@font-face{font-family:Vazirmatn;src:local("Vazirmatn"),local("Tahoma");font-display:swap}:root{color-scheme:dark;font-family:Vazirmatn,Tahoma,Arial,sans-serif;font-synthesis:none}*{box-sizing:border-box}html,body{min-height:100%;margin:0;background:#080a0c}button,input{font:inherit}button{-webkit-tap-highlight-color:transparent}button:focus-visible,input:focus-visible{outline:3px solid var(--focus);outline-offset:3px}.chess-app{--bg: #080a0c;--bg-raised: #0d1014;--bg-soft: #141920;--panel: rgba(13, 16, 20, .94);--panel-strong: rgba(8, 10, 12, .985);--line: rgba(198, 161, 91, .46);--line-soft: rgba(198, 161, 91, .18);--accent: #c6a15b;--accent-bright: #e2c27c;--accent-soft: rgba(198, 161, 91, .16);--accent-ink: #17130d;--secondary: #8f7142;--text: #f3ebdd;--text-soft: #d8ccb8;--muted: #9a9285;--success: #9ed36a;--danger: #d9746c;--focus: #e2c27c;--board-light: #d6c5a5;--board-light-alt: #e8dbc0;--board-dark: #4b3423;--board-dark-alt: #2e2118;--piece-white: #f4e5c9;--piece-white-edge: #8e6b38;--piece-black: #111419;--piece-black-edge: #89919a;--shadow: rgba(0, 0, 0, .38);--card-radius: 18px;--button-radius: 12px;--board-radius: 14px;--board-frame: #111419;--topbar-bg: rgba(8, 10, 12, .88);position:relative;isolation:isolate;min-height:100dvh;overflow-x:hidden;color:var(--text);background:radial-gradient(circle at 45% 18%,rgba(198,161,91,.09),transparent 32%),linear-gradient(145deg,#050607,var(--bg) 56%,#0c0e11)}.chess-app[data-theme=modern]{--bg: #07111f;--bg-raised: #0b1930;--bg-soft: #112645;--panel: rgba(16, 29, 53, .88);--panel-strong: rgba(8, 21, 43, .97);--line: rgba(94, 147, 202, .44);--line-soft: rgba(94, 147, 202, .2);--accent: #35e7ff;--accent-bright: #66eeff;--accent-soft: rgba(53, 231, 255, .18);--accent-ink: #07111f;--secondary: #8b5cf6;--text: #f4f7ff;--text-soft: #c4d1e5;--muted: #91a3bf;--success: #46e6a7;--danger: #ff647c;--focus: #35e7ff;--board-light: #b6d7e5;--board-light-alt: #d3edf5;--board-dark: #244c68;--board-dark-alt: #173953;--piece-white: #fff6df;--piece-white-edge: #9e9276;--piece-black: #111923;--piece-black-edge: #6f8499;--shadow: rgba(0, 0, 0, .3);--card-radius: 20px;--button-radius: 13px;--board-frame: #06101f;--topbar-bg: rgba(7, 17, 31, .8);background:linear-gradient(rgba(53,231,255,.023) 1px,transparent 1px),linear-gradient(90deg,rgba(53,231,255,.023) 1px,transparent 1px),radial-gradient(circle at 45% 28%,rgba(20,100,155,.26),transparent 38%),linear-gradient(145deg,#07111f,#08152b 58%,#050c18);background-size:32px 32px,32px 32px,auto,auto}.chess-app[data-theme=classic]{color-scheme:light;--bg: #f4ebdd;--bg-raised: #fbf7ef;--bg-soft: #ede0cc;--panel: rgba(251, 247, 239, .96);--panel-strong: #fbf7ef;--line: #d8c9b4;--line-soft: rgba(107, 66, 38, .14);--accent: #244a3a;--accent-bright: #356b55;--accent-soft: rgba(36, 74, 58, .13);--accent-ink: #fff9ef;--secondary: #b9904a;--text: #25231f;--text-soft: #534b43;--muted: #776b5e;--success: #23864e;--danger: #b84d45;--focus: #9a6e27;--board-light: #fbf7ef;--board-light-alt: #efe1c9;--board-dark: #244a3a;--board-dark-alt: #1d3e31;--piece-white: #f2ddbd;--piece-white-edge: #8c673c;--piece-black: #4e2f1c;--piece-black-edge: #2b1a11;--shadow: rgba(63, 42, 24, .13);--card-radius: 14px;--button-radius: 9px;--board-radius: 8px;--board-frame: #6b4226;--topbar-bg: rgba(244, 235, 221, .92);background:radial-gradient(circle at 20% 10%,rgba(185,144,74,.08),transparent 34%),repeating-linear-gradient(0deg,transparent 0 3px,rgba(107,66,38,.013) 