:root{--bg: #f3f4f6;--surface: #ffffff;--border: #e5e7eb;--text: #111827;--dim: #6b7280;--primary: #2563eb;--word: #2b579a;--ppt: #c43e1c}*{box-sizing:border-box}body{margin:0;font-family:Segoe UI,system-ui,-apple-system,sans-serif;background:var(--bg);color:var(--text)}.app{max-width:1200px;margin:0 auto;padding:16px}.topbar{display:flex;justify-content:space-between;align-items:center;margin-bottom:16px}.brand{display:flex;gap:12px;align-items:center}.logo{font-size:34px}.topbar h1{margin:0;font-size:20px}.topbar p{margin:2px 0 0;font-size:13px;color:var(--dim)}.layout{display:grid;grid-template-columns:380px 1fr;gap:16px;align-items:start}@media (max-width: 900px){.layout{grid-template-columns:1fr}}.card{background:var(--surface);border:1px solid var(--border);border-radius:14px;padding:18px;margin-bottom:16px}.card h2{margin:0 0 14px;font-size:16px}.field{margin-bottom:12px}.row{display:flex;gap:12px}.row .field{flex:1}label{display:block;font-size:13px;font-weight:600;margin-bottom:5px;color:#374151}input,select,textarea{width:100%;padding:10px 12px;border:1px solid var(--border);border-radius:9px;font-size:14px;font-family:inherit;background:#fff}input:focus,select:focus,textarea:focus{outline:2px solid var(--primary);border-color:var(--primary)}textarea{resize:vertical}.btn{border:none;border-radius:9px;padding:10px 16px;font-size:14px;font-weight:600;cursor:pointer;background:#e5e7eb;color:#111827}.btn:hover{filter:brightness(.97)}.btn:disabled{opacity:.6;cursor:default}.btn.primary{background:var(--primary);color:#fff}.btn.ghost{background:transparent;border:1px solid var(--border)}.btn.big{width:100%;padding:13px;font-size:15px;margin-top:4px}.btn.word{background:var(--word);color:#fff}.btn.ppt{background:var(--ppt);color:#fff}.settings label{margin-top:6px}.settings a{color:var(--primary);word-break:break-all}.badge-free{display:inline-block;background:#16a34a;color:#fff;font-size:10.5px;font-weight:700;padding:1px 7px;border-radius:20px;margin-left:6px;vertical-align:middle}.hint{font-size:12px;color:var(--dim);margin:8px 0}.error{color:#dc2626;font-size:13px;margin-top:10px}.empty{text-align:center;padding:60px 20px;color:var(--dim)}.big-emoji{font-size:48px;display:block;margin-bottom:12px}.spin{animation:spin 1.5s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.actions{display:flex;gap:10px;margin-bottom:16px;flex-wrap:wrap}.preview{font-size:14px;line-height:1.55}.ga-title{text-align:center;margin:0;font-size:18px}.ga-sub{text-align:center;color:var(--dim);margin:4px 0 14px;font-weight:600}.preview h3{margin:18px 0 8px;color:var(--primary);font-size:15px;border-bottom:2px solid var(--border);padding-bottom:4px}.preview h4{margin:12px 0 6px;font-size:14px}.preview ul{margin:4px 0 4px 4px;padding-left:20px}.preview li{margin-bottom:3px}.group-label{font-weight:600;margin:8px 0 2px}.hoatdong{background:#f9fafb;border:1px solid var(--border);border-radius:10px;padding:12px;margin-bottom:10px}.hd-th{margin-bottom:14px}.hd-th h4{margin:10px 0 6px}.hd-table{width:100%;border-collapse:collapse;font-size:13.5px}.hd-table th,.hd-table td{border:1px solid var(--border);padding:8px 10px;vertical-align:top;text-align:left}.hd-table th{background:#eef2ff;width:50%}.hd-table ul{margin:0;padding-left:18px}.hd-table li{margin-bottom:4px}.dieuchinh{color:var(--dim);font-style:italic}.slides{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:10px}.slide-card{border:1px solid var(--border);border-radius:10px;overflow:hidden;font-size:12.5px}.slide-head{background:var(--primary);color:#fff;padding:8px 10px;font-weight:600}.slide-card ul{margin:8px 0;padding-left:22px}.foot{text-align:center;color:var(--dim);font-size:12px;margin:20px 0}.tabs{display:flex;gap:8px;margin-bottom:16px;border-bottom:2px solid var(--border)}.tab{border:none;background:transparent;padding:10px 18px;font-size:15px;font-weight:600;cursor:pointer;color:var(--dim);border-bottom:3px solid transparent;margin-bottom:-2px}.tab:hover{color:var(--text)}.tab.active{color:var(--primary);border-bottom-color:var(--primary)}.btn.game-cta{background:#7c3aed;color:#fff}.btn.dethi-cta{background:#0891b2;color:#fff}.btn.print{background:#0f766e;color:#fff}.dethi .matran{border-collapse:collapse;width:100%;margin:4px 0 12px;font-size:13.5px}.dethi .matran th,.dethi .matran td{border:1px solid var(--border);padding:6px 10px;text-align:center}.dethi .matran th{background:#f3f4f6}.dethi .matran td:first-child,.dethi .matran th:first-child{text-align:left}.dethi .matran tr.tong td{font-weight:700;background:#f9fafb}.dethi .cau{margin:10px 0;padding-bottom:8px;border-bottom:1px dashed var(--border)}.dethi .cau-de{line-height:1.5}.dethi .chip{font-size:11px;background:#ecfeff;color:#0e7490;padding:1px 8px;border-radius:20px;white-space:nowrap}.dethi .luachon{margin:6px 0 0 18px;display:grid;gap:3px}.dethi .lc.dung{color:#047857;font-weight:600}.dethi .dapan{margin:6px 0 0 18px;font-size:13.5px;background:#f0fdf4;border-left:3px solid #16a34a;padding:6px 10px;border-radius:6px}.gl-title{margin:6px 0 2px;font-size:17px}.gl-sub{color:var(--dim);margin:0 0 14px;font-size:13.5px}.game-cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:14px}.game-card{border:1px solid var(--border);border-radius:12px;padding:14px;background:#fff;display:flex;flex-direction:column}.gc-head{display:flex;gap:10px;align-items:flex-start}.gc-icon{font-size:28px}.gc-head h3{margin:0;font-size:15px}.gc-type{font-size:12px;color:var(--dim)}.gc-desc{font-size:13.5px;margin:10px 0 8px;flex:1}.tags{display:flex;flex-wrap:wrap;gap:5px;margin-bottom:8px}.tag{font-size:11.5px;padding:2px 8px;border-radius:20px;background:#eef2ff;color:#4338ca}.gc-disc{font-size:12.5px;background:#f9fafb;border:1px solid var(--border);border-radius:8px;padding:7px 9px;margin:0 0 10px}.gc-rules{font-size:13px;margin-bottom:10px}.gc-rules summary{cursor:pointer;font-weight:600;color:var(--primary)}.gc-rules ol{margin:6px 0;padding-left:20px}.stage{position:fixed;top:0;right:0;bottom:0;left:0;z-index:50;background:#0f172a;color:#fff;display:flex;flex-direction:column}.stage-bar{display:flex;justify-content:space-between;align-items:center;padding:12px 20px;background:#1e293b}.stage-title{font-size:18px;font-weight:700}.btn.ghost.light{color:#fff;border-color:#475569}.stage-body{flex:1;display:flex;align-items:center;justify-content:center;padding:24px;overflow:auto}.play{width:100%;max-width:900px;text-align:center}.q-big{font-size:clamp(22px,4vw,40px);font-weight:700;margin-bottom:28px;line-height:1.35}.options{display:grid;grid-template-columns:1fr 1fr;gap:14px}.options.ds{grid-template-columns:1fr 1fr;max-width:620px;margin:0 auto}.option{border:2px solid #475569;background:#1e293b;color:#fff;border-radius:14px;padding:18px 20px;font-size:clamp(16px,2.4vw,24px);font-weight:600;cursor:pointer;text-align:left;transition:transform .1s,background .2s}.option:hover{transform:translateY(-2px);background:#334155}.opt-key{display:inline-block;width:34px;height:34px;line-height:34px;text-align:center;border-radius:50%;background:#475569;margin-right:10px;font-weight:800}.option.right{background:#16a34a;border-color:#22c55e}.option.wrong{background:#dc2626;border-color:#ef4444}.option.faded{opacity:.45}.option.ds-d{background:#16a34a;border-color:#22c55e;text-align:center}.option.ds-s{background:#dc2626;border-color:#ef4444;text-align:center}.reveal{margin-top:22px;font-size:clamp(15px,2vw,20px);background:#1e293b;border-radius:12px;padding:14px 18px}.big-reveal{font-size:clamp(20px,3vw,30px);font-weight:700;background:#7c3aed}.ds-result{font-size:clamp(24px,4vw,40px);font-weight:800;margin-top:10px}.ds-result.is-true{color:#4ade80}.ds-result.is-false{color:#f87171}.nav{display:flex;align-items:center;justify-content:center;gap:20px;margin-top:34px}.nav .btn{background:#334155;color:#fff;padding:10px 22px}.nav .btn:disabled{opacity:.4}.nav-count{font-size:18px;font-weight:700;min-width:70px}.flip{width:min(560px,80vw);height:300px;margin:0 auto;perspective:1200px;cursor:pointer}.flip-inner{position:relative;width:100%;height:100%;transition:transform .5s;transform-style:preserve-3d}.flip.is-flipped .flip-inner{transform:rotateY(180deg)}.flip-face{position:absolute;top:0;right:0;bottom:0;left:0;backface-visibility:hidden;border-radius:18px;display:flex;align-items:center;justify-content:center;padding:24px;font-size:clamp(20px,3vw,32px);font-weight:700;text-align:center}.flip-face.front{background:#1d4ed8}.flip-face.back{background:#7c3aed;transform:rotateY(180deg)}.wheel-play{display:flex;flex-direction:column;align-items:center;gap:20px}.wheel-wrap{position:relative;width:min(360px,72vw);height:min(360px,72vw)}.wheel-pointer{position:absolute;top:-14px;left:50%;transform:translate(-50%);font-size:34px;color:#fbbf24;z-index:2}.wheel{width:100%;height:100%;border-radius:50%;border:8px solid #fbbf24;position:relative}.wheel-num{position:absolute;top:50%;left:50%;font-weight:800;font-size:18px;color:#fff;transform-origin:0 0}.dt-hint{font-size:clamp(16px,2.4vw,24px);margin-bottom:24px}.dt-word{display:flex;flex-wrap:wrap;justify-content:center;gap:10px;margin-bottom:26px}.dt-cell{width:54px;height:64px;border-radius:10px;background:#1e293b;border:2px solid #475569;display:flex;align-items:center;justify-content:center;font-size:30px;font-weight:800}.dt-cell.open{background:#16a34a;border-color:#22c55e}.dt-cell.space{background:transparent;border:none;width:20px}.dt-actions{display:flex;gap:14px;justify-content:center}.dt-actions .btn{background:#334155;color:#fff;padding:12px 22px;font-size:16px}.dt-actions .btn.primary{background:var(--primary)}.hint.light{color:#94a3b8}@media (max-width: 640px){.options{grid-template-columns:1fr}}