:root{--bg:#f4f7fb;--card:#fff;--ink:#17212b;--muted:#617083;--navy:#12355b;--blue:#1769aa;--red:#df2929;--line:#dce5ef;--light:rgb(235,236,208);--dark:rgb(115,149,82);--shadow:0 14px 38px rgba(18,53,91,.10)}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:linear-gradient(180deg,#f8fbff,#eef3f8);color:var(--ink);font-family:Inter,system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif}.topbar{height:68px;padding:0 clamp(12px,3vw,40px);display:flex;align-items:center;justify-content:space-between;background:rgba(255,255,255,.95);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:30}.brand{display:flex;align-items:center;gap:10px;text-decoration:none;color:inherit}.brand strong{display:block;font-size:20px;color:var(--navy)}.brand strong i{font-style:normal;color:#1478cf}.brand small{display:block;color:var(--muted);font-size:11px}.series-logo{width:48px;height:48px;position:relative;overflow:hidden;border-radius:12px;background:white}.series-logo img{width:100%;height:100%;object-fit:cover}.series-logo b{position:absolute;right:1px;bottom:3px;background:#e30909;color:#fff;font-size:8px;padding:2px 4px;border-radius:4px;box-shadow:0 0 0 1px #ff5757}.navlinks{display:flex;gap:18px}.navlinks a{font-size:13px;font-weight:750;color:#536579;text-decoration:none}main{max-width:1700px;margin:auto;padding:0 clamp(8px,2vw,28px) 48px}.hero{display:grid;grid-template-columns:1.5fr .7fr;gap:26px;align-items:center;padding:34px 8px 22px}.eyebrow{font-size:11px;letter-spacing:.12em;font-weight:900;color:var(--blue);text-transform:uppercase}.hero h1{font-size:clamp(31px,4.3vw,60px);line-height:1.02;color:var(--navy);margin:6px 0 12px;letter-spacing:-1.4px}.hero p{max-width:900px;color:var(--muted);font-size:clamp(14px,1.3vw,18px);line-height:1.6;margin:0}.hero-card{justify-self:end;min-width:320px;padding:22px 24px;background:linear-gradient(145deg,#153b65,#0c2745);color:white;border-radius:20px;box-shadow:var(--shadow)}.hero-card span,.hero-card small{display:block;opacity:.75}.hero-card strong{display:block;font-size:25px;padding:7px 0}.level-gate{margin:0 8px 18px;background:white;border:1px solid var(--line);border-radius:20px;padding:18px 20px;display:flex;align-items:center;justify-content:space-between;gap:18px;box-shadow:var(--shadow)}.level-gate h2{margin:3px 0 3px;color:var(--navy)}.level-gate p{margin:0;color:var(--muted);font-size:13px}.level-actions{display:flex;gap:10px;min-width:420px}.level-btn{flex:1;border:1px solid #d9e3ee;background:#fff;border-radius:14px;padding:10px 14px;display:grid;grid-template-columns:32px 1fr;grid-template-rows:auto auto;text-align:left;cursor:pointer}.level-btn>span{grid-row:1/3;font-size:24px}.level-btn strong{font-size:15px;color:var(--navy)}.level-btn small{color:var(--muted)}.level-btn.primary{background:var(--navy);color:white}.level-btn.primary strong,.level-btn.primary small{color:white}.soon{position:fixed;inset:0;background:rgba(0,0,0,.35);display:grid;place-items:center;z-index:50}.soon[hidden]{display:none}.soon>div{width:min(420px,90vw);background:white;border-radius:18px;padding:22px;box-shadow:0 30px 80px rgba(0,0,0,.25)}.soon b{font-size:21px;color:var(--navy)}.soon p{color:var(--muted);line-height:1.55}.soon button{border:0;background:var(--navy);color:white;border-radius:10px;padding:9px 18px;font-weight:800}.course-switch{display:flex;align-items:center;gap:8px;flex-wrap:wrap;padding:0 8px 12px}.course-switch>span{font-size:12px;font-weight:800;color:var(--muted);margin-right:4px}.course-btn{border:1px solid #d8e2ec;background:#fff;color:var(--navy);border-radius:999px;padding:8px 13px;font-weight:800;cursor:pointer}.course-btn.active{background:var(--navy);color:#fff}.learning-shell{display:grid;grid-template-columns:310px minmax(0,1fr);background:#fff;border:1px solid var(--line);border-radius:24px;overflow:hidden;box-shadow:var(--shadow);min-height:760px}.library-panel{background:#f8fafc;border-right:1px solid var(--line);padding:17px}.panel-title{display:flex;align-items:flex-start;justify-content:space-between;gap:8px}.panel-title h2{margin:3px 0 13px;font-size:23px;color:var(--navy)}.count-pill{background:#e8f4ff;color:#11548c;border-radius:999px;padding:5px 8px;font-size:10px;font-weight:900}.searchbox{display:flex;gap:8px;background:#fff;border:1px solid #dce5ef;border-radius:11px;padding:9px;margin-bottom:10px}.searchbox input{width:100%;border:0;outline:0}.opening-list{display:flex;flex-direction:column;gap:5px;max-height:820px;overflow:auto}.opening-item{border:0;background:transparent;text-align:left;border-radius:11px;padding:9px 10px;cursor:pointer;color:#33485e}.opening-item:hover{background:#edf4fb}.opening-item.active{background:#e1effb;box-shadow:inset 3px 0 0 var(--blue)}.opening-item strong{display:block;font-size:13px}.opening-item small{display:block;font-size:10px;color:#76879a;margin-top:2px}.viewer-panel{padding:16px;min-width:0}.viewer-head{display:flex;justify-content:space-between;gap:12px;align-items:flex-start;margin-bottom:12px}.viewer-head h2{font-size:clamp(22px,2vw,31px);margin:2px 0 3px;color:var(--navy)}.opening-moves{font-family:Georgia,serif;font-size:17px;color:#536274;margin:0}.head-actions{display:flex;gap:6px}.ghost{border:1px solid #d7e1eb;background:white;border-radius:10px;padding:8px 11px;font-weight:800;color:var(--navy);cursor:pointer}.viewer-grid{display:grid;grid-template-columns:minmax(520px,1fr) minmax(350px,470px);gap:16px;align-items:start}.board-column{display:flex;flex-direction:column;align-items:center;min-width:0}.board-wrap{width:min(80vh,100%);max-width:900px;aspect-ratio:1;border-radius:7px;overflow:hidden;box-shadow:0 8px 28px rgba(0,0,0,.18);border:1px solid rgba(0,0,0,.08)}.chess-board{width:100%;height:100%;display:grid;grid-template-columns:repeat(8,1fr);grid-template-rows:repeat(8,1fr)}.sq{position:relative;display:grid;place-items:center;user-select:none}.sq.light{background:var(--light)}.sq.dark{background:var(--dark)}.sq.last:after{content:"";position:absolute;inset:0;background:rgba(246,220,74,.35)}.sq img{width:92%;height:92%;object-fit:contain;position:relative;z-index:2}.coord{position:absolute;font-size:10px;font-weight:900;z-index:3}.coord.file{right:3px;bottom:1px}.coord.rank{left:3px;top:1px}.light .coord{color:#739552}.dark .coord{color:#ebeccf}.controls{display:flex;justify-content:center;gap:6px;width:100%;margin-top:10px}.controls button,.controls select{height:40px;border:1px solid #d5e0eb;background:#fff;border-radius:9px;min-width:43px;font-weight:850;color:#213c57}.controls .play{min-width:94px;background:var(--navy);color:white}.position-strip{display:flex;justify-content:space-between;width:min(80vh,100%);max-width:900px;margin-top:6px;color:#68798a;font-size:12px}.study-column{display:flex;flex-direction:column;gap:9px;min-width:0}.mode-tabs{display:grid;grid-template-columns:1fr 1fr;background:#edf2f7;border-radius:11px;padding:4px}.tab{border:0;background:transparent;padding:9px;border-radius:8px;font-weight:850;color:#627386;cursor:pointer}.tab.active{background:white;color:var(--navy);box-shadow:0 2px 8px rgba(0,0,0,.06)}.famous-select{width:100%;border:1px solid #d9e3ed;border-radius:10px;padding:9px;background:#fff;font-weight:750;color:#28435d}.famous-meta{font-size:11px;color:#718295}.teacher-card{border:1px solid #cfe0ef;background:linear-gradient(180deg,#f8fcff,#fff);border-radius:15px;padding:14px;box-shadow:0 5px 18px rgba(20,65,100,.06)}.teacher-title{display:flex;justify-content:space-between;align-items:flex-start}.teacher-title span{font-size:10px;font-weight:900;letter-spacing:.12em;color:var(--blue)}.teacher-title h3{margin:2px 0 7px;color:var(--navy);font-size:18px}.teacher-title b{font-size:25px}.teacher-card>p{margin:0;color:#344b60;line-height:1.55;font-size:13px}.think{margin-top:10px;background:#fff7e8;border:1px solid #f0dfbd;border-radius:10px;padding:9px}.think strong{font-size:11px;color:#865b10}.think p{margin:3px 0 0;font-size:12px;color:#66583e}.alternative{margin-top:10px;border-top:1px dashed #cfdae5;padding-top:9px}.alternative>div:first-child{display:flex;justify-content:space-between;gap:8px}.alternative strong{font-size:12px;color:var(--navy)}.alternative small{font-size:10px;color:#7a8999}.alt-list{display:flex;flex-wrap:wrap;gap:5px;margin-top:7px}.alt-btn,.return-main{border:1px solid #c8d9e8;background:#edf6ff;color:#174e7c;border-radius:8px;padding:6px 8px;font-size:11px;font-weight:800;cursor:pointer}.return-main{margin-top:7px;background:#fff}.alt-empty{font-size:11px;color:#85929f}.brief-card,.moves-card,.pgn-card{border:1px solid var(--line);border-radius:13px;background:#fff}.brief-card{padding:12px}.brief-card h3{margin:0 0 5px;color:var(--navy);font-size:14px}.brief-card>p{font-size:12px;line-height:1.45;color:#596b7d;margin:0 0 9px}.mini-grid{display:grid;grid-template-columns:1fr 1fr;gap:7px}.mini-grid div{background:#f6f8fb;border-radius:9px;padding:8px}.mini-grid span{font-size:9px;font-weight:900;color:#5d7286;text-transform:uppercase}.mini-grid p{font-size:11px;line-height:1.4;margin:3px 0 0;color:#465a6c}.moves-card{overflow:hidden}.card-head{display:flex;justify-content:space-between;padding:9px 11px;border-bottom:1px solid var(--line)}.card-head h3{margin:0;font-size:13px;color:var(--navy)}.card-head span{font-size:9px;color:#8897a6}.move-list{max-height:205px;overflow:auto;padding:8px;display:flex;flex-wrap:wrap;gap:3px}.move-no{font-size:11px;color:#8b98a5;padding:4px 2px 4px 5px}.move-btn{border:0;background:#f1f4f7;border-radius:6px;padding:4px 6px;font-family:Georgia,serif;font-weight:700;cursor:pointer}.move-btn.active{background:var(--navy);color:#fff}.pgn-card{overflow:hidden}.pgn-card summary{cursor:pointer;padding:9px 11px;font-size:12px;font-weight:800}.pgn-card pre{margin:0;border-top:1px solid var(--line);padding:10px;white-space:pre-wrap;word-break:break-word;background:#f8fafc;color:#405266;max-height:220px;overflow:auto;font:11px/1.5 Consolas,monospace}.info-section{display:grid;grid-template-columns:330px 1fr;gap:35px;padding:50px 12px 25px}.info-section h2{font-size:30px;color:var(--navy);margin:5px 0}.info-section p{font-size:15px;line-height:1.65;color:#596a7c;margin:0 0 10px}.how-section{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;padding:0 12px 28px}.how-card{background:white;border:1px solid var(--line);border-radius:14px;padding:16px}.how-card>strong{display:grid;place-items:center;width:28px;height:28px;border-radius:50%;background:#e8f4ff;color:var(--blue)}.how-card h3{font-size:15px;color:var(--navy);margin:9px 0 4px}.how-card p{font-size:12px;color:#667688;line-height:1.5;margin:0}footer{padding:18px clamp(18px,3vw,42px) 32px;border-top:1px solid var(--line);display:flex;justify-content:space-between;color:#788899;font-size:12px}footer a{color:var(--blue)}.error{padding:12px;color:#9a302c}
@media(max-width:1200px){.learning-shell{grid-template-columns:250px 1fr}.viewer-grid{grid-template-columns:1fr}.board-wrap,.position-strip{width:min(72vh,100%)}.study-column{display:grid;grid-template-columns:1fr 1fr}.mode-tabs,.famous-select,.famous-meta,.teacher-card,.pgn-card{grid-column:1/-1}.opening-list{max-height:1200px}}
@media(max-width:760px){.topbar{height:60px}.navlinks{display:none}.series-logo{width:42px;height:42px}main{padding:0 7px 28px}.hero{grid-template-columns:1fr;padding:22px 7px 15px}.hero-card{display:none}.level-gate{display:block;margin:0 7px 12px;padding:14px}.level-actions{min-width:0;margin-top:12px}.course-switch{padding:0 7px 9px}.course-btn{font-size:11px;padding:7px 9px}.learning-shell{display:block;border-radius:15px}.library-panel{border-right:0;border-bottom:1px solid var(--line);padding:11px}.opening-list{display:grid;grid-auto-flow:column;grid-auto-columns:minmax(185px,72vw);overflow-x:auto;overflow-y:hidden;max-height:none}.viewer-panel{padding:8px}.viewer-head{align-items:center}.viewer-head h2{font-size:20px}.opening-moves{font-size:13px}.head-actions .ghost{font-size:11px;padding:7px}.viewer-grid{display:block}.board-wrap,.position-strip{width:min(96vw,72vh);max-width:100%}.study-column{display:flex;margin-top:10px}.controls{gap:3px}.controls button,.controls select{height:37px;min-width:37px;font-size:11px}.controls .play{min-width:75px}.mini-grid{grid-template-columns:1fr}.info-section{grid-template-columns:1fr;padding:36px 8px 20px;gap:6px}.how-section{grid-template-columns:1fr 1fr;padding:0 8px 20px}footer{flex-direction:column;gap:5px}.coord{font-size:8px}}
@media(max-width:480px){.level-actions{display:grid}.how-section{grid-template-columns:1fr}.brand strong{font-size:17px}.hero h1{font-size:31px}}

