:root {
  --primary: #6366f1;
  --primary-dark: #4f46e5;
  --primary-light: #eef2ff;
  --primary-glow: rgba(99, 102, 241, 0.25);
  --success: #10b981;
  --success-dark: #059669;
  --success-light: #d1fae5;
  --danger: #ef4444;
  --danger-dark: #dc2626;
  --danger-light: #fee2e2;
  --warning: #f59e0b;
  --warning-light: #fef3c7;
  --bg: #f1f5f9;
  --surface: #ffffff;
  --text: #0f172a;
  --text-soft: #334155;
  --muted: #64748b;
  --border: #e2e8f0;
  --border-soft: #f1f5f9;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.07), 0 2px 4px -2px rgb(0 0 0 / 0.05);
  --shadow-lg: 0 10px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.05);
  --radius-sm: 8px;
  --radius: 12px;
  --radius-lg: 16px;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background:
    radial-gradient(circle at 0% 0%, rgba(99, 102, 241, 0.08), transparent 40%),
    radial-gradient(circle at 100% 0%, rgba(168, 85, 247, 0.06), transparent 40%),
    var(--bg);
  background-attachment: fixed;
  color: var(--text);
  line-height: 1.6;
  font-size: 15px;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 1040px;
  margin: 0 auto;
  padding: 28px 24px;
}

/* ===== TOPBAR ===== */
.topbar {
  background: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
  color: #fff;
  padding: 14px 0;
  box-shadow: 0 2px 8px rgba(79, 70, 229, 0.2);
  position: sticky;
  top: 0;
  z-index: 50;
}
.topbar .container { padding: 0 24px; }
.topbar-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 44px;
  gap: 16px;
}
.topnav { display: flex; gap: 4px; margin-left: auto; margin-right: 12px; }
.topnav a {
  color: rgba(255, 255, 255, 0.85);
  text-decoration: none;
  padding: 6px 14px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  transition: background 0.15s ease, color 0.15s ease;
}
.topnav a:hover { background: rgba(255, 255, 255, 0.12); color: #fff; }
.brand {
  color: #fff;
  font-weight: 700;
  text-decoration: none;
  font-size: 18px;
  letter-spacing: -0.01em;
  display: flex;
  align-items: center;
  gap: 8px;
}
.brand::before {
  content: "";
  display: inline-block;
  width: 22px;
  height: 22px;
  border-radius: 6px;
  background: linear-gradient(135deg, #fbbf24, #f97316);
  box-shadow: 0 2px 8px rgba(251, 191, 36, 0.4);
}

/* ===== TYPOGRAPHY ===== */
h1 {
  margin: 0 0 8px;
  font-size: 28px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
}
h2 {
  margin: 0 0 14px;
  font-size: 19px;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--text);
}
.muted { color: var(--muted); }
.small { font-size: 13px; }

.alert {
  color: var(--danger-dark);
  background: var(--danger-light);
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--danger);
  margin: 0 0 12px;
  font-size: 14px;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  color: var(--primary);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 14px;
  transition: gap 0.15s ease;
}
.back-link:hover { gap: 8px; }

/* ===== CARD ===== */
.card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  padding: 26px;
  margin-bottom: 18px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border-soft);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}
.card.centered { text-align: center; }
.card.centered .form-stack { text-align: left; }

/* ===== BUTTONS ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 9px 16px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text-soft);
  cursor: pointer;
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  font-family: inherit;
  transition: all 0.15s ease;
  line-height: 1.2;
}
.btn:hover {
  background: var(--border-soft);
  border-color: #cbd5e1;
  transform: translateY(-1px);
}
.btn:active { transform: translateY(0); }

.btn-primary {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: #fff;
  border-color: transparent;
  box-shadow: 0 4px 12px var(--primary-glow);
}
.btn-primary:hover {
  background: linear-gradient(135deg, var(--primary-dark) 0%, #4338ca 100%);
  border-color: transparent;
  box-shadow: 0 6px 16px var(--primary-glow);
}

.btn-danger {
  background: var(--surface);
  color: var(--danger-dark);
  border-color: var(--danger-light);
}
.btn-danger:hover {
  background: var(--danger-light);
  border-color: #fca5a5;
}

.btn-large { padding: 14px 28px; font-size: 16px; font-weight: 600; }
.btn-small { padding: 5px 10px; font-size: 12px; }

.btn-logout {
  background: rgba(255, 255, 255, 0.12);
  color: #fff;
  border-color: rgba(255, 255, 255, 0.2);
  backdrop-filter: blur(8px);
}
.btn-logout:hover {
  background: rgba(255, 255, 255, 0.2);
  border-color: rgba(255, 255, 255, 0.3);
}

/* ===== FORMS ===== */
.form-inline {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-top: 14px;
}
.form-inline input { flex: 1; min-width: 180px; }

