:root{
  --bg: #f6f7fb;
  --card: #ffffff;
  --text: #1f2937;
  --muted: #6b7280;
  --primary: #2563eb;
  --primary-contrast: #fff;
  --border: #e5e7eb;
  --success: #10b981;
  --warning: #f59e0b;
  --error: #ef4444;
  --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -2px rgba(0,0,0,0.05);
}

*{box-sizing:border-box;}
body{margin:0; background:var(--bg); color:var(--text); font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, Apple Color Emoji, Segoe UI Emoji; line-height:1.6;}
.container{max-width: 1000px; margin: 24px auto; padding: 12px;}
.card{background:var(--card); border:1px solid var(--border); border-radius:16px; padding:32px; box-shadow: var(--shadow);}
h1,h2{margin-top:0; color:var(--text);}
h2{margin-top:32px; margin-bottom:16px; font-size:1.5rem;}
h3{margin-top:24px; margin-bottom:12px; font-size:1.25rem;}
label{display:block; margin:8px 0; font-weight:500; color:var(--text);}
input[type="text"], input[type="email"], input[type="password"], input[type="number"], textarea{
  padding:12px 16px; 
  border:1px solid var(--border); 
  border-radius:10px; 
  width:100%; 
  max-width:500px;
  font-size:14px;
  transition: border-color 0.2s, box-shadow 0.2s;
}
input:focus, textarea:focus{
  outline:none;
  border-color:var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}
textarea{resize:vertical; min-height:100px; font-family:inherit;}
.btn{
  background:var(--primary); 
  color:var(--primary-contrast); 
  padding:12px 24px; 
  border:none; 
  border-radius:10px; 
  cursor:pointer;
  font-size:14px;
  font-weight:500;
  transition: background 0.2s, transform 0.1s;
  box-shadow: var(--shadow);
}
.btn:hover{background:#1d4ed8; transform:translateY(-1px);}
.btn:active{transform:translateY(0);}
.btn.secondary{background:#e5e7eb; color:#111827;}
.btn.secondary:hover{background:#d1d5db;}
.btn.small{padding:8px 16px; font-size:13px;}
.btn:disabled{opacity:.6; cursor:not-allowed; transform:none;}
.actions{margin-top:16px; display:flex; gap:8px; flex-wrap:wrap;}
.badge{display:inline-block; background:#eef2ff; color:#3730a3; padding:6px 12px; border-radius:999px; font-size:14px; margin:8px 0; font-weight:500;}
.question{padding:20px; border:1px solid var(--border); border-radius:12px; margin:16px 0; background:var(--card); transition: box-shadow 0.2s;}
.question:hover{box-shadow: var(--shadow);}
.options{display:grid; gap:10px; margin-top:12px;}
.option{
  display:flex; 
  gap:12px; 
  align-items:flex-start; 
  padding:12px; 
  border:1px solid var(--border); 
  border-radius:8px;
  cursor:pointer;
  transition: background 0.2s, border-color 0.2s;
}
.option:hover{background:#f9fafb; border-color:var(--primary);}
.option-letter{
  font-weight:bold;
  color:var(--primary);
  min-width:24px;
  flex-shrink:0;
}
.option-text{
  flex:1;
}
.option input[type="radio"], .option input[type="checkbox"]{cursor:pointer; margin-top:2px;}
.result{margin-top:16px; font-weight:600;}
table{width:100%; border-collapse:collapse; margin-top:16px; background:var(--card); border-radius:8px; overflow:hidden;}
th{background:#f9fafb; padding:12px; border-bottom:2px solid var(--border); text-align:left; font-weight:600; color:var(--text);}
td{padding:12px; border-bottom:1px solid var(--border); text-align:left;}
tr:hover{background:#f9fafb;}
a.link{color:var(--primary); text-decoration:none; font-weight:500;}
a.link:hover{text-decoration:underline;}
.site-header{background:#111827; border-radius:14px; padding:16px 24px; margin-bottom:24px; display:flex; align-items:center; justify-content:space-between; box-shadow: var(--shadow);}
.site-header .brand{display:flex; gap:14px; align-items:center;}
.logo{height:32px; object-fit:contain;}
.logo.dark-bg{filter:none;}

