card a:hover { text-decoration: underline; }
.empty { color: #8b9cb3; text-align: center; padding: 40px; }
pre.preview {
  background: #0d1117;
  border: 1px solid #2a3544;
  border-radius: 8px;
  padding: 12px;
  white-space: pre-wrap;
  word-break: break-word;
  font-size: 0.85rem;
  max-height: 280px;
  overflow: auto;
}
.hint {
  background: #1e2a3a;
  border-left: 3px solid #5eb8ff;
  padding: 12px 14px;
  border-radius: 0 8px 8px 0;
  font-size: 0.9rem;
  margin-top: 16px;
}
code { background: #0d1117; padding: 2px 6px; border-radius: 4px; }