/* Giao diện quản trị: nền trắng, phẳng, gọn, kiểu công cụ làm việc (không áp cho màn chơi). */
body:not([data-view="play"]) {
  --c-bg: #ffffff; --c-bg-2: #f5f6f8; --c-surface: #ffffff; --c-surface-2: #f5f6f8; --c-line: #e2e5ea;
  --c-ink: #1f2937; --c-muted: #6b7280;
  --c-primary: #1f6feb; --c-primary-2: #3b82f6; --c-primary-ink: #ffffff; --c-primary-soft: #eaf1fe;
  --c-accent: #1f6feb; --c-accent-soft: #eaf1fe;
  --r-sm: 6px; --r: 8px; --r-lg: 10px; --r-xl: 12px;
  --tap: 40px; --header-h: 56px;
  --shadow-press: none;
  --shadow-card: 0 1px 2px rgba(16, 24, 40, .06);
  --stage-bg: #fff;
  background: #fff; font-size: 15px;
}
body:not([data-view="play"]) .btn { border-radius: 8px; border-width: 1px; font-weight: 600; min-height: 40px; box-shadow: none; }
body:not([data-view="play"]) .btn:hover { transform: none; filter: brightness(.97); }
body:not([data-view="play"]) .btn:active { transform: none; }
body:not([data-view="play"]) .btn-soft { background: #f1f3f6; color: var(--c-ink); }
body:not([data-view="play"]) .btn-ghost { background: #fff; border-color: var(--c-line); }
body:not([data-view="play"]) .btn-lg { min-height: 44px; font-size: 1rem; padding: 0 1.3em; }
body:not([data-view="play"]) .btn-xl { min-height: 52px; font-size: 1.05rem; border-radius: 10px; }
body:not([data-view="play"]) .btn-icon { width: 40px; }
body:not([data-view="play"]) .chip, body:not([data-view="play"]) .kind-tabs, body:not([data-view="play"]) .kind-tabs button, body:not([data-view="play"]) .search input { border-radius: 8px; }
body:not([data-view="play"]) .chip { border-width: 1px; min-height: 34px; font-weight: 500; }
body:not([data-view="play"]) .app-header { background: #fff; border-bottom: 1px solid var(--c-line); box-shadow: none; }
body:not([data-view="play"]) .panel, body:not([data-view="play"]) .act-card, body:not([data-view="play"]) .modal, body:not([data-view="play"]) .empty { border: 1px solid var(--c-line); box-shadow: none; }
body:not([data-view="play"]) .act-card:hover { transform: none; border-color: #c5ccd6; box-shadow: 0 2px 8px rgba(16, 24, 40, .08); }
body:not([data-view="play"]) .empty { border-style: dashed; }
body:not([data-view="play"]) .side-item { border-radius: 8px; min-height: 38px; font-weight: 500; }
body:not([data-view="play"]) .side-item[aria-current="true"] { background: var(--c-primary-soft); color: #1347a0; box-shadow: none; font-weight: 700; }
body:not([data-view="play"]) .input, body:not([data-view="play"]) input:not([type=checkbox]):not([type=radio]), body:not([data-view="play"]) select, body:not([data-view="play"]) textarea { border-radius: 8px; border-width: 1px; }
body:not([data-view="play"]) .badge { border-radius: 6px; font-weight: 600; }
body:not([data-view="play"]) .tabbar { background: #fff; border: 0; border-top: 1px solid var(--c-line); box-shadow: none; border-radius: 0; }
body:not([data-view="play"]) h1, body:not([data-view="play"]) h2 { font-weight: 700; letter-spacing: -.01em; }