/* Advanced ChessPicker practice + review */
.practice-btn{border:0;background:#1f6f4a;color:#fff;border-radius:10px;padding:8px 12px;font-weight:900;cursor:pointer;white-space:nowrap}.play-panel{border:1px solid #cbdde8;background:linear-gradient(180deg,#f8fcff,#fff);border-radius:16px;padding:14px;margin-bottom:14px;box-shadow:0 8px 24px rgba(18,53,91,.08)}.play-head{display:flex;justify-content:space-between;gap:12px;align-items:flex-start}.play-head h2{margin:2px 0 3px;color:var(--navy);font-size:23px}.play-head p{margin:0;color:#617386;font-size:12px}.play-settings{display:grid;grid-template-columns:160px 190px 1fr auto;gap:8px;align-items:end;margin-top:11px}.play-settings label{font-size:10px;font-weight:900;color:#66788a;text-transform:uppercase}.play-settings select{display:block;width:100%;margin-top:4px;border:1px solid #cfdae5;border-radius:9px;padding:9px;background:#fff;color:#23405b;font-weight:750}.play-settings .checkline{display:flex;gap:7px;align-items:center;text-transform:none;font-size:11px;background:#f3f7fa;border-radius:9px;padding:9px}.primary-action{border:0;background:var(--navy);color:#fff;border-radius:9px;padding:10px 15px;font-weight:900;cursor:pointer}.game-tools{display:flex;flex-wrap:wrap;gap:6px;margin-top:9px}.game-tools button{border:1px solid #d3dee8;background:#fff;color:#27435e;border-radius:8px;padding:7px 9px;font-size:11px;font-weight:800;cursor:pointer}.game-tools button:disabled{opacity:.45;cursor:not-allowed}.learning-shell.playing .library-panel{opacity:.72}.sq.selected:before{content:"";position:absolute;inset:5%;border:4px solid rgba(34,104,167,.75);border-radius:8px;z-index:4}.sq.target:before{content:"";position:absolute;width:24%;height:24%;border-radius:50%;background:rgba(26,105,68,.55);z-index:4}.review-summary{margin-top:10px}.review-summary>div:first-child{display:flex;justify-content:space-between;background:#eef6ff;border-radius:10px;padding:9px;color:#173d61}.badges{display:flex;flex-wrap:wrap;gap:5px;margin-top:7px}.grade{display:inline-block;border-radius:999px;padding:3px 7px;font-size:10px;font-weight:900;background:#e8eef4;color:#31485e}.grade.Best,.grade.Excellent{background:#dff5e7;color:#17613c}.grade.Good{background:#e8f2ff;color:#24598a}.grade.Inaccuracy{background:#fff2cf;color:#7b5b08}.grade.Mistake,.grade.Missed-Chance{background:#ffe0bb;color:#8b4d00}.grade.Blunder{background:#ffd8d5;color:#932c25}.review-list{margin-top:8px;max-height:280px;overflow:auto}.review-row{border-top:1px solid #e4ebf2;padding:8px 2px}.review-row b{color:#243f5a}.review-row>.grade{margin-left:6px}.review-row p{margin:4px 0 0;color:#5f7081;font-size:11px;line-height:1.45}
@media(max-width:1000px){.play-settings{grid-template-columns:1fr 1fr}.play-settings .checkline{grid-column:1/-1}.primary-action{grid-column:1/-1}.head-actions{flex-wrap:wrap;justify-content:flex-end}.practice-btn{order:-1}}
@media(max-width:600px){.play-settings{grid-template-columns:1fr}.play-settings .checkline,.primary-action{grid-column:auto}.play-head{display:block}.play-head .ghost{margin-top:8px}.practice-btn{font-size:10px;padding:7px 8px}.head-actions{max-width:155px}.review-summary>div:first-child{display:block}.review-summary>div:first-child span{display:block;margin-top:3px}}

