:root{
  --bg:#f5f7fa; --panel:#ffffff; --border:#e6e9ef; --text:#1f2937; --muted:#6b7280;
  --primary:#4f46e5; --primary-d:#4338ca;
  --ok:#16a34a; --ok-bg:#ecfdf5; --warn:#dc2626; --warn-bg:#fef2f2;
  --susp:#d97706; --susp-bg:#fffbeb;
  --shadow:0 1px 3px rgba(16,24,40,.06),0 1px 2px rgba(16,24,40,.04);
}
*{box-sizing:border-box}
body{margin:0;display:flex;min-height:100vh;background:var(--bg);color:var(--text);
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;}

/* Sidebar */
.sidebar{width:230px;background:var(--panel);border-right:1px solid var(--border);
  display:flex;flex-direction:column;padding:18px 14px;position:sticky;top:0;height:100vh;}
.brand{display:flex;gap:10px;align-items:center;padding:6px 6px 18px;}
.brand-logo{width:38px;height:38px;border-radius:10px;background:linear-gradient(135deg,#6366f1,#4f46e5);
  color:#fff;font-weight:700;display:grid;place-items:center;font-size:18px;}
.brand-name{font-weight:700;font-size:15px;}
.brand-sub{font-size:12px;color:var(--muted);}
.nav{display:flex;flex-direction:column;gap:4px;margin-top:8px;}
.nav-item{display:flex;align-items:center;gap:10px;padding:10px 12px;border-radius:9px;
  color:var(--muted);cursor:pointer;font-size:14px;text-decoration:none;user-select:none;}
.nav-item .ico{width:18px;text-align:center;opacity:.8;}
.nav-item:hover{background:#f3f4f6;color:var(--text);}
.nav-item.active{background:#eef2ff;color:var(--primary-d);font-weight:600;}
.side-foot{margin-top:auto;padding:8px 6px;}

/* Main */
.main{flex:1;display:flex;flex-direction:column;min-width:0;}
.topbar{display:flex;align-items:center;justify-content:space-between;
  padding:16px 26px;border-bottom:1px solid var(--border);background:var(--panel);}
.topbar h1{font-size:18px;margin:0;}
.top-actions{display:flex;align-items:center;gap:14px;}
.view{padding:22px 26px;}
.hidden{display:none!important;}

/* Buttons */
.btn{border:1px solid var(--border);background:#fff;color:var(--text);padding:8px 14px;
  border-radius:8px;cursor:pointer;font-size:13px;transition:.15s;}
.btn:hover{background:#f3f4f6;}
.btn-primary{background:var(--primary);border-color:var(--primary);color:#fff;}
.btn-primary:hover{background:var(--primary-d);}
.btn-ghost{background:transparent;}
.btn-mini{padding:5px 10px;font-size:12px;}
.btn-danger{color:var(--warn);border-color:#f3c9c9;}
.btn-accent{background:#0d9488;border-color:#0d9488;color:#fff;}
.btn-accent:hover{background:#0f766e;}

/* Badge */
.badge{padding:3px 9px;border-radius:20px;font-size:12px;font-weight:600;}
.badge-mock{background:var(--susp-bg);color:var(--susp);}
.badge-live{background:var(--ok-bg);color:var(--ok);}
.muted{color:var(--muted);font-size:13px;}

/* Cards */
.cards{display:grid;grid-template-columns:repeat(5,1fr);gap:16px;margin-bottom:18px;}
.card{background:var(--panel);border:1px solid var(--border);border-radius:12px;
  padding:18px;box-shadow:var(--shadow);}
.stat .stat-label{font-size:13px;color:var(--muted);}
.stat .stat-value{font-size:30px;font-weight:700;margin-top:8px;}
.stat.ok .stat-value{color:var(--ok);}
.stat.warn .stat-value{color:var(--warn);}
.stat.susp .stat-value{color:var(--susp);}
.chart-card{grid-column:span 2;}
.cards:has(.chart-card){grid-template-columns:1fr 1fr;}
.card-title{font-size:14px;font-weight:600;margin-bottom:12px;}
.chart-card canvas{max-height:260px;}