/* ---- nút nhỏ gọn (v2) ---- */
body:not([data-view="play"]) { --tap: 32px; font-size: 14px; }
body:not([data-view="play"]) .btn { min-height: 32px; padding: 0 .85em; font-size: .875rem; gap: .4em; border-radius: 6px; }
body:not([data-view="play"]) .btn svg { width: 16px; height: 16px; }
body:not([data-view="play"]) .btn-icon { width: 32px; min-width: 32px; padding: 0; }
body:not([data-view="play"]) .btn-lg { min-height: 36px; font-size: .9rem; padding: 0 1.1em; }
body:not([data-view="play"]) .btn-xl { min-height: 40px; font-size: .95rem; padding: 0 1.4em; border-radius: 8px; }
body:not([data-view="play"]) .btn-block { min-height: 36px; }
body:not([data-view="play"]) .chip { min-height: 30px; font-size: .85rem; padding: 0 .8em; }
body:not([data-view="play"]) .kind-tabs button { min-height: 30px; font-size: .85rem; padding: 0 .9em; }
body:not([data-view="play"]) .input, body:not([data-view="play"]) input:not([type=checkbox]):not([type=radio]), body:not([data-view="play"]) select { min-height: 36px; padding-top: 0; padding-bottom: 0; font-size: .9rem; }
body:not([data-view="play"]) .app-header .btn-icon { width: 32px; height: 32px; }
body:not([data-view="play"]) .app-header img, body:not([data-view="play"]) .app-header .logo img { max-height: 36px; width: auto; }
body:not([data-view="play"]) .act-actions .btn { min-height: 30px; }
body:not([data-view="play"]) .tabbar { display: none; }
@media (max-width: 760px) { body:not([data-view="play"]) .tabbar { display: flex; } body:not([data-view="play"]) .tabbar .tab, body:not([data-view="play"]) .tabbar a { font-size: .7rem; } }

/* ---- bố cục gọn (v3) ---- */
body:not([data-view="play"]) .page-head { margin-bottom: 16px; align-items: center; }
body:not([data-view="play"]) .page-head h1 { font-size: 1.5rem; font-weight: 700; }
body:not([data-view="play"]) .page-head .sub { font-size: .875rem; margin-top: 2px; }
body:not([data-view="play"]) .act-thumb { background: #f3f4f6; }
body:not([data-view="play"]) .act-thumb .play-badge { width: 32px; height: 32px; inset: auto 8px 8px auto; box-shadow: none; opacity: .92; }
body:not([data-view="play"]) .act-thumb .play-badge svg { width: 14px; height: 14px; }
body:not([data-view="play"]) .act-body { padding: 10px 12px 4px; }
body:not([data-view="play"]) .act-title { font-size: .95rem; font-weight: 600; }
body:not([data-view="play"]) .act-actions { padding: 8px 12px 12px; gap: 6px; flex-wrap: nowrap; }
body:not([data-view="play"]) .act-meta { font-size: .8rem; gap: 6px; }
body:not([data-view="play"]) .grid, body:not([data-view="play"]) .act-grid { gap: 14px; }
body:not([data-view="play"]) .qk-card { background: #fff; border: 1px solid var(--c-line); box-shadow: none; padding: 12px 14px; margin-bottom: 14px; }
body:not([data-view="play"]) .qk-card-head { display: flex; align-items: baseline; gap: 10px; flex-wrap: wrap; }
body:not([data-view="play"]) .qk-card-head h2 { font-size: 1rem; font-weight: 700; }
body:not([data-view="play"]) .qk-card-head p { margin: 0 0 8px; font-size: .82rem; flex-basis: 100%; }
body:not([data-view="play"]) .qk-card-btns { gap: 8px; }
body:not([data-view="play"]) .qk-card-btn { grid-template-columns: auto 1fr; justify-items: start; align-items: center; column-gap: 10px; padding: 8px 10px; border: 1px solid var(--c-line); box-shadow: none; border-radius: 8px; text-align: left; }
body:not([data-view="play"]) .qk-card-btn small { grid-column: 2; }
body:not([data-view="play"]) .qk-card-btn b { grid-column: 2; font-size: .9rem; }
body:not([data-view="play"]) .qk-card-btn:hover { transform: none; background: #f5f6f8; }
body:not([data-view="play"]) .qk-card-ic { grid-row: 1 / span 2; width: 32px; height: 32px; border-radius: 8px; }
body:not([data-view="play"]) .qk-card-ic .icon { width: 18px; height: 18px; }