/* ChessPicker v2 immersive game window, mistake tree and voice */
.tree-family{padding:10px 8px 5px;font-size:10px;font-weight:950;letter-spacing:.08em;text-transform:uppercase;color:#6a7f91}.opening-tree-node{min-width:0}.mistake-subtree{margin:-2px 0 7px 13px;padding:5px 0 5px 8px;border-left:2px solid #d9e5ef;display:grid;gap:4px}.mistake-subtree button{width:100%;text-align:left;border:1px solid #dbe5ee;background:#f8fafc;color:#3f5366;border-radius:8px;padding:7px 8px;font-size:10px;font-weight:800;cursor:pointer}.mistake-subtree .tree-mistake{border-color:#f0d6cb;background:#fff8f4;color:#7b412a}.mistake-subtree button.active{background:#12355b;color:#fff;border-color:#12355b}.teacher-title{gap:8px;flex-wrap:wrap}.teacher-audio{display:flex;align-items:center;justify-content:flex-end;gap:5px;margin-left:auto;flex-wrap:wrap}.teacher-audio button,.teacher-audio label{border:1px solid #cddbe7;background:#fff;border-radius:8px;padding:6px 8px;font-size:10px;font-weight:850;color:#284b69}.teacher-audio label{display:flex;align-items:center;gap:4px}.teacher-audio input{margin:0}
body.game-open{overflow:hidden}.immersive-play{position:fixed!important;inset:0!important;z-index:9999!important;margin:0!important;padding:14px!important;border:0!important;border-radius:0!important;background:rgba(7,18,29,.88)!important;overflow:auto!important;display:grid!important;place-items:start center!important}.immersive-play[hidden]{display:none!important}.play-window{position:relative;width:min(1460px,100%);background:#f7fafc;border:1px solid #b9cddd;border-radius:18px;padding:14px;box-shadow:0 24px 80px rgba(0,0,0,.38);overflow:hidden}.play-window .play-head{padding:2px 2px 10px;border-bottom:1px solid #dce6ee}.arena-settings{display:grid;grid-template-columns:130px 170px 120px minmax(190px,1fr) auto;gap:8px;align-items:end;padding:11px 0}.arena-settings label{font-size:10px;text-transform:uppercase;font-weight:900;color:#5c7082}.arena-settings select{display:block;width:100%;margin-top:4px;border:1px solid #cbd8e2;border-radius:9px;background:#fff;padding:9px;font-weight:800;color:#1f3f5a}.arena-layout{display:grid;grid-template-columns:minmax(420px,820px) minmax(280px,1fr);gap:15px;align-items:start}.arena-board-side{min-width:0}.arena-board-side .board-wrap{width:min(72vw,calc(100vh - 245px));max-width:100%;margin:auto;position:relative}.clock-row{display:grid;grid-template-columns:1fr 1fr;gap:8px;margin-bottom:8px}.clock-box{display:flex;justify-content:space-between;align-items:center;background:#e9eff4;border:2px solid transparent;border-radius:10px;padding:7px 11px;color:#3e5264}.clock-box span{font-size:11px;font-weight:900}.clock-box b{font:900 23px/1.1 ui-monospace,SFMono-Regular,Consolas,monospace}.clock-box.active-clock{border-color:#12355b;background:#fff}.arena-side{min-width:0;background:#fff;border:1px solid #dbe5ec;border-radius:13px;padding:12px}.no-undo{background:#fff2d8;border:1px solid #f0d5a2;border-radius:10px;padding:9px;font-size:11px;color:#704e16;margin-bottom:9px}.review-actions{display:grid;grid-template-columns:1fr;gap:6px;margin-top:8px}.review-actions button{border:1px solid #cbd8e2;background:#eef5fb;color:#234a68;border-radius:9px;padding:9px;font-weight:850}.moving-piece{position:absolute!important;z-index:80!important;object-fit:contain!important;pointer-events:none!important;transition:transform 240ms cubic-bezier(.2,.8,.2,1)!important;will-change:transform}.start-flash{position:absolute;inset:0;z-index:100;background:rgba(255,255,255,.94);display:grid;place-content:center;text-align:center;color:#12355b}.start-flash[hidden]{display:none}.start-flash strong{font-size:clamp(34px,7vw,84px);letter-spacing:.08em}.start-flash span{font-weight:850;color:#436078}.start-flash.go{animation:startFlash .9s ease both}@keyframes startFlash{0%{opacity:0;transform:scale(.92)}18%{opacity:1;transform:scale(1.03)}65%{opacity:1;transform:scale(1)}100%{opacity:0;transform:scale(1.04)}}
@media(max-width:1000px){.arena-settings{grid-template-columns:1fr 1fr 1fr}.arena-settings label:nth-child(4){grid-column:1/3}.arena-settings .primary-action{grid-column:3}.arena-layout{grid-template-columns:1fr}.arena-board-side .board-wrap{width:min(92vw,680px)}.arena-side{max-width:760px;margin:auto;width:100%}}
@media(max-width:650px){.immersive-play{padding:5px!important}.play-window{padding:8px;border-radius:12px}.arena-settings{grid-template-columns:1fr 1fr}.arena-settings label:nth-child(4){grid-column:1/-1}.arena-settings .primary-action{grid-column:1/-1}.arena-board-side .board-wrap{width:min(96vw,560px)}.clock-box b{font-size:18px}.play-head h2{font-size:18px}.play-head p{font-size:10px}.teacher-audio{width:100%;justify-content:flex-start}.mistake-subtree{margin-left:6px}}
@media(prefers-reduced-motion:reduce){.moving-piece{transition:none!important}.start-flash.go{animation:none}}
/* ChessPicker v2.1 reliability + mistake tree */
.mistake-tree{margin:3px 7px 8px 18px;border-left:2px solid #d9e4ec;padding-left:7px}.mistake-tree summary{cursor:pointer;list-style:none;font-size:11px;font-weight:900;color:#744a10;padding:6px 7px;border-radius:7px;background:#fff6e4}.mistake-tree summary::-webkit-details-marker{display:none}.mistake-tree summary:before{content:'▸ ';}.mistake-tree[open] summary:before{content:'▾ ';}.mistake-subtree{display:grid;gap:4px;padding:5px 0}.mistake-subtree button{width:100%;text-align:left;border:1px solid #dce5ec;background:#fff;border-radius:7px;padding:7px 8px;font-size:11px;color:#29465e;cursor:pointer}.mistake-subtree button.active{background:#eaf3fb;border-color:#7fa4c0;font-weight:900}.play-window.game-running{outline:3px solid rgba(18,53,91,.14)}.game-running #startPlay{background:#214f73}.game-running #playBoardSlot .sq{cursor:pointer}.game-running #playBoardSlot .sq.selected{box-shadow:inset 0 0 0 4px rgba(255,193,7,.72)}