/* Admin Section */
.admin-section{margin-top:32px; padding-top:32px; border-top:1px solid var(--border);}
.admin-section:first-of-type{margin-top:0; padding-top:0; border-top:none;}
.settings-form{display:flex; flex-direction:column; gap:16px; max-width:500px;}

/* Question Management */
.questions-list{display:flex; flex-direction:column; gap:12px; margin-top:16px;}
.question-item{
  padding:16px; 
  border:1px solid var(--border); 
  border-radius:10px; 
  background:var(--card);
  transition: box-shadow 0.2s;
}
.question-item:hover{box-shadow: var(--shadow);}
.question-item-header{
  display:flex; 
  justify-content:space-between; 
  align-items:center; 
  gap:16px;
  flex-wrap:wrap;
}
.question-actions{display:flex; gap:8px;}

/* Modal */
.modal{
  display:none;
  position:fixed;
  z-index:1000;
  left:0;
  top:0;
  width:100%;
  height:100%;
  background-color:rgba(0,0,0,0.5);
  backdrop-filter:blur(4px);
  animation:fadeIn 0.2s;
  align-items:center;
  justify-content:center;
}
.modal[style*="display: flex"], .modal.show{
  display:flex !important;
}
@keyframes fadeIn{
  from{opacity:0;}
  to{opacity:1;}
}
.modal-content{
  background-color:var(--card);
  margin:5% auto;
  padding:32px;
  border-radius:16px;
  width:90%;
  max-width:600px;
  max-height:90vh;
  overflow-y:auto;
  box-shadow:var(--shadow-lg);
  animation:slideDown 0.3s;
}
.modal-header{
  display:flex;
  justify-content:space-between;
  align-items:center;
  margin-bottom:24px;
  padding-bottom:16px;
  border-bottom:1px solid var(--border);
}
.modal-header h2{
  margin:0;
  font-size:1.5rem;
}
.modal-close{
  background:none;
  border:none;
  font-size:28px;
  cursor:pointer;
  color:var(--muted);
  padding:0;
  width:32px;
  height:32px;
  display:flex;
  align-items:center;
  justify-content:center;
  border-radius:8px;
  transition:background 0.2s, color 0.2s;
}
.modal-close:hover{
  background:var(--bg);
  color:var(--text);
}
.modal-actions{
  display:flex;
  gap:12px;
  justify-content:flex-end;
  margin-top:24px;
  padding-top:16px;
  border-top:1px solid var(--border);
}
@keyframes slideDown{
  from{transform:translateY(-20px); opacity:0;}
  to{transform:translateY(0); opacity:1;}
}
.close-modal{
  color:#aaa;
  float:right;
  font-size:28px;
  font-weight:bold;
  cursor:pointer;
  line-height:1;
}
.close-modal:hover{color:var(--text);}

/* Instructions Page */
.instructions-section{
  margin:32px 0;
  padding:24px;
  background:var(--bg);
  border-radius:12px;
  border-left:4px solid var(--primary);
}
.instructions-section h2{
  margin-top:0;
  margin-bottom:16px;
  color:var(--primary);
  font-size:1.25rem;
}
.instructions-section h3{
  margin-top:16px;
  margin-bottom:8px;
  font-size:1.1rem;
  color:var(--text);
}
.instructions-section ul{
  margin:12px 0;
  padding-left:24px;
}
.instructions-section li{
  margin:8px 0;
  line-height:1.6;
}
.instructions-actions{
  display:flex;
  gap:12px;
  justify-content:center;
  margin-top:40px;
  padding-top:32px;
  border-top:2px solid var(--border);
}

