:root{color-scheme:light;--ink:#172033;--muted:#5a6375;--paper:#f7f4ef;--card:#fff;--line:#e4ddd1;--orange:#f26b2b;--orange-d:#d85a1e;--light:#efe4d2;--dark:#b88a62;--ok:#1f8a46;--bad:#c0281f;--shadow:0 12px 40px rgba(23,32,51,.12);--board:min(92vw,500px,calc(100vh - 250px));--sans:"Segoe UI",Helvetica,Arial,sans-serif}
*{box-sizing:border-box}
html,body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--sans);-webkit-tap-highlight-color:transparent}
button{font:inherit;color:inherit;cursor:pointer}
[hidden]{display:none!important}
.top{display:flex;justify-content:space-between;align-items:center;padding:10px 16px;max-width:640px;margin:0 auto}
.back{color:var(--muted);text-decoration:none;font-size:.9rem}
.icon{background:none;border:0;font-size:1.4rem;line-height:1;padding:6px 8px;border-radius:8px}
.icon:hover{background:rgba(23,32,51,.06)}
main{max-width:640px;margin:0 auto;padding:0 16px 40px}
h1{font-family:Georgia,"Times New Roman",serif;font-style:italic;font-size:2.2rem;margin:.4em 0 .1em;text-align:center}
.lede{text-align:center;color:var(--muted);margin:0 0 1.4em}
.seg{display:flex;background:#ebe5da;border-radius:12px;padding:4px;gap:4px;margin:0 auto 18px;max-width:440px}
.seg button{flex:1;border:0;background:none;padding:10px 8px;border-radius:9px;font-weight:600;display:flex;flex-direction:column;align-items:center;gap:2px}
.seg button small{font-weight:400;font-size:.75rem;color:var(--muted)}
.seg button.on{background:#fff;box-shadow:0 1px 4px rgba(0,0,0,.08)}
.seg.sm{max-width:260px;margin:0 0 12px}.seg.sm button{padding:6px}
.big{display:block;width:100%;max-width:440px;margin:0 auto 14px;border:0;border-radius:16px;padding:20px 18px 16px;font-size:1.15rem;font-weight:700;text-align:left;box-shadow:var(--shadow);transition:transform .1s}
.big:active{transform:scale(.98)}
.big.w{background:#fff;color:var(--ink)}
.big.b{background:var(--ink);color:#fff}
.big .sub{display:block;font-weight:400;font-size:.85rem;opacity:.75;margin-top:4px}
.bar{display:block;height:6px;border-radius:3px;background:rgba(127,127,127,.22);margin-top:10px;overflow:hidden}
.bar i{display:block;height:100%;width:0;background:var(--orange);transition:width .4s}
.quick{display:flex;justify-content:center;gap:6px;flex-wrap:wrap;margin-top:22px}
.quick button,.link{background:none;border:0;color:var(--muted);text-decoration:underline;text-underline-offset:3px;padding:6px 8px;font-size:.9rem}
.link{padding:0;color:var(--orange-d)}
.small{font-size:.85rem}.muted{color:var(--muted)}.center{text-align:center}
#emptyNote{text-align:center}
/* trainer */
.tbar{display:flex;align-items:center;justify-content:space-between;gap:8px;margin:0 auto 10px;max-width:var(--board)}
.ttl{font-weight:700;font-size:.95rem;text-align:center;flex:1}
.pill{border:1px solid var(--line);background:#fff;border-radius:999px;padding:6px 12px;font-size:.85rem}
.boardwrap{position:relative;width:var(--board);height:var(--board);margin:0 auto}
.board{position:absolute;inset:0;display:grid;grid-template:repeat(8,1fr)/repeat(8,1fr);border-radius:calc(var(--board)/60);overflow:hidden;box-shadow:var(--shadow);touch-action:none;user-select:none;-webkit-user-select:none}
