:root {
  --bg0:#0b1220; --bg1:#111827; --panel:rgba(15,23,42,.82); --line:rgba(148,163,184,.18);
  --text:#f8fafc; --muted:#94a3b8; --accent:#38bdf8; --good:#34d399; --bad:#fb7185; --warn:#fbbf24;
  --board:#e2e8f0; --given:#020617; --user:#0c4a6e; --note:#475569; --same:rgba(56,189,248,.18);
  --hl:rgba(56,189,248,.12); --err:rgba(251,113,133,.22); --radius:16px; --shadow:0 18px 50px rgba(0,0,0,.35);
  --cell: min(9.2vw, 52px);
}
*{box-sizing:border-box} html,body{margin:0;min-height:100%;color:var(--text);font-family:Inter,system-ui,sans-serif;
background:radial-gradient(circle at 15% 15%,rgba(56,189,248,.12),transparent 28%),radial-gradient(circle at 85% 10%,rgba(52,211,153,.1),transparent 24%),linear-gradient(165deg,#0b1220,#111827 50%,#0f172a)}
body.sudoku-remake{overflow-x:hidden}
.app{min-height:100vh;display:flex;flex-direction:column}
.top{display:flex;justify-content:space-between;gap:10px;align-items:center;padding:12px 16px;border-bottom:1px solid var(--line);background:rgba(15,23,42,.75);backdrop-filter:blur(12px);position:sticky;top:0;z-index:10}
.brand{display:flex;gap:10px;align-items:center;font-weight:800}
.badge{width:36px;height:36px;border-radius:12px;display:grid;place-items:center;background:linear-gradient(135deg,#38bdf8,#34d399);color:#052e16}
.brand small{display:block;color:var(--muted);font-size:12px;font-weight:600}
.row{display:flex;gap:8px;flex-wrap:wrap;align-items:center}
.btn,.select{appearance:none;border:1px solid var(--line);background:rgba(255,255,255,.04);color:var(--text);border-radius:12px;min-height:40px;padding:8px 12px;font-weight:700;cursor:pointer}
.btn.primary{background:linear-gradient(135deg,#38bdf8,#0ea5e9);color:#082f49;border:none}
.btn.active{border-color:rgba(56,189,248,.55);background:rgba(56,189,248,.14)}
.btn:disabled{opacity:.45;cursor:not-allowed}
.btn:focus-visible,.select:focus-visible,.num:focus-visible,.cell:focus-visible{outline:2px solid #38bdf8;outline-offset:2px}
.main{width:min(1100px,100%);margin:0 auto;padding:16px;display:grid;gap:14px}
.stats{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:10px}
.card{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:12px}
.card span{display:block;color:var(--muted);font-size:12px;margin-bottom:4px}
.card strong{font-size:20px}
.layout{display:grid;grid-template-columns:minmax(0,1fr) 280px;gap:14px;align-items:start}
.board-wrap{display:flex;flex-direction:column;align-items:center;gap:12px}
.board{
  width:calc(var(--cell)*9); display:grid; grid-template-columns:repeat(9,var(--cell)); grid-template-rows:repeat(9,var(--cell));
  background:var(--board); border-radius:18px; overflow:hidden; box-shadow:var(--shadow); border:3px solid #94a3b8;
}
.cell{position:relative;display:grid;place-items:center;background:#f8fafc;color:var(--user);font-weight:900;font-size:calc(var(--cell)*.48);line-height:1;border:1px solid #cbd5e1;cursor:pointer;user-select:none;margin:0;padding:0;font-family:ui-sans-serif,system-ui,sans-serif;border-radius:0;min-width:0;min-height:0}
.cell:nth-child(9n+3),.cell:nth-child(9n+6){border-right:2px solid #64748b}
.cell:nth-child(n+19):nth-child(-n+27),.cell:nth-child(n+46):nth-child(-n+54){border-bottom:2px solid #64748b}
.cell.given{color:var(--given)}
.cell .digit{display:block;color:inherit;font:inherit;font-weight:900;line-height:1;letter-spacing:-0.02em;-webkit-text-fill-color:currentColor;text-shadow:0 1px 0 rgba(255,255,255,.35)}
.cell.selected{outline:2px solid #0ea5e9;outline-offset:-2px;z-index:2}
.cell.hl{background:#e0f2fe}
.cell.same{background:var(--same)}
.cell.error{background:var(--err);color:#be123c}
.cell.hint{box-shadow:inset 0 0 0 2px #f59e0b}
.cell.related-number{background:#dbeafe}
.notes{position:absolute;inset:2px;display:grid;grid-template-columns:repeat(3,1fr);grid-template-rows:repeat(3,1fr);font-size:calc(var(--cell)*.18);color:var(--note);font-weight:700;line-height:1}
.notes i{display:grid;place-items:center;font-style:normal}
.dock{width:calc(var(--cell)*9);display:grid;grid-template-columns:repeat(9,minmax(0,1fr));gap:8px}
.num{min-height:48px;border-radius:12px;border:1px solid var(--line);background:rgba(255,255,255,.05);color:var(--text);font-weight:800;font-size:18px;cursor:pointer}
.num small{display:block;font-size:10px;color:var(--muted);font-weight:700}
.tools{width:calc(var(--cell)*9);display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:8px}
.status{width:calc(var(--cell)*9);color:var(--muted);min-height:20px;font-size:14px}
.side{display:grid;gap:12px}
.side h3{margin:0 0 8px;font-size:15px}
.side p,.side li{color:var(--muted);font-size:13px;line-height:1.5}
.side ul{margin:0;padding-left:18px}
.ach{display:grid;gap:8px}
.ach-item{display:flex;gap:8px;padding:8px;border-radius:12px;border:1px solid var(--line);background:rgba(255,255,255,.03);color:var(--muted);font-size:12px}
.ach-item.on{color:var(--text);border-color:rgba(251,191,36,.35);background:rgba(251,191,36,.08)}
.overlay{position:fixed;inset:0;background:rgba(2,6,23,.62);display:none;place-items:center;z-index:30;padding:16px}
.overlay.show{display:grid}
.modal{width:min(420px,100%);background:rgba(15,23,42,.96);border:1px solid var(--line);border-radius:18px;box-shadow:var(--shadow);padding:18px}
.modal h2{margin:0 0 8px}.modal p{color:var(--muted)}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:8px;margin:12px 0}
.grid2 div{background:rgba(255,255,255,.04);border-radius:12px;padding:10px}
.grid2 span{display:block;color:var(--muted);font-size:12px}
.toast{position:fixed;left:50%;bottom:16px;transform:translateX(-50%) translateY(16px);background:rgba(15,23,42,.95);border:1px solid rgba(56,189,248,.35);padding:10px 14px;border-radius:999px;opacity:0;transition:.2s;z-index:40;font-weight:700}
.toast.show{opacity:1;transform:translateX(-50%) translateY(0)}
@media(max-width:920px){.layout{grid-template-columns:1fr}.stats{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:640px){
  :root{--cell:min(10.2vw,44px)}
  .top{padding:10px}
  .brand small{display:none}
  .tools{grid-template-columns:repeat(2,minmax(0,1fr))}
  .num{min-height:44px}
}
@media (prefers-reduced-motion: reduce){
  .toast{transition:none}
}