/* ===== Reset & Base ===== */
* { margin: 0; padding: 0; box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
html { font-size: 16px; }
body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  background: #f0f2f5;
  color: #333;
  line-height: 1.6;
  max-width: 480px;
  margin: 0 auto;
  min-height: 100vh;
  position: relative;
}
:root {
  --primary: #4a90d9;
  --primary-dark: #357abd;
  --primary-light: #e8f1fc;
  --success: #52c41a;
  --success-bg: #f6ffed;
  --error: #ff4d4f;
  --error-bg: #fff2f0;
  --warning: #faad14;
  --warning-bg: #fffbe6;
  --text-main: #333;
  --text-secondary: #666;
  --text-hint: #999;
  --border: #e8e8e8;
  --bg-card: #fff;
  --shadow: 0 2px 8px rgba(0,0,0,0.08);
  --radius: 12px;
}

/* ===== Views ===== */
.view { display: none; min-height: 100vh; padding-bottom: 20px; }
.view.active { display: block; }

/* ===== Header ===== */
.app-header {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  padding: 20px 16px 16px;
  position: sticky;
  top: 0;
  z-index: 100;
}
.app-header h1 { font-size: 18px; font-weight: 600; }
.app-header .subtitle { font-size: 12px; opacity: 0.85; margin-top: 2px; }
.app-header .back-btn {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 24px;
  cursor: pointer;
  opacity: 0.9;
  background: none;
  border: none;
  color: #fff;
  padding: 4px 8px;
}
.app-header .home-btn {
  position: absolute;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 20px;
  cursor: pointer;
  opacity: 0.9;
  background: none;
  border: none;
  color: #fff;
  padding: 4px 8px;
  line-height: 1;
}

/* ===== Home ===== */
.home-hero {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  padding: 40px 20px 30px;
  text-align: center;
}
.home-hero .icon { font-size: 48px; margin-bottom: 8px; }
.home-hero h2 { font-size: 22px; font-weight: 700; }
.home-hero p { font-size: 13px; opacity: 0.85; margin-top: 4px; }

.home-stats {
  display: flex;
  justify-content: space-around;
  padding: 16px;
  background: #fff;
  margin: -16px 12px 0;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  position: relative;
  z-index: 10;
}
.home-stats .stat { text-align: center; }
.home-stats .stat .num { font-size: 20px; font-weight: 700; color: var(--primary); }
.home-stats .stat .label { font-size: 11px; color: var(--text-hint); margin-top: 2px; }

.menu-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  padding: 16px 12px;
}
.menu-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 20px 16px;
  text-align: center;
  box-shadow: var(--shadow);
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s;
  border: none;
  width: 100%;
}
.menu-card:active { transform: scale(0.97); }
.menu-card .icon { font-size: 36px; margin-bottom: 8px; display: block; }
.menu-card .title { font-size: 15px; font-weight: 600; color: var(--text-main); }
.menu-card .desc { font-size: 11px; color: var(--text-hint); margin-top: 4px; }

.menu-card.blue .icon { color: var(--primary); }
.menu-card.green .icon { color: var(--success); }
.menu-card.orange .icon { color: var(--warning); }
.menu-card.red .icon { color: var(--error); }
.menu-card.purple .icon { color: #722ed1; }
.menu-card.teal .icon { color: #13c2c2; }

/* ===== Topic List ===== */
.topic-list { padding: 12px; }
.topic-item {
  background: #fff;
  border-radius: var(--radius);
  padding: 16px;
  margin-bottom: 10px;
  box-shadow: var(--shadow);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: transform 0.15s;
}
.topic-item:active { transform: scale(0.98); }
.topic-item .info .name { font-size: 15px; font-weight: 600; }
.topic-item .info .meta { font-size: 12px; color: var(--text-hint); margin-top: 2px; }
.topic-item .arrow { color: var(--text-hint); font-size: 20px; }
.topic-item .badge {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 10px;
  font-size: 11px;
  font-weight: 600;
  margin-right: 6px;
}
.badge-single { background: var(--primary-light); color: var(--primary); }
.badge-judge { background: var(--warning-bg); color: var(--warning); }
.badge-multi { background: #f9f0ff; color: #722ed1; }

