/* ============================================================
   课堂考勤系统 · 管理后台 深色科技风样式
   基底 #05070D · 主色 青→靛渐变 · 状态四色语义
   ============================================================ */
:root{
  --bg:#05070d; --bg2:#080d18; --panel:rgba(255,255,255,.028); --panel2:rgba(255,255,255,.05);
  --line:rgba(255,255,255,.075); --line2:rgba(255,255,255,.14);
  --txt:#e6edf7; --txt2:#9aa7bd; --txt3:#5f6b80;
  --cyan:#22d3ee; --indigo:#818cf8; --emerald:#34d399; --amber:#fbbf24; --red:#f87171; --purple:#a78bfa;
  --grad:linear-gradient(135deg,#22d3ee,#818cf8);
  --side-w:228px; --top-h:58px; --radius:14px;
}
*{margin:0;padding:0;box-sizing:border-box}
body{
  background:var(--bg); color:var(--txt); font-size:14px; line-height:1.6;
  font-family:-apple-system,BlinkMacSystemFont,"SF Pro Display","PingFang SC","Microsoft YaHei",sans-serif;
  background-image:
    radial-gradient(ellipse 800px 420px at 12% -8%, rgba(34,211,238,.07), transparent 60%),
    radial-gradient(ellipse 700px 420px at 95% 0%, rgba(129,140,248,.08), transparent 60%);
  background-attachment:fixed;
}
a{color:inherit;text-decoration:none}
::selection{background:rgba(34,211,238,.3)}

/* ---------- 布局 ---------- */
.layout{display:flex;min-height:100vh}
.main{flex:1;margin-left:var(--side-w);display:flex;flex-direction:column;min-width:0}

/* ---------- 侧边栏 ---------- */
.side{
  position:fixed;left:0;top:0;bottom:0;width:var(--side-w);z-index:50;
  background:linear-gradient(180deg,rgba(10,15,28,.92),rgba(5,7,13,.96));
  border-right:1px solid var(--line);display:flex;flex-direction:column;
}
.logo{height:var(--top-h);display:flex;align-items:center;gap:10px;padding:0 18px;border-bottom:1px solid var(--line)}
.logo .mark{width:26px;height:26px;border-radius:8px;background:var(--grad);position:relative;flex-shrink:0}
.logo .mark::after{content:"";position:absolute;inset:6px;border-radius:3px;border:2px solid rgba(5,7,13,.75)}
.logo b{font-size:14.5px;letter-spacing:.5px;background:var(--grad);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
.logo small{display:block;font-size:9.5px;color:var(--txt3);letter-spacing:2.5px}
nav{flex:1;padding:14px 10px;overflow-y:auto}
.nav-item{
  display:flex;align-items:center;gap:11px;padding:10px 14px;margin-bottom:3px;
  border-radius:10px;color:var(--txt2);font-size:13.5px;position:relative;transition:.18s;
}
.nav-item .ic{width:20px;text-align:center;font-size:15px;opacity:.85}
.nav-item:hover{color:var(--txt);background:var(--panel2)}
.nav-item.on{color:var(--txt);background:linear-gradient(90deg,rgba(34,211,238,.13),rgba(129,140,248,.08))}
.nav-item.on::before{content:"";position:absolute;left:0;top:20%;bottom:20%;width:3px;border-radius:3px;background:var(--grad);box-shadow:0 0 10px rgba(34,211,238,.7)}
.nav-group{padding:12px 14px 4px;font-size:10.5px;letter-spacing:2px;color:var(--txt3);border-top:1px solid var(--line);margin-top:8px}
.nav-item.sub{padding-left:26px;font-size:13px}
.side-foot{padding:14px 16px;border-top:1px solid var(--line);font-size:11px;color:var(--txt3)}
.side-foot .env{display:inline-flex;align-items:center;gap:6px;padding:3px 10px;border:1px solid rgba(52,211,153,.35);border-radius:99px;color:var(--emerald);font-size:10.5px;letter-spacing:1px}
.side-foot .env i{width:6px;height:6px;border-radius:50%;background:var(--emerald);box-shadow:0 0 7px var(--emerald)}

