/* ============================================================
   CTL 刷题 · 教师/管理端  —  科技感（深色玻璃拟态 + 霓虹）
   配色：深空蓝底 + 霓虹青/电蓝 + 微紫
   字体：系统清晰黑体（PingFang SC / Microsoft YaHei）
   类名与 admin.js 完全一致，仅做视觉重做
   ============================================================ */

:root{
  --bg:#070b1c;
  --bg2:#0c1430;
  --card:rgba(18,26,54,0.72);
  --card-solid:#101833;
  --text:#e7ecff;
  --muted:#8fa0c8;
  --primary:#22d3ee;
  --primary-dark:#0ea5b7;
  --primary-2:#6a8bff;
  --correct:#23e08a;
  --correct-bg:rgba(35,224,138,0.12);
  --wrong:#ff5d8f;
  --wrong-bg:rgba(255,93,143,0.12);
  --warn:#ffb84d;
  --border:rgba(120,150,220,0.18);
  --grid:rgba(90,140,255,0.10);
  --glow:0 0 18px rgba(34,211,238,0.35);
  --shadow:0 10px 30px rgba(0,0,0,0.45);
}
*{box-sizing:border-box;}
html,body{margin:0;padding:0;}
body{
  background:
    radial-gradient(1100px 700px at 85% -10%, rgba(34,211,238,0.10), transparent 55%),
    radial-gradient(900px 600px at 0% 100%, rgba(106,139,255,0.12), transparent 55%),
    linear-gradient(160deg, var(--bg) 0%, var(--bg2) 100%);
  background-attachment:fixed;
  color:var(--text);
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;
  font-size:14px;min-height:100vh;
}
/* 科技网格背景 */
body::before{
  content:"";position:fixed;inset:0;z-index:0;pointer-events:none;
  background-image:linear-gradient(var(--grid) 1px,transparent 1px),linear-gradient(90deg,var(--grid) 1px,transparent 1px);
  background-size:42px 42px;
  mask-image:radial-gradient(circle at 50% 30%, #000 0%, transparent 80%);
  -webkit-mask-image:radial-gradient(circle at 50% 30%, #000 0%, transparent 80%);
}
a{color:inherit;}

/* ================= 登录 ================= */
.login-mask{
  position:fixed;inset:0;display:flex;align-items:center;justify-content:center;padding:20px;z-index:100;
  background:
    radial-gradient(1000px 600px at 80% -10%, rgba(34,211,238,0.12), transparent 55%),
    radial-gradient(800px 500px at 0% 100%, rgba(106,139,255,0.14), transparent 55%),
    linear-gradient(160deg, var(--bg) 0%, var(--bg2) 100%);
}
.login-mask::before{
  content:"";position:absolute;inset:0;
  background-image:linear-gradient(var(--grid) 1px,transparent 1px),linear-gradient(90deg,var(--grid) 1px,transparent 1px);
  background-size:44px 44px;
  mask-image:radial-gradient(circle at 50% 40%, #000 0%, transparent 75%);
  -webkit-mask-image:radial-gradient(circle at 50% 40%, #000 0%, transparent 75%);
}
.login-card{
  position:relative;z-index:1;width:100%;max-width:400px;
  background:linear-gradient(160deg, rgba(20,30,62,0.92), rgba(12,20,46,0.92));
  border:1px solid rgba(34,211,238,0.35);border-radius:18px;
  box-shadow:var(--glow), var(--shadow);backdrop-filter:blur(8px);
  padding:38px 30px;overflow:hidden;
}
.login-card::after{
  content:"";position:absolute;left:0;top:0;height:3px;width:100%;
  background:linear-gradient(90deg,transparent,var(--primary),var(--primary-2),transparent);
  animation:scan 3s linear infinite;
}
@keyframes scan{0%{transform:translateX(-100%);}100%{transform:translateX(100%);}}
.login-card .logo{font-size:46px;text-align:center;filter:drop-shadow(0 0 12px rgba(34,211,238,.6));}
.login-card h1{
  font-size:23px;text-align:center;margin:10px 0 4px;font-weight:700;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;
  letter-spacing:2px;color:#fff;text-shadow:0 0 16px rgba(34,211,238,.45);
}
.login-card .sub-en{text-align:center;color:var(--primary);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;font-size:11px;letter-spacing:4px;margin-bottom:24px;}
.login-err{color:#ffd0e0;background:var(--wrong-bg);border:1px solid rgba(255,93,143,.4);border-radius:10px;padding:9px 12px;font-size:13px;margin-bottom:12px;display:none;}
.login-err.show{display:block;}
.field{margin-bottom:15px;}
.field label{display:block;font-size:12.5px;font-weight:600;margin-bottom:7px;color:var(--primary);letter-spacing:.5px;text-transform:uppercase;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;}
.field input,.field select,.field textarea{
  width:100%;border:1px solid var(--border);background:rgba(8,14,34,0.7);color:var(--text);
  border-radius:10px;padding:12px 13px;font-size:14px;outline:none;font-family:inherit;
  transition:border-color .15s ease, box-shadow .15s ease;
}
.field input:focus,.field textarea:focus,.field select:focus{border-color:var(--primary);box-shadow:0 0 0 3px rgba(34,211,238,.15);}
.btn-primary{
  width:100%;background:linear-gradient(135deg,var(--primary),var(--primary-2));color:#04121a;border:none;border-radius:10px;
  padding:13px;font-size:15px;font-weight:700;cursor:pointer;letter-spacing:2px;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;
  box-shadow:0 0 18px rgba(34,211,238,.45);transition:transform .12s ease, box-shadow .15s ease;
}
.btn-primary:hover{box-shadow:0 0 26px rgba(34,211,238,.65);}
.btn-primary:active{transform:scale(.98);}
.btn-primary:disabled{opacity:.6;}
.login-tip{text-align:center;color:var(--muted);font-size:12px;margin-top:16px;line-height:1.7;}