/* ---- màn chơi dạng cửa sổ: cùng bảng màu trắng/xanh dịu, nút vẫn to cho học sinh ---- */
body[data-view="play"][data-playmode="window"] {
  --c-bg: #fff; --c-bg-2: #f5f6f8; --c-surface: #fff; --c-surface-2: #f5f6f8; --c-line: #e2e5ea;
  --c-ink: #1f2937; --c-muted: #6b7280;
  --c-primary: #1f6feb; --c-primary-2: #3b82f6; --c-primary-soft: #eaf1fe; --c-accent: #7c3aed; --c-accent-soft: #f1ebff;
  --stage-bg: #f5f7fa; --header-h: 56px;
}
body[data-view="play"][data-playmode="window"] .app-header { background: #fff; border-bottom: 1px solid var(--c-line); box-shadow: none; }
body[data-view="play"][data-playmode="window"] .app-header .btn { min-height: 32px; border-radius: 6px; font-size: .875rem; box-shadow: none; }
body[data-view="play"][data-playmode="window"] .app-header .btn-icon { width: 32px; }
body[data-view="play"][data-playmode="window"] .btn-primary { box-shadow: none; }
body[data-view="play"][data-playmode="window"] .game { background: #f5f7fa; }
body[data-view="play"][data-playmode="window"] .tabbar { display: none; }
body[data-view="play"] .switch-strip { width: min(100%, 1280px); margin: 16px auto 24px; }
body[data-view="play"] .switch-strip h3 { font-size: .95rem; font-weight: 700; margin-bottom: 10px; }
body[data-view="play"] .switch-list { display: flex; gap: 10px; overflow-x: auto; padding-bottom: 6px; }
body[data-view="play"] .switch-item { flex: none; width: 120px; display: grid; gap: 6px; padding: 6px; border: 1px solid var(--c-line); border-radius: 8px; background: #fff; cursor: pointer; font: inherit; color: inherit; text-align: center; }
body[data-view="play"] .switch-item[aria-current="true"] { border-color: #1f6feb; box-shadow: 0 0 0 2px #cfe0fc; }
body[data-view="play"] .switch-item:hover { background: #f5f6f8; }
body[data-view="play"] .switch-thumb { display: block; aspect-ratio: 16/10; background: #f3f4f6; border-radius: 6px; overflow: hidden; }
body[data-view="play"] .switch-thumb svg { width: 100%; height: 100%; }
body[data-view="play"] .switch-name { font-size: .78rem; font-weight: 600; line-height: 1.2; }
body[data-view="play"][data-playmode="full"] .switch-strip { display: none; }
body:not([data-view="play"]) .qk-card-btn { align-content: center; row-gap: 0; }

/* Anagram trong khung cửa sổ: thu nhỏ để không phải cuộn (cỡ ô theo --ts, khay chữ co theo) */
body[data-view="play"][data-playmode="window"] .ta{gap:clamp(8px,1.6vh,18px)}
body[data-view="play"][data-playmode="window"] .ta .ta-q img{max-height:min(17vh,170px)}
body[data-view="play"][data-playmode="window"] .ta .ta-q{padding:10px 16px;gap:6px}
body[data-view="play"][data-playmode="window"] .ta .ta-q h2{font-size:clamp(1.05rem,.8rem + 1.1vw,2rem)}
body[data-view="play"][data-playmode="window"] .ta .ta-area{--ts:clamp(38px,min(8.5vh,calc(80vw / (var(--n,8) + 1))),80px);gap:clamp(8px,1.6vh,18px)}
body[data-view="play"][data-playmode="window"] .ta .ta-bank{min-height:calc(var(--ts) * 1.18 + 20px);padding:8px}
@media (max-height:780px){body[data-view="play"][data-playmode="window"] .ta .ta-q img{max-height:12vh}body[data-view="play"][data-playmode="window"] .ta .ta-tries{min-height:1.2em}}
@media (max-width:600px){body[data-view="play"][data-playmode="window"] .ta .ta-actions{gap:6px;padding-top:0}body[data-view="play"][data-playmode="window"] .ta .ta-actions .btn{min-height:44px;padding:0 .75em;font-size:.85rem}}

