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

:root {
  --gold: #b8862d;
  --gold-light: #d4a847;
  --gold-dark: #8a6920;
  --brown: #6b4f3a;
  --brown-dark: #3c2a1e;
  --brown-light: #8c6f56;
  --bg: #f5f0ea;
  --bg-card: #ffffff;
  --text: #2c2416;
  --text-soft: #7a6e60;
  --border: #e5dccd;
  --success: #4a7c59;
  --danger: #b5443a;
  --warning: #c08a3e;
  --shadow: 0 1px 4px rgba(60, 42, 30, 0.08);
  --shadow-lg: 0 4px 16px rgba(60, 42, 30, 0.12);
  --radius: 6px;
}

html, body {
  font-family: "Microsoft YaHei", "微软雅黑", "PingFang SC", "Hiragino Sans GB", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
}

#app { min-height: 100vh; }

.container {
  max-width: 720px;
  margin: 0 auto;
  padding: 20px;
}

.container-wide {
  max-width: 1100px;
  margin: 0 auto;
  padding: 20px;
}

.card {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
  margin-bottom: 16px;
  border: 1px solid var(--border);
}

h1, h2, h3 { color: var(--brown-dark); margin-bottom: 12px; font-weight: 600; }
h1 { font-size: 22px; letter-spacing: 2px; }
h2 { font-size: 18px; letter-spacing: 1px; }
h3 { font-size: 15px; }

.text-soft { color: var(--text-soft); font-size: 14px; }
.text-success { color: var(--success); }
.text-danger { color: var(--danger); }
.text-warning { color: var(--warning); }
.text-center { text-align: center; }
.mb-1 { margin-bottom: 8px; }
.mb-2 { margin-bottom: 16px; }
.mb-3 { margin-bottom: 24px; }
.mt-1 { margin-top: 8px; }
.mt-2 { margin-top: 16px; }
.mt-3 { margin-top: 24px; }

.btn {
  display: inline-block;
  padding: 10px 24px;
  background: var(--gold);
  color: #fff;
  border: none;
  border-radius: var(--radius);
  font-size: 15px;
  cursor: pointer;
  transition: all 0.2s;
  text-decoration: none;
  letter-spacing: 1px;
}
.btn:hover { background: var(--gold-dark); }
.btn:disabled { background: #ccc; cursor: not-allowed; }
.btn-block { display: block; width: 100%; }
.btn-secondary { background: #fff; color: var(--brown); border: 1px solid var(--brown); }
.btn-secondary:hover { background: var(--brown); color: #fff; }
.btn-danger { background: var(--danger); }
.btn-sm { padding: 6px 14px; font-size: 13px; }
.btn-row { display: flex; gap: 8px; flex-wrap: wrap; }

input, select, textarea {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 15px;
  background: #fff;
  outline: none;
  transition: border-color 0.2s;
}
input:focus, select:focus, textarea:focus {
  border-color: var(--gold);
}
.form-row { margin-bottom: 14px; }
.form-row label {
  display: block;
  font-size: 14px;
  margin-bottom: 6px;
  color: var(--text);
  letter-spacing: 0.5px;
}

.header {
  background: linear-gradient(135deg, var(--brown-dark), var(--brown));
  color: #fff;
  padding: 28px 16px 24px;
  text-align: center;
  position: relative;
}
.header:after {
  content: '';
  display: block;
  width: 40px;
  height: 2px;
  background: var(--gold);
  margin: 10px auto 0;
}
.header h1 { color: #fff; margin: 0; font-size: 20px; letter-spacing: 4px; }
.header .sub { font-size: 13px; opacity: 0.85; margin-top: 6px; letter-spacing: 1px; }
.header .sys-logo {
  font-size: 28px;
  color: var(--gold);
  margin-bottom: 4px;
  display: block;
}

.timer {
  position: fixed;
  top: 12px;
  right: 12px;
  background: var(--brown-dark);
  color: #fff;
  padding: 6px 16px;
  border-radius: 4px;
  font-weight: bold;
  font-size: 14px;
  box-shadow: var(--shadow-lg);
  z-index: 100;
  letter-spacing: 1px;
}
.timer.warning { background: var(--warning); }
.timer.danger { background: var(--danger); }

.question {
  margin-bottom: 24px;
  padding: 16px 20px;
  background: #faf7f2;
  border-radius: var(--radius);
  border-left: 3px solid var(--gold);
}
.question-title {
  font-weight: 600;
  margin-bottom: 12px;
  font-size: 15px;
  line-height: 1.7;
}
.question-meta { font-size: 12px; color: var(--text-soft); margin-bottom: 8px; }

.option {
  display: flex;
  align-items: flex-start;
  padding: 10px 14px;
  margin-bottom: 8px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.15s;
}
.option:hover {
  border-color: var(--gold-light);
  background: #faf7f2;
  box-shadow: 0 1px 4px rgba(184, 134, 45, 0.08);
}
.option.selected { border-color: var(--gold); background: #f5ede0; }
.option input { width: auto; margin-right: 10px; margin-top: 5px; flex-shrink: 0; accent-color: var(--gold); }
.option-label { flex: 1; }

.nav {
  display: flex;
  gap: 6px;
  padding: 12px;
  background: var(--bg-card);
  border-radius: var(--radius);
  margin-bottom: 16px;
  overflow-x: auto;
  scroll-behavior: smooth;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}
.nav button {
  flex-shrink: 0;
  min-width: 34px;
  height: 34px;
  border-radius: 4px;
  border: 1px solid var(--border);
  background: #fff;
  cursor: pointer;
  font-size: 13px;
  color: var(--text);
  transition: all 0.15s;
}
.nav button.answered { background: var(--success); color: #fff; border-color: var(--success); }
.nav button.current { background: var(--gold); color: #fff; border-color: var(--gold); }