.form-stack {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-top: 14px;
}
.form-stack label {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-soft);
  letter-spacing: 0.01em;
  text-transform: uppercase;
}

input[type="text"], input[type="password"], textarea {
  width: 100%;
  padding: 11px 14px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-family: inherit;
  background: var(--surface);
  color: var(--text);
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
  font-weight: 400;
  text-transform: none;
  letter-spacing: normal;
}
input[type="text"]:focus, input[type="password"]:focus, textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px var(--primary-glow);
}
input[type="text"]::placeholder, textarea::placeholder {
  color: #94a3b8;
  font-weight: 400;
}

.choice-row {
  display: flex !important;
  flex-direction: row !important;
  align-items: center;
  gap: 12px;
  text-transform: none !important;
  font-size: 14px !important;
  font-weight: 400 !important;
  background: var(--border-soft);
  padding: 8px 12px;
  border-radius: var(--radius-sm);
}
.choice-row input[type="radio"] {
  margin: 0;
  width: 18px;
  height: 18px;
  accent-color: var(--primary);
  flex-shrink: 0;
}
.choice-row input[type="text"] {
  border: 1px solid transparent;
  background: transparent;
  padding: 6px 8px;
}
.choice-row input[type="text"]:focus {
  background: var(--surface);
  border-color: var(--primary);
}

/* ===== TABLE ===== */
.table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 4px;
  font-size: 14px;
}
.table th, .table td {
  text-align: left;
  padding: 12px 12px;
  border-bottom: 1px solid var(--border-soft);
  vertical-align: middle;
}
.table tr:last-child td { border-bottom: none; }
.table th {
  font-size: 12px;
  font-weight: 600;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background: var(--border-soft);
}
.table tbody tr { transition: background 0.12s ease; }
.table tbody tr:hover { background: var(--primary-light); }

.actions { display: flex; gap: 6px; flex-wrap: wrap; }

/* ===== URL ===== */
.url {
  display: inline-block;
  background: var(--primary-light);
  color: var(--primary-dark);
  padding: 5px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 500;
  font-family: ui-monospace, "SF Mono", Menlo, monospace;
  word-break: break-all;
}
.url-box {
  margin-top: 16px;
  padding: 16px;
  background: linear-gradient(135deg, var(--primary-light) 0%, #f5f3ff 100%);
  border-radius: var(--radius);
  border: 1px solid rgba(99, 102, 241, 0.15);
}
.url-row {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: 6px;
}

/* ===== QUESTIONS ===== */
.question-list { list-style: none; padding: 0; margin: 0; }
.question-item {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 20px;
  margin-bottom: 14px;
  background: var(--surface);
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}
.question-item:hover { border-color: #cbd5e1; box-shadow: var(--shadow-sm); }
.q-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
  font-size: 12px;
  font-weight: 600;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.q-text {
  margin: 6px 0 14px;
  font-size: 16px;
  font-weight: 500;
  color: var(--text);
  line-height: 1.5;
}

.choice-list { list-style: none; padding-left: 0; margin: 0; }
.choice-list li {
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  margin-bottom: 6px;
  background: var(--border-soft);
  font-size: 14px;
  border: 1px solid transparent;
  transition: all 0.15s ease;
}
.choice-list li.correct {
  background: var(--success-light);
  color: var(--success-dark);
  border-color: rgba(16, 185, 129, 0.25);
  font-weight: 500;
}
.choice-list li.wrong {
  background: var(--danger-light);
  color: var(--danger-dark);
  border-color: rgba(239, 68, 68, 0.25);
  font-weight: 500;
}

.choice-list-form {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: 12px;
}
.choice-option {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 16px;
  background: var(--surface);
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.15s ease;
  font-size: 15px;
}
.choice-option:hover {
  background: var(--primary-light);
  border-color: var(--primary);
  transform: translateX(2px);
}
.choice-option input[type="radio"] {
  margin: 0;
  width: 20px;
  height: 20px;
  accent-color: var(--primary);
  flex-shrink: 0;
}
.choice-option:has(input[type="radio"]:checked) {
  background: var(--primary-light);
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

/* ===== BADGES ===== */
.badge {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--success-light);
  color: var(--success-dark);
  font-size: 11px;
  font-weight: 600;
  margin-left: 6px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}
.badge-correct { background: var(--success-light); color: var(--success-dark); }
.badge-wrong { background: var(--danger-light); color: var(--danger-dark); }

/* ===== SCORE / STATS ===== */
.score {
  margin: 24px 0;
  padding: 24px;
  background: linear-gradient(135deg, var(--primary-light) 0%, #f5f3ff 100%);
  border-radius: var(--radius-lg);
  border: 1px solid rgba(99, 102, 241, 0.15);
}
.score-num {
  font-size: 56px;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  letter-spacing: -0.04em;
  line-height: 1;
}