/* ---------- 顶栏 ---------- */
.top{
  position:sticky;top:0;z-index:40;height:var(--top-h);
  display:flex;align-items:center;justify-content:space-between;padding:0 26px;
  background:rgba(5,7,13,.78);backdrop-filter:blur(14px);border-bottom:1px solid var(--line);
}
.crumb{font-size:13px;color:var(--txt3)}
.crumb b{color:var(--txt);font-weight:600;font-size:14.5px;margin-left:8px}
.top-right{display:flex;align-items:center;gap:14px;font-size:12.5px;color:var(--txt2)}
.avatar{width:30px;height:30px;border-radius:50%;background:var(--grad);display:flex;align-items:center;justify-content:center;font-size:12px;font-weight:700;color:#04121a}

/* ---------- 内容 ---------- */
.content{padding:26px;max-width:1280px;width:100%;margin:0 auto}
.page-title{font-size:21px;font-weight:700;letter-spacing:-.2px;margin-bottom:4px}
.page-sub{font-size:12.5px;color:var(--txt3);margin-bottom:22px}

/* ---------- 统计卡 ---------- */
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;margin-bottom:20px}
.stat{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:16px 18px;position:relative;overflow:hidden}
.stat::after{content:"";position:absolute;right:-28px;top:-28px;width:80px;height:80px;border-radius:50%;background:radial-gradient(circle,rgba(34,211,238,.12),transparent 70%)}
.stat .k{font-size:26px;font-weight:700;font-variant-numeric:tabular-nums}
.stat .k span{font-size:13px;color:var(--txt3);font-weight:400;margin-left:3px}
.stat .l{font-size:12px;color:var(--txt2);margin-top:2px}
.stat .k.g-cyan{background:var(--grad);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
.stat .k.g-green{color:var(--emerald)} .stat .k.g-red{color:var(--red)}
.stat .k.g-purple{color:var(--purple)} .stat .k.g-amber{color:var(--amber)}

/* ---------- 卡片 / 面板 ---------- */
.panel{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);margin-bottom:18px;overflow:hidden}
.panel-h{display:flex;align-items:center;justify-content:space-between;padding:14px 18px;border-bottom:1px solid var(--line)}
.panel-h h3{font-size:14.5px;font-weight:600}
.panel-h .hint{font-size:11.5px;color:var(--txt3)}
.panel-b{padding:16px 18px}
.grid2{display:grid;grid-template-columns:1.2fr 1fr;gap:18px}
.grid2e{display:grid;grid-template-columns:1fr 1fr;gap:18px}

/* ---------- 表格 ---------- */
table{width:100%;border-collapse:collapse;font-size:13px}
th{text-align:left;padding:9px 14px;font-size:11px;letter-spacing:1.2px;color:var(--txt3);font-weight:600;border-bottom:1px solid var(--line2);white-space:nowrap}
td{padding:10px 14px;border-bottom:1px solid var(--line);vertical-align:middle;color:var(--txt)}
tr:last-child td{border-bottom:none}
tbody tr{transition:.15s}
tbody tr:hover{background:rgba(255,255,255,.025)}
.mono{font-family:ui-monospace,Menlo,Consolas,monospace;font-size:12px;color:var(--cyan)}
.dim{color:var(--txt3);font-size:12px}

/* ---------- 徽章 / 状态 ---------- */
.badge{display:inline-flex;align-items:center;gap:6px;padding:3px 10px;border-radius:99px;font-size:11.5px;font-weight:600;border:1px solid;white-space:nowrap}
.badge i{width:6px;height:6px;border-radius:50%}
.b-green{color:var(--emerald);border-color:rgba(52,211,153,.4);background:rgba(52,211,153,.07)} .b-green i{background:var(--emerald)}
.b-red{color:var(--red);border-color:rgba(248,113,113,.4);background:rgba(248,113,113,.07)} .b-red i{background:var(--red)}
.b-amber{color:var(--amber);border-color:rgba(251,191,36,.4);background:rgba(251,191,36,.07)} .b-amber i{background:var(--amber)}
.b-purple{color:var(--purple);border-color:rgba(167,139,250,.4);background:rgba(167,139,250,.07)} .b-purple i{background:var(--purple)}
.b-cyan{color:var(--cyan);border-color:rgba(34,211,238,.4);background:rgba(34,211,238,.07)} .b-cyan i{background:var(--cyan)}
.b-gray{color:var(--txt2);border-color:var(--line2);background:var(--panel2)} .b-gray i{background:var(--txt3)}

