@import"https://fonts.googleapis.com/css2?family=Be+Vietnam+Pro:ital,wght@0,400;0,500;0,600;0,700;0,800;1,400&display=swap";[data-xq-theme=site]{--app: #f6f1ea;--panel: #fffdf9;--phead: #efe7db;--side: #f1eae0;--field: #ffffff;--ink: #2a2318;--muted: #6a5f50;--line: rgba(42, 35, 24, .15);--rule: rgba(42, 35, 24, .36);--selrow: #f5e7cd;--sideact: #f2e3c6;--chip: #ece3d5;--accent: #c8913a;--accent-dark: #a97724;--accent-soft: #f2e3c6;--oninv: #2a2318;--pos: #14743c;--neg: #3a4fa8;--run: #1f8a4c;--ready: #6a5f50;--err: #9c2b16;--ben-do-thong-ke: #9c2b16;--wood: #d4a46c;--wood-2: #dcb078;--font: "Be Vietnam Pro", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;--mono: ui-monospace, "SF Mono", Menlo, monospace;--tx: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='140' height='140' filter='url(%23n)' opacity='0.055'/%3E%3C/svg%3E")}html,body{margin:0;padding:0}.xq-page{background:var(--app);color:var(--ink);font-family:var(--font);font-size:13px;line-height:1.4;font-variant-numeric:tabular-nums;-webkit-font-smoothing:antialiased}.xq-page *,.xq-page *:before,.xq-page *:after{box-sizing:border-box;border-radius:0}:where(.xq-page) button{font:inherit;color:inherit;background:none;border:0;padding:0;cursor:pointer}[data-xq-theme=site]{--app: #f6f1ea;--panel: #fffdf9;--phead: #efe7db;--side: #f1eae0;--field: #ffffff;--ink: #2a2318;--muted: #6a5f50;--line: rgba(42, 35, 24, .15);--rule: rgba(42, 35, 24, .36);--selrow: #f5e7cd;--sideact: #f2e3c6;--chip: #ece3d5;--accent: #c8913a;--accent-dark: #a97724;--accent-soft: #f2e3c6;--oninv: #2a2318;--pos: #14743c;--neg: #3a4fa8;--run: #1f8a4c;--ready: #6a5f50;--err: #9c2b16;--ben-do-thong-ke: #9c2b16;--wood: #d4a46c;--wood-2: #dcb078;--font: "Be Vietnam Pro", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;--mono: ui-monospace, "SF Mono", Menlo, monospace;--tx: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='140' height='140' filter='url(%23n)' opacity='0.055'/%3E%3C/svg%3E")}:root{--pt-header-h: 48px}@media (max-width: 767px){:root{--pt-header-h: 52px}}#phan-tich-root{position:fixed;top:0;right:0;bottom:0;left:0;display:flex;flex-direction:column;overflow:hidden;background:var(--app);color:var(--ink);font-family:var(--font);font-size:13px;line-height:1.4;font-variant-numeric:tabular-nums;-webkit-font-smoothing:antialiased}#phan-tich-root *,#phan-tich-root *:before,#phan-tich-root *:after,:is(#phan-tich-feedback,[data-feedback-box]),:is(#phan-tich-feedback,[data-feedback-box]) *{box-sizing:border-box;border-radius:0}#phan-tich-root button,:is(#phan-tich-feedback,[data-feedback-box]) button{font:inherit;color:inherit;background:none;border:0;padding:0;cursor:pointer}#phan-tich-root button:disabled,:is(#phan-tich-feedback,[data-feedback-box]) button:disabled{opacity:.4;cursor:not-allowed}#phan-tich-root input,#phan-tich-root textarea,:is(#phan-tich-feedback,[data-feedback-box]) input,:is(#phan-tich-feedback,[data-feedback-box]) select,:is(#phan-tich-feedback,[data-feedback-box]) textarea{font:inherit;color:inherit}#phan-tich-root :focus-visible{outline:2px solid var(--accent);outline-offset:2px}#phan-tich-root .pt-nav{position:relative;z-index:300}.pt-bar{background-image:var(--tx)!important}.pt-well{background-image:radial-gradient(120% 90% at 50% 0%,rgba(42,35,24,.05),transparent 60%),var(--tx)}.pt-flat{background-image:none!important}#phan-tich-root .pt-small-btn{height:26px;padding:0 9px;font-size:12px;border:1px solid var(--line);display:flex;align-items:center;gap:5px;text-decoration:none;color:inherit}.pt-mono{font-family:var(--mono)}.pt-label{font-size:11px;font-weight:800;letter-spacing:.1em;text-transform:uppercase}.pt-num{font-family:var(--mono);font-weight:800;text-align:right}@keyframes ptPulse{0%,to{opacity:1}50%{opacity:.35}}.pt-pulse{animation:ptPulse 1.4s ease-in-out infinite}#phan-tich-root .board-top,#phan-tich-root .board-bottom{background:transparent}#phan-tich-notebook{--primary: var(--accent);--primary-dark: var(--accent-dark);--primary-soft: var(--accent-soft);--danger: var(--err);--success: var(--pos);--radius-sm: 0;--radius-md: 0;--radius-lg: 0;--shadow-sm: none;--shadow-md: none;--shadow-lg: none;--space-xs: 4px;--space-sm: 8px;--space-md: 12px;--space-lg: 16px;font-family:var(--font);color:var(--ink)}#phan-tich-notebook [hidden]{display:none!important}#phan-tich-notebook #nbDraftBar:not(:empty){position:fixed;left:50%;bottom:16px;transform:translate(-50%);z-index:150;background:var(--panel);border:2px solid var(--rule);padding:8px 12px;font-size:12.5px}.pt-main-ban>.pt-well{place-items:start center!important;padding-top:4px!important}.xv-app{position:fixed;top:0;right:0;bottom:0;left:0;display:flex;flex-direction:column;overflow:hidden;background:var(--app);color:var(--ink)}.xv-nen{display:flex;flex-direction:column;flex:1;min-height:0}.xv-main{flex:1;min-height:0;display:flex;flex-direction:column;overflow-y:auto}.xv-ssr{padding:24px;color:var(--muted)}.xv-khung{flex:1;min-height:480px;display:flex;flex-direction:column}.xv-thanh{flex:none;display:flex;align-items:center;justify-content:space-between;gap:8px;min-height:40px;padding:0 