.board.shake{animation:shake .26s ease}
@keyframes shake{25%{transform:translateX(-6px)}75%{transform:translateX(6px)}}
.sq{position:relative}
.sq.l{background:var(--light)}.sq.d{background:var(--dark)}
.sq.last::before,.sq.sel::before{content:"";position:absolute;inset:0;background:rgba(242,107,43,.28)}
.sq.sel::before{background:rgba(242,107,43,.45)}
.sq.dot::after{content:"";position:absolute;left:50%;top:50%;width:28%;height:28%;transform:translate(-50%,-50%);border-radius:50%;background:rgba(23,32,51,.22)}
.sq.incheck{background:radial-gradient(circle,rgba(230,35,35,.9) 0%,rgba(230,35,35,.4) 45%,transparent 75%)}
.sq img{position:absolute;inset:0;width:100%;height:100%;pointer-events:none;filter:drop-shadow(0 2px 1.5px rgba(0,0,0,.25));z-index:1}
.coord{position:absolute;font-weight:700;font-size:clamp(9px,calc(var(--board)/44),14px);line-height:1;pointer-events:none}
.sq.l .coord{color:var(--dark)}.sq.d .coord{color:var(--light)}
.coord.r{top:5%;left:6%}.coord.f{bottom:5%;right:7%}
.drag{position:fixed;pointer-events:none;z-index:50;width:calc(var(--board)/8);height:calc(var(--board)/8);transform:translate(-50%,-50%)}
.arrows{position:absolute;inset:0;width:100%;height:100%;pointer-events:none;z-index:3}
.arrows line{stroke-width:.17;stroke-linecap:round;opacity:.85}
.arrows .a-go{stroke:var(--orange)}.arrows .a-hint{stroke:#2f6fd6}
.status{min-height:2.6em;text-align:center;margin:12px auto 4px;font-weight:600;max-width:var(--board);display:flex;align-items:center;justify-content:center}
.status.ok{color:var(--ok)}.status.bad{color:var(--bad)}
.moves{text-align:center;color:var(--muted);font-size:.85rem;min-height:1.3em;max-width:var(--board);margin:0 auto 10px;line-height:1.5}
.moves b{color:var(--ink)}
.actions{display:flex;flex-wrap:wrap;justify-content:center;gap:8px;margin:0 auto 12px;max-width:var(--board)}
.btn{border:1px solid var(--line);background:#fff;border-radius:10px;padding:10px 16px;font-weight:600;font-size:.95rem;display:inline-flex;align-items:center;justify-content:center}
.btn.primary{background:var(--orange);border-color:var(--orange);color:#fff}
.btn.primary:hover{background:var(--orange-d)}
.btn.ghost{background:none;border-color:transparent;color:var(--muted)}
.btn.ghost:hover{background:rgba(23,32,51,.05)}
.btn.danger{background:none;color:var(--bad);border-color:transparent;font-weight:500;margin-top:8px}
.tog{display:flex;gap:8px;align-items:center;justify-content:center;font-size:.9rem;color:var(--muted);margin:6px 0}
.panel .tog{justify-content:flex-start}
/* sheet */
.sheet{position:fixed;inset:0;background:rgba(23,32,51,.35);z-index:40;display:flex;align-items:flex-end;justify-content:center}
.sheet-in{background:var(--paper);width:100%;max-width:640px;max-height:86vh;overflow:auto;border-radius:18px 18px 0 0;padding:6px 18px calc(22px + env(safe-area-inset-bottom));box-shadow:0 -10px 40px rgba(0,0,0,.15);animation:up .2s ease}
@keyframes up{from{transform:translateY(30px);opacity:.5}}
@media(min-width:700px){.sheet{align-items:center}.sheet-in{border-radius:18px;max-height:80vh}}
.sheet-h{display:flex;justify-content:space-between;align-items:center;position:sticky;top:0;background:var(--paper);padding:10px 0;z-index:2}
