:root {
  --bg: #f4f5f7;
  --surface: #ffffff;
  --text: #1d2330;
  --muted: #5f6878;
  --line: #dde1e7;
  --primary: #1d5fd1;
  --primary-text: #ffffff;
  --ok: #1d7a46;
  --ok-bg: #e6f4ec;
  --warn: #8a5a00;
  --warn-bg: #fff4dc;
  --err: #b42318;
  --err-bg: #fdecea;
  --radius: 10px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

[hidden] { display: none !important; }

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  background: var(--surface);
  border-bottom: 1px solid var(--line);
}
.brand { font-weight: 600; }
.user { display: flex; gap: 12px; align-items: center; color: var(--muted); font-size: 14px; }

main { max-width: 1000px; margin: 0 auto; padding: 24px 16px 48px; }

h1 { font-size: 26px; margin: 0 0 8px; }
h2 { font-size: 20px; margin: 0; }

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
}
.narrow { max-width: 480px; margin: 0 auto; }
.center { text-align: center; }
.muted { color: var(--muted); }
.small { font-size: 14px; }
.row { display: flex; align-items: center; gap: 12px; margin-bottom: 16px; flex-wrap: wrap; }
.spacer { flex: 1; }

.btn {
  font: inherit;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--text);
  padding: 8px 16px;
  border-radius: 8px;
  cursor: pointer;
}
.btn:disabled { opacity: .5; cursor: default; }
.btn.primary { background: var(--primary); border-color: var(--primary); color: var(--primary-text); }
.btn.ghost { background: transparent; }
.btn.big { padding: 12px 24px; font-size: 17px; margin-top: 16px; }
.link { background: none; border: 0; color: var(--primary); cursor: pointer; font: inherit; padding: 0; }

label { display: block; margin: 12px 0; font-weight: 500; }
label input { display: block; width: 100%; margin-top: 4px; padding: 8px 10px; font: inherit; border: 1px solid var(--line); border-radius: 8px; }

.banner { padding: 10px 14px; border-radius: 8px; margin: 12px 0; background: var(--warn-bg); color: var(--warn); }
.banner.error { background: var(--err-bg); color: var(--err); max-width: 1000px; margin: 12px auto 0; }
.banner.ok { background: var(--ok-bg); color: var(--ok); }
.banner.info { background: #e8f0fe; color: #123f8c; }

/* Testovací režim */
.god-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 12px;
  padding: 8px 16px;
  background: #5b21b6;
  color: #fff;
  font-size: 14px;
}
.god-bar .btn { padding: 4px 10px; font-size: 14px; }
.question label.god-correct { background: var(--ok-bg); border-radius: 6px; outline: 2px solid var(--ok); padding: 4px 6px; }
.question label.god-correct::after { content: "✓ správna"; color: var(--ok); font-weight: 600; white-space: nowrap; }

/* Prehľad krokov */
.steps { list-style: none; padding: 0; margin: 24px 0 0; }
.steps li {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  padding: 12px 0;
  border-top: 1px solid var(--line);
  color: var(--muted);
}
.steps li .icon {
  flex: none;
  width: 28px; height: 28px;
  border-radius: 50%;
  display: grid; place-items: center;
  border: 2px solid var(--line);
  font-size: 14px;
}
.steps li.done { color: var(--text); }
.steps li.done .icon { background: var(--ok); border-color: var(--ok); color: #fff; }
.steps li.current { color: var(--text); font-weight: 600; }
.steps li.current .icon { border-color: var(--primary); color: var(--primary); }
.steps .grow { flex: 1; }
.steps li .btn.small { flex: none; padding: 4px 12px; font-size: 14px; color: var(--primary); border-color: var(--primary); }
.steps .sub { display: block; font-weight: 400; font-size: 14px; color: var(--muted); }

/* Pravidlá pozerania */
.rules {
  display: flex;
  gap: 14px;
  align-items: center;
  margin: 0 0 16px;
  padding: 14px 18px;
  border: 2px solid #d97706;
  border-left-width: 8px;
  border-radius: var(--radius);
  background: #fff4dc;
  color: #7a3f00;
  font-size: 17px;
  line-height: 1.45;
}
.rules-icon {
  flex: none;
  width: 34px; height: 34px;
  border-radius: 50%;
  display: grid; place-items: center;
  background: #d97706;
  color: #fff;
  font-weight: 800;
  font-size: 20px;
}

