/* ===== 基础 ===== */
:root{
  --bg:#f2f5fb;
  --surface:#ffffff;
  --ink:#141c2e;
  --ink-2:#54607a;
  --ink-3:#8892a8;
  --line:#e0e6f1;
  --brand:#112a76;         /* 墨蓝 · 取自 Logo 最深处 #071b69 */
  --brand-dark:#0a1b55;
  --brand-soft:#e9eefb;
  --brand-2:#0254bb;       /* 中蓝 · 取自 Logo 主体 */
  --amber:#c98a17;
  --ok:#2a7a4b;
  --warn:#b9761c;
  --radius:14px;
  --shadow:0 1px 2px rgba(18,30,66,.06), 0 6px 20px rgba(18,30,66,.07);
  --font:"Noto Sans", "Segoe UI", system-ui, -apple-system, "Helvetica Neue", Arial,
         "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{
  font-family:var(--font);
  background:var(--bg);
  color:var(--ink);
  -webkit-font-smoothing:antialiased;
  line-height:1.55;
}
a{color:inherit;text-decoration:none}
button{font-family:inherit}
.hidden{display:none !important}

/* ===== 顶栏 ===== */
.topbar{
  position:sticky;top:0;z-index:50;
  background:rgba(255,255,255,.92);
  backdrop-filter:saturate(180%) blur(8px);
  border-bottom:1px solid var(--line);
}
.topbar-in{
  max-width:1080px;margin:0 auto;padding:10px 16px;
  display:flex;align-items:center;gap:12px;
}
.logo{
  width:40px;height:40px;flex:none;position:relative;
  display:grid;place-items:center;
}
.logo span{width:100%;height:100%;border-radius:11px;background:var(--brand);color:#fff;
  display:grid;place-items:center;font-size:19px;font-weight:700;letter-spacing:-1px}
.logo img{position:absolute;inset:0;width:100%;height:100%;object-fit:contain}
.logo img + span{display:none}
.brand-txt{min-width:0;flex:1}
.brand-txt b{display:block;font-size:15px;line-height:1.25;
  overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.brand-txt span{display:block;font-size:11.5px;color:var(--ink-3);
  overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.top-actions{display:flex;align-items:center;gap:8px;flex:none}
.avatar{width:32px;height:32px;border-radius:50%;object-fit:cover;
  border:1px solid var(--line);background:#ddd}

.btn{
  border:1px solid var(--line);background:var(--surface);color:var(--ink);
  padding:7px 13px;border-radius:9px;font-size:13.5px;cursor:pointer;
  transition:.15s;white-space:nowrap;
}
.btn:hover{border-color:var(--ink-3)}
.btn-primary{background:var(--brand);color:#fff;border-color:var(--brand)}
.btn-primary:hover{background:var(--brand-dark);border-color:var(--brand-dark)}
.btn-ghost{background:transparent;border-color:transparent;color:var(--ink-2)}
.btn-ghost:hover{background:#0000000a}
.btn-sm{padding:4px 9px;font-size:12.5px;border-radius:7px}
.btn-danger{color:#a32718;border-color:#f0d3cd}
.btn-danger:hover{background:#fdf0ec}

/* ===== 登录屏 ===== */
.gate{
  min-height:100dvh;display:grid;place-items:center;padding:24px 18px;
  background:
    radial-gradient(900px 500px at 12% -8%, #dfe8fb 0%, transparent 60%),
    radial-gradient(800px 500px at 100% 0%, #e6f0fd 0%, transparent 55%),
    var(--bg);
}
.gate-card{
  width:100%;max-width:420px;background:var(--surface);
  border:1px solid var(--line);border-radius:20px;
  box-shadow:var(--shadow);padding:34px 28px;text-align:center;
}
.gate-logo{
  width:136px;min-height:104px;margin:0 auto 14px;position:relative;
  display:grid;place-items:center;
}
.gate-logo span{
  width:76px;height:76px;border-radius:20px;background:var(--brand);color:#fff;
  display:grid;place-items:center;font-size:38px;font-weight:700;
}
.gate-logo img{width:100%;height:auto;max-height:172px;object-fit:contain;display:block}
.gate-logo img + span{display:none}
.gate-card h1{font-size:21px;margin:0 0 6px;letter-spacing:-.2px}
.gate-card .sub{color:var(--ink-2);font-size:14px;margin:0 0 26px}
.gate-note{font-size:12.5px;color:var(--ink-3);margin-top:20px;line-height:1.6}
.gsi{
  width:100%;display:flex;align-items:center;justify-content:center;gap:10px;
  padding:12px;border-radius:11px;border:1px solid var(--line);
  background:#fff;font-size:15px;font-weight:600;cursor:pointer;transition:.15s;
}
.gsi:hover{box-shadow:0 2px 10px rgba(16,32,80,.12);border-color:#c2cde3}
.gsi svg{width:19px;height:19px;flex:none}
.status-box{
  margin-top:18px;padding:14px;border-radius:11px;font-size:13.5px;line-height:1.6;
}
.status-wait{background:#fff8e9;border:1px solid #f0e0bd;color:#7a5a12}
.status-err {background:#fdf0ec;border:1px solid #f0d3cb;color:#8f2b1a}

