:root {
  --bg: #0f172a;
  --card: #ffffff;
  --text: #1e293b;
  --muted: #64748b;
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --border: #e2e8f0;
  --error: #dc2626;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}
.wrap { width: 100%; max-width: 640px; }
.card {
  background: var(--card);
  border-radius: 16px;
  padding: 32px;
  box-shadow: 0 20px 50px rgba(0,0,0,0.25);
}
.card.center { text-align: center; }
h1 { font-size: 1.5rem; margin: 0 0 12px; }
h2 { font-size: 1.2rem; margin: 16px 0; }
p { line-height: 1.5; color: var(--muted); }
.btn {
  appearance: none;
  border: 1px solid var(--border);
  background: #fff;
  color: var(--text);
  padding: 10px 18px;
  border-radius: 8px;
  font-size: 1rem;
  cursor: pointer;
  margin-right: 8px;
}
.btn.primary { background: var(--primary); border-color: var(--primary); color: #fff; }
.btn.primary:hover { background: var(--primary-dark); }
.btn:disabled { opacity: 0.6; cursor: not-allowed; }
.error { color: var(--error); }
.muted { color: var(--muted); font-size: 0.9rem; }
.progress { color: var(--muted); font-size: 0.9rem; margin-bottom: 4px; }
video {
  width: 100%;
  border-radius: 12px;
  background: #000;
  margin: 12px 0;
  max-height: 60vh;
}
.timer { color: var(--error); font-weight: 600; margin-bottom: 8px; }
.controls { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 8px; }
table { width: 100%; border-collapse: collapse; margin-top: 16px; }
th, td { text-align: left; padding: 8px 10px; border-bottom: 1px solid var(--border); font-size: 0.95rem; }
th { color: var(--muted); font-weight: 600; }
a { color: var(--primary); }
form.inline { display: inline; }
.badge { display: inline-block; padding: 2px 8px; border-radius: 999px; font-size: 0.8rem; }
.badge.pending { background: #f1f5f9; color: var(--muted); }
.badge.in_progress { background: #fef3c7; color: #92400e; }
.badge.completed { background: #dcfce7; color: #166534; }
input[type=text], input[type=email], input[type=password], textarea {
  width: 100%; padding: 8px 10px; border: 1px solid var(--border); border-radius: 8px; font-size: 1rem; margin-bottom: 12px;
}
label { font-weight: 600; font-size: 0.9rem; }
nav.admin-nav { margin-bottom: 20px; }
nav.admin-nav a { margin-right: 16px; }