:root {
    --primary: #1a56db;
    --primary-dark: #12409c;
    --danger: #dc2626;
    --amber: #d97706;
    --green: #16a34a;
    --gray-bg: #f4f6f9;
    --border: #e2e5eb;
    --text: #1f2937;
    --text-muted: #6b7280;
    font-family: -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }
body { margin: 0; background: var(--gray-bg); color: var(--text); }

a { color: var(--primary); text-decoration: none; }
.muted { color: var(--text-muted); }
.small { font-size: 0.85rem; }
kbd { background: #eef0f4; border: 1px solid var(--border); border-radius: 4px; padding: 1px 6px; font-size: 0.75rem; }

/* ---------- Buttons ---------- */
.btn { display: inline-block; padding: 10px 18px; border-radius: 8px; border: none; font-weight: 600; cursor: pointer; font-size: 0.95rem; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-secondary { background: #fff; border: 1px solid var(--border); color: var(--text); }
.btn-danger { background: var(--danger); color: #fff; }
.btn-flag { background: #fff7ed; border: 1px solid #fdba74; color: #9a3412; }
.btn-flag-active { background: #fdba74; }
.btn-block { width: 100%; }
.btn:disabled { opacity: 0.4; cursor: not-allowed; }

/* ---------- Nav ---------- */
.navbar { display: flex; justify-content: space-between; align-items: center; padding: 14px 28px; background: #fff; border-bottom: 1px solid var(--border); }
.brand { font-weight: 800; color: var(--primary); font-size: 1.1rem; }

/* ---------- Auth ---------- */
.auth-page { display: flex; align-items: center; justify-content: center; min-height: 100vh; }
.auth-card { background: #fff; padding: 40px; border-radius: 14px; box-shadow: 0 4px 24px rgba(0,0,0,0.06); width: 380px; }
.auth-card h1 { margin: 0 0 6px; }
.auth-card form { display: flex; flex-direction: column; gap: 10px; margin-top: 16px; }
.auth-card label { font-weight: 600; font-size: 0.85rem; }
.auth-card input { padding: 10px 12px; border-radius: 8px; border: 1px solid var(--border); font-size: 0.95rem; }

.alert { padding: 10px 14px; border-radius: 8px; margin-bottom: 10px; font-size: 0.9rem; }
.alert-error { background: #fef2f2; color: #991b1b; border: 1px solid #fecaca; }
.alert-success { background: #f0fdf4; color: #166534; border: 1px solid #bbf7d0; }

/* ---------- Container/Dashboard ---------- */
.container { max-width: 1100px; margin: 0 auto; padding: 32px 24px; }
.container-narrow { max-width: 640px; }
.section-title { margin-top: 40px; }

.card-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 18px; }
.exam-card, .subject-card { background: #fff; border: 1px solid var(--border); border-radius: 12px; padding: 20px; }
.exam-card h2 { margin: 0 0 6px; }
.price-tag { font-size: 1.3rem; font-weight: 800; color: var(--primary); margin: 10px 0; }

.table { width: 100%; border-collapse: collapse; background: #fff; border-radius: 10px; overflow: hidden; }
.table th, .table td { padding: 12px 14px; border-bottom: 1px solid var(--border); text-align: left; font-size: 0.92rem; }

.badge { display: inline-block; padding: 3px 10px; border-radius: 20px; font-size: 0.75rem; font-weight: 700; text-transform: capitalize; }
.badge-green { background: #dcfce7; color: #166534; }
.badge-red { background: #fee2e2; color: #991b1b; }
.badge-amber { background: #fef3c7; color: #92400e; }
.badge-gray { background: #f1f5f9; color: #475569; }

/* ---------- Setup form ---------- */
.setup-form { background: #fff; padding: 24px; border-radius: 12px; border: 1px solid var(--border); display: flex; flex-direction: column; gap: 8px; }
.setup-form label { font-weight: 600; margin-top: 8px; }
.setup-form input[type="number"] { padding: 8px 12px; border-radius: 8px; border: 1px solid var(--border); }
.checkbox-list { display: grid; grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); gap: 8px; margin: 6px 0; }
.checkbox-item { display: flex; align-items: center; gap: 8px; background: #f8fafc; padding: 8px 12px; border-radius: 8px; font-weight: 500; }

/* ============================================================
   EXAM SCREEN — modeled on real CBT-hall software
   ============================================================ */
.exam-body { background: #eef1f6; height: 100vh; overflow: hidden; }
.exam-header { display: flex; align-items: center; justify-content: space-between; background: #0f2557; color: #fff; padding: 12px 24px; }
.exam-header .brand { color: #fff; }

.timer { font-family: "Courier New", monospace; font-size: 1.6rem; font-weight: 800; background: #16326b; padding: 6px 18px; border-radius: 8px; letter-spacing: 2px; }
.timer-warning { background: #92400e; }
.timer-danger { background: var(--danger); animation: pulse 1s infinite; }
@keyframes pulse { 0%,100% { opacity: 1; } 50% { opacity: 0.6; } }

