/* exam 在线考试系统 — 全局样式 */
:root {
  --primary: #2f6fed;
  --primary-dark: #1f5ad8;
  --bg: #f2f4f9;
  --card: #ffffff;
  --text: #1f2733;
  --muted: #7a8699;
  --border: #e3e8f0;
  --success: #18a058;
  --warning: #f0a020;
  --danger: #d03050;
  --radius: 10px;
  --shadow: 0 2px 10px rgba(31, 45, 90, .06);
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  background: var(--bg); color: var(--text); font-size: 14px; line-height: 1.6;
}
pre, .pre-wrap { white-space: pre-wrap; word-break: break-word; font-family: inherit; }

/* ---------- 布局 ---------- */
.topnav {
  position: sticky; top: 0; z-index: 50; display: flex; align-items: center; gap: 4px;
  background: #fff; border-bottom: 1px solid var(--border); padding: 0 20px; height: 56px;
}
.topnav .brand { font-size: 17px; font-weight: 700; color: var(--primary); margin-right: 24px; }
.topnav a {
  color: var(--text); text-decoration: none; padding: 6px 12px; border-radius: 8px; font-size: 14px;
}
.topnav a:hover { background: #eef3ff; }
.topnav a.active { color: var(--primary); background: #eaf1ff; font-weight: 600; }
.topnav .spacer { flex: 1; }
.topnav .who { color: var(--muted); font-size: 13px; margin-right: 10px; }
.container { max-width: 1200px; margin: 24px auto; padding: 0 20px; }
.card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow); padding: 20px; margin-bottom: 16px;
}
.card h3 { font-size: 16px; margin-bottom: 14px; }
.page-title { font-size: 20px; font-weight: 700; margin-bottom: 16px; }
.muted { color: var(--muted); }
.row { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }
.grid { display: grid; gap: 16px; }
.grid-4 { grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); }
.stat-card { text-align: center; padding: 18px; }
.stat-card .num { font-size: 30px; font-weight: 700; color: var(--primary); }
.stat-card .label { color: var(--muted); margin-top: 4px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-block; border: 1px solid var(--border); background: #fff; color: var(--text);
  padding: 7px 16px; border-radius: 8px; cursor: pointer; font-size: 14px; line-height: 1.4;
  transition: all .15s;
}
.btn:hover { border-color: var(--primary); color: var(--primary); }
.btn-primary { background: var(--primary); border-color: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); color: #fff; }
.btn-danger { color: var(--danger); border-color: #f3c2cf; }
.btn-danger:hover { background: #fff0f3; border-color: var(--danger); color: var(--danger); }
.btn-sm { padding: 3px 10px; font-size: 13px; }
.btn:disabled { opacity: .5; cursor: not-allowed; }
.btn-lg { padding: 10px 28px; font-size: 15px; }

/* ---------- 表格 ---------- */
table.tbl { width: 100%; border-collapse: collapse; font-size: 14px; }
.tbl th, .tbl td { padding: 10px 12px; border-bottom: 1px solid var(--border); text-align: left; }
.tbl th { background: #f7f9fd; color: var(--muted); font-weight: 600; white-space: nowrap; }
.tbl tr:hover td { background: #fafbff; }
.tbl .actions { white-space: nowrap; }
.tbl .actions .btn { margin-right: 6px; }

/* ---------- 表单 ---------- */
.form-item { margin-bottom: 14px; }
.form-item label { display: block; margin-bottom: 5px; font-weight: 600; font-size: 13px; }
.form-item input[type=text], .form-item input[type=password], .form-item input[type=number],
.form-item input[type=datetime-local], .form-item select, .form-item textarea {
  width: 100%; padding: 8px 12px; border: 1px solid var(--border); border-radius: 8px;
  font-size: 14px; font-family: inherit; background: #fff;
}
.form-item textarea { min-height: 90px; resize: vertical; }
.form-item input:focus, .form-item select:focus, .form-item textarea:focus {
  outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(47, 111, 237, .12);
}
.form-hint { font-size: 12px; color: var(--muted); margin-top: 4px; }

/* ---------- 徽章/标签 ---------- */
.badge { display: inline-block; padding: 2px 10px; border-radius: 999px; font-size: 12px; font-weight: 600; }
.badge-green { background: #e7f6ee; color: var(--success); }
.badge-red { background: #fdebef; color: var(--danger); }
.badge-orange { background: #fdf3e3; color: #c47d0e; }
.badge-blue { background: #eaf1ff; color: var(--primary); }
.badge-gray { background: #eef0f4; color: var(--muted); }

/* ---------- 登录页 ---------- */
.login-wrap { min-height: 100vh; display: flex; align-items: center; justify-content: center;
  background: linear-gradient(135deg, #2f6fed 0%, #6a9bff 100%); padding: 20px; }
.login-card { width: 400px; max-width: 94vw; background: #fff; border-radius: 14px;
  box-shadow: 0 12px 40px rgba(20, 40, 100, .25); padding: 34px 32px; }
.login-card h1 { font-size: 22px; text-align: center; color: var(--primary); margin-bottom: 4px; }
.login-card .sub { text-align: center; color: var(--muted); font-size: 13px; margin-bottom: 22px; }
.login-tabs { display: flex; border-bottom: 1px solid var(--border); margin-bottom: 20px; }
.login-tabs div { flex: 1; text-align: center; padding: 10px; cursor: pointer; color: var(--muted);
  border-bottom: 2px solid transparent; margin-bottom: -1px; }
.login-tabs div.active { color: var(--primary); border-bottom-color: var(--primary); font-weight: 600; }

