:root {
  --bg: #f6f4f0;
  --card: #ffffff;
  --ink: #1d1a16;
  --muted: #7a736a;
  --brand: #b4441f;
  --brand-ink: #ffffff;
  --ok: #1f7a3d;
  --fail: #b3261e;
  --line: #e4ded5;
  --radius: 14px;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.55;
}
.topbar {
  display: flex; align-items: center; justify-content: space-between;
  padding: 12px 20px; background: var(--card); border-bottom: 1px solid var(--line);
  position: sticky; top: 0; z-index: 10;
}
.brand { font-weight: 800; font-size: 18px; text-decoration: none; color: var(--ink); }
.brand span { color: var(--brand); }
.topnav { display: flex; align-items: center; gap: 16px; }
.topnav a { color: var(--ink); }
.username { color: var(--muted); }
.container { max-width: 860px; margin: 0 auto; padding: 24px 16px 60px; }
.footer { text-align: center; color: var(--muted); font-size: 13px; padding: 20px; }
h1 { font-size: 26px; margin: 8px 0 12px; }
h2 { font-size: 20px; }
a { color: var(--brand); }
.muted { color: var(--muted); }
.card {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 18px 20px; margin: 12px 0;
}
.card.narrow { max-width: 420px; margin: 48px auto; }
label { display: block; margin: 10px 0; font-weight: 600; }
input[type=text], input[type=password], textarea {
  width: 100%; padding: 10px 12px; margin-top: 4px;
  border: 1px solid var(--line); border-radius: 8px; font: inherit; background: #fdfcfa;
}
textarea { font-family: ui-monospace, Consolas, monospace; font-size: 13px; }
.btn {
  display: inline-block; padding: 9px 18px; border-radius: 10px;
  border: 1px solid var(--line); background: var(--card); color: var(--ink);
  font: inherit; font-weight: 600; text-decoration: none; cursor: pointer;
}
.btn.primary { background: var(--brand); color: var(--brand-ink); border-color: var(--brand); }
.btn.big { font-size: 18px; padding: 12px 28px; }
.btn.small { padding: 4px 10px; font-size: 13px; }
.linklike { background: none; border: none; color: var(--brand); cursor: pointer; font: inherit; padding: 0; }
.inline { display: inline; }
.alert { padding: 10px 14px; border-radius: 10px; }
.alert.error { background: #fdeceb; color: var(--fail); }
.alert.ok { background: #e8f5ec; color: var(--ok); }

.stage-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 14px; }
.card.stage { display: block; text-decoration: none; color: var(--ink); position: relative; }
.card.stage.open:hover { border-color: var(--brand); }
.card.stage.locked { opacity: 0.6; }
.card.stage.passed { border-color: var(--ok); }
.stage-num {
  width: 38px; height: 38px; border-radius: 50%; background: var(--brand); color: #fff;
  display: flex; align-items: center; justify-content: center; font-weight: 800; margin-bottom: 8px;
}
.stage.locked .stage-num { background: var(--muted); }
.stage.passed .stage-num { background: var(--ok); }
.status { font-weight: 600; }

.lesson-list li { margin: 8px 0; font-size: 17px; }
.lesson img { max-width: 100%; border-radius: 8px; }
.lesson table { border-collapse: collapse; width: 100%; margin: 12px 0; }
.lesson th, .lesson td { border: 1px solid var(--line); padding: 7px 10px; text-align: left; }
.lesson blockquote {
  margin: 12px 0; padding: 10px 16px; border-left: 4px solid var(--brand);
  background: #fbf7f2; border-radius: 0 8px 8px 0;
}
.lesson code { background: #f1ede6; padding: 1px 5px; border-radius: 4px; }
.pager { display: flex; justify-content: space-between; gap: 10px; margin: 18px 0; }

.exam-form .question legend { font-weight: 700; padding: 0 6px; }
.exam-form fieldset { border: 1px solid var(--line); }
.option { display: block; font-weight: 400; padding: 6px 8px; border-radius: 8px; cursor: pointer; }
.option:hover { background: #faf6f0; }
.result.ok { border-color: var(--ok); }
.result.fail { border-color: var(--fail); }
.score { font-size: 32px; font-weight: 800; margin: 4px 0; }
.review.ok { border-left: 4px solid var(--ok); }
.review.fail { border-left: 4px solid var(--fail); }

.table { border-collapse: collapse; width: 100%; }
.table th, .table td { border-bottom: 1px solid var(--line); padding: 7px 8px; text-align: left; font-size: 14px; }
.table tr.inactive { opacity: 0.5; }
.row-form { display: flex; gap: 8px; flex-wrap: wrap; }
.row-form input { width: auto; flex: 1; min-width: 130px; }
.actions form { margin-right: 6px; }

@media (max-width: 600px) {
  .container { padding: 14px 10px 40px; }
  .pager { flex-direction: column; }
  .table { display: block; overflow-x: auto; }
}