.sheet-h b{font-size:1.1rem}
.panel{display:none}.panel.on{display:block}
.row{display:block;width:100%;text-align:left;background:#fff;border:0;border-bottom:1px solid var(--line);padding:14px 12px;font-size:1rem}
.row:first-child{border-radius:12px 12px 0 0}.row:last-child{border-radius:0 0 12px 12px;border:0}
.lbl{display:block;font-size:.8rem;font-weight:700;text-transform:uppercase;letter-spacing:.04em;color:var(--muted);margin:14px 0 6px}
textarea,input[type=password],input[type=text]{width:100%;border:1px solid var(--line);border-radius:10px;padding:10px;font:inherit;font-size:.95rem;background:#fff}
textarea{font-family:ui-monospace,Menlo,monospace;font-size:.85rem}
input[type=range]{width:100%}
.panel .btn.primary{margin-top:10px;width:100%}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:8px}
.msg{font-size:.9rem;margin-top:8px;min-height:1em}
.msg.ok{color:var(--ok)}.msg.bad{color:var(--bad)}
.note{font-size:.82rem;color:var(--muted);background:#efe9df;border-radius:10px;padding:10px 12px;margin-top:14px}
/* tree */
.tree{font-size:.95rem}
.tree ul{list-style:none;margin:0;padding-left:14px;border-left:2px solid var(--line)}
.tree>ul{padding-left:0;border:0}
.tree li{margin:2px 0}
.tn{display:inline-flex;align-items:center;gap:6px}
.tn .mv{border:0;background:#fff;border-radius:8px;padding:4px 9px;font-weight:600;box-shadow:0 1px 2px rgba(0,0,0,.06)}
.tn .mv.mine{background:var(--ink);color:#fff}
.tn .mv.open{outline:2px solid var(--orange)}
.tn .cnt{font-size:.75rem;color:var(--muted)}
.tn .go{border:0;background:none;color:var(--orange-d);font-size:.8rem;padding:2px 4px}
.tn .pct{font-size:.72rem;color:var(--muted)}
.miss{display:flex;justify-content:space-between;align-items:center;gap:10px;background:#fff;border-radius:10px;padding:10px 12px;margin-bottom:8px}
.miss .seq{font-size:.85rem;color:var(--muted)}.miss .seq b{color:var(--ink)}
.miss .n{color:var(--bad);font-weight:700;white-space:nowrap}
.toast{position:fixed;left:50%;bottom:24px;transform:translateX(-50%);background:var(--ink);color:#fff;padding:10px 16px;border-radius:10px;z-index:60;font-size:.9rem;box-shadow:var(--shadow)}
.endcard{background:#fff;border-radius:14px;padding:12px;margin:0 auto 12px;max-width:var(--board);text-align:center;box-shadow:0 1px 4px rgba(0,0,0,.06)}

.shot{background:#fff;border-radius:12px;padding:10px;margin-top:10px}
.shot-h{display:flex;gap:8px;align-items:baseline;flex-wrap:wrap;margin-bottom:8px}.shot-h b{font-size:.9rem;word-break:break-all}.shot-h .link{margin-left:auto}
.shot-b{display:flex;gap:10px;align-items:flex-start}
.mini{flex:0 0 120px;height:120px;display:grid;grid-template:repeat(8,1fr)/repeat(8,1fr);border-radius:4px;overflow:hidden}
.mini i{position:relative}.mini i.l{background:var(--light)}.mini i.d{background:var(--dark)}.mini img{position:absolute;inset:0;width:100%;height:100%}
.toks{display:flex;flex-wrap:wrap;gap:4px;align-items:center}
.tok{display:inline-flex;border:1px solid var(--line);border-radius:6px;overflow:hidden;background:#fff}
.tok input{border:0;padding:3px 4px;font:600 .85rem ui-monospace,Menlo,monospace;width:auto;min-width:2.5em;background:transparent}