12px;border-bottom:2px solid var(--rule);background-color:var(--app)}.xv-thanh-trai{min-width:0}.xv-thanh-phai{flex:none;display:flex;align-items:center;gap:6px}.xv-than{flex:1;min-height:0;display:flex;flex-direction:row}.xv-giua,.xv-o-ban{flex:1;min-width:0;min-height:0;display:flex;flex-direction:column}.xv-o-ban .pt-well{place-items:start center!important;padding-top:4px!important}.xv-cot-trai{width:var(--xv-trai);flex:none;min-height:0;display:flex;flex-direction:column;background:var(--side);border-right:1px solid var(--line)}.xv-cot-phai{width:var(--xv-phai);flex:none;min-width:0;min-height:0;display:flex;flex-direction:column;gap:8px;padding:8px;overflow-y:auto;border-left:1px solid var(--line)}.xv-cot-nuoc{flex:1;min-height:0;display:flex;flex-direction:column}.xv-cot-nuoc-dau{flex:none;display:flex;flex-wrap:nowrap;align-items:center;gap:2px 6px;min-height:38px;padding:3px 8px;border-bottom:1px solid var(--line)}.xv-cot-nuoc-dau>button,.xv-cot-nuoc-dau .xv-ky-phap-o{flex:none}.xv-cot-nuoc-ten{margin:0;white-space:nowrap;flex:0 1 auto;min-width:0;overflow:hidden;text-overflow:ellipsis}.xv-cot-nuoc-dem{margin-left:auto;flex:none;font-size:11px;color:var(--muted);white-space:nowrap}.xv-cot-nuoc-than{flex:1;min-height:0;display:flex;flex-direction:column}.xv-cot-nuoc-than .xv-ds-nuoc{border:0;background:transparent}.xv-cot-nuoc-than>.xv-cay{padding:8px 8px 0}.xv-cot-nuoc-than>.xv-tt-cho{margin:8px}.xv-giua>.xv-trang-thai{padding:0 8px 4px}.xv-chi-tiet-vung .xv-chi-tiet{margin:0 8px 6px}.xv-dk-bar{flex:none;display:flex;flex-wrap:wrap;align-items:center;gap:2px 12px;min-height:48px;padding:2px 12px;border-top:1px solid var(--line)}.xv-dk-bar .xv-trang-thai{min-height:0;text-align:left;white-space:nowrap;font-size:12px}.xv-tien-do{flex:1 1 60px;height:2px;background:var(--line)}.xv-tien-do-day{display:block;height:100%;background:var(--accent)}.xv-trang-thai-hang{flex:none}.xv-trang-thai-hang .xv-trang-thai{text-align:center;font-size:12px}.xv-cot-ngan{padding:0;gap:0;overflow:hidden}.xv-ngan-dai{flex:none;display:flex;overflow-x:auto;background:var(--phead);border-bottom:1px solid var(--line)}.xv-ngan{flex:none;min-height:40px;padding:0 12px;font-size:12.5px;font-weight:600;color:var(--muted);background:transparent;border:0;white-space:nowrap;cursor:pointer}.xv-ngan:hover{color:var(--ink)}.xv-ngan.is-hien{font-weight:800;color:var(--oninv);background:var(--accent)}.xv-ngan:focus-visible{outline:2px solid var(--accent-dark);outline-offset:-2px}.xv-bang{flex:1;min-height:0;display:flex;flex-direction:column;gap:8px;padding:8px;overflow-y:auto}.xv-bang.is-nuoc{padding:0;overflow:hidden;background:var(--side)}.xv-bac-hep .xv-than{flex-direction:column}.xv-bac-hep .xv-giua{flex:none}.xv-bac-hep .xv-o-ban{flex:none;height:270px}.xv-bac-hep[data-co-o] .board-frame{--cell-size: var(--xv-co-o) !important}.xv-bac-hep[data-co-o] .xv-o-ban{flex:none;height:auto}.xv-bac-hep[data-co-o] .xv-o-ban .pt-well{flex:none!important;padding:8px!important}.xv-cot-ngan .xv-cot-nuoc-ten{display:none}.xv-bac-hep .xv-cot-ngan{width:auto;flex:1;border-top:1px solid var(--line);border-left:0}.xv-bac-hep .xv-cot-nuoc-dau{min-height:40px;padding:0 8px}.xv-bac-hep .xv-dk-bar{flex-wrap:nowrap;justify-content:center;min-height:56px;border-top:2px solid var(--rule)}.xv-bac-hep .xv-dk .xv-nut{min-width:44px}.xv-bac-vua .xv-cot-ngan{width:var(--xv-phai)}@media (max-height: 500px){.xv-khung{min-height:0}.xv-bac-hep .xv-than{display:grid;grid-template-columns:minmax(0,1fr) min(300px,46vw);grid-template-rows:minmax(0,1fr) auto}.xv-bac-hep .xv-giua{flex:none;min-height:0;border-right:1px solid var(--line)}.xv-bac-hep .xv-o-ban{flex:1;height:auto;min-height:0}.xv-bac-hep .xv-cot-ngan{width:auto;min-width:0;border-top:0}.xv-bac-hep .xv-dk-bar{grid-column:1 / -1;min-height:48px}}.xv-dk{display:flex;align-items:center;justify-content:flex-start;gap:4px;flex-wrap:nowrap}.xv-nut{display:inline-flex;align-items:center;justify-content:center;min-width:44px;min-height:40px;padding:0 10px;background:var(--panel);border:1px solid var(--line);color:var(--ink);font-weight:600;text-decoration:none;cursor:pointer}.xv-nut:hover:not(:disabled){background:var(--chip)}.xv-nut:disabled{opacity:.4;cursor:default}.xv-nut-nho{min-width:36px;min-height:32px;padding:0 8px;font-size:13px}@media (max-width: 1023px){.xv-nut-nho{min-width:40px;min-height:40px}}.xv-nut:focus-visible,.xv-btn-chinh:focus-visible,.xv-nuoc:focus-visible{outline:2px solid var(--accent-dark);outline-offset:1px}.xv-btn-chinh{display:inline-flex;align-items:center;min-height:40px;padding:0 14px;background:var(--accent);color:var(--oninv);border:1px solid