.rules.review { border-color: var(--primary); background: #e8f0fe; color: #123f8c; }
.rules.review .rules-icon { background: var(--primary); }

/* Návod */
.howto { margin: 12px 0 0; border: 1px solid var(--line); border-radius: var(--radius); background: #f8f9fb; }
.howto summary { cursor: pointer; padding: 12px 16px; font-weight: 600; color: var(--primary); }
.howto[open] summary { border-bottom: 1px solid var(--line); }
#howto-body { padding: 4px 20px 12px; }
#howto-body h3 { font-size: 16px; margin: 14px 0 4px; }
#howto-body ul { margin: 0; padding-left: 20px; }
#howto-body li { margin: 4px 0; }

/* Prehrávač */
.player-box { background: #000; border-radius: var(--radius); overflow: hidden; }
.player-frame { position: relative; aspect-ratio: 16 / 9; }
#yt-host, #yt-host iframe { position: absolute; inset: 0; width: 100%; height: 100%; }
.shield { position: absolute; inset: 0; cursor: pointer; }
.controls { display: flex; align-items: center; gap: 12px; padding: 10px 12px; background: #15181e; color: #fff; flex-wrap: wrap; }
.controls .btn.ghost { color: #fff; border-color: #444; }
.bar { position: relative; flex: 1; min-width: 120px; height: 8px; background: #3a3f4a; border-radius: 4px; overflow: hidden; }
.bar-watched { position: absolute; inset: 0 auto 0 0; background: #6b7280; width: 0; }
.bar.seekable { cursor: pointer; height: 12px; }
.bar-current { position: absolute; inset: 0 auto 0 0; background: #4f8cff; width: 0; }
.time { font-variant-numeric: tabular-nums; font-size: 14px; }
#volume { width: 90px; }

.player-box:fullscreen { display: flex; flex-direction: column; border-radius: 0; }
.player-box:fullscreen .player-frame { flex: 1; aspect-ratio: auto; }

/* Test */
.quiz-head { margin-bottom: 16px; }
.question { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px 20px; margin: 0 0 12px; }
.question legend { font-weight: 600; padding: 0; float: left; width: 100%; margin-bottom: 8px; }
.question label { font-weight: 400; display: flex; gap: 10px; align-items: flex-start; margin: 6px 0; cursor: pointer; clear: both; }
.question input { display: inline-block; width: auto; flex: none; margin: 5px 0 0; padding: 0; }
.question label span { flex: 1; }

.score { font-size: 48px; font-weight: 700; margin: 8px 0; }
.score.ok { color: var(--ok); }
.score.bad { color: var(--err); }

/* Osvedčenie */
.cert-wrap { overflow-x: auto; }
.certificate {
  width: 100%;
  max-width: 960px;
  aspect-ratio: 297 / 210;
  margin: 0 auto;
  background: #fff;
  color: #1d2330;
  padding: 3%;
  container-type: inline-size;
  font-family: Georgia, "Times New Roman", serif;
}
.cert-inner {
  height: 100%;
  border: 0.9cqw double #8b6b2e;
  padding: 4cqw 6cqw;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  gap: 1cqw;
}
.cert-school { font-size: 1.9cqw; line-height: 1.4; white-space: pre-line; color: #5f6878; }
.cert-title { font-size: 6cqw; letter-spacing: .15em; color: #8b6b2e; margin-top: 1cqw; }
.cert-small { font-size: 1.8cqw; color: #5f6878; }
.cert-name { font-size: 4.2cqw; font-weight: 700; margin: 1cqw 0; border-bottom: 1px solid #c9b78f; padding: 0 3cqw .6cqw; }
.cert-course { font-size: 2.8cqw; font-style: italic; }
.cert-text { font-size: 2cqw; max-width: 80%; margin-top: 1.5cqw; }
.cert-foot { margin-top: auto; width: 100%; display: flex; justify-content: space-between; align-items: flex-end; font-size: 1.5cqw; text-align: left; }
.cert-foot .sign { border-top: 1px solid #1d2330; padding-top: .5cqw; width: 28%; text-align: center; color: #5f6878; }

@media (max-width: 600px) {
  .card { padding: 18px; }
  h1 { font-size: 22px; }
  #volume { display: none; }
}

@media print {
  @page { size: A4 landscape; margin: 0; }
  body { background: #fff; }
  .topbar, .no-print, #error, section:not(#view-cert) { display: none !important; }
  main { padding: 0; max-width: none; }
  .certificate { max-width: none; width: 297mm; height: 210mm; }
}