/* ================= 顶栏 ================= */
.navbar{
  position:relative;z-index:1;
  background:linear-gradient(90deg, rgba(16,24,51,0.92), rgba(12,20,46,0.92));
  border-bottom:1px solid rgba(34,211,238,0.22);
  display:flex;align-items:center;justify-content:space-between;padding:13px 22px;gap:12px;flex-wrap:wrap;
  backdrop-filter:blur(6px);
}
.navbar .brand{font-size:17px;font-weight:700;display:flex;align-items:center;gap:10px;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;letter-spacing:1px;color:#fff;}
.navbar .brand .dot{width:10px;height:10px;border-radius:50%;background:var(--primary);box-shadow:var(--glow);animation:pulse 2s infinite;}
@keyframes pulse{0%,100%{opacity:1;}50%{opacity:.35;}}
.navbar .nav-actions{display:flex;gap:10px;align-items:center;font-size:13px;color:var(--muted);}
.tabs{position:relative;z-index:1;display:flex;gap:4px;flex-wrap:wrap;background:rgba(12,20,46,0.6);border-bottom:1px solid var(--border);padding:0 20px;}
.tabs button{
  background:none;border:none;padding:13px 16px;font-size:14px;font-weight:600;color:var(--muted);
  cursor:pointer;border-bottom:2px solid transparent;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;letter-spacing:.5px;transition:color .15s ease;
}
.tabs button:hover{color:var(--primary);}
.tabs button.active{color:var(--primary);border-bottom-color:var(--primary);text-shadow:0 0 12px rgba(34,211,238,.5);}

.wrap{position:relative;z-index:1;max-width:1180px;margin:0 auto;padding:22px;}

/* 卡片 / 统计 */
.stat-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:14px;margin-bottom:22px;}
.stat-card{
  background:var(--card);border:1px solid var(--border);border-radius:14px;box-shadow:var(--shadow);
  padding:18px 20px;position:relative;overflow:hidden;backdrop-filter:blur(6px);
}
.stat-card::before{content:"";position:absolute;right:-20px;top:-20px;width:80px;height:80px;border-radius:50%;background:radial-gradient(circle,rgba(34,211,238,.18),transparent 70%);}
.stat-card .num{font-size:28px;font-weight:700;color:var(--primary);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;text-shadow:0 0 14px rgba(34,211,238,.4);}
.stat-card .lbl{font-size:12.5px;color:var(--muted);margin-top:4px;letter-spacing:.5px;}

.panel{background:var(--card);border:1px solid var(--border);border-radius:14px;box-shadow:var(--shadow);padding:18px;margin-bottom:18px;backdrop-filter:blur(6px);}
.panel h3{margin:0 0 14px;font-size:15px;font-weight:700;color:#fff;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;letter-spacing:.5px;}
.panel-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:14px;gap:10px;flex-wrap:wrap;}
.panel-head h3{margin:0;}