var(--accent-dark);font-weight:700;text-decoration:none;cursor:pointer}.xv-btn-chinh:hover{background:var(--accent-dark)}.xv-trang-thai{margin:0;text-align:center;color:var(--muted);font-weight:600;min-height:1.4em}.sh-acct{position:relative;display:flex;align-items:center}.sh-acct-login,.sh-acct-btn{display:inline-flex;align-items:center;gap:8px;min-height:44px;padding:0 10px;font-size:13px;font-weight:700;color:var(--ink);text-decoration:none;white-space:nowrap}.sh-acct-login{box-shadow:inset 0 -2px 0 var(--accent)}.sh-acct-ico{flex:none;display:block;color:var(--muted)}.sh-acct-login:hover .sh-acct-ico{color:var(--ink)}.sh-acct-btn{justify-content:center;width:44px;padding:0}.sh-acct-login:hover,.sh-acct-btn:hover{background:var(--accent-soft)!important}.sh-acct-login:focus-visible,.sh-acct-btn:focus-visible,.sh-acct-out:focus-visible{outline:2px solid var(--accent-dark);outline-offset:-2px}.sh-acct .sh-acct-ava{display:inline-flex;align-items:center;justify-content:center;width:34px;height:34px;flex:none;overflow:hidden;border-radius:50%!important;background:var(--accent);color:var(--oninv, #fff);font-size:15px;font-weight:800;line-height:1}.sh-acct .sh-acct-ava img{display:block;width:100%;height:100%;object-fit:cover;border-radius:50%!important}.sh-acct-name{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}.sh-acct-menu{position:absolute;right:0;top:100%;min-width:200px;background:var(--panel);border:1px solid var(--rule);box-shadow:0 6px 18px #2a23182e;z-index:400}.sh-acct-who{padding:10px 12px;font-size:12px;color:var(--muted);border-bottom:1px solid var(--line);overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.sh-acct-link{display:flex;align-items:center;min-height:44px;padding:0 12px;font-size:13px;font-weight:700;color:var(--ink);text-decoration:none;border-bottom:1px solid var(--line)}.sh-acct-link:hover,.sh-acct-link[aria-current=page]{background:var(--accent-soft)}.sh-acct-link:focus-visible{outline:2px solid var(--accent-dark);outline-offset:-2px}.sh-acct-out{display:block;width:100%;min-height:44px;padding:0 12px;text-align:left;font-size:13px;font-weight:700;color:var(--err)!important;padding:0 12px!important}.sh-acct-out:hover{background:var(--accent-soft)!important}[data-xq-theme=site]{--sh-header-h: 48px}.sh-header,.sh-header *,.sh-header *:before,.sh-header *:after{box-sizing:border-box;border-radius:0}:where(.sh-header) button{font:inherit;color:inherit;background:none;border:0;padding:0;cursor:pointer}.sh-header{font-family:var(--font);font-size:13px;line-height:1.4;color:var(--ink);display:flex;align-items:center;gap:22px;padding:0 14px;height:var(--sh-header-h);flex:none;border-bottom:2px solid var(--rule);background:var(--app);background-image:var(--tx);position:relative;z-index:300}.sh-brand{display:flex;align-items:center;flex:none}.sh-brand img{display:block}.sh-head-title{display:flex;flex-direction:column;min-width:0;flex:1}.sh-head-name{font-size:14px;font-weight:800;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.sh-head-sub{font-size:10.5px;color:var(--muted);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.sh-nav{display:flex;gap:2px;align-self:stretch;min-width:0;overflow:hidden}.sh-nav-link{display:flex;align-items:center;padding:0 10px;font-size:13px;white-space:nowrap;text-decoration:none;color:var(--muted)}.sh-nav-on{font-weight:800;color:var(--ink);box-shadow:inset 0 -2px 0 var(--accent)}.sh-right{margin-left:auto;display:flex;align-items:center;gap:8px;flex:none}.sh-gopy{flex:none;display:inline-flex;align-items:center;gap:6px;height:32px;padding:0 12px;border:1px solid var(--line);background:var(--panel);color:var(--ink);font-size:12.5px;font-weight:700;white-space:nowrap;cursor:pointer}.sh-gopy:hover{background:var(--chip)}.sh-gopy svg{flex:none}.sh-gopy:focus-visible{outline:2px solid var(--accent-dark);outline-offset:-2px}.sh-burger{flex:none;display:inline-flex;align-items:center;justify-content:center;min-width:44px;min-height:44px;color:var(--ink);cursor:pointer}.sh-burger:hover{background:var(--accent-soft)}@media (max-width: 1099px){.sh-nav{display:none}}@media (max-width: 767px){[data-xq-theme=site]{--sh-header-h: 52px}.sh-header{padding:0 12px;gap:10px}.sh-brand img{width:28px;height:28px}.sh-gopy{min-height:44px;min-width:44px;padding:0 8px}.sh-right{gap:2px}}@media (max-width: 399px){.sh-gopy{min-width:44px;min-height:44px;padding:0;justify-content:center}.sh-gopy .sh-gopy-chu{display:none}}@media (max-width: 399px){.sh-header .sh-acct-login{gap:6px;padding:0 6px}}@media (max-width: 339px){.sh-header .sh-acct-login{min-width:44px;justify-content:center}.sh-header .sh-acct-login>span{position:absolute;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}}.lb-trang{flex:1;min-height:0;display:flex;flex-direction:column}.lb-trang>.lesson-view{flex:1}.lb-trang .lb-luoi-khung{flex:1;min-height:0;display:flex;flex-direction:column}.lb-trang .lesson-view{display:flex}.lb-trang .lesson-sidebar{width:240px;min-width:240px;padding:16px 8px;border-right:1px solid