/* ChessPicker v3 categorized libraries */
.category-tree{border:1px solid #dbe5ee;border-radius:10px;background:#fff;margin:5px 0;overflow:hidden}.category-tree>summary{list-style:none;cursor:pointer;display:flex;align-items:center;justify-content:space-between;gap:8px;padding:9px 10px;font-size:12px;font-weight:900;color:#173d61;background:#eef5fb}.category-tree>summary::-webkit-details-marker{display:none}.category-tree>summary:before{content:"▸";margin-right:4px}.category-tree[open]>summary:before{content:"▾"}.category-tree>summary span{flex:1}.category-tree>summary b{background:#fff;border:1px solid #d4e1eb;border-radius:999px;padding:2px 7px;font-size:10px}.category-kids{padding:5px}.category-kids .opening-tree-node{margin-bottom:3px}.category-kids .opening-item{width:100%}.course-switch:before{content:"STUDY:";font-size:10px;font-weight:950;letter-spacing:.1em;color:#547086;margin-right:2px}.teacher-card{border-width:2px}.teacher-card .think{box-shadow:inset 3px 0 0 #d69b2d}.board-column>.board-wrap{display:block!important;visibility:visible!important;opacity:1!important}.game-open .arena-board-side .board-wrap{display:block!important}.course-btn[data-course="Middlegames"]{border-style:solid}.course-btn[data-course="Endgames"]{border-style:solid}
@media(max-width:760px){.category-tree>summary{padding:8px;font-size:11px}.category-kids{padding:3px}.course-switch{gap:5px}.course-btn{white-space:nowrap}.course-switch{overflow-x:auto;flex-wrap:nowrap}.course-switch>span{display:none}}

/* ChessPicker Academy v4 */
.course-switch{position:sticky;top:54px;z-index:15;gap:10px;background:rgba(255,255,255,.96);backdrop-filter:blur(10px);border-bottom:1px solid #dfe8f1;padding:10px max(18px,calc((100vw - 1460px)/2));}
.course-switch .course-btn{min-width:150px;font-size:14px}.course-switch .course-btn.active{box-shadow:0 6px 18px rgba(18,53,91,.18)}
.academy-menu{display:grid;grid-template-columns:1fr;gap:8px;margin:10px 0 12px;padding:10px;border:1px solid #dce7f2;background:#f8fbff;border-radius:12px}.academy-menu label span{display:block;font-size:10px;font-weight:800;letter-spacing:.05em;color:#53697f;margin-bottom:4px;text-transform:uppercase}.academy-menu select{width:100%;height:38px;border:1px solid #cbd9e7;border-radius:9px;background:#fff;padding:0 9px;color:#173957;font-weight:700}.repertoire-hint{min-height:20px;font-size:11px;font-weight:800;color:#0b6b50;padding:2px 3px}.category-tree>summary{background:#edf4fb;border-left:4px solid #1e6fb2}.category-tree:nth-of-type(3n+2)>summary{background:#f3f7ea;border-left-color:#6d8d3c}.category-tree:nth-of-type(3n)>summary{background:#fff3e6;border-left-color:#c77716}.mistake-tree>summary{background:#fff4df!important}.teacher-card{border-top:4px solid #1a6da8}.teacher-card .think{background:#fff8e9;border:1px solid #f0d9a7}.method-card{margin-top:14px;padding:14px 16px;border-radius:14px;background:#eef6ff;border:1px solid #cfe1f1}.method-card strong{color:#12355b}.method-card p{margin:.35rem 0 0}.opening-item small{white-space:normal;line-height:1.25}.opening-list{scrollbar-width:thin}
@media(min-width:1180px){.academy-menu{grid-template-columns:1fr}.learning-shell{grid-template-columns:minmax(270px,320px) minmax(0,1fr)}.viewer-grid{grid-template-columns:minmax(540px,1.15fr) minmax(420px,.85fr)}.board-wrap{max-width:min(72vh,760px)}}
@media(max-width:780px){.course-switch{top:48px;overflow-x:auto;white-space:nowrap}.course-switch .course-btn{min-width:auto}.academy-menu{padding:8px}.viewer-grid{display:block}.board-wrap{width:min(100%,calc(100vw - 22px));max-width:none}.study-column{margin-top:12px}}

/* ChessPicker Academy v4 */
.course-switch{position:sticky;top:54px;z-index:15;gap:10px;background:rgba(255,255,255,.96);backdrop-filter:blur(10px);border-bottom:1px solid #dfe8f1;padding:10px max(18px,calc((100vw - 1460px)/2));}
.course-switch .course-btn{min-width:150px;font-size:14px}.course-switch .course-btn.active{box-shadow:0 6px 18px rgba(18,53,91,.18)}
.academy-menu{display:grid;grid-template-columns:1fr;gap:8px;margin:10px 0 12px;padding:10px;border:1px solid #dce7f2;background:#f8fbff;border-radius:12px}.academy-menu label span{display:block;font-size:10px;font-weight:800;letter-spacing:.05em;color:#53697f;margin-bottom:4px;text-transform:uppercase}.academy-menu select{width:100%;height:38px;border:1px solid #cbd9e7;border-radius:9px;background:#fff;padding:0 9px;color:#173957;font-weight:700}.repertoire-hint{min-height:20px;font-size:11px;font-weight:800;color:#0b6b50;padding:2px 3px}.category-tree>summary{background:#edf4fb;border-left:4px solid #1e6fb2}.category-tree:nth-of-type(3n+2)>summary{background:#f3f7ea;border-left-color:#6d8d3c}.category-tree:nth-of-type(3n)>summary{background:#fff3e6;border-left-color:#c77716}.mistake-tree>summary{background:#fff4df!important}.teacher-card{border-top:4px solid #1a6da8}.teacher-card .think{background:#fff8e9;border:1px solid #f0d9a7}.method-card{margin-top:14px;padding:14px 16px;border-radius:14px;background:#eef6ff;border:1px solid #cfe1f1}.method-card strong{color:#12355b}.method-card p{margin:.35rem 0 0}.opening-item small{white-space:normal;line-height:1.25}.opening-list{scrollbar-width:thin}
@media(min-width:1180px){.academy-menu{grid-template-columns:1fr}.learning-shell{grid-template-columns:minmax(270px,320px) minmax(0,1fr)}.viewer-grid{grid-template-columns:minmax(540px,1.15fr) minmax(420px,.85fr)}.board-wrap{max-width:min(72vh,760px)}}
@media(max-width:780px){.course-switch{top:48px;overflow-x:auto;white-space:nowrap}.course-switch .course-btn{min-width:auto}.academy-menu{padding:8px}.viewer-grid{display:block}.board-wrap{width:min(100%,calc(100vw - 22px));max-width:none}.study-column{margin-top:12px}}

/* ChessPicker Academy v4 */
.course-switch{position:sticky;top:54px;z-index:15;gap:10px;background:rgba(255,255,255,.96);backdrop-filter:blur(10px);border-bottom:1px solid #dfe8f1;padding:10px max(18px,calc((100vw - 1460px)/2));}
.course-switch .course-btn{min-width:150px;font-size:14px}.course-switch .course-btn.active{box-shadow:0 6px 18px rgba(18,53,91,.18)}
.academy-menu{display:grid;grid-template-columns:1fr;gap:8px;margin:10px 0 12px;padding:10px;border:1px solid #dce7f2;background:#f8fbff;border-radius:12px}.academy-menu label span{display:block;font-size:10px;font-weight:800;letter-spacing:.05em;color:#53697f;margin-bottom:4px;text-transform:uppercase}.academy-menu select{width:100%;height:38px;border:1px solid #cbd9e7;border-radius:9px;background:#fff;padding:0 9px;color:#173957;font-weight:700}.repertoire-hint{min-height:20px;font-size:11px;font-weight:800;color:#0b6b50;padding:2px 3px}.category-tree>summary{background:#edf4fb;border-left:4px solid #1e6fb2}.category-tree:nth-of-type(3n+2)>summary{background:#f3f7ea;border-left-color:#6d8d3c}.category-tree:nth-of-type(3n)>summary{background:#fff3e6;border-left-color:#c77716}.mistake-tree>summary{background:#fff4df!important}.teacher-card{border-top:4px solid #1a6da8}.teacher-card .think{background:#fff8e9;border:1px solid #f0d9a7}.method-card{margin-top:14px;padding:14px 16px;border-radius:14px;background:#eef6ff;border:1px solid #cfe1f1}.method-card strong{color:#12355b}.method-card p{margin:.35rem 0 0}.opening-item small{white-space:normal;line-height:1.25}.opening-list{scrollbar-width:thin}
@media(min-width:1180px){.academy-menu{grid-template-columns:1fr}.learning-shell{grid-template-columns:minmax(270px,320px) minmax(0,1fr)}.viewer-grid{grid-template-columns:minmax(540px,1.15fr) minmax(420px,.85fr)}.board-wrap{max-width:min(72vh,760px)}}
@media(max-width:780px){.course-switch{top:48px;overflow-x:auto;white-space:nowrap}.course-switch .course-btn{min-width:auto}.academy-menu{padding:8px}.viewer-grid{display:block}.board-wrap{width:min(100%,calc(100vw - 22px));max-width:none}.study-column{margin-top:12px}}
.pgn-library-link{display:inline-flex;align-items:center;justify-content:center;text-decoration:none}