/* ===== Question Card ===== */
.question-container { padding: 12px; }
.progress-bar {
  height: 4px;
  background: var(--border);
  border-radius: 2px;
  margin-bottom: 12px;
  overflow: hidden;
}
.progress-bar .fill {
  height: 100%;
  background: var(--primary);
  border-radius: 2px;
  transition: width 0.3s;
}
.question-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 10px;
  font-size: 12px;
  color: var(--text-hint);
}
.question-meta .q-index { font-weight: 600; color: var(--primary); }
.question-meta .q-type-badge {
  padding: 2px 8px;
  border-radius: 10px;
  font-size: 11px;
  font-weight: 600;
}
.question-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 20px 16px;
  box-shadow: var(--shadow);
  margin-bottom: 12px;
}
.question-text {
  font-size: 16px;
  line-height: 1.7;
  margin-bottom: 16px;
  color: var(--text-main);
}
.options-list { list-style: none; }
.option-item {
  display: flex;
  align-items: flex-start;
  padding: 12px 14px;
  border: 2px solid var(--border);
  border-radius: 10px;
  margin-bottom: 10px;
  cursor: pointer;
  transition: all 0.2s;
  font-size: 14px;
}
.option-item:active { transform: scale(0.98); }
.option-item .option-label {
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: #f5f5f5;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 14px;
  margin-right: 10px;
  color: var(--text-secondary);
}
.option-item .option-text { flex: 1; line-height: 1.5; padding-top: 3px; }
.option-item.selected {
  border-color: var(--primary);
  background: var(--primary-light);
}
.option-item.selected .option-label {
  background: var(--primary);
  color: #fff;
}
.option-item.correct {
  border-color: var(--success);
  background: var(--success-bg);
}
.option-item.correct .option-label {
  background: var(--success);
  color: #fff;
}
.option-item.wrong {
  border-color: var(--error);
  background: var(--error-bg);
}
.option-item.wrong .option-label {
  background: var(--error);
  color: #fff;
}
.option-item.disabled { cursor: default; }

/* True/False options */
.tf-options {
  display: flex;
  gap: 12px;
  margin-top: 8px;
}
.tf-option {
  flex: 1;
  padding: 16px;
  border: 2px solid var(--border);
  border-radius: 10px;
  text-align: center;
  cursor: pointer;
  font-size: 16px;
  font-weight: 600;
  transition: all 0.2s;
}
.tf-option:active { transform: scale(0.97); }
.tf-option.selected { border-color: var(--primary); background: var(--primary-light); color: var(--primary); }
.tf-option.correct { border-color: var(--success); background: var(--success-bg); color: var(--success); }
.tf-option.wrong { border-color: var(--error); background: var(--error-bg); color: var(--error); }
.tf-option.disabled { cursor: default; }

/* ===== Answer Card (memorize mode) ===== */
.answer-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 16px;
  box-shadow: var(--shadow);
  margin-bottom: 12px;
  border-left: 4px solid var(--success);
}
.answer-card .label {
  font-size: 12px;
  color: var(--success);
  font-weight: 600;
  margin-bottom: 6px;
}
.answer-card .answer-text { font-size: 15px; color: var(--text-main); }

.explanation-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 16px;
  box-shadow: var(--shadow);
  border-left: 4px solid var(--primary);
}
.explanation-card .label { font-size: 12px; color: var(--primary); font-weight: 600; margin-bottom: 6px; }

/* ===== Buttons ===== */
.btn {
  display: block;
  width: 100%;
  padding: 14px;
  border: none;
  border-radius: 10px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  text-align: center;
}
.btn:active { transform: scale(0.98); }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:active { background: var(--primary-dark); }
.btn-success { background: var(--success); color: #fff; }
.btn-success:active { background: #389e0d; }
.btn-outline { background: #fff; color: var(--primary); border: 2px solid var(--primary); }
.btn-outline:active { background: var(--primary-light); }
.btn-danger { background: var(--error); color: #fff; }
.btn-warning { background: var(--warning); color: #fff; }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

.btn-group { display: flex; gap: 10px; padding: 0 12px; }
.btn-group .btn { flex: 1; }