/* Results Page */
.results-card{text-align:center;}
.loading{font-size:18px; color:var(--muted); padding:40px;}
.error{color:var(--error); padding:40px; font-size:16px;}
.congratulations{
  margin-bottom:32px;
  padding:32px;
  background:linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius:16px;
  color:white;
  opacity:0;
  transform:scale(0.9);
  transition:opacity 0.5s, transform 0.5s;
}
.congratulations.animate-in{
  opacity:1;
  transform:scale(1);
}
.celebration-icon{font-size:64px; margin-bottom:16px; animation:bounce 1s ease-in-out;}
@keyframes bounce{
  0%, 100%{transform:translateY(0);}
  50%{transform:translateY(-20px);}
}
.celebration-title{font-size:2.5rem; margin:16px 0; color:white;}
.celebration-text{font-size:1.25rem; margin:8px 0; color:rgba(255,255,255,0.9);}
.results-content{margin-top:32px;}
.participant-info{
  margin:24px 0;
  padding:16px;
  background:#f9fafb;
  border-radius:10px;
  text-align:left;
  max-width:500px;
  margin-left:auto;
  margin-right:auto;
}
.info-item{margin:8px 0; color:var(--text);}
.score-container{
  display:flex;
  flex-direction:column;
  align-items:center;
  gap:32px;
  margin:40px 0;
}
.score-circle{
  width:200px;
  height:200px;
  border-radius:50%;
  background:linear-gradient(135deg, var(--primary) 0%, #1d4ed8 100%);
  display:flex;
  flex-direction:column;
  align-items:center;
  justify-content:center;
  color:white;
  box-shadow:var(--shadow-lg);
  animation:scaleIn 0.5s ease-out;
}
@keyframes scaleIn{
  from{transform:scale(0);}
  to{transform:scale(1);}
}
.score-value{font-size:3rem; font-weight:bold; line-height:1;}
.score-label{font-size:1rem; margin-top:8px; opacity:0.9;}
.score-details{
  display:grid;
  grid-template-columns:repeat(auto-fit, minmax(200px, 1fr));
  gap:16px;
  width:100%;
  max-width:600px;
}
.score-item{
  padding:16px;
  background:#f9fafb;
  border-radius:10px;
  border:1px solid var(--border);
}
.score-label-small{display:block; color:var(--muted); font-size:14px; margin-bottom:8px;}
.score-number{font-size:1.5rem; font-weight:bold; color:var(--primary);}
.remaining-attempts{margin:24px 0;}
.attempts-badge{
  display:inline-block;
  padding:12px 24px;
  background:#eef2ff;
  color:#3730a3;
  border-radius:10px;
  font-size:16px;
}
.attempts-badge.no-attempts{
  background:#fee2e2;
  color:#991b1b;
}

/* Exam Page - One Question Per Page */
.exam-header{
  display:flex;
  justify-content:space-between;
  align-items:flex-start;
  margin-bottom:24px;
  flex-wrap:wrap;
  gap:16px;
}
.timer-badge{
  display:inline-block;
  background:#eef2ff;
  color:#3730a3;
  padding:10px 16px;
  border-radius:10px;
  font-size:16px;
  font-weight:600;
  min-width:140px;
  text-align:center;
  transition:background 0.3s, color 0.3s;
}
.timer-badge.timer-warning{
  background:#fee2e2;
  color:#991b1b;
  animation:pulse 1s infinite;
}
@keyframes pulse{
  0%, 100%{opacity:1;}
  50%{opacity:0.8;}
}

/* Progress Bar */
.progress-container{
  margin:24px 0;
}
.progress-bar{
  width:100%;
  height:12px;
  background:#e5e7eb;
  border-radius:999px;
  overflow:hidden;
  margin-bottom:8px;
}
.progress-fill{
  height:100%;
  background:linear-gradient(90deg, var(--primary) 0%, #1d4ed8 100%);
  border-radius:999px;
  transition:width 0.3s ease;
  width:0%;
}
.progress-text{
  text-align:center;
  color:var(--muted);
  font-size:14px;
}