/* Toolbar */
.toolbar{display:flex;gap:10px;align-items:center;margin-bottom:14px;flex-wrap:wrap;}
.toolbar select,.toolbar input{padding:8px 10px;border:1px solid var(--border);
  border-radius:8px;font-size:13px;background:#fff;color:var(--text);}
.toolbar input{min-width:200px;}

/* Summary Cards（学员明细页汇总） */
.summary-cards{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;margin-bottom:18px;}
.summary-card{background:var(--panel);border:1px solid var(--border);border-radius:12px;
  padding:16px 18px;box-shadow:var(--shadow);}
.summary-card .summary-label{font-size:12.5px;color:var(--muted);margin-bottom:6px;}
.summary-card .summary-value{font-size:28px;font-weight:700;color:var(--text);}
.summary-card .summary-value.ok{color:var(--ok);}
.summary-card .summary-value.highlight{color:var(--primary);}

/* Table */
.table-wrap{background:var(--panel);border:1px solid var(--border);border-radius:12px;
  overflow:hidden;box-shadow:var(--shadow);}
table{width:100%;border-collapse:collapse;font-size:13.5px;}
thead th{text-align:left;padding:12px 16px;background:#f9fafb;color:var(--muted);
  font-weight:600;border-bottom:1px solid var(--border);white-space:nowrap;}
tbody td{padding:11px 16px;border-bottom:1px solid #f1f3f7;}
tbody tr:last-child td{border-bottom:none;}
tbody tr:hover{background:#fafbff;}
.pill{padding:3px 10px;border-radius:20px;font-size:12px;font-weight:600;display:inline-block;}
.pill.in_group{background:var(--ok-bg);color:var(--ok);}
.pill.missing{background:var(--warn-bg);color:var(--warn);}
.pill.suspect{background:var(--susp-bg);color:var(--susp);}
.pill.unmapped{background:#eef2f7;color:#64748b;}
.empty{padding:40px;text-align:center;color:var(--muted);}

/* 数值列右对齐 */
.col-num{text-align:right;white-space:nowrap;}
.col-toggle{width:34px;text-align:center;color:var(--muted);user-select:none;}
.col-teacher{white-space:nowrap;font-size:12px;color:var(--muted);max-width:120px;overflow:hidden;text-overflow:ellipsis;}

/* 班级分组行（可展开） */
.class-row{cursor:pointer;background:#fbfcfe;font-size:14px;}
.class-row:hover{background:#f1f5ff;}
.class-row .class-name{color:var(--text);}
.class-row .teacher-tag{font-size:12px;color:var(--primary);font-weight:400;margin-left:6px;
  background:#eef2ff;padding:1px 8px;border-radius:10px;white-space:nowrap;}
.class-row .toggle-ico{display:inline-block;font-size:11px;transition:transform .15s;color:var(--primary);}
.detail-row{background:#fcfdff;}
.detail-inner{padding:4px 0 8px 30px;}

/* 展开后的学员明细表 */
.detail-table{width:100%;border-collapse:collapse;font-size:13px;margin-top:2px;}
.detail-table thead th{background:#f3f5fa;color:var(--muted);font-weight:600;
  padding:8px 14px;border-bottom:1px solid var(--border);text-align:left;}
.detail-table tbody td{padding:8px 14px;border-bottom:1px solid #f4f6fa;}
.detail-table tbody tr:last-child td{border-bottom:none;}
.detail-table tbody tr:hover{background:#f7f9ff;}

/* 班级行入群率徽标 */
.rate-pill{padding:2px 9px;border-radius:20px;font-size:12px;font-weight:700;display:inline-block;}
.rate-pill.high{background:var(--ok-bg);color:var(--ok);}
.rate-pill.mid{background:var(--susp-bg);color:var(--susp);}
.rate-pill.low{background:var(--warn-bg);color:var(--warn);}