/* ---------- 进度条 ---------- */
.bar{height:8px;border-radius:5px;background:var(--panel2);overflow:hidden;border:1px solid var(--line)}
.bar i{display:block;height:100%;border-radius:5px;background:var(--grad)}
.bar i.g-green{background:var(--emerald)} .bar i.g-red{background:var(--red)}
.bar i.g-amber{background:var(--amber)} .bar i.g-purple{background:var(--purple)}
.dist{display:grid;gap:10px}
.dist .row{display:grid;grid-template-columns:64px 1fr 70px;align-items:center;gap:12px;font-size:12.5px}
.dist .row .n{font-variant-numeric:tabular-nums;text-align:right;color:var(--txt2)}

/* ---------- 按钮 / 表单 ---------- */
.btn{display:inline-flex;align-items:center;gap:7px;padding:8px 16px;border-radius:9px;border:1px solid var(--line2);
  background:var(--panel2);color:var(--txt);font-size:12.5px;cursor:pointer;transition:.18s}
.btn:hover{border-color:rgba(34,211,238,.5);color:var(--cyan)}
.btn.primary{background:var(--grad);border:none;color:#04121a;font-weight:700}
.btn.primary:hover{opacity:.88}
.btn.sm{padding:5px 11px;font-size:11.5px;border-radius:7px}
input[type=text],input[type=password],select{
  background:var(--bg2);border:1px solid var(--line2);border-radius:9px;padding:9px 13px;
  color:var(--txt);font-size:13px;outline:none;transition:.18s;min-width:190px}
input:focus,select:focus{border-color:rgba(34,211,238,.55);box-shadow:0 0 0 3px rgba(34,211,238,.1)}
.setting-row{display:grid;grid-template-columns:220px 1fr;gap:14px;align-items:center;padding:12px 0;border-bottom:1px solid var(--line)}
.setting-row:last-child{border-bottom:none}
.setting-row .sk{font-size:13px;font-weight:600}
.setting-row .sd{font-size:11.5px;color:var(--txt3)}
.setting-row input{width:100%;max-width:460px}

/* ---------- 课程时间轴卡 ---------- */
.course-cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:14px}
.ccard{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:16px;position:relative;overflow:hidden}
.ccard::before{content:"";position:absolute;left:0;top:0;bottom:0;width:3px;background:var(--grad)}
.ccard .t{font-size:15px;font-weight:700}
.ccard .cls{font-size:11.5px;color:var(--cyan);border:1px solid rgba(34,211,238,.35);padding:1px 8px;border-radius:99px;margin-left:8px}
.ccard .meta{margin-top:9px;font-size:12px;color:var(--txt2);display:grid;gap:4px}
.ccard .meta b{color:var(--txt3);font-weight:400;margin-right:6px}

/* ---------- 登录页 ---------- */
.login-wrap{min-height:100vh;display:flex;align-items:center;justify-content:center;
  background:var(--bg);
  background-image:
    radial-gradient(ellipse 900px 500px at 20% 0%, rgba(34,211,238,.10), transparent 60%),
    radial-gradient(ellipse 800px 500px at 85% 100%, rgba(129,140,248,.10), transparent 60%);}
.login-card{width:380px;background:rgba(10,15,28,.8);border:1px solid var(--line2);border-radius:20px;padding:38px 34px;backdrop-filter:blur(10px)}
.login-card .mark{width:44px;height:44px;border-radius:13px;background:var(--grad);margin:0 auto 16px;position:relative}
.login-card .mark::after{content:"";position:absolute;inset:11px;border-radius:4px;border:3px solid rgba(5,7,13,.75)}
.login-card h1{text-align:center;font-size:19px;letter-spacing:.5px}
.login-card h1 span{background:var(--grad);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
.login-card .sub{text-align:center;font-size:11px;color:var(--txt3);letter-spacing:3px;margin:4px 0 26px}
.login-card input{width:100%;margin-bottom:12px;min-width:0}
.login-card .btn{width:100%;justify-content:center;padding:11px;font-size:13.5px}
.login-foot{margin-top:18px;text-align:center;font-size:11px;color:var(--txt3)}