var(--line);overflow-y:auto;max-height:100vh;position:sticky;top:0;display:flex;flex-direction:column;background:var(--side)}.lb-trang .sidebar-toggle{display:inline-flex;align-items:center;justify-content:center;width:32px;height:32px;margin-bottom:8px;align-self:flex-end;border:1px solid var(--rule);background:var(--field);color:var(--muted);font-size:16px;line-height:1;cursor:pointer}.lb-trang .sidebar-toggle:hover{background:var(--accent-soft);color:var(--accent-dark)}.lb-trang .back-link{display:block;padding:8px 10px;margin-bottom:12px;font-size:13px;font-weight:600;color:var(--accent-dark);text-decoration:none}.lb-trang .back-link:hover{background:var(--accent-soft)}.lb-trang .sidebar-topic-title{font-size:12px;text-transform:uppercase;letter-spacing:.06em;color:var(--muted);padding:0 10px 8px;margin-bottom:4px}.lb-trang .sidebar-lesson{display:block;padding:8px 10px;font-size:14px;color:var(--ink);cursor:pointer;text-decoration:none;position:relative}.lb-trang .sidebar-lesson:hover{background:#0000000a}.lb-trang .sidebar-lesson.active{background:var(--accent-soft);color:var(--accent-dark);font-weight:600}.lb-trang .sidebar-lesson.completed:before{content:"✓";color:var(--run);font-weight:700}.lb-trang .sidebar-report{margin-top:auto;padding:10px;border-top:1px solid var(--line)}.lb-trang .sidebar-report .report-trigger{font-size:13px}.lb-trang .lesson-view.sidebar-collapsed .lesson-sidebar{width:44px;min-width:44px;padding:16px 6px;align-items:center}.lb-trang .lesson-view.sidebar-collapsed .lesson-sidebar>:not(.sidebar-toggle){display:none}.lb-trang .lesson-view.sidebar-collapsed .sidebar-toggle{align-self:center;margin-bottom:0}.lb-trang .lesson-view.sidebar-collapsed .lesson-content{max-width:1200px}.lb-trang .lesson-content{flex:1;min-width:0;max-width:1060px;margin:0 auto;padding:4px 20px 24px}.lb-trang .lesson-grid{display:grid;grid-template-columns:minmax(430px,470px) minmax(340px,1fr);gap:16px;align-items:start}.lb-trang .board-column,.lb-trang .lesson-panel{background:var(--panel);border:1px solid var(--line);padding:8px 16px 16px;min-width:0}.lb-trang .board-column{max-width:100%;overflow:hidden}.lb-trang .lb-ban{display:block}.lb-trang .board-frame{margin-bottom:12px;margin-left:auto;margin-right:auto}.lb-trang .lb-thong-bao{padding:24px 4px;max-width:560px}.lb-trang .lb-thong-bao p{margin:0 0 10px;color:var(--muted);font-size:14px}.lb-trang #status{padding:10px 14px;font-size:15px;background:var(--field);border:1px solid var(--line);color:var(--muted)}.lb-trang #status.error{color:var(--err);background:#9c2b1614;border-color:#9c2b164d}.lb-trang #status.success{color:var(--run);background:#1f8a4c1a;border-color:#1f8a4c4d}@keyframes lesson-status-pulse{0%{transform:translate(0)}20%{transform:translate(-5px)}40%{transform:translate(5px)}60%{transform:translate(-3px)}80%{transform:translate(3px)}to{transform:translate(0)}}.lb-trang #status.pulse{animation:lesson-status-pulse .32s ease-in-out}@media (prefers-reduced-motion: reduce){@keyframes lesson-status-pulse{0%{opacity:1}50%{opacity:.45}to{opacity:1}}}.lb-trang #ptNext a{color:var(--accent-dark);font-weight:600}.lb-trang .lesson-square-highlight{box-shadow:inset 0 0 0 4px #7a4516fa,0 0 0 2px #ecc485d9;background:#7a45161f;box-sizing:border-box}.lb-trang .lesson-legal-dot{border-radius:50%;background:#e68f0073}.lb-trang .practice-hint-sq{box-sizing:border-box;border:3px solid #e0a52b;background:#e0a52b2e}.lb-trang .practice-hint-sq.target{border-color:#5c8a3a;background:#5c8a3a2e}.lb-trang svg.cg-shapes{shape-rendering:geometricPrecision}.lb-trang svg.cg-shapes line{stroke-width:.1!important}.lb-trang .panel-actions{display:flex;justify-content:flex-end;align-items:center;gap:6px;margin:0 0 8px}.lb-trang .ghost{background:transparent;border:1px solid var(--rule);color:var(--ink);padding:8px 14px;font:inherit;font-weight:600;cursor:pointer;text-decoration:none}.lb-trang .ghost.nav-btn{padding:0;font-size:18px;border-radius:50%}.lb-trang .ghost:hover,.lb-trang .ghost:focus-visible{border-color:var(--accent-dark);box-shadow:0 0 0 3px #c8913a29;outline:none}.lb-trang .panel-actions .ghost{min-height:32px;padding:4px 9px;line-height:1}@media (pointer: coarse){.lb-trang .panel-actions .ghost{min-height:44px;min-width:44px}}.lb-trang .mode-toggle{font-size:13px;white-space:nowrap}.lb-trang #modeToggleBtn{display:inline-flex;flex-direction:column;align-items:flex-end;line-height:1.25}.lb-trang #modeToggleBtn .mt-main{font-size:13px}.lb-trang #modeToggleBtn .mt-sub{font-size:11px;opacity:.62;font-weight:400}.lb-trang #proNotationToggle{display:inline-flex;gap:3px;align-items:center;letter-spacing:.04em;font-size:12px}.lb-trang #proNotationToggle .nt-off{opacity:.42;font-weight:400}@media (max-width: 560px){.lb-trang .panel-actions{flex-wrap:wrap}.lb-trang .panel-actions .egkb-chip{margin:0 0 6px;flex-basis:100%}}.lb-trang .lesson-panel-title{font-size:16px;font-weight:600;line-height:1.35;margin:0 0 12px;padding-bottom:10px;border-bottom:1px solid