/* ===================================================================
   QRGame — Stylesheet
   Glassmorphism · Dark theme · Mobile-first · Responsive
   =================================================================== */

:root {
  --bg-primary: #0f0c29;
  --bg-secondary: #1a1a2e;
  --glass-bg: rgba(255, 255, 255, 0.05);
  --glass-border: rgba(255, 255, 255, 0.12);
  --glass-blur: blur(16px);
  --text-primary: #f0f0f5;
  --text-secondary: #a0a0b8;
  --text-muted: #6a6a80;
  --accent: #4D96FF;
  --accent-2: #FF8E53;
  --success: #6BCB77;
  --danger: #FF6B6B;
  --warning: #FFD93D;
  --purple: #A55EEA;
  --radius-sm: 8px;
  --radius: 14px;
  --radius-lg: 20px;
  --radius-xl: 24px;
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.25);
  --shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.35);
  --font: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Inter', Roboto, sans-serif;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

*,*::before,*::after { box-sizing: border-box; margin: 0; padding: 0; }

html { font-size: 16px; -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--font);
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

body::before {
  content: '';
  position: fixed; inset: 0; z-index: 0; pointer-events: none;
  background:
    radial-gradient(ellipse 80% 60% at 20% 20%, rgba(77, 150, 255, 0.08) 0%, transparent 60%),
    radial-gradient(ellipse 60% 80% at 80% 70%, rgba(255, 142, 83, 0.06) 0%, transparent 60%),
    radial-gradient(ellipse 50% 50% at 50% 50%, rgba(107, 203, 119, 0.04) 0%, transparent 70%);
}

.container {
  position: relative; z-index: 1;
  max-width: 520px; margin: 0 auto; padding: 24px 16px 40px;
}

.container-wide {
  position: relative; z-index: 1;
  max-width: 1100px; margin: 0 auto; padding: 24px 16px 40px;
}

/* ── Header ─────────────────────────────────────────────── */

.header {
  text-align: center; padding: 24px 0 8px;
}

.title {
  font-size: clamp(1.8rem, 5vw, 2.4rem);
  font-weight: 800; letter-spacing: 0.04em;
  background: linear-gradient(135deg, #FFD93D 0%, #FF8E53 40%, #FF6B6B 70%, #A55EEA 100%);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 4px;
}

.subtitle {
  font-size: 0.95rem; color: var(--text-secondary);
  font-weight: 400; letter-spacing: 0.03em;
}

.nav-back {
  display: inline-flex; align-items: center; gap: 6px;
  color: var(--text-secondary); text-decoration: none;
  font-size: 0.85rem; margin-bottom: 8px; transition: color var(--transition);
}
.nav-back:hover { color: var(--text-primary); }

/* ── Cards / Glass Panel ────────────────────────────────── */

.glass {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur); -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
}

.card {
  padding: 24px; margin: 16px 0;
  text-align: center;
}

.card h2 {
  font-size: 1.3rem; font-weight: 700; margin-bottom: 6px;
}

.card p { color: var(--text-secondary); font-size: 0.88rem; }

/* ── Landing buttons ────────────────────────────────────── */

.landing-choices {
  display: flex; flex-direction: column; gap: 14px;
  margin: 32px 0;
}

.choice-btn {
  display: flex; align-items: center; gap: 14px;
  padding: 20px 24px;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  color: var(--text-primary);
  text-decoration: none;
  font-size: 1.05rem; font-weight: 600;
  transition: all var(--transition);
  backdrop-filter: var(--glass-blur); -webkit-backdrop-filter: var(--glass-blur);
}

.choice-btn:hover {
  background: rgba(255,255,255,0.1);
  border-color: rgba(255,255,255,0.25);
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.choice-btn .icon { font-size: 2rem; }

.choice-btn .label { flex: 1; }
.choice-btn .label small { display: block; font-weight: 400; font-size: 0.78rem; color: var(--text-muted); margin-top: 2px; }

/* ── Form ────────────────────────────────────────────────── */

.form-group { margin-bottom: 18px; text-align: left; }

.form-group label {
  display: block; font-size: 0.82rem; font-weight: 600;
  color: var(--text-secondary); margin-bottom: 6px;
  letter-spacing: 0.03em; text-transform: uppercase;
}

.form-group input {
  width: 100%; padding: 14px 16px;
  background: rgba(255,255,255,0.06);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-sm);
  color: var(--text-primary); font-size: 1rem;
  font-family: var(--font);
  transition: all var(--transition);
}

.form-group input::placeholder { color: var(--text-muted); }
.form-group input:focus {
  outline: none; border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(77, 150, 255, 0.2);
  background: rgba(255,255,255,0.08);
}

/* ── Buttons ─────────────────────────────────────────────── */

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  width: 100%; padding: 14px 24px;
  border: none; border-radius: var(--radius);
  font-size: 1rem; font-weight: 600; font-family: var(--font);
  cursor: pointer; transition: all var(--transition);
}
.btn:active { transform: scale(0.97); }

.btn-primary {
  background: linear-gradient(135deg, var(--accent), #6C5CE7);
  color: #fff;
  box-shadow: 0 4px 16px rgba(77, 150, 255, 0.3);
}
.btn-primary:hover {
  box-shadow: 0 6px 24px rgba(77, 150, 255, 0.45);
  transform: translateY(-1px);
}
.btn-primary:disabled { opacity: 0.5; cursor: not-allowed; transform: none; box-shadow: none; }