/* v6 safety: hidden computer arena must always close */
#playPanel[hidden]{display:none!important}

/* ChessPicker v7: computer arena close + non-overlapping Middlegame/Endgame menus */
#playPanel.easy-closed,#playPanel.easy-closed[hidden],#playPanel[aria-hidden="true"]{display:none!important;visibility:hidden!important;pointer-events:none!important;opacity:0!important}
#closePlay{position:relative;z-index:1000001;pointer-events:auto!important;touch-action:manipulation}
.library-panel{min-width:0;overflow:hidden}
.academy-menu,.academy-menu label,.academy-menu select,.opening-list,.category-tree,.category-kids,.opening-tree-node,.opening-item{min-width:0;max-width:100%}
.academy-menu select{display:block;width:100%;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.category-tree>summary{min-width:0;overflow:hidden}
.category-tree>summary span{min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.category-tree>summary b{flex:0 0 auto}
.opening-item{overflow:hidden}
.opening-item strong,.opening-item small{overflow-wrap:anywhere;word-break:normal}
.opening-list{overflow-x:hidden!important;padding-right:2px}
@media(min-width:1180px){
  .learning-shell{grid-template-columns:minmax(340px,365px) minmax(0,1fr)}
  .library-panel.compact-training-menu{padding:16px}
  .viewer-grid{grid-template-columns:minmax(500px,1.15fr) minmax(390px,.85fr)}
}
@media(max-width:1179px) and (min-width:781px){
  .learning-shell{grid-template-columns:minmax(300px,335px) minmax(0,1fr)}
  .viewer-grid{grid-template-columns:minmax(460px,1fr) minmax(330px,.78fr)}
}

/* ChessPicker Academy v8 training lab */
.v8-tools{margin:0 16px 14px;border:1px solid #d7e3ee;border-radius:14px;background:#f8fbfe;overflow:hidden}.v8-tool-head{display:flex;justify-content:space-between;gap:12px;align-items:center;padding:11px 13px;border-bottom:1px solid #e2eaf1}.v8-tool-head>div{display:flex;gap:9px;align-items:center;flex-wrap:wrap}.v8-health{font-size:10px;font-weight:900;border-radius:999px;padding:4px 8px}.v8-health.ok{background:#e8f6ef;color:#19623e}.v8-health.warn{background:#fff4df;color:#8a5b00}.v8-progress span{font-size:11px;font-weight:800;color:#53697f}.v8-actions{display:flex;gap:7px;flex-wrap:wrap;padding:10px 12px}.v8-actions button,.v8-train-actions button,.v8-explorer button,.v8-result button{border:1px solid #c7d7e5;background:#fff;color:#173d61;border-radius:9px;padding:8px 10px;font-weight:800;cursor:pointer}.v8-actions button:first-child{background:#12355b;color:#fff;border-color:#12355b}.v8-actions button:disabled{opacity:.45;cursor:not-allowed}.v8-panel{border-top:1px solid #dfe8f0;background:#fff;padding:12px}.v8-train{display:flex;justify-content:space-between;align-items:center;gap:16px}.v8-train h3,.v8-explorer h3,.v8-test h3{margin:.2rem 0}.v8-train p,.v8-explorer p,.v8-test p,.v8-result p{margin:.35rem 0;color:#53697f}.v8-train-actions{display:flex;gap:7px;flex-wrap:wrap}.v8-result.good{border-left:4px solid #29865b;padding-left:10px}.v8-explorer-list{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:7px;margin:10px 0}.v8-explorer-list button{text-align:left;display:flex;flex-direction:column;gap:3px}.v8-explorer-list span{font-size:10px;color:#607488;font-weight:700}.v8-test{max-width:760px}.v8-tools .eyebrow{font-size:9px}.v8-tools + .viewer-grid{padding-top:0}.v8-tools .sq{cursor:pointer}
@media(max-width:780px){.v8-tools{margin:0 8px 10px}.v8-tool-head,.v8-train{align-items:flex-start;flex-direction:column}.v8-actions{display:grid;grid-template-columns:1fr 1fr}.v8-actions button{min-height:44px}.v8-explorer-list{grid-template-columns:1fr}}
/* v9 stability + large-course menu */
html{overflow-anchor:none}.viewer-panel,.viewer-grid,.board-column,.board-wrap{overflow-anchor:none}.move-list{overscroll-behavior:contain}.v9-group{margin-bottom:8px}.v9-subgroup{margin:4px 0;background:#fbfdff}.v9-subgroup>summary{font-size:11px;background:#f7fafc!important;border-left-width:3px!important}.copyright-note{grid-column:1/-1}.play-panel:not([hidden]) #board img[draggable="true"]{cursor:grab}.play-panel:not([hidden]) #board img[draggable="true"]:active{cursor:grabbing}.play-panel:not([hidden]) #board .sq{cursor:default}
/* ChessPicker v10 */
#boardWrap{position:relative}.chess-board{position:relative;z-index:1}#v10Arrows{position:absolute;inset:0;width:100%;height:100%;z-index:4;pointer-events:none;overflow:visible}#v10Arrows marker path{fill:rgba(16,122,79,.95)}.v10-next-arrow{stroke:rgba(16,122,79,.90);stroke-width:12;stroke-linecap:round;filter:drop-shadow(0 2px 3px rgba(0,0,0,.28));animation:v10ArrowPulse 1.15s ease-in-out infinite}.v10-target{fill:none;stroke:rgba(16,122,79,.8);stroke-width:5;animation:v10TargetPulse 1.15s ease-in-out infinite;transform-box:fill-box;transform-origin:center}@keyframes v10ArrowPulse{0%,100%{opacity:.55}50%{opacity:1}}@keyframes v10TargetPulse{0%,100%{opacity:.35;transform:scale(.8)}50%{opacity:1;transform:scale(1.15)}}
.teacher-audio{display:flex;gap:6px;align-items:center;flex-wrap:wrap}.teacher-audio button{white-space:nowrap}
.v10-tree-family,.v10-tree-sub,.v10-tree-variation,.v10-mistakes{border:1px solid rgba(18,53,91,.13);border-radius:10px;background:#fff;margin:6px 0;overflow:hidden}.v10-tree-family>summary,.v10-tree-sub>summary,.v10-tree-variation>summary,.v10-mistakes>summary{cursor:pointer;display:flex;justify-content:space-between;gap:8px;align-items:center;padding:10px 12px;font-weight:800;list-style:none}.v10-tree-family>summary{background:#eef4fa;color:#12355b}.v10-tree-sub>summary{background:#f7f9fc}.v10-tree-variation>summary{font-size:.94rem}.v10-tree-family summary::-webkit-details-marker,.v10-tree-sub summary::-webkit-details-marker,.v10-tree-variation summary::-webkit-details-marker,.v10-mistakes summary::-webkit-details-marker{display:none}.v10-tree-family summary b,.v10-tree-sub summary b,.v10-tree-variation summary b{font-size:.72rem;padding:2px 7px;border-radius:999px;background:rgba(18,53,91,.08)}.v10-tree-body,.v10-tree-lessons,.v10-tree-actions,.v10-mistakes>div{padding:5px 8px 8px}.v10-tree-item,.v10-mistake-item{width:100%;text-align:left;border:0;border-radius:8px;background:transparent;padding:8px 9px;margin:2px 0;cursor:pointer}.v10-tree-item:hover,.v10-mistake-item:hover{background:#f3f7fb}.v10-tree-item.active,.v10-mistake-item.active{background:#dceafa;box-shadow:inset 3px 0 #12355b}.v10-tree-item strong,.v10-mistake-item strong{display:block}.v10-tree-item small,.v10-mistake-item small{display:block;opacity:.72;margin-top:2px;line-height:1.25}.v10-mistake-item small{font-size:.72rem}
.v10-drag-board img[draggable="true"]{cursor:grab;user-select:none;-webkit-user-drag:element}.v10-drag-board img[draggable="true"]:active{cursor:grabbing}.v10-drag-board .drag-source{opacity:.68}.v10-drag-board .drag-over{box-shadow:inset 0 0 0 5px rgba(16,122,79,.58)}
/* v11 consolidated academy fixes */
.fatal-chess-error{position:sticky;top:0;z-index:99999;background:#7f1d1d;color:#fff;padding:12px 18px;display:flex;gap:14px;align-items:center;justify-content:center;flex-wrap:wrap}
#boardWrap{position:relative}.v11-arrow-layer{position:absolute;inset:0;width:100%;height:100%;pointer-events:none;z-index:7;overflow:visible}.v11-road{stroke:#f59e0b;stroke-width:7;stroke-linecap:round;opacity:.88;filter:drop-shadow(0 2px 3px rgba(0,0,0,.4));animation:v11pulse 1.1s ease-in-out infinite}.v11-arrow-layer marker path{fill:#f59e0b}.v11-target{fill:none;stroke:#22c55e;stroke-width:5;animation:v11target 1.1s ease-in-out infinite}@keyframes v11pulse{50%{opacity:.42;stroke-width:10}}@keyframes v11target{50%{r:21;opacity:.35}}
.v11-tree,.v11-tree-sub,.v11-variation{border:1px solid #d9e2ec;border-radius:10px;background:#fff;margin:7px 0;overflow:hidden}.v11-tree>summary,.v11-tree-sub>summary,.v11-variation>summary{cursor:pointer;display:flex;justify-content:space-between;gap:8px;align-items:center;padding:10px 12px;font-weight:800}.v11-tree>summary b,.v11-tree-sub>summary b,.v11-variation>summary b{font-size:11px;background:#e8eef6;border-radius:999px;padding:3px 7px}.v11-tree-body,.v11-tree-kids,.v11-actions{padding:5px 8px 9px}.v11-tree-item,.v11-mistake{width:100%;text-align:left;border:0;background:#f7f9fc;border-radius:8px;padding:9px 10px;margin:4px 0;cursor:pointer}.v11-tree-item strong,.v11-mistake strong{display:block}.v11-tree-item small,.v11-mistake small{display:block;color:#62748a;margin-top:2px}.v11-tree-item.active,.v11-mistake.active{outline:2px solid #12355b;background:#eaf2fb}.v11-mistake{background:#fff7ed}.v11-drag-board img[draggable="true"]{cursor:grab}.v11-drag-board .drag-source img{cursor:grabbing;opacity:.72}.v11-drag-board .drag-over{box-shadow:inset 0 0 0 5px rgba(34,197,94,.75)}