/* ===== 主体 ===== */
.wrap{max-width:1080px;margin:0 auto;padding:0 16px 80px}

/* 篇章标签 */
.sections{
  display:flex;gap:8px;overflow-x:auto;padding:14px 0 4px;
  scrollbar-width:none;-ms-overflow-style:none;
}
.sections::-webkit-scrollbar{display:none}
.sec-tab{
  flex:none;padding:9px 16px;border-radius:999px;cursor:pointer;
  border:1px solid var(--line);background:var(--surface);
  font-size:14px;color:var(--ink-2);transition:.15s;
}
.sec-tab small{display:block;font-size:11px;color:var(--ink-3);margin-top:-1px}
.sec-tab:hover{border-color:var(--ink-3)}
.sec-tab.on{background:var(--ink);border-color:var(--ink);color:#fff}
.sec-tab.on small{color:#ffffff9c}

/* 子页标签 */
.subs{display:flex;flex-wrap:wrap;gap:7px;padding:14px 0 6px;border-bottom:1px solid var(--line)}
.sub-tab{
  padding:6px 13px;border-radius:8px;cursor:pointer;font-size:13.5px;
  border:1px solid transparent;background:transparent;color:var(--ink-2);transition:.15s;
}
.sub-tab:hover{background:#00000008}
.sub-tab.on{background:var(--brand-soft);color:var(--brand);border-color:#d3dcf6;font-weight:600}
.sub-tab .cnt{font-size:11px;color:var(--ink-3);margin-left:4px}

/* 链接卡片 */
.cards{
  display:grid;gap:12px;padding:20px 0;
  grid-template-columns:repeat(auto-fill,minmax(268px,1fr));
}
.card{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:16px 16px 14px;box-shadow:var(--shadow);
  display:flex;flex-direction:column;gap:8px;
  transition:.16s;cursor:pointer;position:relative;
}
.card:hover{transform:translateY(-2px);border-color:#c8d2e6;
  box-shadow:0 2px 4px rgba(18,30,66,.08),0 12px 28px rgba(18,30,66,.12)}
.card h3{margin:0;font-size:16px;font-weight:650;letter-spacing:-.1px}
.card .vi{font-size:13px;color:var(--brand-2);margin:0}
.card .note{font-size:12.5px;color:var(--ink-3);margin:0}
.card .go{
  margin-top:auto;padding-top:8px;font-size:12.5px;color:var(--ink-3);
  display:flex;align-items:center;gap:5px;
}
.card .badge{
  position:absolute;top:12px;right:12px;font-size:10.5px;
  background:var(--brand-soft);color:var(--brand);
  padding:2px 7px;border-radius:5px;font-weight:600;
}
.card .adm{display:flex;gap:6px;margin-top:8px}

/* 空状态 */
.empty{
  padding:56px 20px;text-align:center;color:var(--ink-3);font-size:14px;
}
.empty .ico{font-size:34px;display:block;margin-bottom:10px;opacity:.55}

