:root{
  --bg:#f7f8fa; --card:#fff; --ink:#1f2933; --sub:#5b6b7b;
  --brand:#1f6feb; --brand2:#0b3d91; --line:#e4e8ee; --soft:#eef3fb;
  --ok:#2e7d32; --warn:#b4690e;
}
*{box-sizing:border-box;margin:0;padding:0}
body{font-family:-apple-system,"PingFang SC","Microsoft YaHei",sans-serif;
  background:var(--bg);color:var(--ink);line-height:1.7;-webkit-font-smoothing:antialiased;overflow-y:scroll}
.wrap{max-width:1000px;margin:0 auto;padding:0 20px}
header{background:var(--brand2);color:#fff}
header .wrap{display:flex;align-items:center;justify-content:space-between;height:58px}
.logo{font-weight:800;letter-spacing:.5px;font-size:18px}
nav a{color:rgba(255,255,255,.8);text-decoration:none;margin-left:22px;font-size:15px;
  padding:4px 0;border-bottom:2px solid transparent}
nav a.on{color:#fff;border-bottom-color:#fff}
nav a:hover{color:#fff}
main{padding:30px 0 60px;min-height:60vh}
.sec-title{font-size:22px;font-weight:800;color:var(--brand2);margin-bottom:4px}
.mini{background:#fff;border:1px solid var(--line);color:var(--sub);border-radius:6px;
  padding:3px 10px;font-size:12px;cursor:pointer;font-family:inherit}
.mini:hover{border-color:var(--brand);color:var(--brand)}
.mini.danger{color:#c0392b;border-color:#eccfca}
.mini.danger:hover{border-color:#c0392b;color:#c0392b}
.foot-row{display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap}
.foot-edit{font-size:13px;color:var(--sub)}
.foot-edit .mini{margin:0 3px}
.foot-note{font-size:13px;color:var(--sub)}
.sec-sub{color:var(--sub);margin-bottom:18px;font-size:14px}
.empty{color:var(--sub);padding:30px;text-align:center}
footer{border-top:1px solid var(--line);padding:22px 0;color:var(--sub);font-size:13px;text-align:center}
@media(max-width:720px){header .wrap{height:auto;flex-direction:column;gap:8px;padding:12px 0}nav a{margin:0 12px 0 0}}

/* ---------- 课程：一屏关键词 ---------- */
.course-view{min-height:calc(100vh - 220px);display:flex;flex-direction:column;
  justify-content:center;align-items:center;text-align:center;padding:10px 0}
.course-tag{font-size:26px;font-weight:800;color:var(--brand2);margin-bottom:26px}
.course-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:16px;width:100%}
.fact{background:var(--card);border:1px solid var(--line);border-radius:14px;
  padding:20px 18px;box-shadow:0 1px 3px rgba(16,24,40,.05)}
.fact .k{font-size:20px;font-weight:800;color:var(--brand);margin-bottom:6px}
.fact .v{font-size:14px;color:var(--sub)}
@media(max-width:720px){.course-grid{grid-template-columns:repeat(2,1fr)}}

/* ---------- 知识子菜单（Tab 样式） ---------- */
.subnav{display:flex;gap:0;border-bottom:1px solid var(--line);margin-bottom:4px}
.subnav button{background:none;border:none;border-bottom:2px solid transparent;
  padding:8px 18px;font-size:14px;color:var(--sub);cursor:pointer;
  margin-bottom:-1px;font-family:inherit}
.subnav button.on{color:var(--brand);border-bottom-color:var(--brand);font-weight:700}
.subnav button:hover{color:var(--ink)}
.know-sub{font-size:13px;color:var(--sub);margin-bottom:14px}

/* ---------- 表格 ---------- */
.kv h3{font-size:19px;color:var(--brand2);margin-bottom:4px}
.kv .kdesc{color:var(--sub);font-size:14px;margin-bottom:16px}
table.grid{width:100%;border-collapse:collapse;background:var(--card);
  border:1px solid var(--line);border-radius:12px;overflow:hidden;font-size:14px}
table.grid th,table.grid td{border:1px solid var(--line);padding:11px 13px;text-align:left;vertical-align:top}
table.grid th{padding:6px 10px;background:var(--soft);color:var(--brand2);font-weight:700}
table.grid tr:nth-child(even) td{background:#fafcff}
table.grid td small{color:var(--sub)}

/* ---------- 三板斧三角形 ---------- */
.tri-wrap{display:flex;justify-content:center;padding:10px 0}
.tri-wrap svg{width:min(560px,100%);height:auto}
.tri-node{fill:#fff;stroke:var(--brand);stroke-width:2}
.tri-label{font-size:16px;font-weight:800;fill:var(--brand2)}
.tri-line{stroke:var(--brand);stroke-width:1.6;stroke-dasharray:5 4}
.tri-desc{margin-top:18px;display:grid;grid-template-columns:repeat(3,1fr);gap:14px}
.tri-desc .d{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:14px}
.tri-desc .d b{color:var(--brand);display:block;margin-bottom:4px}
.tri-desc .d.idea b{color:var(--warn)}
@media(max-width:720px){.tri-desc{grid-template-columns:1fr}}

/* ---------- 班级目录 ---------- */
.cls-dir{display:flex;flex-direction:column;gap:8px}
.cls-item{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:10px 16px;
  cursor:pointer;transition:.12s}
.cls-item:hover{border-color:var(--brand)}
.cnm-row{display:flex;align-items:center;gap:10px;line-height:1.5}
.cnum,.cdt,.ctr,.cln,.cls-item .cnm{font-size:13px;font-weight:700;color:var(--brand2)}
.cnum{background:#c0392b;color:#fff;padding:0 5px;border-radius:3px;min-width:1.5em;text-align:center;display:inline-block;font-size:11px;font-weight:500}
.ctr{display:inline-block;width:3em;text-align:center}
.ctr.empty{color:var(--brand2)}
.cls-item .cnote{font-size:13px;color:var(--sub);line-height:1.5;margin-top:2px;min-height:20px}
.cls-bar{display:flex;justify-content:flex-end;margin-bottom:12px}