/* V13 smart opening search */
.search-smart-hint,.search-empty{padding:10px 12px;margin:6px 0 10px;border-radius:10px;background:rgba(127,127,127,.08);font-size:.9rem}.search-smart-hint strong,.search-empty strong{display:block;margin-bottom:2px}.search-empty small{display:block;opacity:.78}.search-result-node .opening-item small{white-space:normal}

/* V18: long Endgame course menu — visible scrolling + stable lesson numbers */
.opening-list.endgame-scroll{
  max-height:calc(100vh - 245px)!important;
  min-height:360px;
  overflow-y:scroll!important;
  overflow-x:hidden!important;
  overscroll-behavior:contain;
  scrollbar-gutter:stable;
  padding-right:6px;
}
.opening-list.endgame-scroll::-webkit-scrollbar{width:11px}
.opening-list.endgame-scroll::-webkit-scrollbar-thumb{background:#aebdcb;border:3px solid #f8fafc;border-radius:999px}
.opening-list.endgame-scroll::-webkit-scrollbar-track{background:#eef3f7;border-radius:999px}
.endgame-numbered-item strong{display:flex!important;align-items:flex-start;gap:5px}
.endgame-number{display:inline-block;flex:0 0 32px;min-width:32px;color:#0f5f9f;font-variant-numeric:tabular-nums;font-weight:950}
.endgame-tree>summary{position:sticky;top:0;z-index:2}
@media(max-width:780px){.opening-list.endgame-scroll{max-height:62vh!important;min-height:300px}}

/* V19: Endgame lesson list gets its OWN scroll area, so 1..100 are always reachable. */
.opening-list.endgame-scroll{
  max-height:none!important;
  min-height:0!important;
  overflow:visible!important;
  padding-right:0!important;
}
.endgame-tree,.endgame-subtree{overflow:visible!important}
.endgame-group-body{padding-bottom:8px!important}
.endgame-lessons-wrap{padding:4px 7px 9px}
.endgame-lessons-scroll{
  display:block!important;
  height:min(58vh,620px)!important;
  min-height:280px;
  overflow-y:auto!important;
  overflow-x:hidden!important;
  overscroll-behavior:contain;
  touch-action:pan-y;
  -webkit-overflow-scrolling:touch;
  scrollbar-gutter:stable;
  padding:2px 7px 10px 2px!important;
  border:1px solid #dbe5ee;
  border-radius:10px;
  background:#fbfdff;
}
.endgame-lessons-scroll::-webkit-scrollbar{width:12px}
.endgame-lessons-scroll::-webkit-scrollbar-thumb{background:#879caf;border:3px solid #fbfdff;border-radius:999px}
.endgame-lessons-scroll::-webkit-scrollbar-track{background:#edf2f6;border-radius:999px}
.endgame-numbered-item{display:block!important;width:100%!important;margin:3px 0!important}
.endgame-numbered-item strong{display:grid!important;grid-template-columns:42px minmax(0,1fr);align-items:start;gap:4px}
.endgame-number{min-width:42px!important;width:42px!important;text-align:right;padding-right:5px}
.endgame-name{min-width:0;white-space:normal;overflow-wrap:anywhere}
.endgame-numbered-item small{margin-left:46px!important}
.endgame-jump-row{position:sticky;top:0;z-index:6;display:flex;align-items:center;gap:6px;padding:5px 1px 8px;background:#fff}
.endgame-jump-row label{display:flex;align-items:center;gap:6px;min-width:0;flex:1;font-size:11px;font-weight:800;color:#52667b}
.endgame-jump-select{min-width:0;flex:1;max-width:205px;padding:6px;border:1px solid #ccd8e3;border-radius:8px;background:#fff;color:#183a5a}
.endgame-jump-row button{border:0;border-radius:8px;background:#12355b;color:#fff;padding:7px 10px;font-weight:800;cursor:pointer}
@media(max-width:780px){
  .endgame-lessons-scroll{height:56vh!important;min-height:260px!important}
  .endgame-jump-select{max-width:170px}
}


/* ChessPicker v20 simple piece-wise Endgame tree */
.opening-list.endgame-simple-root{
  max-height:72vh!important;
  overflow-y:auto!important;
  overflow-x:hidden!important;
  overscroll-behavior:contain;
  scroll-behavior:smooth;
  -webkit-overflow-scrolling:touch;
  padding-right:4px;
}
.endgame-simple-root::-webkit-scrollbar,.endgame-simple-list::-webkit-scrollbar{width:10px}
.endgame-simple-root::-webkit-scrollbar-thumb,.endgame-simple-list::-webkit-scrollbar-thumb{background:#9aabba;border:2px solid #f7fafc;border-radius:999px}
.endgame-simple-root::-webkit-scrollbar-track,.endgame-simple-list::-webkit-scrollbar-track{background:#edf2f6;border-radius:999px}
.endgame-simple-category{margin:0 0 8px!important;overflow:visible!important}
.endgame-simple-category>summary{position:sticky;top:0;z-index:3;background:#f7fafc;cursor:pointer}
.endgame-simple-list{
  max-height:54vh!important;
  min-height:140px;
  overflow-y:auto!important;
  overflow-x:hidden!important;
  scroll-behavior:smooth;
  overscroll-behavior:contain;
  -webkit-overflow-scrolling:touch;
  padding:5px 7px 9px;
}
.endgame-simple-item{display:block!important;width:100%!important;margin:3px 0!important;text-align:left!important}
.endgame-simple-item strong{display:grid!important;grid-template-columns:72px minmax(0,1fr);gap:8px;align-items:start!important}
.endgame-game-no{font-variant-numeric:tabular-nums;color:#0f5f9f;font-weight:950;white-space:nowrap}
.endgame-game-name{white-space:normal;overflow-wrap:anywhere;min-width:0}
@media(max-width:780px){
  .opening-list.endgame-simple-root{max-height:65vh!important}
  .endgame-simple-list{max-height:50vh!important;min-height:220px}
  .endgame-simple-item strong{grid-template-columns:68px minmax(0,1fr)}
}