.action-bar {
  position: sticky;
  bottom: 0;
  left: 0;
  right: 0;
  background: #fff;
  padding: 12px;
  box-shadow: 0 -2px 8px rgba(0,0,0,0.06);
  z-index: 50;
}

/* ===== Result Page ===== */
.result-hero {
  text-align: center;
  padding: 40px 20px 20px;
}
.result-hero .score-circle {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  margin: 0 auto 16px;
  border: 6px solid;
}
.result-hero .score-circle .score { font-size: 32px; font-weight: 700; }
.result-hero .score-circle .unit { font-size: 14px; }
.result-hero.pass .score-circle { border-color: var(--success); color: var(--success); }
.result-hero.fail .score-circle { border-color: var(--error); color: var(--error); }
.result-hero h2 { font-size: 20px; margin-bottom: 4px; }
.result-hero p { font-size: 13px; color: var(--text-hint); }

.result-stats {
  display: flex;
  justify-content: space-around;
  padding: 16px;
  background: #fff;
  margin: 0 12px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.result-stats .stat { text-align: center; }
.result-stats .stat .num { font-size: 22px; font-weight: 700; }
.result-stats .stat .label { font-size: 11px; color: var(--text-hint); }
.result-stats .stat.correct .num { color: var(--success); }
.result-stats .stat.wrong .num { color: var(--error); }
.result-stats .stat.skip .num { color: var(--text-hint); }

/* ===== Wrong Book ===== */
.wrong-book-empty {
  text-align: center;
  padding: 60px 20px;
  color: var(--text-hint);
}
.wrong-book-empty .icon { font-size: 48px; margin-bottom: 12px; }
.wrong-book-list { padding: 12px; }
.wrong-item {
  background: #fff;
  border-radius: var(--radius);
  padding: 16px;
  margin-bottom: 10px;
  box-shadow: var(--shadow);
}
.wrong-item .q-text { font-size: 14px; margin-bottom: 8px; }
.wrong-item .answer-row {
  display: flex;
  gap: 12px;
  font-size: 12px;
  margin-top: 6px;
}
.wrong-item .answer-row .your { color: var(--error); }
.wrong-item .answer-row .correct { color: var(--success); }
.wrong-item .actions { display: flex; gap: 8px; margin-top: 8px; }
.wrong-item .actions button {
  padding: 4px 12px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: #fff;
  font-size: 12px;
  cursor: pointer;
}

/* ===== Exam Setup ===== */
.exam-setup { padding: 16px 12px; }
.exam-info-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 20px 16px;
  box-shadow: var(--shadow);
  margin-bottom: 16px;
}
.exam-info-card h3 { font-size: 16px; margin-bottom: 12px; }
.exam-info-card .info-row {
  display: flex;
  justify-content: space-between;
  padding: 8px 0;
  border-bottom: 1px solid var(--border);
  font-size: 14px;
}
.exam-info-card .info-row:last-child { border-bottom: none; }
.exam-info-card .info-row .label { color: var(--text-secondary); }
.exam-info-card .info-row .value { font-weight: 600; }

/* ===== Timer ===== */
.exam-timer {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 14px;
  font-weight: 600;
}
.exam-timer .time { font-variant-numeric: tabular-nums; }
.exam-timer.warning .time { color: var(--error); }

/* ===== Group Practice ===== */
.group-setup { padding: 16px 12px; }
.input-group { margin-bottom: 14px; }
.input-group label { display: block; font-size: 13px; color: var(--text-secondary); margin-bottom: 6px; }
.input-group input, .input-group select {
  width: 100%;
  padding: 12px;
  border: 2px solid var(--border);
  border-radius: 10px;
  font-size: 15px;
  outline: none;
  transition: border-color 0.2s;
}
.input-group input:focus, .input-group select:focus { border-color: var(--primary); }

.share-card {
  background: var(--primary-light);
  border-radius: var(--radius);
  padding: 16px;
  margin: 16px 0;
  text-align: center;
}
.share-card .code {
  font-size: 28px;
  font-weight: 700;
  color: var(--primary);
  letter-spacing: 4px;
  margin: 8px 0;
}
.share-card .link {
  word-break: break-all;
  font-size: 12px;
  color: var(--text-secondary);
  background: #fff;
  padding: 8px;
  border-radius: 8px;
  margin-top: 8px;
}