/* ---------- 班级日历 ---------- */
.cal-nav-right{margin-left:auto;display:flex;align-items:center;gap:8px}
.cal-nav-title{font-size:15px;font-weight:700;color:var(--brand2);margin:0 4px}
.cal-weekdays{display:grid;grid-template-columns:repeat(7,1fr);gap:3px;margin-bottom:3px}
.cal-weekdays div{text-align:center;color:var(--sub);font-size:12px;padding:2px 0}
.cal-grid{display:grid;grid-template-columns:repeat(7,1fr);gap:3px}
.cal-cell{min-height:60px;background:var(--card);border:1px solid var(--line);border-radius:5px;padding:4px;font-size:11px;overflow:hidden;cursor:pointer}
.cal-cell.empty{background:transparent;border:none}
.cal-cell.today{background:#eef3fb;border-color:var(--brand)}
.cal-day{font-weight:700;color:var(--brand2);margin-bottom:2px;font-size:12px}
.cal-cell.today .cal-day{color:var(--brand)}
.cal-sync{display:flex;align-items:flex-start;margin-bottom:2px;font-size:11px;gap:2px}
.flp{width:2px;min-height:29px;background:#c0392b;flex-shrink:0;border-radius:1px}
.flb{background:#c0392b;color:#fff;padding:0 6px;border-radius:3px;white-space:nowrap;line-height:1.4}
.cal-name{color:var(--brand);padding:0 0}
.cal-note{margin-top:2px;cursor:pointer;color:var(--ink);font-size:11px;line-height:1.3;border-top:1px dashed var(--line);padding:2px 0 0;white-space:pre-wrap}
.btn{border:1px solid var(--brand);background:var(--brand);color:#fff;border-radius:8px;
  padding:7px 14px;font-size:14px;cursor:pointer}
.btn.ghost{background:#fff;color:var(--brand)}
.btn.sm{padding:4px 10px;font-size:13px}
.btn.danger{background:#fff;color:#c0392b;border-color:#c0392b}
.btn:hover{opacity:.9}

/* ---------- 班级详情 ---------- */
.back{color:var(--brand);font-size:14px;cursor:pointer;margin-bottom:14px;display:inline-block}
.detail-head{display:flex;align-items:center;gap:14px;flex-wrap:wrap;margin-bottom:16px}
.detail-name{font-size:22px;font-weight:800;color:var(--brand2)}
.detail-date{font-size:13px;color:#fff;background:var(--brand);border-radius:6px;padding:2px 10px;display:inline-block}
.detail-head .mini{margin-left:auto}
.detail-date.empty{background:#9aa7b5}
.block{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:18px 20px;margin-bottom:18px}
.block .bh{font-size:16px;font-weight:800;color:var(--warn);margin-bottom:10px;display:flex;justify-content:space-between;align-items:center}
.block .bh.blue{color:var(--brand)}
.block .bb{white-space:pre-wrap;color:var(--ink);font-size:14px}
.block .empty{color:var(--sub);font-size:14px}
.share{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:12px 14px;margin-bottom:12px}
.share .sh{font-size:14px;font-weight:700;color:var(--brand2);margin-bottom:4px}
.share .sa{font-size:12px;color:var(--sub);margin-bottom:6px}
.share .sc{white-space:pre-wrap;color:var(--ink);font-size:14px}
.share .ops{margin-top:8px;display:flex;gap:6px}
.more{text-align:center;margin-top:6px}
.detail-ops{margin-top:6px;display:flex;gap:6px;flex-wrap:wrap}

/* ---------- 讲师管理 ---------- */
.tr-row{display:flex;align-items:center;gap:8px;padding:8px 0;border-bottom:1px solid var(--line)}
.tr-row:last-child{border-bottom:none}
.tr-name{flex:1;font-size:14px;color:var(--ink)}
.tr-count{font-size:13px;color:var(--sub);min-width:36px;text-align:right}

/* ---------- 学员分享汇总 ---------- */
.stu-list{display:flex;flex-direction:column;gap:16px}
.stu-block{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:14px}
.stu-head{font-size:16px;font-weight:700;color:var(--brand2);margin-bottom:10px;padding-bottom:6px;border-bottom:1px solid var(--line)}

/* ---------- 模态框 ---------- */
.modal{position:fixed;inset:0;background:rgba(16,24,40,.45);display:flex;
  align-items:center;justify-content:center;z-index:50;padding:20px}
.modal[hidden]{display:none}
.modal-box{background:#fff;border-radius:14px;width:min(560px,100%);max-height:88vh;overflow:auto;padding:20px 22px}
.modal-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:14px}
.modal-head span{font-size:17px;font-weight:800;color:var(--brand2)}
.modal-head .x{border:none;background:none;font-size:24px;cursor:pointer;color:var(--sub);line-height:1}
.fld{margin-bottom:14px}
.fld label{display:block;font-size:13px;color:var(--sub);margin-bottom:5px}
.fld input,.fld textarea,.fld select{width:100%;border:1px solid var(--line);border-radius:8px;
  padding:9px 11px;font-size:14px;font-family:inherit;color:var(--ink);background:var(--card)}
.fld textarea{min-height:90px;resize:vertical}
.modal-ops{display:flex;gap:10px;justify-content:flex-end;margin-top:6px}