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}
th, td {
  padding: 10px 8px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}
th { background: #f5f0ea; font-weight: 600; color: var(--text-soft); font-size: 13px; letter-spacing: 0.5px; }
tr:hover td { background: #faf7f2; }

.tag {
  display: inline-block;
  padding: 2px 10px;
  border-radius: 3px;
  font-size: 12px;
  background: var(--border);
  color: var(--text);
  letter-spacing: 0.5px;
}
.tag.success { background: #d4e8db; color: var(--success); }
.tag.danger { background: #f5dad7; color: var(--danger); }
.tag.warning { background: #f5e6c8; color: var(--warning); }

.toast {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background: var(--brown-dark);
  color: #fff;
  padding: 16px 28px;
  border-radius: var(--radius);
  z-index: 1000;
  font-size: 14px;
  box-shadow: var(--shadow-lg);
  letter-spacing: 1px;
}

.result-summary {
  text-align: center;
  padding: 32px 16px;
}
.score-circle {
  display: inline-block;
  width: 120px;
  height: 120px;
  border-radius: 50%;
  background: var(--gold);
  color: #fff;
  line-height: 120px;
  font-size: 32px;
  font-weight: bold;
  margin: 16px auto;
  box-shadow: 0 2px 12px rgba(184, 134, 45, 0.3);
}
.score-circle.pass {
  background: var(--success);
  box-shadow: 0 2px 12px rgba(74, 124, 89, 0.3);
}
.score-circle.fail {
  background: var(--danger);
  box-shadow: 0 2px 12px rgba(181, 68, 58, 0.3);
}

.detail-row {
  padding: 12px 16px;
  border-radius: var(--radius);
  margin-bottom: 8px;
}
.detail-row.correct { background: #e8f3ec; border-left: 3px solid var(--success); }
.detail-row.wrong { background: #f9e6e3; border-left: 3px solid var(--danger); }
.detail-row .q { font-weight: 600; margin-bottom: 4px; font-size: 14px; }
.detail-row .a { font-size: 13px; color: var(--text-soft); }

.admin-nav {
  display: flex;
  gap: 4px;
  background: var(--bg-card);
  padding: 8px;
  border-radius: var(--radius);
  margin-bottom: 16px;
  overflow-x: auto;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}
.admin-nav button {
  flex-shrink: 0;
  padding: 8px 16px;
  border: none;
  background: transparent;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 14px;
  color: var(--text-soft);
  transition: all 0.15s;
  letter-spacing: 0.5px;
}
.admin-nav button.active { background: var(--gold); color: #fff; }
.admin-nav button:not(.active):hover { background: #f5f0ea; }

.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 12px;
  margin-bottom: 16px;
}
.stat-card {
  background: var(--bg-card);
  padding: 16px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  text-align: center;
}
.stat-card .v {
  font-size: 28px;
  font-weight: bold;
  color: var(--gold);
}
.stat-card .l { font-size: 13px; color: var(--text-soft); margin-top: 4px; }

.modal-mask {
  position: fixed; inset: 0;
  background: rgba(60, 42, 30, 0.5);
  display: flex; align-items: center; justify-content: center;
  z-index: 1000;
  padding: 16px;
}
.modal {
  background: #fff;
  border-radius: var(--radius);
  padding: 28px;
  width: 100%;
  max-width: 560px;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: 0 8px 32px rgba(60, 42, 30, 0.2);
}

.checkbox-list label {
  display: flex;
  align-items: center;
  padding: 6px 0;
  cursor: pointer;
}
.checkbox-list input { width: auto; margin-right: 8px; accent-color: var(--gold); }

.test-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}

.test-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px 20px;
  cursor: pointer;
  transition: all 0.2s;
  text-align: center;
}
.test-card:hover {
  border-color: var(--gold);
  box-shadow: 0 4px 20px rgba(184, 134, 45, 0.15);
  transform: translateY(-2px);
}
.test-card-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--brown-dark);
  margin-bottom: 8px;
  letter-spacing: 1px;
}
.test-card-desc {
  font-size: 13px;
  color: var(--text-soft);
  margin-bottom: 12px;
  line-height: 1.6;
}
.test-card-info {
  display: flex;
  justify-content: center;
  gap: 12px;
  font-size: 12px;
  color: var(--text-soft);
}

.student-id-badge {
  display: inline-block;
  background: linear-gradient(135deg, var(--gold), var(--gold-dark));
  color: #fff;
  padding: 8px 24px;
  border-radius: 4px;
  font-size: 16px;
  margin-bottom: 16px;
  letter-spacing: 1px;
}
.student-id-badge span { opacity: 0.9; }
.student-id-badge b { font-size: 24px; letter-spacing: 3px; }

.footer {
  background: var(--brown-dark);
  color: rgba(255,255,255,0.8);
  text-align: center;
  padding: 20px 16px;
  font-size: 12px;
  letter-spacing: 1px;
  margin-top: 40px;
}
.footer a { color: var(--gold-light); text-decoration: none; }

@media (max-width: 600px) {
  .container, .container-wide { padding: 12px; }
  .card { padding: 16px; }
  h1 { font-size: 18px; }
  .timer { font-size: 12px; padding: 6px 12px; }
  .test-grid { grid-template-columns: 1fr; }
}