4px),#f4ebdd}.ambient{position:fixed;z-index:-1;width:32rem;height:32rem;border-radius:50%;opacity:.18;filter:blur(110px);pointer-events:none}.ambient-one{top:-16rem;left:12%;background:var(--accent)}.ambient-two{right:-18rem;bottom:-14rem;background:var(--secondary)}.topbar{position:sticky;z-index:30;top:0;display:flex;min-height:74px;align-items:center;justify-content:space-between;padding:10px clamp(18px,3vw,42px);border-bottom:1px solid var(--line-soft);background:var(--topbar-bg);backdrop-filter:blur(18px) saturate(130%)}.brand{display:flex;align-items:center;gap:13px;direction:ltr}.brand-mark{display:grid;width:48px;height:48px;place-items:center;border:1px solid var(--line);border-radius:15px;color:var(--accent-bright);background:linear-gradient(145deg,var(--accent-soft),transparent),var(--bg-raised)}.brand-mark span{transform:translateY(-1px);font:34px/1 Georgia,serif}.brand-title,.brand-subtitle{margin:0}.brand-title{color:var(--text);font:600 clamp(16px,1.65vw,24px)/1 Georgia,serif;letter-spacing:.13em}.brand-title span{color:var(--accent-bright)}.brand-subtitle{margin-top:4px;direction:rtl;color:var(--muted);font-size:11px;font-weight:700}.topbar-actions,.quick-themes{display:flex;align-items:center}.topbar-actions{gap:8px}.quick-themes{gap:7px;margin-left:5px;padding:7px 9px;border:1px solid var(--line-soft);border-radius:999px;background:var(--bg-raised)}.theme-dot{display:grid;width:29px;height:29px;padding:0;place-items:center;border:1px solid transparent;border-radius:50%;background:transparent;cursor:pointer}.theme-dot span{width:14px;height:14px;border:2px solid rgba(255,255,255,.48);border-radius:50%;background:var(--swatch);box-shadow:0 0 0 2px color-mix(in srgb,var(--swatch),transparent 72%)}.theme-dot:hover,.theme-dot.active{border-color:var(--accent);background:var(--accent-soft)}.icon-button{display:inline-flex;min-width:44px;height:44px;align-items:center;justify-content:center;gap:8px;padding:0 12px;border:1px solid var(--line-soft);border-radius:11px;color:var(--text-soft);background:var(--bg-raised);cursor:pointer;transition:.15s ease}.icon-button:hover{transform:translateY(-1px);border-color:var(--line);color:var(--accent-bright);background:var(--bg-soft)}.icon-button.labeled{font-weight:800}.arena-grid{display:grid;grid-template-columns:minmax(0,1fr) minmax(330px,402px);gap:clamp(16px,2vw,28px);width:min(1480px,100%);margin:auto;padding:clamp(16px,2vw,28px) clamp(14px,2.4vw,36px) 32px;direction:ltr}.board-column,.control-rail{direction:rtl}.board-column{display:flex;min-width:0;flex-direction:column;align-items:center}.board-shell{width:min(100%,calc(100dvh - 132px),800px);padding:clamp(9px,1vw,13px);border:1px solid var(--line);border-radius:calc(var(--board-radius) + 6px);background:linear-gradient(145deg,rgba(255,255,255,.055),transparent 25%),var(--board-frame);box-shadow:0 22px 55px var(--shadow),inset 0 1px #ffffff14}[data-theme=royal] .board-shell{border:2px solid var(--line);box-shadow:0 24px 60px #00000075,0 0 0 4px #c6a15b0f,inset 0 0 0 1px #e2c27c2e}[data-theme=modern] .board-shell{box-shadow:0 24px 64px #00000057,0 0 30px #35e7ff14,inset 0 0 0 1px #35e7ff2e}[data-theme=classic] .board-shell{padding:clamp(12px,1.6vw,24px);border:0;background:linear-gradient(90deg,rgba(255,255,255,.08),transparent 30%),repeating-linear-gradient(90deg,#ffffff06 0 5px,#2d190d09 6px),#6b4226;box-shadow:0 18px 34px #271c1233,inset 0 0 0 2px #b9904acc}.board-clock{display:none;align-items:center;gap:8px;padding:4px 4px 10px;color:var(--muted);font-size:13px}.board-clock-bottom{padding:10px 4px 2px}.board-clock strong{margin-right:auto;color:var(--text);font:700 15px/1 