/* Question Navigation Panel */
.question-nav-panel{
  background:#f9fafb;
  border:1px solid var(--border);
  border-radius:12px;
  padding:16px;
  margin:24px 0;
}
.question-nav-header{
  display:flex;
  justify-content:space-between;
  align-items:center;
  margin-bottom:12px;
  flex-wrap:wrap;
  gap:12px;
}
.nav-legend{
  display:flex;
  gap:16px;
  font-size:13px;
  flex-wrap:wrap;
}
.legend-item{
  display:flex;
  align-items:center;
  gap:6px;
}
.legend-icon{
  width:20px;
  height:20px;
  border-radius:4px;
  display:inline-block;
}
.legend-icon.answered{
  background:#10b981;
  border:2px solid #059669;
}
.legend-icon.skipped{
  background:#f59e0b;
  border:2px solid #d97706;
}
.legend-icon.current{
  background:var(--primary);
  border:2px solid #1d4ed8;
}
.question-nav-grid{
  display:grid;
  grid-template-columns:repeat(auto-fill, 40px);
  gap:8px;
  justify-content:start;
  max-width:100%;
}
.question-nav-item{
  width:40px;
  height:40px;
  display:flex;
  align-items:center;
  justify-content:center;
  border:2px solid var(--border);
  border-radius:8px;
  background:white;
  cursor:pointer;
  font-weight:500;
  transition:all 0.2s;
  font-size:14px;
}
.question-nav-item:hover{
  border-color:var(--primary);
  transform:translateY(-2px);
  box-shadow:var(--shadow);
}
.question-nav-item.answered{
  background:#10b981;
  color:white;
  border-color:#059669;
}
.question-nav-item.skipped{
  background:#f59e0b;
  color:white;
  border-color:#d97706;
}
.question-nav-item.current{
  background:var(--primary);
  color:white;
  border-color:#1d4ed8;
  box-shadow:0 0 0 3px rgba(37, 99, 235, 0.2);
}

.question-nav-compact{
  display:none;
  gap:12px;
  margin-top:8px;
  justify-content:center;
  align-items:center;
}
.nav-status-btn{
  display:flex;
  align-items:center;
  justify-content:center;
  padding:0;
  border:none;
  background:transparent;
  cursor:pointer;
  transition:transform 0.2s;
  min-width:0;
}
.nav-status-btn:active{
  transform:scale(0.95);
}
.status-circle{
  width:36px;
  height:36px;
  border-radius:50%;
  display:flex;
  align-items:center;
  justify-content:center;
  border:2px solid;
  transition:all 0.2s;
}
.status-circle.answered{
  background:#10b981;
  border-color:#059669;
  color:white;
}
.status-circle.skipped{
  background:#f59e0b;
  border-color:#d97706;
  color:white;
}
.status-circle.unanswered{
  background:#e5e7eb;
  border-color:#d1d5db;
  color:#6b7280;
}
.status-count{
  font-weight:700;
  font-size:14px;
  line-height:1;
}

@media (max-width:768px){
  .mobile-only{
    display:flex !important;
  }
  .desktop-only{
    display:none !important;
  }
  .question-nav-panel{
    padding:12px;
  }
  .question-nav-header{
    margin-bottom:8px;
  }
  .question-nav-header strong{
    font-size:14px;
  }
}
@media (min-width:769px){
  .mobile-only{
    display:none !important;
  }
  .desktop-only{
    display:block !important;
  }
  .question-nav-grid.desktop-only{
    display:grid !important;
  }
}

/* Question Container - One Per Page */
.question-container{
  margin:32px 0;
  min-height:300px;
  display:block !important;
}
.question-page{
  padding:24px;
  background:white;
  border:1px solid var(--border);
  border-radius:12px;
}
.question-header{
  font-size:18px;
  color:var(--muted);
  margin-bottom:16px;
}
.question-text{
  font-size:18px;
  line-height:1.6;
  margin-bottom:24px;
  color:var(--text);
  font-weight:500;
}

/* Exam Actions */
.exam-actions{
  display:flex;
  justify-content:center;
  align-items:center;
  margin-top:32px;
  padding-top:24px;
  border-top:1px solid var(--border);
  flex-wrap:wrap;
  gap:12px;
  position:relative;
}
.exam-actions .btn{
  min-width:120px;
}
.exam-actions .btn-primary{
  min-width:150px;
  font-size:16px;
  font-weight:600;
  padding:12px 24px;
  order:2;
}
.exam-actions #prev-btn{
  order:1;
}
.exam-actions #skip-btn{
  order:3;
}
.exam-actions #review-btn,
.exam-actions #back-to-exam-btn,
.exam-actions #submit-btn{
  order:4;
  margin-left:auto;
}