/* ===== Toast ===== */
.toast {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background: rgba(0,0,0,0.75);
  color: #fff;
  padding: 12px 24px;
  border-radius: 8px;
  font-size: 14px;
  z-index: 9999;
  opacity: 0;
  transition: opacity 0.3s;
  pointer-events: none;
}
.toast.show { opacity: 1; }

/* ===== Misc ===== */
.section-title {
  font-size: 15px;
  font-weight: 600;
  padding: 12px 4px 8px;
  color: var(--text-secondary);
}
.empty-hint { text-align: center; padding: 40px 20px; color: var(--text-hint); font-size: 14px; }
.mb-12 { margin-bottom: 12px; }
.mt-12 { margin-top: 12px; }
.flex-between { display: flex; justify-content: space-between; align-items: center; }

/* Review answers in result */
.review-list { padding: 12px; }
.review-item {
  background: #fff;
  border-radius: var(--radius);
  padding: 16px;
  margin-bottom: 10px;
  box-shadow: var(--shadow);
}
.review-item .q-num { font-size: 12px; color: var(--text-hint); margin-bottom: 4px; }
.review-item .q-text { font-size: 14px; margin-bottom: 8px; }
.review-item .review-answer { font-size: 13px; margin-top: 4px; }
.review-item .review-answer.correct { color: var(--success); }
.review-item .review-answer.wrong { color: var(--error); }

/* Tab bar */
.tab-bar {
  display: flex;
  background: #fff;
  border-bottom: 2px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 50;
}
.tab-bar .tab {
  flex: 1;
  padding: 12px 8px;
  text-align: center;
  font-size: 13px;
  color: var(--text-hint);
  cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  transition: all 0.2s;
}
.tab-bar .tab.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
  font-weight: 600;
}

/* ===== Expiry Banner ===== */
.expiry-banner {
  margin: 8px 12px 0;
  padding: 8px 14px;
  border-radius: 8px;
  font-size: 12px;
  text-align: center;
  font-weight: 600;
}
.expiry-banner.normal {
  background: var(--success-bg);
  color: var(--success);
}
.expiry-banner.warning {
  background: var(--warning-bg);
  color: var(--warning);
}
.expiry-banner.urgent {
  background: var(--error-bg);
  color: var(--error);
}

/* ===== Expired View ===== */
.expired-hero {
  background: linear-gradient(135deg, #ff7875, #d4380d);
  color: #fff;
  padding: 60px 20px 40px;
  text-align: center;
}
.expired-hero .icon { font-size: 56px; margin-bottom: 12px; }
.expired-hero h2 { font-size: 22px; font-weight: 700; }
.expired-hero p { font-size: 14px; opacity: 0.85; margin-top: 6px; }
.expired-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 20px 16px;
  box-shadow: var(--shadow);
  margin: -20px 12px 16px;
  position: relative;
  z-index: 10;
}
.expired-card .info-row {
  display: flex;
  justify-content: space-between;
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
  font-size: 14px;
}
.expired-card .info-row:last-child { border-bottom: none; }
.expired-card .info-row .label { color: var(--text-secondary); }
.expired-card .info-row .value { font-weight: 600; }

/* ===== Login Modal ===== */
.modal-overlay {
  position: fixed; top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.5);
  display: flex; align-items: center; justify-content: center;
  z-index: 9999;
}
.modal-overlay[style*="display:none"] { display: none !important; }
.modal-box {
  background: #fff; border-radius: 12px; width: 90%; max-width: 380px;
  box-shadow: 0 8px 32px rgba(0,0,0,0.2);
  overflow: hidden;
}
.modal-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 16px 20px; border-bottom: 1px solid var(--border);
}
.modal-header h3 { font-size: 18px; color: var(--text-primary); }
.modal-close {
  background: none; border: none; font-size: 24px; color: var(--text-hint);
  cursor: pointer; padding: 0; line-height: 1;
}
.modal-close:hover { color: var(--text-primary); }
.modal-body { padding: 20px; }
.modal-body .input-group { margin-bottom: 0; }
.modal-body .input-group label { display: block; font-size: 13px; color: var(--text-secondary); margin-bottom: 6px; }
.modal-body .input-group input {
  width: 100%; padding: 10px 12px; border: 1px solid var(--border);
  border-radius: 8px; font-size: 15px; outline: none; transition: border-color 0.2s;
}
.modal-body .input-group input:focus { border-color: var(--primary); }
.modal-footer {
  display: flex; gap: 10px; justify-content: flex-end;
  padding: 12px 20px; border-top: 1px solid var(--border);
}
.modal-footer .btn { min-width: 80px; }