Arial,sans-serif}.clock-dot{width:8px;height:8px;border-radius:50%;background:var(--muted)}.clock-dot.active{background:var(--accent);box-shadow:0 0 12px var(--accent)}.chessboard{display:grid;overflow:hidden;grid-template-columns:repeat(8,minmax(0,1fr));width:100%;aspect-ratio:1;border:1px solid rgba(0,0,0,.38);border-radius:var(--board-radius);direction:ltr;background:var(--board-dark)}.square{position:relative;display:grid;min-width:0;padding:0;place-items:center;overflow:hidden;aspect-ratio:1;border:0;border-radius:0;color:inherit;cursor:pointer;isolation:isolate}.square-light{background:radial-gradient(circle at 25% 22%,rgba(255,255,255,.13),transparent 36%),linear-gradient(135deg,var(--board-light-alt),var(--board-light))}.square-dark{background:repeating-linear-gradient(4deg,rgba(255,255,255,.018) 0 2px,transparent 3px 7px),linear-gradient(135deg,var(--board-dark),var(--board-dark-alt))}[data-theme=modern] .square-light{background:linear-gradient(135deg,rgba(255,255,255,.14),transparent),var(--board-light)}[data-theme=modern] .square-dark{background:linear-gradient(135deg,rgba(53,231,255,.05),transparent),var(--board-dark)}[data-theme=classic] .square-light{background:radial-gradient(circle at 70% 25%,rgba(107,66,38,.035),transparent 42%),var(--board-light)}[data-theme=classic] .square-dark{background:var(--board-dark)}.square:before{position:absolute;z-index:0;inset:0;content:"";pointer-events:none;transition:.12s ease}.square:hover:before{background:#ffffff14}.square.last-move:before{background:color-mix(in srgb,var(--accent),transparent 72%);box-shadow:inset 0 0 0 2px color-mix(in 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var(--piece-white-edge),1px 1px 0 var(--piece-white-edge),0 5px 6px rgba(0,0,0,.34)}.piece-black{color:var(--piece-black);text-shadow:-1px -1px 0 var(--piece-black-edge),1px -1px 0 var(--piece-black-edge),-1px 1px 0 var(--piece-black-edge),1px 1px 0 var(--piece-black-edge),0 5px 7px rgba(0,0,0,.42)}.move-marker{position:absolute;z-index:4;width:22%;aspect-ratio:1;border:2px solid color-mix(in srgb,var(--accent),white 10%);border-radius:50%;background:color-mix(in srgb,var(--accent),transparent 34%);box-shadow:0 0 12px color-mix(in srgb,var(--accent),transparent 45%)}.capture-marker{position:absolute;z-index:4;inset:5px;border:clamp(3px,.42vw,6px) solid color-mix(in srgb,var(--accent),transparent 15%);border-radius:50%}.hint-marker{position:absolute;z-index:5;top:8px;right:8px;width:10px;height:10px;border:2px solid var(--panel);border-radius:50%;background:var(--secondary);box-shadow:0 0 12px var(--secondary)}.coordinate{position:absolute;z-index:5;font:800 clamp(9px,1vw,13px)/1 Arial,sans-serif;pointer-events:none}.square-light .coordinate{color:color-mix(in srgb,var(--board-dark),transparent 18%)}.square-dark .coordinate{color:color-mix(in srgb,var(--board-light),transparent 15%)}.coordinate-file{right:5px;bottom:4px}.coordinate-rank{top:5px;left:5px}.control-rail{display:flex;min-width:0;max-height:calc(100dvh - 105px);flex-direction:column;gap:11px;overflow-y:auto;padding-left:4px;scrollbar-color:var(--line) transparent;scrollbar-width:thin}.panel{border:1px solid var(--line);border-radius:var(--card-radius);background:linear-gradient(145deg,rgba(255,255,255,.035),transparent 45%),var(--panel);box-shadow:0 14px 34px var(--shadow),inset 0 1px #ffffff0b;backdrop-filter:blur(16px) saturate(120%)}[data-theme=classic] .panel{box-shadow:0 8px 22px #3f2a1817;backdrop-filter:none}.opponent-card{position:relative;display:grid;grid-template-columns:68px 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