/* ---------- 弹窗/提示 ---------- */
.modal-mask { position: fixed; inset: 0; background: rgba(15, 25, 50, .45); z-index: 100;
  display: flex; align-items: flex-start; justify-content: center; padding: 40px 16px; overflow-y: auto; }
.modal { background: #fff; border-radius: 12px; width: 560px; max-width: 96vw; padding: 22px 24px;
  box-shadow: 0 16px 50px rgba(0, 0, 0, .2); }
.modal.wide { width: 860px; }
.modal h3 { margin-bottom: 16px; font-size: 17px; }
.modal .modal-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 18px; }
#toast-root { position: fixed; top: 70px; left: 50%; transform: translateX(-50%); z-index: 200; }
.toast { background: #222c3f; color: #fff; padding: 10px 22px; border-radius: 8px; margin-bottom: 10px;
  box-shadow: 0 6px 20px rgba(0, 0, 0, .25); animation: fadein .2s; font-size: 14px; }
.toast.success { background: var(--success); }
.toast.error { background: var(--danger); }
.toast.warning { background: var(--warning); }
@keyframes fadein { from { opacity: 0; transform: translateY(-8px); } to { opacity: 1; } }

/* ---------- 考试页 ---------- */
.exam-header { position: sticky; top: 0; z-index: 60; background: #fff; border-bottom: 1px solid var(--border);
  padding: 10px 20px; display: flex; align-items: center; gap: 16px; flex-wrap: wrap; }
.exam-header .title { font-size: 16px; font-weight: 700; }
.timer { font-size: 20px; font-weight: 700; font-variant-numeric: tabular-nums; color: var(--primary);
  background: #eaf1ff; padding: 4px 16px; border-radius: 999px; }
.timer.danger { color: var(--danger); background: #fdebef; }
.save-state { color: var(--muted); font-size: 13px; }
.exam-body { display: flex; gap: 18px; max-width: 1280px; margin: 18px auto; padding: 0 16px;
  align-items: flex-start; }
.qnav { width: 208px; flex-shrink: 0; position: sticky; top: 76px; background: #fff;
  border: 1px solid var(--border); border-radius: var(--radius); padding: 14px; }
.qnav .legend { font-size: 12px; color: var(--muted); margin-bottom: 10px; display: flex; gap: 10px; flex-wrap: wrap; }
.qnav .legend i { display: inline-block; width: 12px; height: 12px; border-radius: 3px; margin-right: 4px;
  vertical-align: -1px; }
.qnav-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 6px; }
.qnav-grid button { aspect-ratio: 1; border: 1px solid var(--border); background: #fff; border-radius: 6px;
  cursor: pointer; font-size: 13px; }
.qnav-grid button.answered { background: var(--success); border-color: var(--success); color: #fff; }
.qnav-grid button.marked { background: var(--warning); border-color: var(--warning); color: #fff; }
.qnav-grid button.marked.answered { background: linear-gradient(135deg, var(--success) 50%, var(--warning) 50%); }
.qnav-grid button.current { outline: 2px solid var(--primary); }
.exam-main { flex: 1; min-width: 0; }
.q-card { background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  padding: 18px 20px; margin-bottom: 14px; }
.q-card .q-head { display: flex; gap: 10px; align-items: center; margin-bottom: 8px; }
.q-card .q-no { font-weight: 700; font-size: 15px; }
.q-card .q-content { margin: 6px 0 12px; font-size: 15px; }
.opt { display: block; padding: 8px 12px; border: 1px solid var(--border); border-radius: 8px;
  margin-bottom: 8px; cursor: pointer; }
.opt:hover { border-color: var(--primary); background: #f7faff; }
.opt input { margin-right: 8px; }
.opt.correct { border-color: var(--success); background: #e7f6ee; }
.opt.wrong { border-color: var(--danger); background: #fdebef; }
.essay-input { width: 100%; min-height: 140px; padding: 10px 12px; border: 1px solid var(--border);
  border-radius: 8px; font-size: 14px; font-family: inherit; resize: vertical; }
.mark-btn { font-size: 12px; color: var(--muted); border: 1px solid var(--border); background: #fff;
  border-radius: 6px; padding: 2px 8px; cursor: pointer; }
.mark-btn.on { color: var(--warning); border-color: var(--warning); background: #fdf3e3; }

/* ---------- 阅卷 ---------- */
.grading-card { border: 1px solid var(--border); border-radius: var(--radius); padding: 16px;
  margin-bottom: 14px; background: #fff; }
.grading-card .anon { font-weight: 700; color: var(--primary); }
.progress-bar { height: 8px; background: #eef0f4; border-radius: 999px; overflow: hidden; }
.progress-bar i { display: block; height: 100%; background: var(--primary); }

/* ---------- 导入向导 ---------- */
.import-errors { max-height: 260px; overflow-y: auto; }
.cand-picker { max-height: 300px; overflow-y: auto; border: 1px solid var(--border); border-radius: 8px; padding: 10px; }
.cand-picker label { display: inline-flex; gap: 6px; align-items: center; width: 48%; margin: 3px 0; font-weight: 400; }

.score-big { font-size: 34px; font-weight: 700; color: var(--primary); }
@media (max-width: 900px) {
  .exam-body { flex-direction: column; }
  .qnav { width: 100%; position: static; }
  .topnav { overflow-x: auto; }
}