.exam-layout { display: grid; grid-template-columns: 260px 1fr; height: calc(100vh - 58px); }

.palette-panel { background: #fff; border-right: 1px solid var(--border); padding: 18px; overflow-y: auto; }
.palette-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 8px; margin: 14px 0; }
.palette-cell { aspect-ratio: 1; border-radius: 6px; border: 1px solid var(--border); background: #f8fafc; font-weight: 700; cursor: pointer; font-size: 0.85rem; }
.cell-current { background: var(--primary); color: #fff; border-color: var(--primary); }
.cell-answered { background: #dcfce7; border-color: #86efac; color: #166534; }
.cell-flagged { background: #fef3c7; border-color: #fcd34d; color: #92400e; }
.cell-unanswered { background: #fff; }

.legend { display: flex; flex-direction: column; gap: 6px; margin-top: 20px; font-size: 0.8rem; }
.legend span { display: flex; align-items: center; gap: 8px; }
.dot { width: 12px; height: 12px; border-radius: 3px; display: inline-block; }
.dot-current { background: var(--primary); }
.dot-answered { background: #86efac; }
.dot-flagged { background: #fcd34d; }
.dot-unanswered { background: #fff; border: 1px solid var(--border); }

.question-panel { padding: 32px 48px; overflow-y: auto; }

.passage-panel { background: #f8fafc; border: 1px solid var(--border); border-radius: 12px; padding: 20px 24px; margin-bottom: 24px; max-width: 720px; }
.passage-panel.hidden { display: none; }
.passage-panel h3 { margin: 0 0 10px; color: var(--primary-dark); }
.passage-text { line-height: 1.7; color: #374151; max-height: 260px; overflow-y: auto; white-space: pre-wrap; }
.passage-text.hidden { display: none; }
#passageAudio { width: 100%; margin-bottom: 10px; }
#passageAudio.hidden { display: none; }

.q-meta { display: flex; justify-content: space-between; margin-bottom: 14px; }
.subject-tag { background: #dbeafe; color: #1e40af; padding: 4px 12px; border-radius: 20px; font-weight: 700; font-size: 0.8rem; }
.q-text { font-size: 1.25rem; line-height: 1.6; margin-bottom: 24px; font-weight: 500; }

.q-options { display: flex; flex-direction: column; gap: 12px; max-width: 720px; }
.option-item { display: flex; align-items: center; gap: 14px; background: #fff; border: 2px solid var(--border); border-radius: 10px; padding: 14px 18px; cursor: pointer; }
.option-item:hover { border-color: #93c5fd; }
.option-selected { border-color: var(--primary); background: #eff6ff; }
.option-letter { width: 30px; height: 30px; border-radius: 50%; background: #f1f5f9; display: flex; align-items: center; justify-content: center; font-weight: 800; flex-shrink: 0; }
.option-selected .option-letter { background: var(--primary); color: #fff; }

.nav-buttons { display: flex; gap: 12px; margin-top: 32px; }

/* ---------- Modal ---------- */
.modal { position: fixed; inset: 0; background: rgba(15,23,42,0.5); display: flex; align-items: center; justify-content: center; z-index: 50; }
.modal.hidden { display: none; }
.modal-box { background: #fff; padding: 28px; border-radius: 14px; width: 380px; }
.modal-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 20px; }

/* ---------- Results ---------- */
.results-summary { display: flex; align-items: center; gap: 28px; background: #fff; padding: 28px; border-radius: 14px; border: 1px solid var(--border); }
.score-ring { width: 110px; height: 110px; border-radius: 50%; display: flex; align-items: center; justify-content: center; border: 8px solid; flex-shrink: 0; }
.score-ring-green { border-color: var(--green); }
.score-ring-amber { border-color: var(--amber); }
.score-ring-red { border-color: var(--danger); }
.score-pct { font-size: 1.4rem; font-weight: 800; }

.bar-track { background: #f1f5f9; height: 10px; border-radius: 8px; overflow: hidden; margin: 10px 0; }
.bar-fill { background: var(--primary); height: 100%; }

.review-list { display: flex; flex-direction: column; gap: 12px; }
.review-item { background: #fff; border-radius: 10px; padding: 16px 20px; border-left: 5px solid var(--border); }
.review-correct { border-left-color: var(--green); }
.review-wrong { border-left-color: var(--danger); }
.review-skipped { border-left-color: #94a3b8; }
.review-head { display: flex; justify-content: space-between; font-weight: 700; margin-bottom: 8px; font-size: 0.85rem; }
.review-question { font-weight: 500; }
.explanation { background: #f8fafc; padding: 10px 12px; border-radius: 8px; margin-top: 6px; }

@media (max-width: 860px) {
    .exam-layout { grid-template-columns: 1fr; }
    .palette-panel { display: none; }
    .question-panel { padding: 20px; }
}