.tok button{border:0;background:none;color:var(--muted);padding:0 5px}
.tok.ok{border-color:#b9dcc5}.tok.bad{border-color:var(--bad);background:#fde8e6}.tok.bad input{color:var(--bad)}
.tok.unclear{border-style:dashed}.tok.skip{opacity:.55}

/* header + theme toggle */
.hdr-r{display:flex;align-items:center;gap:2px}
#themeBtn .moon{display:inline}#themeBtn .sun{display:none}
html[data-theme="dark"] #themeBtn .moon{display:none}html[data-theme="dark"] #themeBtn .sun{display:inline}
/* dark theme (matches Blunderer) */
html[data-theme="dark"]{color-scheme:dark;--ink:#ece6da;--muted:#a9b1bf;--paper:#12161e;--card:#1c2330;--line:#2f3a4c;--light:#8d9aab;--dark:#56637a;--ok:#5fe08f;--bad:#ff7b70;--orange-d:#ff8a4c;--shadow:0 12px 40px rgba(0,0,0,.55);background:#12161e}
html[data-theme="dark"] .icon:hover,html[data-theme="dark"] .btn.ghost:hover{background:rgba(255,255,255,.08)}
html[data-theme="dark"] .seg{background:#0b0e14}
html[data-theme="dark"] .seg button.on{background:#2a3446;box-shadow:0 1px 4px rgba(0,0,0,.4)}
html[data-theme="dark"] .big.w{background:#e9e4da;color:#172033}
html[data-theme="dark"] .big.b{background:#1c2330;color:#ece6da;border:1px solid #2f3a4c}
html[data-theme="dark"] .pill,html[data-theme="dark"] .btn,html[data-theme="dark"] .row,html[data-theme="dark"] .tn .mv,html[data-theme="dark"] .miss,html[data-theme="dark"] .endcard,html[data-theme="dark"] .shot,html[data-theme="dark"] .tok,html[data-theme="dark"] textarea,html[data-theme="dark"] input[type=password],html[data-theme="dark"] input[type=text]{background:var(--card);color:var(--ink)}
html[data-theme="dark"] .btn.primary{background:var(--orange);border-color:var(--orange);color:#fff}
html[data-theme="dark"] .btn.primary:hover{background:#d85a1e}
html[data-theme="dark"] .btn.ghost,html[data-theme="dark"] .btn.danger{background:none}
html[data-theme="dark"] .tn .mv.mine{background:#e9e4da;color:#172033}
html[data-theme="dark"] .toast{background:#e9e4da;color:#172033}
html[data-theme="dark"] .note{background:#1a202b}
html[data-theme="dark"] .sheet{background:rgba(0,0,0,.6)}
html[data-theme="dark"] .sheet-in{box-shadow:0 -10px 40px rgba(0,0,0,.6)}
html[data-theme="dark"] .tok input{color:var(--ink)}
html[data-theme="dark"] .tok.ok{border-color:#2f6b45}
html[data-theme="dark"] .tok.bad{background:#3a1d1c}
html[data-theme="dark"] .sq.l .coord{color:#262e3c}html[data-theme="dark"] .sq.d .coord{color:#e3e8ef}
html[data-theme="dark"] .sq.dot::after{background:rgba(10,14,22,.42)}
html[data-theme="dark"] .arrows .a-hint{stroke:#5aa2ff}
html[data-theme="dark"] .arrows line{opacity:.9}
html[data-theme="dark"] input[type=file]{color:var(--ink)}
html[data-theme="dark"] .sq img[src*="pieces/b"],html[data-theme="dark"] .mini img[src*="pieces/b"]{filter:drop-shadow(0 0 2px rgba(240,235,225,.35)) drop-shadow(0 2px 1.5px rgba(0,0,0,.4))}
/* insights: similar / hot / novelties */
.insights{max-width:var(--board);margin:0 auto 10px;display:flex;flex-direction:column;gap:6px}
.ins{font-size:.85rem;border-radius:10px;padding:8px 10px;background:var(--card,#fff);border:1px solid var(--line);display:flex;flex-wrap:wrap;gap:4px 8px;align-items:center;line-height:1.35}
.ins .peek{color:var(--muted);flex:1 1 100%;font-size:.8rem;word-break:break-word}