/* Review Page */
.review-container{
  margin:32px 0;
}
.review-questions{
  display:flex;
  flex-direction:column;
  gap:16px;
  margin:24px 0;
}
.review-item{
  padding:20px;
  border:1px solid var(--border);
  border-radius:12px;
  background:white;
}
.review-item-header{
  display:flex;
  justify-content:space-between;
  align-items:center;
  margin-bottom:12px;
  flex-wrap:wrap;
  gap:12px;
}
.review-status{
  padding:6px 12px;
  border-radius:6px;
  font-size:13px;
  font-weight:500;
}
.review-status.answered{
  background:#d1fae5;
  color:#065f46;
}
.review-status.skipped{
  background:#fef3c7;
  color:#92400e;
}
.review-question-text{
  font-size:16px;
  margin-bottom:12px;
  color:var(--text);
  line-height:1.5;
}
.review-answer{
  padding:12px;
  background:#f9fafb;
  border-radius:8px;
  margin-bottom:12px;
  color:var(--text);
}
.skipped-warning{
  padding:16px;
  background:#fef3c7;
  border:2px solid #f59e0b;
  border-radius:10px;
  color:#92400e;
  margin:24px 0;
  font-size:15px;
}

/* Login Page */
.login-card{
  max-width:400px;
  margin:60px auto;
}
.error-message{
  padding:12px;
  background:#fee2e2;
  color:#991b1b;
  border-radius:8px;
  margin:12px 0;
  font-size:14px;
}

/* Dashboard */
.dashboard-header{
  display:flex;
  justify-content:space-between;
  align-items:center;
  margin-bottom:32px;
  flex-wrap:wrap;
  gap:16px;
}
.dashboard-actions{
  display:flex;
  gap:12px;
  flex-wrap:wrap;
}

/* Import Questions Page */
.import-instructions{
  background:#f9fafb;
  border:1px solid var(--border);
  border-radius:12px;
  padding:24px;
  margin-bottom:24px;
}
.import-instructions ul{
  margin:12px 0;
  padding-left:24px;
}
.import-instructions li{
  margin:8px 0;
}
.example-box{
  background:white;
  border:1px solid var(--border);
  border-radius:8px;
  padding:16px;
  margin-top:16px;
  font-family:monospace;
  font-size:13px;
  line-height:1.8;
  white-space:pre-wrap;
}
.paste-toolbar{
  display:flex;
  justify-content:space-between;
  align-items:center;
  margin-bottom:8px;
  flex-wrap:wrap;
  gap:8px;
}
.paste-hint{
  font-size:13px;
  color:var(--muted);
  font-style:italic;
}
.questions-editor{
  min-height:400px;
  padding:16px;
  border:2px solid var(--border);
  border-radius:10px;
  background:white;
  font-size:14px;
  line-height:1.8;
  white-space:pre-wrap;
  overflow-y:auto;
  max-height:600px;
  font-family:inherit;
  word-wrap:break-word;
}
.questions-editor:empty:not(:focus):before{
  content:attr(placeholder);
  color:#9ca3af;
  pointer-events:none;
}
.questions-editor:focus{
  outline:none;
  border-color:var(--primary);
  box-shadow:0 0 0 3px rgba(37, 99, 235, 0.1);
}
.questions-editor strong,
.questions-editor b{
  font-weight:bold;
  color:var(--primary);
}
.parsed-results{
  margin-top:32px;
  padding-top:32px;
  border-top:2px solid var(--border);
}
.parsed-question-item{
  background:white;
  border:1px solid var(--border);
  border-radius:12px;
  padding:20px;
  margin:16px 0;
}
.parsed-question-header{
  display:flex;
  justify-content:space-between;
  align-items:center;
  margin-bottom:12px;
  flex-wrap:wrap;
  gap:8px;
}
.question-meta{
  font-size:13px;
  color:var(--muted);
}
.case-study-preview{
  background:#eef2ff;
  border-left:4px solid var(--primary);
  padding:12px;
  margin:12px 0;
  border-radius:4px;
}
.case-study-text{
  margin-top:8px;
  font-size:14px;
  color:var(--text);
  line-height:1.6;
}
.parsed-question-text{
  font-size:16px;
  margin:16px 0;
  line-height:1.6;
  color:var(--text);
}
.parsed-options{
  display:flex;
  flex-direction:column;
  gap:8px;
  margin-top:12px;
}
.parsed-option{
  padding:10px;
  background:#f9fafb;
  border-radius:6px;
  border:1px solid var(--border);
}
.parsed-option.correct{
  background:#d1fae5;
  border-color:#10b981;
  font-weight:500;
}
.success-message{
  padding:16px;
  background:#d1fae5;
  color:#065f46;
  border-radius:10px;
  margin:24px 0;
  font-size:15px;
}