.toolbar{display:flex;gap:10px;flex-wrap:wrap;align-items:center;margin-bottom:14px;}
.toolbar input,.toolbar select{
  border:1px solid var(--border);background:rgba(8,14,34,0.7);color:var(--text);
  border-radius:10px;padding:9px 12px;font-size:13px;outline:none;font-family:inherit;
}
.toolbar input:focus,.toolbar select:focus{border-color:var(--primary);}
.btn{
  background:linear-gradient(135deg,var(--primary),var(--primary-2));color:#04121a;border:none;border-radius:10px;padding:9px 15px;
  font-size:13px;font-weight:700;cursor:pointer;letter-spacing:.5px;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;transition:box-shadow .15s ease, transform .12s ease;
}
.btn:hover{box-shadow:0 0 16px rgba(34,211,238,.45);}
.btn:active{transform:scale(.97);}
.btn.ghost{background:transparent;color:var(--text);border:1px solid var(--border);}
.btn.ghost:hover{border-color:var(--primary);color:var(--primary);box-shadow:none;}
.btn.danger{background:linear-gradient(135deg,#ff5d8f,#ff3d6e);color:#fff;}
.btn.small{padding:6px 11px;font-size:12px;}

/* 表格 */
.table-wrap{overflow-x:auto;-webkit-overflow-scrolling:touch;}
table{width:100%;border-collapse:collapse;font-size:13px;min-width:640px;}
th,td{padding:11px 13px;text-align:left;border-bottom:1px solid var(--border);white-space:nowrap;}
th{color:var(--primary);font-size:11.5px;font-weight:700;background:rgba(8,14,34,0.6);letter-spacing:.5px;text-transform:uppercase;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;}
tbody tr:hover{background:rgba(34,211,238,0.06);}
.tag{display:inline-block;font-size:11px;font-weight:700;border-radius:6px;padding:3px 9px;letter-spacing:.5px;}
.tag.mc{background:rgba(106,139,255,0.16);color:#9db4ff;}
.tag.tf{background:rgba(255,184,77,0.16);color:var(--warn);}
.tag.on{background:var(--correct-bg);color:var(--correct);}
.tag.off{background:var(--wrong-bg);color:var(--wrong);}
.cell-actions{display:flex;gap:6px;}

.empty{text-align:center;color:var(--muted);padding:30px 0;font-size:13px;}
.pager{display:flex;gap:8px;align-items:center;justify-content:flex-end;margin-top:14px;font-size:13px;color:var(--muted);}

/* 弹窗 */
.modal-mask{position:fixed;inset:0;background:rgba(4,8,20,0.7);backdrop-filter:blur(3px);display:none;align-items:center;justify-content:center;z-index:60;padding:16px;}
.modal-mask.show{display:flex;}
.modal{background:linear-gradient(160deg, rgba(20,30,62,0.96), rgba(12,20,46,0.96));border:1px solid rgba(34,211,238,0.3);border-radius:16px;width:100%;max-width:520px;max-height:88vh;overflow-y:auto;padding:22px;box-shadow:var(--glow),var(--shadow);}
.modal h3{margin:0 0 16px;font-size:16px;color:#fff;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;letter-spacing:.5px;}
.modal .modal-actions{display:flex;gap:10px;justify-content:flex-end;margin-top:18px;flex-wrap:wrap;}
.opt-row{display:flex;gap:8px;align-items:center;margin-bottom:8px;}
.opt-row .letter{
  flex:0 0 auto;width:30px;height:30px;border-radius:50%;background:rgba(8,14,34,0.7);border:1px solid var(--border);
  display:flex;align-items:center;justify-content:center;font-weight:700;font-size:12px;color:var(--primary);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;
}
.opt-row input{flex:1;}
.hint{font-size:12px;color:var(--muted);margin-top:4px;}

/* 成就小卡 */
.ach-list{display:grid;grid-template-columns:repeat(auto-fill,minmax(140px,1fr));gap:10px;}
.ach-item{border:1px solid var(--border);border-radius:12px;padding:12px;text-align:center;background:rgba(12,20,46,0.6);}
.ach-item.locked{opacity:.45;}
.ach-item .ic{font-size:24px;filter:drop-shadow(0 0 8px rgba(34,211,238,.4));}
.ach-item .nm{font-size:12.5px;font-weight:700;margin-top:5px;color:#fff;}
.ach-item .ds{font-size:11px;color:var(--muted);}

.toast{
  position:fixed;top:18px;left:50%;transform:translateX(-50%) translateY(-20px);
  background:linear-gradient(135deg,var(--primary),var(--primary-2));color:#04121a;padding:12px 18px;border-radius:12px;font-size:13.5px;font-weight:700;
  box-shadow:var(--glow);z-index:90;opacity:0;transition:all .3s ease;max-width:90vw;text-align:center;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;letter-spacing:.5px;
}
.toast.show{opacity:1;transform:translateX(-50%) translateY(0);}

@media (max-width:640px){
  .wrap{padding:14px;}
  .navbar{padding:10px 14px;}
  .tabs{padding:0 14px;overflow-x:auto;}
  .stat-grid{grid-template-columns:repeat(2,1fr);}
  .modal{max-height:92vh;}
}