.ins .link{font-size:.82rem}
.ins.warn{border-color:#e0a526;background:#fff6dd}
.badge-hot,.badge-nov{display:inline-block;font-size:.66rem;font-weight:800;letter-spacing:.04em;border-radius:5px;padding:1px 5px;color:#fff;background:#d6332a;vertical-align:1px}
.badge-nov{background:#2f6fd6}
.redsq{display:inline-block;width:12px;height:12px;border-radius:3px;background:rgba(220,30,30,.75);margin-right:2px}
.sq.hotsq::before{content:"";position:absolute;inset:0;background:rgba(220,30,30,.42);box-shadow:inset 0 0 0 3px rgba(200,20,20,.85);z-index:0}
.simpair,.novc{background:var(--card,#fff);border:1px solid var(--line);border-radius:12px;padding:10px;margin-bottom:10px}
.simboards{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-bottom:6px}
.simboards .mini{width:100%;height:auto;aspect-ratio:1;flex:none}
.mini i.df::after{content:"";position:absolute;inset:0;background:rgba(242,107,43,.5);box-shadow:inset 0 0 0 2px #f26b2b}
.simboards .seq{margin-top:4px;word-break:break-word}
.simact{display:flex;flex-wrap:wrap;gap:6px;margin-top:8px}.simact .btn{padding:7px 10px;font-size:.85rem}
.novc .novm{margin-bottom:4px;word-break:break-word}.novc .ev{font-family:ui-monospace,Menlo,monospace;font-size:.85rem}
.novc .btn{margin-top:8px;padding:7px 10px;font-size:.85rem}
html[data-theme="dark"] .ins.warn{background:#3a2f12;border-color:#a77d1c}
html[data-theme="dark"] .ins,html[data-theme="dark"] .simpair,html[data-theme="dark"] .novc{background:var(--card)}
html[data-theme="dark"] .badge-hot{background:#e0453b}html[data-theme="dark"] .badge-nov{background:#3d7fe6}
html[data-theme="dark"] .sq.hotsq::before{background:rgba(255,60,50,.45);box-shadow:inset 0 0 0 3px #ff5a4e}
.ins .dismiss,.btn.dismiss{color:var(--muted)}
.ins .dismiss{margin-left:auto;text-decoration:none}
.btn.dismiss{background:none;border-color:var(--line)}
.dismissed{margin-top:8px;font-size:.9rem}.dismissed summary{cursor:pointer;color:var(--muted);padding:6px 0}
.dism-row{display:flex;justify-content:space-between;align-items:center;gap:8px;padding:8px 10px;border:1px solid var(--line);border-radius:10px;margin-bottom:6px;background:var(--card,#fff)}
.dism-row span{word-break:break-word}.dism-row .btn{padding:6px 10px;font-size:.85rem;flex:none}
html[data-theme="dark"] .btn.dismiss{background:none;color:var(--muted)}
/* account */
.pill.acct{max-width:9.5em;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;padding:5px 11px;margin-right:2px;color:var(--ink)}
.pill.acct.on{border-color:var(--orange)}
html[data-theme="dark"] .pill.acct{background:var(--card)}
#authForm input{margin-bottom:10px;font-size:16px}
#authForm .grid2 .btn{width:100%;margin-top:0}
#authGuest{display:block;margin:14px auto 0;font-size:.95rem}
.panel[data-panel=upload] .btn{width:100%}
@media(max-width:420px){.back{font-size:.8rem}.pill.acct{max-width:7em}}

/* Opening trainer: links to the rest of the site */
a.row{color:inherit;text-decoration:none;box-sizing:border-box}
.ot-more{margin-top:18px}.ot-more a{color:inherit;text-decoration:underline}
/* signed out: only the sign-in prompt */
body.gated main,body.gated #menuBtn,body.gated #sheetClose{display:none!important}