/* ===== Kiểu nền trò chơi: hiện đại / cổ điển / sáng tạo (chỉ đổi nền, phông, bo góc; bộ đề/ảnh/voice giữ nguyên) ===== */
.style-picker { display: flex; gap: .5rem; flex-wrap: wrap; }
.style-opt { display: flex; align-items: center; gap: .5rem; padding: .35rem .7rem .35rem .35rem; border: 2px solid var(--c-line); border-radius: 999px; background: #fff; font: inherit; font-weight: 700; cursor: pointer; }
.style-opt[aria-pressed="true"] { border-color: var(--c-primary); box-shadow: 0 0 0 3px var(--c-primary-soft); }
.style-sw { width: 28px; height: 28px; border-radius: 8px; display: block; border: 1px solid rgba(0,0,0,.12); }
.style-sw[data-style="modern"] { background: linear-gradient(135deg, #fff 0 50%, #eef2f7 50%); }
.style-sw[data-style="classic"] { background: radial-gradient(circle at 30% 30%, #fbf3dc, #e6d3a3); border-radius: 4px; }
.style-sw[data-style="creative"] { background: conic-gradient(from 20deg, #ff6b2c, #f43f8e, #8b5cf6, #0fa89b, #ffcf3d, #ff6b2c); border-radius: 50%; }

/* hiện đại: sạch, phẳng, nền sáng, bo vừa (mặc định) */
.game[data-style="modern"], body[data-view="play"][data-playmode="window"] .game[data-style="modern"] { --r: 14px; --r-lg: 20px; }

/* cổ điển: giấy kem, chữ có chân, viền mảnh, bóng nhẹ như bảng đen/sổ tay */
.game[data-style="classic"], body[data-view="play"][data-playmode="window"] .game[data-style="classic"] {
  --font: "HV Playfair", "Be Vietnam Pro", "Noto Serif", serif; font-family: var(--font);
  --c-bg: #f6efdc; --c-surface: #fffaf0; --c-surface-2: #f3e8cc; --c-line: #d9c79b; --c-ink: #3a2a14; --c-muted: #7a6544;
  --r-sm: 4px; --r: 6px; --r-lg: 8px; --r-xl: 10px;
  --shadow-card: 0 1px 0 #d9c79b, 0 6px 14px -8px rgba(80,55,15,.35); --shadow-press: 0 3px 0 rgba(80,55,15,.28);
  background: radial-gradient(ellipse at 50% 0, #fdf6e3 0, transparent 70%), repeating-linear-gradient(0deg, rgba(120,90,40,.035) 0 2px, transparent 2px 5px), #f1e7cb;
}
.game[data-style="classic"] .game-bar .btn-icon, .game[data-style="classic"] .pill { border: 1px solid var(--c-line); }
.game[data-style="classic"] .game-stage { border-top: 2px double #c9b27a; }

