:root {
  --fg: #1a1a1a;
  --bg: #fafafa;
  --border: #d8d8d8;
  --accent: #2b5fd9;
  --error: #b3261e;
}

* { box-sizing: border-box; }

body {
  font-family: -apple-system, "Hiragino Sans", "Yu Gothic", sans-serif;
  color: var(--fg);
  background: var(--bg);
  margin: 0;
  line-height: 1.6;
}

header {
  background: #fff;
  border-bottom: 1px solid var(--border);
  padding: 12px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

header h1 { font-size: 16px; margin: 0; }
header h1 a { color: var(--fg); text-decoration: none; }
nav a { margin-left: 16px; color: var(--accent); text-decoration: none; }

main {
  max-width: 900px;
  margin: 24px auto;
  padding: 0 20px 60px;
}

textarea {
  width: 100%;
  font-family: "SFMono-Regular", Menlo, Consolas, monospace;
  font-size: 13px;
  padding: 10px;
  border: 1px solid var(--border);
  border-radius: 6px;
}

label { display: block; margin-bottom: 6px; font-weight: 600; }

button {
  margin-top: 12px;
  padding: 10px 18px;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 6px;
  font-size: 14px;
  cursor: pointer;
}

button:disabled { opacity: 0.6; cursor: default; }

.hint { color: #555; font-size: 13px; }

.alert {
  background: #fdecea;
  color: var(--error);
  border: 1px solid #f5c2c0;
  padding: 10px 14px;
  border-radius: 6px;
  margin-bottom: 16px;
}

pre {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 14px;
  overflow-x: auto;
  font-size: 13px;
  white-space: pre-wrap;
  word-break: break-word;
}

pre.issues { background: #fffaf0; }

section { margin-bottom: 28px; }
section h2 { font-size: 15px; margin-bottom: 6px; }

.toolbar { margin-bottom: 8px; }
.toolbar button, .toolbar a {
  font-size: 12px;
  padding: 6px 10px;
  margin-right: 8px;
}
.toolbar a {
  display: inline-block;
  background: #eee;
  color: var(--fg);
  border-radius: 6px;
  text-decoration: none;
}

table { width: 100%; border-collapse: collapse; background: #fff; }
th, td { text-align: left; padding: 8px 10px; border-bottom: 1px solid var(--border); font-size: 13px; }
.error-badge { color: var(--error); font-weight: 600; }