/* ===== 一键开考 / 模拟考房间 (2026-10-27) ===== */
body.wide { max-width: 1080px; }
.staff-bar { display:flex; align-items:center; gap:10px; margin:10px 12px 0; padding:12px 14px; background:#fff; border-radius:var(--radius); box-shadow:var(--shadow); cursor:pointer; border-left:4px solid var(--warning); }
.staff-bar .staff-icon { font-size:22px; }
.staff-bar .staff-text { flex:1; display:flex; flex-direction:column; line-height:1.35; }
.staff-bar .staff-text b { font-size:14px; color:var(--text-main); }
.staff-bar .staff-text i { font-style:normal; font-size:11px; color:var(--text-hint); }
.staff-bar .staff-arrow { color:var(--text-hint); font-size:20px; }
.room-panel { background:#fff; margin:12px; padding:20px 16px; border-radius:var(--radius); box-shadow:var(--shadow); text-align:center; }
.room-hero-icon { font-size:44px; line-height:1; }
.room-h2 { font-size:20px; font-weight:600; margin:8px 0; }
.room-desc { font-size:14px; color:var(--text-secondary); line-height:1.7; margin-bottom:14px; }
.room-hint { font-size:12px; color:var(--text-hint); margin-top:10px; }
.room-code-label { font-size:13px; color:var(--text-hint); letter-spacing:2px; }
.room-code { font-size:72px; font-weight:700; letter-spacing:12px; color:var(--primary-dark); line-height:1.1; margin:4px 0 10px; }
.room-qr { display:inline-block; padding:10px; background:#fff; border:1px solid var(--border); border-radius:8px; }
.room-url { font-size:13px; color:var(--text-secondary); word-break:break-all; margin:10px 0 4px; }
.room-meta { font-size:14px; color:var(--text-secondary); margin:10px 0 16px; }
.room-num { font-size:22px; color:var(--primary-dark); }
.room-code-mini { font-size:14px; color:var(--text-hint); letter-spacing:1px; }
.room-timer-big { font-size:60px; font-weight:700; color:var(--primary-dark); line-height:1.1; font-variant-numeric:tabular-nums; }
.room-timer-big.warn { color:var(--error); }
.room-stats-row { display:grid; grid-template-columns:repeat(4,1fr); gap:8px; margin:12px 0 16px; }
.room-stat { background:#f7f9fc; border-radius:8px; padding:10px 4px; font-size:12px; color:var(--text-hint); }
.room-stat span { display:block; font-size:20px; font-weight:600; color:var(--text-main); }
.board-table { width:100%; border-collapse:collapse; font-size:13px; margin:8px 0 16px; text-align:left; }
.board-table th { background:#f7f9fc; color:var(--text-secondary); font-weight:500; font-size:12px; }
.board-table th, .board-table td { padding:8px 6px; border-bottom:1px solid var(--border); }
.board-table b { color:var(--primary-dark); }
.btn-xl { width:100%; font-size:17px; padding:15px; border-radius:10px; margin-top:10px; }
.btn-block { width:100%; margin-top:8px; }
.room-waiting { padding:40px 16px; }
.wait-dot { width:14px; height:14px; border-radius:50%; background:var(--success); margin:0 auto 14px; animation:waitpulse 1.2s infinite; }
@keyframes waitpulse { 0%,100% { opacity:.35; transform:scale(.85); } 50% { opacity:1; transform:scale(1.15); } }