/* ChessPicker v22 — Endgame rank direction + start-position outcome */
.endgame-rank-direction .coord.rank{font-size:13px!important;font-weight:950!important;line-height:1!important;padding:2px 3px;border-radius:4px;background:rgba(255,255,255,.72);color:#173d61!important;text-shadow:none!important;z-index:5!important}
.endgame-rank-direction .coord.file{font-size:11px!important;font-weight:900!important}
.endgame-outcome{display:grid;grid-template-columns:auto auto 1fr;align-items:center;gap:9px;width:100%;margin:-2px 0 12px;padding:10px 13px;border:1px solid #cfdde8;border-radius:12px;background:#f7fafc;color:#173d61;box-shadow:0 4px 12px rgba(18,53,91,.05)}
.endgame-outcome[hidden]{display:none!important}.endgame-outcome span{font-size:9px;font-weight:950;letter-spacing:.1em;color:#61788c}.endgame-outcome strong{font-size:22px;line-height:1;color:#12355b}.endgame-outcome b{font-size:13px}.endgame-outcome.white-win{background:#f1fbf5;border-color:#b9dfc8}.endgame-outcome.black-win{background:#f5f6f8;border-color:#c8d0d8}.endgame-outcome.draw{background:#fff9eb;border-color:#ead8a8}.endgame-outcome.checking{opacity:.82}
@media(max-width:650px){.endgame-outcome{grid-template-columns:auto 1fr;gap:5px 8px}.endgame-outcome span{grid-column:1/-1}.endgame-outcome strong{font-size:20px}.endgame-outcome b{font-size:12px}}
/* V12 Academy Coach */
.academy-path{display:flex;gap:6px;flex-wrap:wrap;padding:10px max(18px,calc((100vw - 1460px)/2));background:#f5f9fd;border-bottom:1px solid #dce7f1}.academy-path button,.coach-tools button{border:1px solid #c9d8e6;background:#fff;color:#173d61;border-radius:9px;padding:8px 12px;font-weight:800;cursor:pointer}.academy-path button:hover,.coach-tools button:hover{background:#eaf4ff}.progress-dashboard{margin:0 auto 12px;max-width:1460px;padding:12px 18px}.progress-grid{display:grid;grid-template-columns:repeat(6,1fr);gap:8px}.progress-grid>div{background:#fff;border:1px solid #dce6ef;border-radius:12px;padding:10px;text-align:center}.progress-grid b{display:block;font-size:20px;color:#12355b}.progress-grid span{font-size:10px;color:#637487}.coach-tools{display:flex;gap:7px;margin:9px 0}.coach-grid{display:grid;grid-template-columns:1fr 1fr;gap:8px;margin:8px 0}.coach-grid>div{padding:10px;border-radius:10px;background:#f5f9fd;border:1px solid #dce7f1}.coach-grid b{font-size:12px;color:#173d61}.coach-grid p{font-size:12px;line-height:1.5;margin:5px 0 0}.coach-grid .coach-wrong{background:#fff7ed}.coach-grid .coach-memory{background:#eefaf2}.lesson-goal{display:inline-block;margin-top:6px;padding:5px 9px;border-radius:999px;background:#eaf7ee;color:#14633c;font-size:11px}.coach-highlight{box-shadow:inset 0 0 0 5px #f3b51b!important}.best-move-quiz{position:fixed;inset:0;z-index:10000;background:rgba(7,25,42,.64);display:grid;place-items:center;padding:18px}.best-move-quiz[hidden]{display:none}.best-move-quiz>div{width:min(520px,94vw);background:#fff;border-radius:16px;padding:20px;box-shadow:0 20px 60px #0005}.best-move-quiz button{padding:9px 12px;margin:4px;border:1px solid #cbd9e6;border-radius:8px;background:#fff;font-weight:800}.quiz-correct{color:#147548}.quiz-wrong{color:#b23a32}@media(max-width:760px){.progress-grid{grid-template-columns:repeat(2,1fr)}.coach-grid{grid-template-columns:1fr}.academy-path{overflow-x:auto;flex-wrap:nowrap}.academy-path button{white-space:nowrap}}

/* V15 stable PGN board */
.board-wrap{contain:layout paint;flex:0 0 auto}.chess-board{grid-template-columns:repeat(8,minmax(0,1fr))!important;grid-template-rows:repeat(8,minmax(0,1fr))!important}.chess-board>.sq{min-width:0;min-height:0;overflow:hidden}.chess-board>.sq img{max-width:100%;max-height:100%}
#quizBox{display:none!important}

/* V16 real opening example games */
.famous-select{width:100%;min-height:44px;font-weight:750}
.famous-meta{min-height:24px;padding-top:5px;font-size:13px;line-height:1.35}

/* V21 Famous-game PGN study and analysis */
.famous-study-tools{margin:12px 0 16px;padding:14px;border:1px solid #d8e1eb;border-radius:14px;background:#f8fbff}.famous-study-head{display:flex;justify-content:space-between;gap:12px;align-items:center;margin-bottom:10px}.famous-study-head div{display:flex;flex-direction:column}.famous-study-head small{color:#637083}.famous-study-head>span{font-size:12px;color:#4b6076;text-align:right}.famous-study-actions{display:flex;gap:8px;flex-wrap:wrap}.famous-study-actions button{border:1px solid #c5d2df;background:white;border-radius:9px;padding:9px 12px;font-weight:700;cursor:pointer}.famous-study-actions .primary-study{background:#173f68;color:white;border-color:#173f68}.famous-study-actions .analyze-study{background:#0d6b50;color:white;border-color:#0d6b50}.famous-study-actions button:disabled{opacity:.5;cursor:not-allowed}.famous-analysis-panel{margin-top:14px;border-top:1px solid #d8e1eb;padding-top:14px}.analysis-summary>div:first-child{display:flex;justify-content:space-between;gap:10px}.analysis-summary>div:first-child span{font-weight:800}.analysis-badges{display:flex;gap:6px;flex-wrap:wrap;margin:9px 0}.analysis-grade{display:inline-flex;align-items:center;border-radius:999px;padding:3px 8px;font-size:11px;font-weight:900;background:#e8eef4;color:#22384d}.analysis-grade.Best,.analysis-grade.Excellent{background:#dff3e7;color:#176239}.analysis-grade.Good{background:#e7f2fb;color:#245d82}.analysis-grade.Inaccuracy{background:#fff3cf;color:#7b5b00}.analysis-grade.Mistake,.analysis-grade.Missed-Chance{background:#ffe7c5;color:#8a4f00}.analysis-grade.Blunder{background:#ffe0e0;color:#9d2020}.analysis-progress{margin:10px 0}.analysis-progress strong,.analysis-progress span{font-size:12px}.analysis-progress span{float:right}.analysis-progress>div{height:7px;background:#dce5ee;border-radius:99px;overflow:hidden;clear:both;margin-top:5px}.analysis-progress i{display:block;height:100%;background:currentColor;width:0}.analysis-filter{display:flex;gap:6px;flex-wrap:wrap;margin:10px 0}.analysis-filter button{border:1px solid #cbd6e0;background:white;border-radius:999px;padding:5px 9px;cursor:pointer}.analysis-filter button.active{background:#203f5e;color:white}.analysis-list{display:grid;gap:7px;max-height:540px;overflow:auto;padding-right:2px}.famous-review-row{text-align:left;border:1px solid #dbe3eb;background:white;border-radius:10px;padding:10px;cursor:pointer;display:flex;flex-direction:column;gap:4px}.famous-review-row:hover{border-color:#7c9bb8;background:#f8fbfe}.review-move{display:flex;justify-content:space-between;gap:10px}.famous-review-row small{color:#56677a;line-height:1.35}.analysis-note,.analysis-empty{font-size:11px;color:#6c7886}.sq.analysis-from{box-shadow:inset 0 0 0 5px rgba(27,112,174,.55)}.sq.analysis-to{box-shadow:inset 0 0 0 5px rgba(196,119,16,.65)}
@media(max-width:700px){.famous-study-head{align-items:flex-start;flex-direction:column}.famous-study-head>span{text-align:left}.famous-study-actions button{flex:1 1 42%}.analysis-list{max-height:420px}}