/* Modal */
.modal{position:fixed;inset:0;background:rgba(17,24,39,.45);display:grid;place-items:center;z-index:50;}
.modal-box{background:#fff;border-radius:14px;padding:24px;width:380px;box-shadow:0 20px 40px rgba(0,0,0,.2);}
.modal-box h3{margin:0 0 16px;}
.modal-box label{display:block;font-size:13px;color:var(--muted);margin-bottom:14px;}
.modal-box label.row{display:flex;align-items:center;gap:8px;color:var(--text);}
.modal-box select{width:100%;margin-top:6px;padding:9px 10px;border:1px solid var(--border);border-radius:8px;font-size:14px;}
.modal-actions{display:flex;justify-content:flex-end;gap:10px;margin-top:8px;}

/* Toast */
.toast{position:fixed;bottom:26px;left:50%;transform:translateX(-50%);
  background:#111827;color:#fff;padding:11px 20px;border-radius:10px;font-size:13.5px;z-index:99;box-shadow:0 8px 24px rgba(0,0,0,.25);}

@media(max-width:900px){.cards{grid-template-columns:1fr 1fr;}.chart-card{grid-column:span 2;}}

/* ============ 学员当前错误群 ============ */
.summary-card .summary-value.danger{color:var(--warn);}
.toolbar label.chk{display:flex;align-items:center;gap:6px;font-size:13px;color:var(--muted);cursor:pointer;margin:0;}
.toolbar label.chk input{width:auto;}

.wg-list{display:flex;flex-direction:column;gap:12px;}
.wg-card{background:var(--panel);border:1px solid var(--border);border-radius:12px;
  box-shadow:var(--shadow);overflow:hidden;}
.wg-card-head{display:flex;align-items:center;gap:12px;padding:14px 16px;cursor:pointer;
  border-left:4px solid transparent;transition:.15s;}
.wg-card-head:hover{background:#fafbff;}
.wg-card-head.has-wrong{border-left-color:var(--warn);background:var(--warn-bg);}
.wg-avatar{width:36px;height:36px;border-radius:50%;background:linear-gradient(135deg,#818cf8,#4f46e5);
  color:#fff;font-weight:700;display:grid;place-items:center;font-size:16px;flex-shrink:0;}
.wg-info{flex:1;min-width:0;}
.wg-name{font-weight:700;font-size:15px;}
.wg-correct{font-size:12.5px;color:var(--muted);margin-top:2px;
  white-space:nowrap;overflow:hidden;text-overflow:ellipsis;}
.wg-badge{padding:4px 12px;border-radius:20px;font-size:12.5px;font-weight:700;white-space:nowrap;}
.badge-wrong{background:var(--warn-bg);color:var(--warn);}
.badge-ok{background:var(--ok-bg);color:var(--ok);}
.wg-card-head .toggle-ico{color:var(--primary);font-size:12px;width:16px;text-align:center;}

.wg-detail{padding:6px 16px 14px 64px;border-top:1px solid #f1f3f7;background:#fcfdff;}
.wg-group-item{display:flex;align-items:center;gap:10px;padding:9px 12px;border-radius:9px;
  margin-top:6px;background:#fff;border:1px solid var(--border);}
.wg-group-item.wg-wrong{border-color:#f3c9c9;background:var(--warn-bg);}
.wg-group-item .dot{width:9px;height:9px;border-radius:50%;flex-shrink:0;}
.dot-ok{background:var(--ok);}
.dot-wrong{background:var(--warn);}
.wg-group-main{flex:1;min-width:0;}
.wg-gname{font-weight:600;font-size:13.5px;}
.wg-cname{font-size:12px;color:var(--muted);margin-top:1px;}
/* 进错/正确 徽标（复用 .pill） */
.pill.ok{background:var(--ok-bg);color:var(--ok);}
.pill.wrong{background:var(--warn-bg);color:var(--warn);}