.stat-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 12px;
  margin-top: 16px;
}
.stat {
  background: var(--border-soft);
  border-radius: var(--radius);
  padding: 18px 16px;
  text-align: center;
  border: 1px solid transparent;
  transition: transform 0.15s ease;
}
.stat:hover { transform: translateY(-2px); }
.stat .stat-num {
  font-size: 32px;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.02em;
  line-height: 1.2;
}
.stat > div:last-child {
  font-size: 12px;
  color: var(--muted);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-top: 4px;
}
.stat.correct {
  background: var(--success-light);
  border-color: rgba(16, 185, 129, 0.2);
}
.stat.correct .stat-num { color: var(--success-dark); }
.stat.wrong {
  background: var(--danger-light);
  border-color: rgba(239, 68, 68, 0.2);
}
.stat.wrong .stat-num { color: var(--danger-dark); }

/* ===== PROGRESS BAR ===== */
.bar {
  display: flex;
  margin-top: 16px;
  border-radius: 999px;
  overflow: hidden;
  height: 36px;
  font-size: 12px;
  color: #fff;
  font-weight: 600;
  box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.06);
  background: var(--border-soft);
}
.bar-correct {
  background: linear-gradient(90deg, var(--success), var(--success-dark));
  display: flex;
  align-items: center;
  justify-content: center;
  transition: width 0.4s ease;
  letter-spacing: 0.02em;
}
.bar-wrong {
  background: linear-gradient(90deg, #f87171, var(--danger));
  display: flex;
  align-items: center;
  justify-content: center;
  transition: width 0.4s ease;
  letter-spacing: 0.02em;
}

.text-correct { color: var(--success-dark); font-weight: 600; }
.text-wrong { color: var(--danger-dark); font-weight: 600; }

/* ===== LEADERBOARD ===== */
.leaderboard-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}
.live-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  border-radius: 999px;
  background: var(--danger-light);
  color: var(--danger-dark);
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
.live-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--danger);
  animation: lb-pulse 1.5s ease-in-out infinite;
}
@keyframes lb-pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.4; transform: scale(0.85); }
}

.leaderboard { list-style: none; padding: 0; margin: 12px 0 0; }
.lb-row {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  margin-bottom: 8px;
  background: var(--border-soft);
  border: 1px solid transparent;
  transition: background 0.25s ease, transform 0.25s ease;
  animation: lb-slide-in 0.3s ease-out;
}
@keyframes lb-slide-in {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: translateY(0); }
}
.lb-row.lb-me {
  background: var(--primary-light);
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}
.lb-rank {
  font-weight: 700;
  color: var(--muted);
  min-width: 40px;
  font-size: 15px;
}
.lb-row:nth-child(1) .lb-rank { color: #b45309; font-size: 18px; }
.lb-row:nth-child(2) .lb-rank { color: #475569; font-size: 17px; }
.lb-row:nth-child(3) .lb-rank { color: #92400e; font-size: 16px; }
.lb-info { flex: 1; min-width: 0; }
.lb-info strong { display: block; line-height: 1.3; }
.lb-score {
  font-weight: 700;
  font-size: 17px;
  color: var(--primary-dark);
  white-space: nowrap;
  text-align: right;
  line-height: 1.2;
}
.lb-row.lb-me .lb-score { color: var(--primary-dark); }

/* ===== AI RECOMMENDATION ===== */
.ai-empty {
  margin-top: 12px;
  padding: 12px 14px;
  background: var(--border-soft);
  border: 1px dashed #cbd5e1;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}

.ai-rec {
  margin-top: 12px;
  padding: 16px 18px;
  background: linear-gradient(135deg, #ede9fe 0%, #e0e7ff 100%);
  border-left: 3px solid var(--primary);
  border-radius: var(--radius-sm);
  font-size: 14.5px;
  color: #312e81;
  line-height: 1.6;
  white-space: pre-wrap;
}
.ai-rec-label {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--primary-dark);
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 6px;
}
.ai-rec-label::before {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), #a855f7);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

/* ===== EXPLANATION / PEMBAHASAN ===== */
.explanation {
  margin-top: 12px;
  padding: 14px 16px;
  background: linear-gradient(135deg, #fef9c3 0%, #fef3c7 100%);
  border-left: 3px solid var(--warning);
  border-radius: var(--radius-sm);
  font-size: 14px;
  color: #78350f;
  line-height: 1.55;
}
.explanation.small { margin-top: 8px; padding: 10px 12px; font-size: 13px; }
.explanation-label {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: #92400e;
  margin-bottom: 4px;
}

code {
  font-family: ui-monospace, "SF Mono", Menlo, monospace;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 640px) {
  .container { padding: 20px 16px; }
  .card { padding: 20px 18px; border-radius: var(--radius); }
  h1 { font-size: 22px; }
  .score-num { font-size: 44px; }
  .form-inline { flex-direction: column; }
  .form-inline input { min-width: 0; }
  .table { font-size: 13px; }
  .table th, .table td { padding: 10px 8px; }
  .actions { gap: 4px; }
  .btn { padding: 8px 12px; font-size: 13px; }
}

/* ===== ANIMATIONS ===== */
@keyframes slide-up {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}
.card { animation: slide-up 0.3s ease-out backwards; }
.card:nth-child(2) { animation-delay: 0.05s; }
.card:nth-child(3) { animation-delay: 0.1s; }
.card:nth-child(4) { animation-delay: 0.15s; }