/* V24 dedicated Famous Game Player */
body.fg-modal-open{overflow:hidden}.fg-modal[hidden]{display:none!important}.fg-modal{position:fixed;inset:0;z-index:10050;background:rgba(12,22,35,.78);display:flex;align-items:center;justify-content:center;padding:18px}.fg-dialog{width:min(1180px,98vw);height:min(850px,96vh);background:#f8fbff;border-radius:18px;box-shadow:0 25px 80px rgba(0,0,0,.4);display:flex;flex-direction:column;overflow:hidden}.fg-topbar{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:13px 16px;background:#eaf1f8;border-bottom:1px solid #cbd8e7}.fg-topbar>div{min-width:0}.fg-topbar strong{display:block;font-size:18px;color:#0e365d;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.fg-topbar small{display:block;margin-top:3px;color:#52697f;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.fg-close{border:0!important;background:#fff!important;color:#203b55!important;border-radius:10px!important;font-size:20px!important;line-height:1!important;width:40px;height:40px;flex:0 0 auto}.fg-body{display:grid;grid-template-columns:minmax(360px,560px) minmax(360px,1fr);gap:18px;padding:16px;overflow:hidden;flex:1}.fg-board-side{display:flex;flex-direction:column;align-items:center;min-width:0}.fg-board{width:min(100%,560px);aspect-ratio:1/1;display:grid;grid-template-columns:repeat(8,1fr);border:3px solid #244664;border-radius:8px;overflow:hidden;box-shadow:0 8px 24px rgba(22,54,82,.2)}.fg-sq{position:relative;display:flex;align-items:center;justify-content:center}.fg-sq.light{background:#eef1d8}.fg-sq.dark{background:#6f8f73}.fg-sq img{width:88%;height:88%;object-fit:contain;user-select:none;pointer-events:none}.fg-sq.fg-last-from:after,.fg-sq.fg-last-to:after{content:"";position:absolute;inset:7%;border:3px solid rgba(235,158,23,.78);border-radius:8px;pointer-events:none}.fg-sq.fg-best-from:before,.fg-sq.fg-best-to:before{content:"";position:absolute;inset:12%;border:4px solid rgba(16,118,91,.9);border-radius:50%;pointer-events:none}.fg-file,.fg-rank{position:absolute;font-size:10px;font-weight:800;opacity:.7}.fg-file{right:3px;bottom:1px}.fg-rank{left:3px;top:1px}.fg-status{margin-top:10px;width:min(100%,560px);padding:9px 12px;background:#edf5fb;border:1px solid #ceddea;border-radius:10px;color:#32536d;text-align:center;font-weight:700}.fg-study-side{display:flex;flex-direction:column;min-width:0;overflow:hidden}.fg-controls,.fg-options{display:flex;flex-wrap:wrap;gap:8px}.fg-controls button,.fg-options button,.fg-options select{border:1px solid #c8d6e5;background:#fff;color:#153b5e;border-radius:9px;padding:9px 11px;font-weight:700}.fg-controls .fg-primary{background:#124c79;color:#fff;border-color:#124c79}.fg-options{margin-top:9px}.fg-options label{display:flex;align-items:center;gap:6px;font-size:13px;color:#456078}.fg-options .fg-analyze{background:#087555;color:#fff;border-color:#087555}.fg-controls button:disabled,.fg-options button:disabled{opacity:.45}.fg-moves{margin-top:12px;border:1px solid #d3deea;border-radius:10px;background:#fff;overflow:auto;min-height:180px;flex:1;padding:7px}.fg-move-row{display:grid;grid-template-columns:44px 1fr 1fr;gap:4px;align-items:center}.fg-num{padding:7px;color:#6b7c8d;font-weight:700;text-align:right}.fg-move-row button{border:0;background:transparent;border-radius:6px;padding:7px 8px;text-align:left;font:inherit;cursor:pointer}.fg-move-row button:hover{background:#edf4fa}.fg-move-row button.active{background:#cce4f7;color:#0e426a;font-weight:800}.fg-analysis{margin-top:10px;border:1px solid #cddce9;border-radius:10px;background:#fff;max-height:300px;overflow:auto;padding:10px}.fg-analysis-progress,.fg-analysis-head{display:flex;justify-content:space-between;gap:12px;color:#31516b}.fg-analysis-badges{display:flex;flex-wrap:wrap;gap:5px;margin:8px 0}.fg-analysis-badges span{background:#edf3f8;border-radius:999px;padding:4px 8px;font-size:12px}.fg-review-list{display:grid;gap:6px}.fg-review-list button{display:grid;grid-template-columns:auto auto;gap:2px 10px;text-align:left;border:1px solid #d8e2ec;background:#fbfdff;border-radius:8px;padding:8px}.fg-review-list button span{grid-column:1/-1;font-size:12px;color:#557086}.fg-review-list em{font-style:normal;font-size:11px;font-weight:800;color:#8b4c19}.fg-analysis-note{font-size:11px;color:#6f7f8e}.fg-loading,.fg-error{padding:16px;color:#566e82}.fg-error{color:#9a332a}
@media(max-width:850px){.fg-modal{padding:6px}.fg-dialog{height:98vh;width:99vw;border-radius:10px}.fg-body{grid-template-columns:1fr;overflow:auto;padding:9px}.fg-board{width:min(92vw,520px)}.fg-study-side{overflow:visible}.fg-moves{max-height:330px;min-height:220px;flex:none}.fg-analysis{max-height:360px}.fg-topbar strong{font-size:15px}}

/* V25 Famous Game Player: strict equal squares + richer analysis */
.fg-board{grid-template-columns:repeat(8,minmax(0,1fr))!important;grid-template-rows:repeat(8,minmax(0,1fr))!important;align-items:stretch!important;justify-items:stretch!important;box-sizing:border-box!important}
.fg-sq{min-width:0!important;min-height:0!important;width:100%!important;height:100%!important;overflow:hidden!important;box-sizing:border-box!important}
.fg-sq img{display:block!important;max-width:92%!important;max-height:92%!important;width:88%!important;height:88%!important}
.fg-analysis-head>div{display:flex;flex-direction:column;gap:2px}.fg-analysis-head small{font-size:11px;color:#6b8092;font-weight:600}.fg-analysis-filters{display:flex;gap:6px;margin:8px 0}.fg-analysis-filters button{border:1px solid #ccd9e5;background:#fff;border-radius:7px;padding:5px 8px;font-size:11px;font-weight:800;color:#34546d}.fg-analysis-filters button.active{background:#174f78;color:#fff;border-color:#174f78}.fg-review-list button{display:block!important;width:100%;text-align:left}.fg-review-top{display:flex;justify-content:space-between;gap:10px;align-items:center}.fg-review-list button>span,.fg-review-list button>small{display:block!important;margin-top:5px;line-height:1.4}.fg-review-list button>small{color:#465f73}.fg-review-list .fg-remember{background:#f2f7fb;border-left:3px solid #3f789f;padding:6px 7px;border-radius:4px}.fg-review-list em{padding:2px 6px;border-radius:999px;background:#f4ede5}.fg-review-list em.grade-Blunder{background:#fde7e4;color:#9b2d24}.fg-review-list em.grade-Mistake{background:#fff0d9;color:#935b00}.fg-review-list em.grade-Missed-Chance{background:#efe9ff;color:#6541a5}.fg-review-list em.grade-Inaccuracy{background:#fff7cf;color:#7b6800}.fg-review-list em.grade-Best,.fg-review-list em.grade-Excellent{background:#e4f5ea;color:#257140}