:root {
  --oh-blue: #00558c;
  --oh-blue-dark: #003d66;
  --bg: #f4f6f9;
  --card: #ffffff;
  --line: #d8dee6;
  --text: #1f2a37;
  --muted: #5b6b7b;
  --good: #1f9d55;
  --warn: #c2410c;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
}
header {
  background: var(--oh-blue);
  color: #fff;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
header h1 { font-size: 18px; margin: 0; font-weight: 600; }
.header-right { display: flex; align-items: center; gap: 10px; }
.badge {
  background: rgba(255, 255, 255, 0.18);
  border-radius: 12px;
  padding: 3px 10px;
  font-size: 12px;
}
button {
  background: var(--oh-blue);
  color: #fff;
  border: 0;
  border-radius: 6px;
  padding: 9px 16px;
  font-size: 14px;
  cursor: pointer;
}
button:hover { background: var(--oh-blue-dark); }
header button { background: #fff; color: var(--oh-blue); }
.tabs {
  display: flex;
  gap: 4px;
  padding: 0 24px;
  background: var(--card);
  border-bottom: 1px solid var(--line);
}
.tabs button {
  background: transparent;
  color: var(--muted);
  border-bottom: 3px solid transparent;
  border-radius: 0;
  padding: 12px 16px;
}
.tabs button.active { color: var(--oh-blue); border-bottom-color: var(--oh-blue); font-weight: 600; }
main { max-width: 880px; margin: 24px auto; padding: 0 24px; }
.tab { display: none; }
.tab.active { display: block; }
.hint { color: var(--muted); font-size: 14px; line-height: 1.5; }
textarea, input[type="text"] {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 10px;
  font: inherit;
}
.fields {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin: 12px 0;
}
.fields label { font-size: 13px; color: var(--muted); display: flex; flex-direction: column; gap: 4px; }
.result {
  margin-top: 18px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 18px;
}
.hidden { display: none; }
.score-head { display: flex; align-items: baseline; gap: 12px; }
.score-num { font-size: 38px; font-weight: 700; color: var(--oh-blue); }
.score-band { font-size: 15px; font-weight: 600; }
.flags { margin: 10px 0; }
.flag { display: inline-block; font-size: 12px; padding: 3px 9px; border-radius: 12px; margin-right: 6px; }
.flag.warn { background: #fdecea; color: var(--warn); }
.flag.good { background: #e7f6ec; color: var(--good); }
.explain { color: var(--text); line-height: 1.5; margin: 10px 0; }
table { width: 100%; border-collapse: collapse; margin-top: 10px; font-size: 13px; }
th, td { text-align: left; padding: 6px 8px; border-bottom: 1px solid var(--line); }
th { color: var(--muted); font-weight: 600; }
.bar { background: #e6ebf1; border-radius: 4px; height: 8px; overflow: hidden; }
.bar > span { display: block; height: 100%; background: var(--oh-blue); }
.err { color: var(--warn); }