/* ============ HỌC VUI — GIAO DIỆN CHUNG ============ */
*{box-sizing:border-box;margin:0;padding:0}
:root{
  --green:#5a9e2f;--green-d:#2f6b1f;--green-l:#eaf4de;
  --orange:#f0a63a;--red:#d9534f;--blue:#3a87c8;
  --bg:#f2f7ec;--card:#fff;--text:#2b3a22;--muted:#7a8a6a;
  --radius:14px;--shadow:0 2px 10px rgba(40,70,20,.10);
}
body{font-family:'Segoe UI','Trebuchet MS',Tahoma,sans-serif;background:var(--bg);color:var(--text);min-height:100vh}
a{color:var(--green-d);text-decoration:none}
code{background:#eef3e6;padding:2px 6px;border-radius:6px;font-size:.92em}

/* ---------- Bố cục ---------- */
.app{display:flex;min-height:100vh}
.sidebar{width:240px;flex-shrink:0;background:linear-gradient(180deg,#2f6b1f,#1c4510);color:#fff;
  display:flex;flex-direction:column;position:sticky;top:0;height:100vh}
.side-logo{display:flex;align-items:center;gap:10px;padding:20px 18px;font-size:24px;font-weight:800;color:#fff}
.side-logo .ico{font-size:32px}
.side-menu{flex:1;overflow-y:auto;padding:6px 10px}
.side-menu a{display:flex;align-items:center;gap:11px;padding:11px 13px;margin:3px 0;border-radius:10px;
  color:#dcedc8;font-weight:600;font-size:15px;transition:background .15s}
.side-menu a:hover{background:rgba(255,255,255,.12)}
.side-menu a.active{background:var(--orange);color:#3a2a08}
.side-user{padding:14px;border-top:1px solid rgba(255,255,255,.15);font-size:14px}
.side-user .name{font-weight:700}
.side-user .role{color:#bcd8a0;font-size:12.5px;margin:2px 0 8px}
.side-user a{color:#ffd98a;font-weight:600}
.main{flex:1;min-width:0}
.topbar{background:var(--card);box-shadow:var(--shadow);padding:14px 26px;display:flex;
  justify-content:space-between;align-items:center;position:sticky;top:0;z-index:10}
.topbar h1{font-size:21px;color:var(--green-d)}
.topbar .chip{background:var(--green-l);padding:6px 14px;border-radius:20px;font-size:13.5px;font-weight:600}
.content{padding:24px 26px;max-width:1280px}

/* ---------- Thẻ / lưới ---------- */
.card{background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);padding:20px;margin-bottom:20px}
.card h2{font-size:17px;color:var(--green-d);margin-bottom:14px}
.grid{display:grid;gap:18px}
.grid-4{grid-template-columns:repeat(auto-fill,minmax(220px,1fr))}
.grid-3{grid-template-columns:repeat(auto-fill,minmax(300px,1fr))}
.grid-2{grid-template-columns:repeat(auto-fit,minmax(380px,1fr))}
.stat{background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);padding:18px;display:flex;gap:14px;align-items:center}
.stat .ico{font-size:34px;width:60px;height:60px;border-radius:14px;display:flex;align-items:center;justify-content:center;background:var(--green-l)}
.stat .num{font-size:26px;font-weight:800;color:var(--green-d)}
.stat .lbl{font-size:13px;color:var(--muted);font-weight:600}

/* ---------- Thẻ game ---------- */
.game-card{background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);overflow:hidden;
  display:flex;flex-direction:column;transition:transform .15s}
.game-card:hover{transform:translateY(-4px)}
.game-card .thumb{height:110px;display:flex;align-items:center;justify-content:center;font-size:54px}
.game-card .body{padding:14px 16px;flex:1;display:flex;flex-direction:column;gap:6px}
.game-card .body h3{font-size:16.5px}
.game-card .body p{font-size:13.5px;color:var(--muted);flex:1}
.game-card .meta{font-size:12.5px;color:var(--muted)}