/* sáng tạo: màu nổi, hình khối vui, bo tròn lớn, phông tròn */
.game[data-style="creative"], body[data-view="play"][data-playmode="window"] .game[data-style="creative"] {
  --font: ui-rounded, "Nunito", "Trebuchet MS", "Be Vietnam Pro", sans-serif; font-family: var(--font);
  --r-sm: 16px; --r: 24px; --r-lg: 32px; --r-xl: 40px;
  --shadow-card: 0 3px 0 rgba(34,22,58,.18), 0 14px 26px -12px rgba(34,22,58,.3); --shadow-press: 0 6px 0 rgba(34,22,58,.22);
  background:
    radial-gradient(circle at 8% 12%, rgba(255,207,61,.55) 0 3.5%, transparent 3.7%),
    radial-gradient(circle at 92% 18%, rgba(244,63,142,.35) 0 4.5%, transparent 4.7%),
    radial-gradient(circle at 85% 88%, rgba(15,168,155,.38) 0 5.5%, transparent 5.7%),
    radial-gradient(circle at 12% 90%, rgba(139,92,246,.32) 0 4%, transparent 4.2%),
    linear-gradient(160deg, #fff4e2, #ffe6f2 55%, #e6f6ff);
}
.game[data-style="creative"] .game-title { transform: rotate(-1deg); }
.game[data-style="creative"] .game-bar .btn-icon, .game[data-style="creative"] .pill { border: 2px solid var(--c-ink); box-shadow: 0 3px 0 var(--c-ink); }

/* ===== Menu footer gọn (điện thoại): 5 mục đều nhau, thấp, nhãn 1 dòng, mục đang chọn có gạch trên ===== */
@media (max-width: 760px) {
  body:not([data-view="play"]) .tabbar { left: 0; right: 0; bottom: 0; max-width: none; display: grid; grid-auto-flow: column; grid-auto-columns: 1fr; gap: 0; padding: 0 4px env(safe-area-inset-bottom); background: rgba(255,255,255,.96); backdrop-filter: blur(14px); border-top: 1px solid var(--c-line); box-shadow: 0 -4px 14px -8px rgba(20,30,60,.25); }
  body:not([data-view="play"]) .tabbar .tab { position: relative; min-height: 50px; padding: 6px 2px 5px; gap: 2px; border-radius: 0; background: none; font-size: .64rem; font-weight: 600; letter-spacing: 0; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; color: #6b7690; }
  body:not([data-view="play"]) .tabbar .tab .tab-ic svg { width: 21px; height: 21px; }
  body:not([data-view="play"]) .tabbar .tab[aria-current="page"] { background: none; color: var(--c-primary); }
  body:not([data-view="play"]) .tabbar .tab[aria-current="page"]::before { content: ""; position: absolute; top: 0; left: 28%; right: 28%; height: 3px; border-radius: 0 0 3px 3px; background: var(--c-primary); }
  body:not([data-view="play"]) .tabbar .tab-main .tab-ic { display: grid; place-items: center; width: 30px; height: 30px; margin-top: -2px; border-radius: 50%; background: var(--c-primary); color: #fff; }
  body:not([data-view="play"]) .tabbar .tab-main .tab-ic svg { width: 18px; height: 18px; }
  body:not([data-view="play"]) .app-main { padding-bottom: calc(64px + env(safe-area-inset-bottom)); }
}

/* Cổng UI mobile (02/11): nút «Bỏ qua tới nội dung» = skip link đủ cỡ, chỉ hiện khi focus; logo + thẻ đăng nhập/vào lớp đủ vùng chạm 44px */
button.sr-only { position: fixed; left: 8px; top: 8px; width: auto; height: auto; min-height: 44px; padding: 0 16px; margin: 0; clip: auto; clip-path: none; overflow: visible; white-space: nowrap; border: 0; border-radius: 10px; background: var(--c-surface, #fff); color: inherit; font-weight: 700; z-index: 1000; transform: translateY(-200%); visibility: hidden; opacity: 0; pointer-events: none; }
button.sr-only:focus-visible { visibility: visible; opacity: 1; pointer-events: auto; transform: none; outline: 3px solid var(--c-primary, #f60); }
@media (max-width: 560px), (pointer: coarse) {
  .app-header .brand { min-height: 44px; display: inline-flex; align-items: center; }
  body:not([data-view="play"]) .auth-card .btn, body:not([data-view="play"]) .auth-card input:not([type=checkbox]):not([type=radio]), body:not([data-view="play"]) .auth-card select { min-height: 44px; }
}