@media (max-width:960px){
  :root{--side-w:0px}
  .side{display:none}
  .main{margin-left:0}
  .stats{grid-template-columns:repeat(2,1fr)}
  .grid2,.grid2e{grid-template-columns:1fr}
}

/* 基础参数：版块分组折叠卡 */
.settings-save-bar{display:flex;justify-content:flex-end;align-items:center;gap:14px;margin:14px 0 6px}
.settings-group{background:rgba(255,255,255,.03);border:1rpx solid rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.08);border-radius:14px;margin:10px 0;overflow:hidden}
.settings-group summary{cursor:pointer;list-style:none;padding:14px 18px;user-select:none}
.settings-group summary::-webkit-details-marker{display:none}
.settings-group[open] summary{border-bottom:1px solid var(--line)}
.sg-head{display:flex;align-items:center;gap:14px}
.sg-title{font-weight:600;font-size:14.5px;color:var(--txt)}
.sg-desc{font-size:12px;color:var(--dim);margin-top:2px}
.sg-summary{margin-left:auto;font-size:12.5px;color:var(--cyan);background:rgba(34,211,238,.07);border:1px solid rgba(34,211,238,.25);border-radius:999px;padding:3px 14px;max-width:46%;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.sg-arrow{color:var(--dim);transition:transform .18s;font-size:12px}
.settings-group[open] .sg-arrow{transform:rotate(180deg)}
.sg-body{padding:4px 18px 12px}
.settings-group.deprecated{opacity:.62}
.settings-group.deprecated .sg-summary{display:none}
.deprecated-input{opacity:.7}

/* ---- 全站 toast（成功/警示）与按钮 loading ---- */
#flash-data{display:none}
.toast{position:fixed;top:18px;right:18px;z-index:9999;max-width:420px;
  padding:13px 20px;border-radius:12px;font-size:13.5px;line-height:1.55;
  color:#04121a;font-weight:600;box-shadow:0 10px 34px rgba(0,0,0,.42);
  opacity:0;transform:translateY(-8px);transition:opacity .28s,transform .28s;cursor:pointer}
.toast.show{opacity:1;transform:translateY(0)}
.toast-ok{background:linear-gradient(135deg,#22d3ee,#5eead4);border:1px solid rgba(255,255,255,.28)}
.toast-warn{background:linear-gradient(135deg,#fbbf24,#f59e0b);color:#241a04;border:1px solid rgba(255,255,255,.3)}
.btn-loading{opacity:.72;letter-spacing:.5px;cursor:progress}

/* 点击大图 lightbox */
.lightbox{position:fixed;inset:0;z-index:9998;background:rgba(2,6,14,.86);
  display:flex;align-items:center;justify-content:center;cursor:zoom-out;padding:40px}
.lightbox img{max-width:88vw;max-height:86vh;border-radius:14px;
  box-shadow:0 22px 70px rgba(0,0,0,.6);border:1px solid rgba(255,255,255,.14)}
img.zoomable{cursor:zoom-in}
/* 底库照片网格 */
.photo-grid{display:flex;flex-wrap:wrap;gap:12px;margin:6px 0 12px}
.photo-cell{position:relative;width:96px;height:96px}
.face-grid-img{width:96px;height:96px;border-radius:12px;object-fit:cover;border:1px solid var(--line)}
.face-empty-miss{background:rgba(255,255,255,.04)}
.photo-del{position:absolute;top:-8px;right:-8px;padding:2px 9px;font-size:11px;border-radius:999px}
.pager{display:flex;gap:14px;align-items:center;padding:12px 16px;border-top:1px solid var(--line)}

/* 学生底库照片缩略图与预览 */
.face-thumb{width:42px;height:42px;border-radius:10px;object-fit:cover;border:1px solid var(--line);vertical-align:middle}
.face-preview{width:84px;height:84px;border-radius:14px;object-fit:cover;border:1px solid var(--line)}
.face-empty{display:flex;align-items:center;justify-content:center;font-size:11px;color:var(--dim);background:rgba(255,255,255,.03)}