.btn-secondary {
  background: rgba(255,255,255,0.08); color: var(--text-primary);
  border: 1px solid var(--glass-border);
}
.btn-secondary:hover { background: rgba(255,255,255,0.14); }

.btn-danger {
  background: rgba(255,107,107,0.15); color: var(--danger);
  border: 1px solid rgba(255,107,107,0.25);
}
.btn-danger:hover { background: rgba(255,107,107,0.25); }

.btn-sm { width: auto; padding: 8px 16px; font-size: 0.8rem; border-radius: var(--radius-sm); }

/* ── QR display ──────────────────────────────────────────── */

.qr-wrapper {
  display: flex; flex-direction: column; align-items: center; gap: 12px;
  margin: 10px 0;
}

.qr-container {
  padding: 12px; background: #fff; border-radius: var(--radius);
  box-shadow: 0 4px 20px rgba(0,0,0,0.3); line-height: 0;
}
.qr-container canvas { display: block; }

.qr-hint {
  font-size: 0.72rem; color: var(--text-muted);
  letter-spacing: 0.03em;
}

.mission-box {
  padding: 16px; margin: 12px 0;
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: var(--radius);
  text-align: center;
}
.mission-box .mission-label {
  font-size: 0.7rem; text-transform: uppercase; letter-spacing: 0.08em;
  color: var(--text-muted); margin-bottom: 8px;
}
.mission-box .mission-text {
  font-size: 1rem; line-height: 1.6; color: var(--text-primary); font-weight: 500;
}

.student-info {
  text-align: center; margin: 8px 0;
  font-size: 0.9rem; color: var(--text-secondary);
}
.student-info strong { color: var(--text-primary); }

/* ── Teacher Dashboard ───────────────────────────────────── */

.dash-header {
  display: flex; align-items: center; justify-content: space-between;
  flex-wrap: wrap; gap: 12px;
  padding: 14px 20px; margin: 16px 0;
}

.stats-row {
  display: flex; gap: 20px; flex-wrap: wrap;
}
.stat-item { text-align: center; min-width: 60px; }
.stat-value { font-size: 1.5rem; font-weight: 700; }
.stat-label { font-size: 0.7rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--text-muted); }

.auto-refresh {
  font-size: 0.72rem; color: var(--text-muted);
  display: flex; align-items: center; gap: 4px;
}
.refresh-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--success); animation: pulse-dot 2s infinite; }

@keyframes pulse-dot {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.3; }
}

.student-table-wrap {
  overflow-x: auto; margin: 8px 0;
  border-radius: var(--radius-lg);
  border: 1px solid var(--glass-border);
}

.student-table {
  width: 100%; border-collapse: collapse;
  font-size: 0.9rem; min-width: 600px;
}

.student-table th {
  background: rgba(255,255,255,0.04);
  padding: 12px 14px; text-align: left;
  font-size: 0.72rem; text-transform: uppercase;
  letter-spacing: 0.06em; color: var(--text-muted);
  font-weight: 600; white-space: nowrap;
}

.student-table td {
  padding: 12px 14px;
  border-top: 1px solid rgba(255,255,255,0.06);
  vertical-align: middle;
}

.student-table tr:hover td {
  background: rgba(255,255,255,0.03);
}

.badge {
  display: inline-block; padding: 3px 10px; border-radius: 20px;
  font-size: 0.7rem; font-weight: 600;
}

.badge-success { background: rgba(107,203,119,0.15); color: var(--success); }
.badge-pending { background: rgba(255,142,83,0.15); color: var(--accent-2); }

.empty-state {
  text-align: center; padding: 48px 24px; color: var(--text-muted);
}
.empty-state .empty-icon { font-size: 3rem; margin-bottom: 12px; }
.empty-state p { font-size: 0.95rem; }

/* ── Toast ───────────────────────────────────────────────── */

.toast {
  position: fixed; bottom: 24px; left: 50%; transform: translateX(-50%);
  padding: 12px 24px; border-radius: var(--radius);
  font-size: 0.9rem; font-weight: 600; z-index: 999;
  animation: fadeInScale 0.3s ease;
  pointer-events: none;
}
.toast-success { background: var(--success); color: #000; }
.toast-error { background: var(--danger); color: #fff; }

/* ── Animations ──────────────────────────────────────────── */

@keyframes fadeInScale {
  from { opacity: 0; transform: translateX(-50%) scale(0.9) translateY(10px); }
  to   { opacity: 1; transform: translateX(-50%) scale(1) translateY(0); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}

/* ── Responsive ──────────────────────────────────────────── */

@media (max-width: 480px) {
  .container, .container-wide { padding: 12px 10px 24px; }
  .card { padding: 20px 16px; }
  .title { font-size: 1.4rem; }
  .student-table { font-size: 0.78rem; min-width: auto; }
  .student-table th, .student-table td { padding: 8px 8px; }
  .dash-header { padding: 12px 14px; }
  .stats-row { gap: 12px; }
  .stat-value { font-size: 1.2rem; }
}

/* ── Accessibility ───────────────────────────────────────── */

.btn:focus-visible, input:focus-visible, a:focus-visible {
  outline: 2px solid var(--accent); outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
  *,*::before,*::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}