/* Case Study in Exam */
.case-study{
  background:#f0f9ff;
  border:1px solid #bae6fd;
  border-radius:12px;
  padding:20px;
  margin-bottom:24px;
}
.case-study-header{
  font-weight:600;
  color:var(--primary);
  margin-bottom:12px;
  font-size:16px;
}
.case-study-content{
  color:var(--text);
  line-height:1.8;
  font-size:15px;
  white-space:pre-wrap;
}

/* Questions Review Page */
.review-summary{
  padding:16px;
  background:#f9fafb;
  border-radius:10px;
  margin-bottom:24px;
  font-size:16px;
  color:var(--text);
}
.questions-review-list{
  display:flex;
  flex-direction:column;
  gap:24px;
}
.review-question-card{
  background:white;
  border:2px solid var(--border);
  border-radius:12px;
  padding:24px;
  transition:box-shadow 0.2s;
}
.review-question-card:hover{
  box-shadow:var(--shadow-lg);
}
.review-question-header{
  display:flex;
  justify-content:space-between;
  align-items:center;
  margin-bottom:16px;
  padding-bottom:12px;
  border-bottom:2px solid var(--border);
}
.question-number{
  font-size:20px;
  font-weight:600;
  color:var(--primary);
}
.question-type-badge{
  padding:4px 12px;
  background:#eef2ff;
  color:#3730a3;
  border-radius:6px;
  font-size:12px;
  font-weight:500;
}
.review-case-study{
  background:#f0f9ff;
  border:1px solid #bae6fd;
  border-left:4px solid var(--primary);
  border-radius:8px;
  padding:16px;
  margin-bottom:20px;
}
.review-case-study-header{
  font-weight:600;
  color:var(--primary);
  margin-bottom:12px;
  font-size:15px;
}
.review-case-study-content{
  color:var(--text);
  line-height:1.8;
  font-size:14px;
  white-space:pre-wrap;
}
.review-question-text{
  font-size:18px;
  line-height:1.6;
  margin-bottom:20px;
  color:var(--text);
  font-weight:500;
}
.review-options-container{
  display:flex;
  flex-direction:column;
  gap:12px;
}
.review-option{
  display:flex;
  align-items:flex-start;
  gap:12px;
  padding:14px;
  background:#f9fafb;
  border:2px solid var(--border);
  border-radius:8px;
  transition:all 0.2s;
}
.review-option.correct-answer{
  background:#d1fae5;
  border-color:#10b981;
  box-shadow:0 0 0 3px rgba(16, 185, 129, 0.1);
}
.option-letter{
  font-weight:600;
  color:var(--text);
  min-width:24px;
}
.review-option.correct-answer .option-letter{
  color:#065f46;
}
.option-text{
  flex:1;
  color:var(--text);
  line-height:1.5;
}
.review-option.correct-answer .option-text{
  color:#065f46;
  font-weight:500;
}
.correct-badge{
  padding:4px 10px;
  background:#10b981;
  color:white;
  border-radius:6px;
  font-size:12px;
  font-weight:600;
  white-space:nowrap;
}