var(--line)}.lb-trang .step-progress{display:flex;gap:6px;margin-bottom:14px;flex-wrap:wrap}.lb-trang .step-progress.is-bar{display:block;margin-bottom:8px}.lb-trang .step-bar{height:5px;background:var(--accent-soft);overflow:hidden}.lb-trang .step-bar-fill{display:block;height:100%;background:var(--accent);transition:width .25s}.lb-trang .step-dot{width:28px;height:28px;border:2px solid var(--line);background:var(--panel);display:inline-flex;align-items:center;justify-content:center;font-size:12px;font-weight:600;color:var(--muted)}.lb-trang .step-dot.active{border-color:var(--accent);color:var(--accent-dark);background:var(--accent-soft)}.lb-trang .step-dot.done{border-color:var(--run);color:#fff;background:var(--run)}.lb-trang .lesson-goal{display:flex;align-items:center;gap:8px;padding:10px 14px;margin:0 0 12px;border:1px solid var(--line)}.lb-trang .lesson-goal-title{font-size:14px;font-weight:600}.lb-trang .lesson-goal-sub{font-size:12px}.lb-trang .lesson-goal-win{background:#9c2b1614}.lb-trang .lesson-goal-win .lesson-goal-title{color:#791f1f}.lb-trang .lesson-goal-win .lesson-goal-sub{color:#993c1d}.lb-trang .lesson-goal-draw{background:#dce9f5}.lb-trang .lesson-goal-draw .lesson-goal-title{color:#0c447c}.lb-trang .lesson-goal-draw .lesson-goal-sub{color:#185fa5}.lb-trang .lesson-preface{margin:2px 0 12px;font-size:13px;line-height:1.5;color:var(--ink)}.lb-trang .lesson-preface>summary{color:var(--muted)}.lb-trang .lesson-preface[open]{padding:8px 10px;border:1px solid var(--line);background:var(--accent-soft)}.lb-trang .lesson-preface[open]>summary{color:inherit;margin-bottom:4px}.lb-trang .lesson-preface-body{margin-top:6px;max-height:45vh;overflow:auto}.lb-trang #practiceObjective{margin:0 0 10px;padding:9px 12px;background:#e0a52b1f;border:1px solid rgba(224,165,43,.4);font-size:14px;line-height:1.4}.lb-trang #practiceObjective b{font-weight:600}.lb-trang .instruction-card{padding:16px;background:var(--field);border:1px solid var(--line);margin-bottom:14px;font-size:15px;line-height:1.6}.lb-trang .instruction-card h3{margin:0 0 4px;font-size:11px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:var(--muted)}.lb-trang .instruction-text{margin:0;color:var(--ink)}.lb-trang #practiceHintBtn{margin-top:8px}.lb-trang .btn{display:inline-flex;align-items:center;padding:10px 20px;border:1px solid var(--rule);background:var(--panel);color:var(--ink);font:inherit;font-weight:600;cursor:pointer}.lb-trang .btn:hover{border-color:var(--accent-dark)}.lb-trang .btn.primary{background:var(--accent);color:var(--oninv);border-color:var(--accent-dark)}.lb-trang .btn.primary:hover{background:var(--accent-dark)}.lb-trang .explanation-card{padding:16px;background:#1f8a4c1a;border:1px solid rgba(31,138,76,.3);margin-bottom:14px;font-size:15px;line-height:1.6}.lb-trang .explanation-card h3{margin:0 0 6px;font-size:14px;color:var(--run)}.lb-trang .explanation-text{margin:0;color:var(--ink)}.lb-trang .explanation-card .continue-btn{margin-top:12px;width:100%;justify-content:center}.lb-trang .lb-tu-dong-tiep{display:inline-block;margin:8px 0 0 2px;font-size:12px;color:var(--muted);cursor:pointer;-webkit-user-select:none;user-select:none}.lb-trang .lb-tu-dong-tiep input{margin-right:4px;vertical-align:middle}.lb-trang .lesson-complete{text-align:center;padding:16px;background:#1f8a4c1a;border:1px solid rgba(31,138,76,.3);display:flex;flex-direction:column;align-items:center;gap:10px}.lb-trang .lesson-complete h2{color:var(--run);margin:0}.lb-trang .lesson-complete p{color:var(--muted);margin:0}.lb-trang .xv-chu-s{margin:2px 0}.lb-trang .xv-chu-s:first-child{margin-top:0}.lb-trang .xv-chu-v{margin:3px 0 3px 12px;padding-left:8px;border-left:2px solid var(--line);opacity:.85;overflow-wrap:break-word}.lb-trang .xv-chu-v2{margin-left:12px}.lb-trang .egkb-chip{display:inline-flex;align-items:center;gap:6px;margin:0 auto 0 0;padding:3px 10px;border:1px solid var(--rule);background:var(--accent-soft);font-size:13px;font-weight:600;color:var(--accent-dark);line-height:1.4}.lb-trang .egkb-chip .egkb-chip-dot{opacity:.6;font-weight:400}.lb-trang .egkb-block{margin-top:12px;padding:12px 14px;border:1px solid var(--rule);background:var(--field);text-align:left;width:100%}.lb-trang .egkb-block .egkb-h{font-size:11px;letter-spacing:.06em;text-transform:uppercase;color:var(--muted);margin:0 0 2px;font-weight:700}.lb-trang .egkb-block .egkb-v{margin:0 0 10px;font-size:15px;font-weight:600;color:var(--ink)}.lb-trang .egkb-block .egkb-v:last-of-type{margin-bottom:0}.lb-trang .egkb-block .egkb-result{font-size:18px}.lb-trang .egkb-result-win{color:#1f7a37!important}.lb-trang .egkb-result-draw{color:#8a6d1f!important}.lb-trang .egkb-result-loss{color:#a33!important}.lb-trang .egkb-cond{white-space:pre-wrap;font-weight:500}.lb-trang .egkb-actions{margin-top:12px;display:flex;flex-wrap:wrap;gap:8px}.lb-trang .egkb-family-list{margin-top:10px;list-style:none;padding:0}.lb-trang .egkb-family-list li{margin:0}.lb-trang .egkb-family-list a{display:flex;justify-content:space-between;gap:10px;padding:7px 10px;border:1px solid var(--line);margin-top:6px;text-decoration:none;color:var(--ink);background:var(--panel)}.lb-trang .egkb-family-list a.egkb-current{border-color:var(--accent-dark);background:var(--accent-soft)}.lb-trang .egkb-family-list .egkb-li-res{font-size:12px;font-weight:700;opacity:.75}.lb-trang .egkb-family-empty,.lb-trang .egkb-family-err{margin-top:8px;color:#8a6d1f;font-size:13px}.lb-trang .board-nav{display:flex;justify-content:center;gap:6px;margin-top:8px}.lb-trang .pro-view .status{margin-top:6px;text-align:center;font-size:15px;color:var(--muted);min-height:22px}.lb-trang .pro-movelist{max-height:72vh;overflow:auto;padding-right:4px}.lb-trang .pro-move{display:inline-block;font:inherit;font-size:14px;padding:3px 8px;margin:2px 4px 2px 0;border:1px solid transparent;background:var(--chip);color:var(--ink);cursor:pointer}.lb-trang .pro-move.black{background:var(--phead)}.lb-trang .pro-move:hover{border-color:var(--rule)}.lb-trang .pro-move.current{background:var(--accent);color:var(--oninv);border-color:var(--accent-dark)}.lb-trang .pro-comment{font-size:13px;color:var(--muted);margin:2px 0 9px;line-height:1.5}.lb-trang .pro-preface{margin:0 0 10px;padding:8px 10px;border:1px solid var(--line);background:var(--accent-soft);font-size:13px;line-height:1.5;color:var(--ink)}.lb-trang .pro-preface summary{cursor:pointer;font-weight:600}.lb-trang .pro-preface-body{margin-top:6px;white-space:pre-wrap}.lb-trang .pro-movelist.hide-cmt .pro-comment{display:none}.lb-trang .pro-empty{color:var(--muted);font-size:13px}.lb-hop-nen{position:fixed;top:0;right:0;bottom:0;left:0;background:#1a15107a;display:grid;place-items:center;padding:20px;z-index:40}.lb-hop{width:min(100%,440px);background:var(--panel);border:1px solid var(--rule);box-shadow:0 8px 28px #2a231840;padding:22px;display:grid;gap:18px}.lb-hop-dau{display:flex;justify-content:space-between;align-items:center;gap:16px}.lb-hop-dau h3{margin:0;font-size:17px}.lb-hop-form{display:grid;gap:14px}.lb-hop-form label{display:grid;gap:8px;font-size:14px;color:var(--muted)}.lb-hop-form input{width:100%;border:1px solid var(--rule);padding:12px 14px;font:inherit;color:var(--ink);background:var(--field)}.lb-hop-hanh-dong{display:flex;justify-content:flex-end}.lb-nut-chinh{font:inherit;font-weight:600;padding:9px 18px;border:1px solid var(--accent-dark);background:var(--accent);color:var(--oninv);cursor:pointer}.lb-nut-chinh:hover{background:var(--accent-dark)}.lb-hop-tt{font-size:13px;line-height:1.5;color:var(--run);margin:0;min-height:1.5em}.lb-hop-tt.is-loi{color:var(--err)}@media (max-width: 1100px){.lb-trang .lesson-view:not(.sidebar-collapsed) .lesson-grid{grid-template-columns:minmax(0,1fr)}.lb-trang .lesson-view:not(.sidebar-collapsed) .board-column{max-width:520px;width:100%;justify-self:center}}@media (max-width: 880px){.lb-trang .lesson-view.sidebar-collapsed .lesson-grid{grid-template-columns:minmax(0,1fr)}.lb-trang .lesson-view.sidebar-collapsed .board-column{max-width:520px;width:100%;justify-self:center}}@media (max-width: 768px){.lb-trang .lesson-grid{grid-template-columns:1fr}.lb-trang .board-column{justify-self:stretch;padding:6px;border:none}.lb-trang .lesson-view{flex-direction:column}.lb-trang .lesson-content{order:1;padding:2px 8px 20px;max-width:100%;overflow:hidden}.lb-trang .lesson-content .board-frame,.lb-trang .lesson-content .board-row,.lb-trang .lesson-content .board,.lb-trang .lesson-content cg-container{max-width:100%}.lb-trang .lesson-preface-body{max-height:50vh;overflow:auto}.lb-trang .lesson-sidebar{order:2;width:100%;min-width:100%;max-height:none;position:static;border-right:none;border-top:1px solid var(--line);padding:8px}.lb-trang .sidebar-topic-title{font-size:13px;padding:8px 10px 4px}.lb-trang .sidebar-lessons{display:flex;gap:4px;flex-wrap:wrap}.lb-trang .sidebar-lesson{font-size:13px;padding:6px 10px;border:1px solid var(--line)}.lb-trang .sidebar-report{margin-top:8px;border-top:none;padding:4px 10px}.lb-trang .back-link{margin-bottom:4px}.lb-trang .lesson-view.sidebar-collapsed .lesson-sidebar{width:100%;min-width:100%;padding:8px}.lb-trang .lesson-view.sidebar-collapsed .sidebar-toggle{align-self:flex-start}}.lb-trang .xv-cot-trai .lesson-sidebar,.lb-trang .xv-bang .lesson-sidebar{width:auto;min-width:0;position:static;max-height:none;border-right:0;background:transparent}.lb-trang .xv-cot-trai .lesson-sidebar{flex:1;min-height:0;padding:8px}.lb-trang .xv-bang .lesson-sidebar{flex:none;width:100%;min-width:0;border:1px solid var(--line);background:var(--field);padding:8px}.lb-trang .xv-cot-phai .lesson-panel,.lb-trang .xv-bang .lesson-panel{background:transparent;border:0;padding:0}.lb-trang .xv-o-ban .board-frame{margin:0}.lb-trang .xv-dk .board-nav{margin-top:0;flex-wrap:nowrap}.lb-trang .xv-dk .nav-btn{width:40px;height:40px;flex:none}.lb-trang .xv-dk-bar #status,.lb-trang .xv-dk-bar .status{flex:1 1 140px;min-width:0;padding:6px 10px;font-size:14px;line-height:1.35}.lb-trang .xv-dk-bar .pro-view .status,.lb-trang .xv-dk-bar #proStatus{margin:0;min-height:0;text-align:left;font-size:13px}.lb-trang .xv-trang-thai-hang #status{padding:6px 10px;font-size:14px;text-align:center}.lb-trang .xv-trang-thai-hang .status{margin:0;min-height:0;text-align:center;font-size:13px}.lb-trang .xv-bang .pro-movelist,.lb-trang .xv-cot-phai .pro-movelist{max-height:none}.lb-trang .xv-cot-phai .lesson-preface-body{max-height:30vh}.lb-trang.gap-ben .xv-cot-trai .lesson-sidebar{padding:8px 6px;align-items:center}.lb-trang.gap-ben .lesson-sidebar>:not(.sidebar-toggle){display:none}.lb-trang.gap-ben .lesson-sidebar .sidebar-toggle{align-self:center;margin-bottom:0}.lb-trang.gap-ben .xv-bang .lesson-sidebar{padding:8px;align-items:flex-start}.lb-trang.gap-ben .xv-bang .lesson-sidebar .sidebar-toggle{align-self:flex-start}.tp-app{min-height:100vh;background:var(--app)}.tp-nut{font:inherit;font-size:13px;padding:6px 12px;border:1px solid var(--rule);background:var(--field);color:var(--ink);cursor:pointer}.tp-nut:hover{border-color:var(--accent-dark)}.tp-trong{color:var(--muted);font-size:13px;padding:14px 2px;margin:0}.tp-trong p{margin:0 0 8px}.tp-trong b{color:var(--ink)}.tp-het-phien{padding:10px 16px;background:var(--accent-soft);border-bottom:1px solid var(--rule);font-size:13px}.tp-lien-ket{font:inherit;font-size:13px;padding:0;border:0;background:none;color:var(--accent-dark);cursor:pointer;text-decoration:none}.tp-lien-ket:hover{text-decoration:underline}.tp-duyet{max-width:900px;margin:0 auto;padding:28px 16px 48px}.tp-dau{display:flex;align-items:flex-start;justify-content:space-between;gap:10px}.tp-dau-chinh{min-width:0}.tp-duyet h1{margin:0 0 2px;font-size:28px;line-height:1.2}.tp-crumb{font-size:13px;color:var(--muted);margin:2px 0 6px;min-height:18px}.tp-crumb a{color:var(--accent-dark);cursor:pointer;text-decoration:none}.tp-crumb a:hover{text-decoration:underline}.tp-thuat-ngu{flex:none;display:inline-flex;align-items:center;gap:5px;margin-top:2px;font-size:13px;line-height:1;text-decoration:none;color:var(--accent-dark);border:1px solid var(--rule);background:var(--field);padding:6px 11px}.tp-thuat-ngu:hover{border-color:var(--accent-dark);box-shadow:0 2px 8px #2a23181f}.tp-thuat-ngu .ico{font-size:15px;line-height:1}@media (max-width: 520px){.tp-thuat-ngu .lbl{display:none}}.tp-hang-tren{display:flex;flex-wrap:wrap;gap:16px;align-items:flex-start;margin:0 0 18px}.tp-hang-tren>.tp-hom-nay,.tp-hang-tren>.tp-on-lai{flex:1 1 340px;min-width:0}@media (max-width: 768px){.tp-hang-tren>.tp-hom-nay,.tp-hang-tren>.tp-on-lai{flex:1 1 100%}}.tp-hom-nay{padding:14px 16px;border:1px solid var(--rule);background:var(--panel)}.tp-hom-nay .pt-title{font-size:1.15rem;font-weight:700;margin:0 0 4px}.tp-hom-nay .pt-sub{font-size:.85rem;color:var(--muted);margin:0 0 12px}.tp-hom-nay .pt-dots{display:flex;gap:6px;margin:0 0 12px}.tp-hom-nay .pt-dot{width:22px;height:6px;background:var(--line)}.tp-hom-nay .pt-dot.done{background:var(--run)}.tp-hom-nay .pt-cta{display:inline-block;padding:9px 18px;font-weight:600;text-decoration:none;background:var(--accent);color:var(--oninv)}.tp-hom-nay .pt-cta:hover{background:var(--accent-dark)}.tp-hom-nay .pt-done{font-size:.9rem;color:var(--muted)}.tp-on-lai .mr-head{display:flex;align-items:baseline;gap:10px;margin:0 0 10px}.tp-on-lai .mr-title{font-size:1.05rem;font-weight:600;margin:0}.tp-on-lai .mr-sub{font-size:.85rem;color:var(--muted)}.tp-on-lai .mr-list{display:flex;flex-wrap:wrap;gap:10px}.tp-on-lai .mr-card{display:block;padding:10px 12px;border:1px solid var(--line);background:var(--panel);text-decoration:none;color:inherit;min-width:180px;max-width:280px}.tp-on-lai .mr-card:hover{border-color:var(--accent-dark)}.tp-on-lai .mr-name{font-weight:600;margin:0 0 4px}.tp-on-lai .mr-meta{font-size:.8rem;color:var(--muted)}.tp-tabs{display:flex;flex-wrap:wrap;gap:6px;margin:10px 0 2px}.tp-tab{font:inherit;font-size:13px;padding:6px 12px;border:1px solid var(--rule);background:var(--field);cursor:pointer;color:var(--ink);display:inline-flex;align-items:center}.tp-tab:hover{border-color:var(--accent-dark)}.tp-tab.on{background:var(--accent);color:var(--oninv);border-color:var(--accent-dark)}.tp-tab-n{opacity:.55;font-size:11px;margin-left:4px}.tp-tab.on .tp-tab-n{opacity:.85}.tp-tab .tp-tico{width:15px;height:15px;margin-right:5px;flex:none}.tp-thanh{margin:10px 0 4px}.tp-hang{display:flex;flex-wrap:wrap;gap:8px 10px;align-items:center}.tp-hang+.tp-hang{margin-top:7px;padding-top:7px;border-top:1px solid var(--line)}.tp-nhan{font-size:12px;color:var(--muted)}.tp-thanh input{font:inherit;font-size:13px;padding:5px 9px;min-width:200px;border:1px solid var(--rule);background:var(--field);color:var(--ink)}.tp-chip{font:inherit;font-size:12px;padding:4px 11px;border:1px solid