/* ===== 管理后台 ===== */
.admin-head{
  display:flex;align-items:center;gap:10px;flex-wrap:wrap;
  padding:18px 0 10px;border-bottom:1px solid var(--line);
}
.admin-head h2{margin:0;font-size:19px;flex:1}
.admin-tabs{display:flex;gap:6px;padding:14px 0}
.atab{
  padding:6px 13px;border-radius:8px;cursor:pointer;font-size:13.5px;
  border:1px solid var(--line);background:var(--surface);color:var(--ink-2);
}
.atab.on{background:var(--ink);color:#fff;border-color:var(--ink)}

table{width:100%;border-collapse:collapse;font-size:13.5px;background:var(--surface);
  border:1px solid var(--line);border-radius:var(--radius);overflow:hidden}
th{text-align:left;font-size:12px;text-transform:uppercase;letter-spacing:.4px;
  color:var(--ink-3);font-weight:600;padding:10px 12px;background:#f7f9fd;
  border-bottom:1px solid var(--line);white-space:nowrap}
td{padding:10px 12px;border-bottom:1px solid #eef1f7;vertical-align:middle}
tr:last-child td{border-bottom:none}
.table-scroll{overflow-x:auto;-webkit-overflow-scrolling:touch}
.pill{font-size:11.5px;padding:2px 8px;border-radius:999px;white-space:nowrap}
.pill-ok{background:#e8f4ec;color:var(--ok)}
.pill-wait{background:#fff5e0;color:var(--warn)}
.pill-no{background:#fbeae7;color:#a32718}

.form-row{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:10px}
.field{flex:1;min-width:180px;display:flex;flex-direction:column;gap:4px}
.field label{font-size:12px;color:var(--ink-2);font-weight:600}
input[type=text],input[type=url],select,textarea{
  padding:9px 11px;border:1px solid var(--line);border-radius:9px;
  font-family:inherit;font-size:14px;background:#fff;color:var(--ink);width:100%;
}
input:focus,select:focus,textarea:focus{outline:2px solid #112a7633;border-color:var(--brand)}
.panel{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:16px;margin:14px 0;box-shadow:var(--shadow);
}
.panel h3{margin:0 0 12px;font-size:15px}

.stat-row{display:grid;gap:12px;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));margin:14px 0}
.stat{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:14px 16px;box-shadow:var(--shadow)}
.stat b{display:block;font-size:26px;letter-spacing:-.8px;line-height:1.2}
.stat span{font-size:12px;color:var(--ink-3)}

/* ===== 提示条 ===== */
.toast{
  position:fixed;left:50%;bottom:26px;transform:translateX(-50%) translateY(12px);
  background:var(--ink);color:#fff;padding:11px 18px;border-radius:11px;
  font-size:13.5px;box-shadow:0 8px 30px rgba(0,0,0,.25);
  opacity:0;pointer-events:none;transition:.22s;z-index:200;max-width:88vw;text-align:center;
}
.toast.on{opacity:1;transform:translateX(-50%) translateY(0)}

.demo-bar{
  background:#fff5e0;border-bottom:1px solid #f0e0bd;color:#7a5a12;
  font-size:12.5px;padding:7px 16px;text-align:center;
}

@media (max-width:560px){
  .cards{grid-template-columns:1fr}
  .gate-card{padding:28px 20px}
  .brand-txt span{display:none}
}

/* ===== 班级选择 / 复选框 ===== */
#classPick{margin-top:20px;text-align:left}
#classPick label[for=selClass]{display:block;font-size:14px;font-weight:600;margin-bottom:8px}
#classPick label[for=selClass] span{font-weight:400;color:var(--ink-3);font-size:12.5px}
#classPick select{margin-bottom:10px}
#classPick .btn-primary{width:100%;padding:11px}

.my-class{
  font-size:12px;padding:3px 9px;border-radius:999px;
  background:var(--brand-soft);color:var(--brand);font-weight:600;white-space:nowrap;
}
.chk-row{display:flex;flex-wrap:wrap;gap:6px;padding:7px 0}
.chk{
  display:inline-flex;align-items:center;gap:6px;font-size:13.5px;color:var(--ink-2);
  border:1px solid var(--line);background:#fff;border-radius:8px;padding:6px 11px;cursor:pointer;
}
.chk:hover{border-color:var(--ink-3)}
.chk input{accent-color:var(--brand);margin:0}
input[type=datetime-local]{
  padding:9px 11px;border:1px solid var(--line);border-radius:9px;
  font-family:inherit;font-size:14px;background:#fff;color:var(--ink);width:100%;
}
@media (max-width:560px){ .my-class{display:none} }