/* ---------- Nút ---------- */
.btn{display:inline-block;background:var(--green);color:#fff;border:0;padding:9px 18px;border-radius:10px;
  font-size:14.5px;font-weight:700;cursor:pointer;font-family:inherit;transition:filter .15s}
.btn:hover{filter:brightness(1.08)}
.btn-lg{padding:12px 22px;font-size:16px}
.btn-sm{padding:5px 11px;font-size:13px;border-radius:8px}
.btn-orange{background:var(--orange);color:#3a2a08}
.btn-red{background:var(--red)}
.btn-blue{background:var(--blue)}
.btn-ghost{background:#e8efe0;color:var(--green-d)}

/* ---------- Bảng ---------- */
table{width:100%;border-collapse:collapse;font-size:14px}
th{background:var(--green-l);color:var(--green-d);text-align:left;padding:10px 12px;font-size:13px;text-transform:uppercase;letter-spacing:.4px}
td{padding:10px 12px;border-bottom:1px solid #edf2e6}
tr:hover td{background:#f8fbf4}
th:first-child{border-radius:8px 0 0 8px}
th:last-child{border-radius:0 8px 8px 0}

/* ---------- Form ---------- */
label{display:block;font-size:13.5px;font-weight:700;color:var(--green-d);margin:12px 0 5px}
input[type=text],input[type=password],input[type=number],select,textarea{
  width:100%;padding:10px 12px;border:2px solid #d8e4c8;border-radius:10px;font-size:14.5px;
  font-family:inherit;background:#fdfffb;transition:border .15s}
input:focus,select:focus,textarea:focus{outline:0;border-color:var(--green)}
.form-row{display:flex;gap:14px;flex-wrap:wrap}
.form-row>div{flex:1;min-width:150px}
.inline-form{display:inline}

/* ---------- Nhãn, thông báo ---------- */
.badge{display:inline-block;padding:3px 10px;border-radius:12px;font-size:12px;font-weight:700}
.badge-green{background:#dff0d0;color:#2f6b1f}
.badge-blue{background:#d8eaf8;color:#1f5a8a}
.badge-red{background:#f8dcd8;color:#a02a20}
.badge-gray{background:#e8e8e0;color:#666}
.badge-gold{background:#fdf0c8;color:#8a6a10}
.flash{padding:12px 16px;border-radius:10px;margin-bottom:18px;font-weight:600;font-size:14.5px}
.flash.ok{background:#dff0d0;color:#2f6b1f;border:1px solid #b8d898}
.flash.err{background:#f8dcd8;color:#a02a20;border:1px solid #e8b0a8}
.hint{background:#fdf6e0;border:1px solid #ecd9a0;border-radius:10px;padding:12px 16px;font-size:13.5px;color:#7a5f1a;margin-bottom:18px}
.empty{text-align:center;color:var(--muted);padding:36px 10px;font-size:15px}
.medal{font-size:20px}

/* ---------- Đăng nhập ---------- */
.login-body{background:linear-gradient(135deg,#4a8a2a 0%,#2f6b1f 55%,#1c4510 100%);
  display:flex;align-items:center;justify-content:center;min-height:100vh;padding:20px}
.login-card{background:#fff;border-radius:22px;box-shadow:0 18px 50px rgba(0,0,0,.35);
  padding:38px 42px;width:100%;max-width:420px;text-align:center}
.login-logo{font-size:58px}
.login-card h1{color:var(--green-d);font-size:34px;margin:4px 0 2px}
.login-sub{color:var(--muted);margin-bottom:18px}
.login-card form{text-align:left}
.login-card .btn{margin-top:18px}
.login-hint{margin-top:20px;font-size:12.8px;color:var(--muted);background:#f6faf0;border-radius:10px;padding:12px;line-height:1.9}

/* ---------- Trang chơi game ---------- */
.play-top{background:linear-gradient(90deg,#2f6b1f,#1c4510);color:#fff;height:52px;display:flex;
  align-items:center;gap:16px;padding:0 18px}
.play-top a{color:#ffd98a;font-weight:700}
.play-top .t{font-weight:800;font-size:17px}
.play-frame{width:100%;height:calc(100vh - 52px);border:0;display:block;background:#1a2a12}

@media(max-width:820px){
  .sidebar{width:64px}
  .side-logo span,.side-menu a span.txt,.side-user{display:none}
  .side-menu a{justify-content:center}
  .content{padding:16px}
}