@import"https://fonts.googleapis.com/css2?family=Nunito:wght@400;600;700;800;900&display=swap";:root{--bg: #0F172A;--surface: #1E293B;--grid-line: #334155;--cell-bg: #F1F5F9;--cell-hover: #E2F4F8;--cell-winner: #CCFBF1;--x-color: #14B8A6;--o-color: #F97316;--text: #F8FAFC;--text-muted: #94A3B8;--accent: #14B8A6;--accent-dark: #0D9488;--danger: #F43F5E;--board-max: 420px;--cell-radius: 12px;--gap: 10px;--btn-radius: 14px}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html,body{height:100%}body{font-family:Nunito,system-ui,sans-serif;background:var(--bg);color:var(--text);min-height:100vh;display:flex;align-items:stretch}#app{flex:1;display:flex;flex-direction:column;position:relative;overflow:hidden}.screen{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:24px 16px;position:relative;min-height:100vh}.screen.hidden{display:none}.btn-fs{position:absolute;top:16px;right:16px;background:#ffffff0f;border:1.5px solid rgba(255,255,255,.12);border-radius:8px;color:var(--text-muted);width:36px;height:36px;display:flex;align-items:center;justify-content:center;cursor:pointer;transition:color .15s,background .15s;padding:0}.btn-fs:hover{color:var(--text);background:#ffffff1f}.btn-fs .icon-compress,.btn-fs.is-fullscreen .icon-expand{display:none}.btn-fs.is-fullscreen .icon-compress{display:block}.btn-back{position:absolute;top:16px;left:16px;display:flex;align-items:center;gap:4px;background:transparent;border:none;color:var(--text-muted);font-family:inherit;font-size:.9rem;font-weight:700;cursor:pointer;padding:6px 8px;border-radius:8px;transition:color .15s,background .15s}.btn-back:hover{color:var(--text);background:#ffffff0f}:focus-visible{outline:3px solid var(--accent);outline-offset:2px}.start-content{display:flex;flex-direction:column;align-items:center;gap:48px}.game-title{font-size:clamp(2rem,6vw,3.2rem);font-weight:900;text-align:center;line-height:1.2;letter-spacing:-.5px;display:flex;align-items:center;gap:16px;flex-wrap:wrap;justify-content:center}.title-x{font-size:1.1em;color:var(--x-color);text-shadow:0 0 28px rgba(20,184,166,.6)}.title-o{font-size:1.1em;color:var(--o-color);text-shadow:0 0 28px rgba(249,115,22,.6)}.diff-content{display:flex;flex-direction:column;align-items:center;gap:32px;text-align:center}.diff-content h2{font-size:clamp(1.4rem,4vw,2rem);font-weight:900}.diff-subtitle{color:var(--text-muted);font-size:1rem;font-weight:600;margin-top:-20px}.menu-stack{display:flex;flex-direction:column;gap:14px;width:100%;max-width:320px}.btn-primary{background:var(--accent);color:#fff;border:none;border-radius:var(--btn-radius);font-family:inherit;font-size:1rem;font-weight:800;padding:14px 24px;cursor:pointer;box-shadow:0 4px 16px #14b8a64d;transition:transform .1s,box-shadow .1s,background .15s;letter-spacing:.01em}.btn-primary:hover{background:var(--accent-dark);transform:translateY(-2px);box-shadow:0 6px 20px #14b8a666}.btn-primary:active{transform:translateY(0) scale(.98);box-shadow:0 2px 8px #14b8a633}.btn-primary.selected{background:var(--accent-dark);box-shadow:0 0 0 3px var(--accent),0 4px 16px #14b8a64d}.btn-large{font-size:1.1rem;padding:16px 28px}.btn-diff{display:flex;flex-direction:column;align-items:center;gap:4px}.btn-diff .diff-hint{font-size:.78rem;font-weight:600;opacity:.75}.btn-secondary{background:transparent;border:2px solid rgba(255,255,255,.15);border-radius:var(--btn-radius);color:var(--text-muted);font-family:inherit;font-size:.95rem;font-weight:700;padding:12px 24px;cursor:pointer;transition:border-color .15s,color .15s}.btn-secondary:hover{border-color:#ffffff4d;color:var(--text)}.game-header{width:100%;max-width:480px;display:flex;align-items:center;justify-content:space-between;padding:12px 16px;background:var(--surface);border-radius:14px;margin-bottom:8px;flex-shrink:0}.game-header .btn-back,.game-header .btn-fs{position:static;flex-shrink:0}.score-display{display:flex;align-items:center;gap:12px;font-size:1rem;font-weight:800}.score-item{display:flex;align-items:center;gap:8px;padding:4px 10px;border-radius:8px;transition:background .2s}.score-item.active{background:#ffffff14}.score-num{font-size:1.3rem;font-weight:900;min-width:1.5ch;text-align:center}.score-sep{color:var(--text-muted);font-size:1.1rem}.mark-x{color:var(--x-color);font-weight:900}.mark-o{color:var(--o-color);font-weight:900}.status-bar{font-size:.95rem;font-weight:700;color:var(--text-muted);text-align:center;min-height:1.5em;padding:4px 0 8px;flex-shrink:0}#screen-game{justify-content:flex-start;padding-top:20px}.board-wrapper{flex:1;display:flex;align-items:center;justify-content:center;padding:8px 16px 24px;width:100%}.board{--board-size: min(min(92vw, 70vh), var(--board-max));width:var(--board-size);display:grid;grid-template-columns:repeat(3,1fr);grid-template-rows:repeat(3,1fr);gap:var(--gap);background:var(--grid-line);border-radius:18px;padding:var(--gap);aspect-ratio:1}.cell{background:var(--cell-bg);border:none;border-radius:var(--cell-radius);cursor:pointer;display:flex;align-items:center;justify-content:center;font-family:inherit;font-size:clamp(2rem,10vmin,4.2rem);font-weight:900;transition:background .12s,transform .08s;-webkit-tap-highlight-color:transparent;-webkit-user-select:none;user-select:none}.cell:not(.filled):not(:disabled):hover{background:var(--cell-hover);transform:scale(.97)}.cell:not(.filled):not(:disabled):active{transform:scale(.93)}.cell.filled{cursor:default}.cell.winner{background:var(--cell-winner)}.mark{display:block;line-height:1;animation:pop-in .22s cubic-bezier(.175,.885,.32,1.275) both}.mark.mark-x{color:var(--x-color);text-shadow:0 0 20px rgba(20,184,166,.45)}.mark.mark-o{color:var(--o-color);text-shadow:0 0 20px rgba(249,115,22,.45)}.cell.winner .mark.mark-x{text-shadow:0 0 28px rgba(20,184,166,.8)}.cell.winner .mark.mark-o{text-shadow:0 0 28px rgba(249,115,22,.8)}@keyframes pop-in{0%{transform:scale(.2) rotate(-12deg);opacity:0}70%{transform:scale(1.18) rotate(4deg)}to{transform:scale(1) rotate(0);opacity:1}}.overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#000000a6;-webkit-backdrop-filter:blur(6px);backdrop-filter:blur(6px);display:flex;align-items:center;justify-content:center;padding:24px;z-index:100;opacity:1;transition:opacity .25s ease}.overlay.hidden{opacity:0;pointer-events:none;visibility:hidden}.overlay-card{background:var(--surface);border-radius:24px;padding:40px 32px;text-align:center;max-width:360px;width:100%;box-shadow:0 20px 60px #00000080,0 1px #ffffff0f inset;display:flex;flex-direction:column;gap:28px;animation:card-pop .35s cubic-bezier(.34,1.56,.64,1) both}@keyframes card-pop{0%{transform:scale(.8);opacity:0}to{transform:scale(1);opacity:1}}.overlay-title{font-size:clamp(1.6rem,5vw,2.2rem);font-weight:900;line-height:1.2}.overlay-actions{display:flex;flex-direction:column;gap:12px}@media (max-height: 600px){.game-header{padding:8px 12px}.status-bar{padding:2px 0 4px;font-size:.85rem}#screen-game{padding-top:10px}:root{--board-max: 320px}}@media (min-width: 640px){:root{--board-max: 480px}}:fullscreen #app,:-webkit-full-screen #app{background:var(--bg)}:fullscreen .screen,:-webkit-full-screen .screen{min-height:100vh}:fullscreen .board-wrapper,:-webkit-full-screen .board-wrapper{flex:1}