/* ============================================================
   HƯỚNG DẪN TẠI CHỖ — "Vừa dùng vừa học"
   Khối accordion 3 phần gắn ở đầu mỗi tab/module (admin + Khu Học Tập)
   trithuc.pro.vn (Tải Sản Phẩm Số)
   ============================================================ */
.vdvh-wrap{margin:0 0 18px 0;border-radius:14px;overflow:hidden;
  box-shadow:0 2px 10px rgba(30,41,59,.08);border:1px solid #e7ebf3;background:#fff}
.vdvh-head{display:flex;align-items:center;gap:10px;cursor:pointer;user-select:none;
  padding:12px 16px;font-weight:800;font-size:15px;color:#fff;
  background:linear-gradient(90deg,#6d5cf6 0%,#8b5cf6 45%,#4f8cf7 100%)}
.vdvh-head .vdvh-ico{font-size:16px}
.vdvh-head .vdvh-caret{margin-left:auto;transition:transform .25s ease;font-size:14px;opacity:.95}
.vdvh-wrap.closed .vdvh-head .vdvh-caret{transform:rotate(-90deg)}
.vdvh-body{padding:12px 14px 6px 14px;background:#fbfcff}
.vdvh-wrap.closed .vdvh-body{display:none}

/* Mỗi mục accordion con */
.vdvh-item{border:1px solid #e9edf6;border-radius:10px;margin-bottom:10px;overflow:hidden;background:#fff}
.vdvh-item:last-child{margin-bottom:4px}
.vdvh-item-h{display:flex;align-items:center;gap:10px;cursor:pointer;user-select:none;
  padding:11px 14px;font-weight:700;font-size:14px;color:#1e293b}
.vdvh-item-h .vdvh-num{display:inline-flex;align-items:center;justify-content:center;
  width:22px;height:22px;border-radius:6px;font-size:12px;font-weight:800;color:#fff;flex:0 0 auto}
.vdvh-item-h .vdvh-caret2{margin-left:auto;transition:transform .25s ease;color:#94a3b8;font-size:13px}
.vdvh-item.closed .vdvh-item-h .vdvh-caret2{transform:rotate(-90deg)}
.vdvh-item-b{padding:4px 16px 14px 46px;font-size:14px;line-height:1.72;color:#334155}
.vdvh-item.closed .vdvh-item-b{display:none}
.vdvh-item-b p{margin:0 0 8px 0}
.vdvh-item-b ol,.vdvh-item-b ul{margin:4px 0 8px 0;padding-left:20px}
.vdvh-item-b li{margin-bottom:7px}
.vdvh-item-b b{color:#0f172a}
.vdvh-item-b .vdvh-tip{display:block;margin-top:8px;padding:9px 12px;border-radius:8px;
  background:#f0f7ff;border-left:3px solid #4f8cf7;color:#1e3a8a;font-size:13px}

/* màu cho 3 mục */
.vdvh-item.g1 .vdvh-num{background:#6366f1}
.vdvh-item.g1{border-color:#e0e3fb}
.vdvh-item.g1 .vdvh-item-h{background:#f3f4ff}
.vdvh-item.g2 .vdvh-num{background:#0ea5e9}
.vdvh-item.g2{border-color:#d7eefb}
.vdvh-item.g2 .vdvh-item-h{background:#eef9ff}
.vdvh-item.g3 .vdvh-num{background:#10b981}
.vdvh-item.g3{border-color:#d2f1e5}
.vdvh-item.g3 .vdvh-item-h{background:#edfbf5}

@media (max-width:640px){
  .vdvh-item-b{padding-left:16px}
  .vdvh-head{font-size:14px}
}