/* ============ 登录遮罩 ============ */
.login-overlay{position:fixed;inset:0;background:linear-gradient(135deg,#4f46e5,#7c3aed);
  display:grid;place-items:center;z-index:100;}
.login-card{background:#fff;border-radius:18px;padding:34px 32px;width:340px;
  box-shadow:0 24px 50px rgba(0,0,0,.28);text-align:center;}
.login-card h2{margin:14px 0 4px;font-size:20px;}
.login-card .muted{margin-bottom:18px;display:block;}
.login-logo{width:54px;height:54px;border-radius:14px;margin:0 auto;
  background:linear-gradient(135deg,#6366f1,#4f46e5);color:#fff;font-weight:700;
  display:grid;place-items:center;font-size:26px;}
.login-card label{display:block;text-align:left;font-size:13px;color:var(--muted);margin-bottom:14px;}
.login-card input{width:100%;margin-top:6px;padding:10px 12px;border:1px solid var(--border);
  border-radius:9px;font-size:14px;background:#fff;color:var(--text);box-sizing:border-box;}
.login-card input:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px #eef2ff;}
.btn-block{width:100%;padding:11px;font-size:14px;margin-top:4px;}
.login-err{color:var(--warn);font-size:13px;margin-top:12px;min-height:18px;}

/* ============ 用户菜单 ============ */
.user-chip{display:flex;align-items:center;gap:10px;font-size:13px;color:var(--text);
  background:#f3f4f6;padding:5px 6px 5px 12px;border-radius:20px;}
#userName{font-weight:600;}

/* ============ 账号管理 ============ */
.form-card{max-width:720px;margin-bottom:18px;}
.form-card h3{margin:0 0 16px;font-size:16px;}
.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px 18px;}
.form-grid label{display:block;font-size:13px;color:var(--muted);margin:0;}
.form-grid label.full{grid-column:span 2;}
.form-grid input,.form-grid select{width:100%;margin-top:6px;padding:9px 11px;
  border:1px solid var(--border);border-radius:8px;font-size:14px;background:#fff;color:var(--text);
  box-sizing:border-box;}
.form-grid input:focus,.form-grid select:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px #eef2ff;}

.share-card{max-width:560px;margin-bottom:18px;border-color:#bbf7d0;background:#f0fdf4;}
.share-card h3{margin:0 0 14px;font-size:15px;color:var(--ok);}
.share-body{font-size:14px;}
.share-line{display:flex;align-items:center;gap:10px;padding:8px 0;border-bottom:1px dashed #e2e8f0;}
.share-line:last-of-type{border-bottom:none;}
.share-k{width:64px;color:var(--muted);flex-shrink:0;}
.share-line code{background:#111827;color:#e5e7eb;padding:6px 12px;border-radius:7px;
  font-size:13.5px;flex:1;word-break:break-all;font-family:ui-monospace,SFMono-Regular,Menlo,monospace;}
.share-tip{margin-top:12px;font-size:12.5px;color:var(--susp);background:var(--susp-bg);
  padding:9px 12px;border-radius:8px;line-height:1.5;}

#accountTableWrap{margin-top:6px;}
#accountTable tbody td .btn{margin-right:4px;}
#accountTable tbody td .btn:last-child{margin-right:0;}

/* 使用说明备注框 */
.usage-note{
  background:#fffbeb;border:1px solid #fde68a;border-left:4px solid #f59e0b;
  border-radius:10px;padding:12px 16px;margin-bottom:16px;color:#92400e;
}
.usage-note-title{font-weight:700;margin-bottom:6px;font-size:14px;color:#b45309;}
.usage-note ol{margin:0;padding-left:20px;}
.usage-note li{line-height:1.7;font-size:13px;}
.usage-note b{color:#7c2d12;}