var(--rule);background:var(--field);color:var(--ink);cursor:pointer}.tp-chip:hover{border-color:var(--accent-dark)}.tp-chip.on{background:var(--accent);color:var(--oninv);border-color:var(--accent-dark)}.tp-noi-dung{margin-top:4px}.tp-luoi{display:grid;grid-template-columns:repeat(auto-fill,minmax(230px,1fr));gap:10px;margin-top:8px}.tp-nhom{display:flex;align-items:center;font-weight:600;margin:14px 2px 6px;opacity:.85}.tp-luoi>.tp-nhom{grid-column:1 / -1;width:100%;flex-basis:100%}.tp-nhom .tp-ico{width:20px;height:20px;object-fit:contain;margin-right:7px;flex:none;filter:drop-shadow(0 1px 1px rgba(0,0,0,.2))}.tp-nhom .tp-gico{width:18px;height:18px;margin-right:7px;flex:none;color:var(--accent-dark)}.tp-the,.tp-the-sach{display:block;padding:12px 14px;border:1px solid var(--line);background:var(--panel);color:var(--ink);text-decoration:none;cursor:pointer}.tp-the:hover,.tp-the:focus-visible,.tp-the-sach:hover,.tp-the-sach:focus-visible{border-color:var(--accent-dark);box-shadow:0 2px 8px #2a23181f;outline:none}.tp-the .t,.tp-the-sach .t{font-size:13px;font-weight:600;margin-bottom:4px;line-height:1.35}.tp-the .m,.tp-the-sach .m{font-size:12px;color:var(--muted)}.tp-the .sub{font-size:11px;color:var(--muted);margin-bottom:5px}.tp-huy-hieu{display:inline-block;font-size:11px;padding:1px 7px;background:var(--chip);color:var(--accent-dark);margin-left:6px}.tp-sach{margin-top:8px}.tp-sach-d{font-size:12px;font-weight:600;color:var(--accent-dark);letter-spacing:.02em}.tp-the-sach{border-color:var(--rule);border-left:3px solid var(--accent-dark);background:var(--panel)}.tp-xem-them{display:block;width:100%;margin:12px 0 4px;padding:10px 14px;border:1px dashed var(--rule);background:var(--panel);text-align:center;font:inherit;font-size:13px;color:var(--accent-dark);cursor:pointer}.tp-xem-them:hover{border-style:solid;border-color:var(--accent-dark)}.tp-giu-cho p{padding:6px 2px}@media (pointer: coarse){.tp-tab,.tp-chip,.tp-thuat-ngu,.tp-nut,.tp-thanh input{min-height:44px}}[data-feedback-box]{--fb-header-h: 48px}@media (max-width: 767px){[data-feedback-box]{--fb-header-h: 52px}}[data-feedback-box],[data-feedback-box] *{box-sizing:border-box;border-radius:0}[data-feedback-box] button{font:inherit;color:inherit;background:none;border:0;padding:0;cursor:pointer}[data-feedback-box] button:disabled{opacity:.4;cursor:not-allowed}[data-feedback-box] input,[data-feedback-box] select,[data-feedback-box] textarea{font:inherit;color:inherit}:is(#phan-tich-feedback,[data-feedback-box]) .feedback-modal-backdrop{position:fixed;inset:var(--pt-header-h, var(--fb-header-h)) 0 0 0;z-index:200;display:flex;align-items:center;justify-content:center;padding:16px;background:#2a231866}:is(#phan-tich-feedback,[data-feedback-box]) .feedback-modal-backdrop[hidden]{display:none!important}:is(#phan-tich-feedback,[data-feedback-box]) .feedback-modal{width:min(520px,100%);max-height:calc(100vh - var(--pt-header-h, var(--fb-header-h)) - 32px);overflow:auto;background:var(--panel);border:2px solid var(--rule);color:var(--ink);font-family:var(--font);font-size:13px}:is(#phan-tich-feedback,[data-feedback-box]) .feedback-modal-header{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:10px 14px;background:var(--phead);border-bottom:2px solid var(--rule)}:is(#phan-tich-feedback,[data-feedback-box]) .feedback-modal-header h3{margin:0;font-size:13px;font-weight:800;letter-spacing:.06em;text-transform:uppercase}:is(#phan-tich-feedback,[data-feedback-box]) .feedback-form{display:flex;flex-direction:column;gap:10px;padding:14px}:is(#phan-tich-feedback,[data-feedback-box]) [hidden]{display:none!important}:is(#phan-tich-feedback,[data-feedback-box]) .feedback-form label{display:flex;flex-direction:column;gap:5px;font-size:11px;font-weight:800;letter-spacing:.08em;text-transform:uppercase;color:var(--muted)}:is(#phan-tich-feedback,[data-feedback-box]) .feedback-form textarea,:is(#phan-tich-feedback,[data-feedback-box]) .feedback-form input,:is(#phan-tich-feedback,[data-feedback-box]) .feedback-form select{width:100%;padding:8px 9px;background:var(--field);border:1px solid var(--rule);font-size:13px;font-weight:400;letter-spacing:normal;text-transform:none;color:var(--ink)}:is(#phan-tich-feedback,[data-feedback-box]) .feedback-form-actions{display:flex;justify-content:flex-end;gap:8px}:is(#phan-tich-feedback,[data-feedback-box]) .feedback-form-actions button{padding:7px 16px;font-size:12px;font-weight:800;border:2px solid var(--rule)}:is(#phan-tich-feedback,[data-feedback-box]) .feedback-form-actions button[type=submit]{background:var(--accent);color:var(--oninv);border-color:var(--accent)}:is(#phan-tich-feedback,[data-feedback-box]) .feedback-modal-status{margin:0;font-size:12px;color:var(--muted)}@media (max-width: 767px){:is(#phan-tich-feedback,[data-feedback-box]) .feedback-form-actions button,:is(#phan-tich-feedback,[data-feedback-box]) .feedback-modal-header button{min-height:44px;min-width:44px}}