:root{--bg-color: #1a1a2e;--text-color: #e94560;--board-bg: #16213e;--square-bg: #0f3460;--square-hover: #1f4287;--x-color: #4cc9f0;--o-color: #f72585;--win-color: #4ade80;--font-main: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;--toggle-bg: #ccc;--toggle-knob: #fff}[data-theme=light]{--bg-color: #f0f2f5;--text-color: #e94560;--board-bg: #ffffff;--square-bg: #e0e0e0;--square-hover: #d0d0d0;--x-color: #0077b6;--o-color: #d00000;--win-color: #2a9d8f;--toggle-bg: #2196F3;--toggle-knob: #fff}body{margin:0;font-family:var(--font-main);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background-color:var(--bg-color);color:#fff;display:flex;justify-content:center;align-items:center;min-height:100vh}@media(max-width:500px){body{align-items:flex-start;padding-top:0}}#root{width:100%;display:flex;justify-content:center}.game{display:flex;flex-direction:column;align-items:center;gap:2rem;padding:2rem;position:relative}.game-info{text-align:center}h1{font-size:2.5rem;margin-bottom:.5rem;margin-top:0;background:linear-gradient(to right,var(--x-color),var(--o-color));-webkit-background-clip:text;-webkit-text-fill-color:transparent}.status{font-size:1.5rem;margin-bottom:1rem;min-height:2rem}.winner-text{color:var(--win-color);font-weight:700;animation:pop .5s ease}.reset-btn{padding:10px 20px;font-size:1rem;background:var(--text-color);border:none;border-radius:8px;color:#fff;cursor:pointer;transition:transform .2s,background .2s}[data-theme=light] .reset-btn{color:#fff}.mode-btn{padding:8px 16px;font-size:.9rem;background:transparent;border:1px solid var(--x-color);border-radius:6px;color:var(--x-color);cursor:pointer;margin-bottom:1rem;transition:all .3s}.mode-btn:hover{background:#4cc9f01a;box-shadow:0 0 10px #4cc9f066}.reset-btn:hover{transform:scale(1.05);background:#c73e52}.board{display:grid;grid-template-columns:repeat(10,40px);grid-template-rows:repeat(10,40px);gap:4px;padding:10px;background:#ffffff0d;border-radius:12px;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);box-shadow:0 8px 32px #0000005e}.square{background:var(--square-bg);border:none;border-radius:4px;font-size:24px;font-weight:700;cursor:pointer;color:#fff;display:flex;justify-content:center;align-items:center;transition:background .3s,transform .2s;padding:0}.square:hover{background:var(--square-hover)}.square.filled[data-value=X]{color:var(--x-color);text-shadow:0 0 5px var(--x-color)}.square.filled[data-value=O]{color:var(--o-color);text-shadow:0 0 5px var(--o-color)}.square.winning{background:var(--win-color)!important;color:#000!important;transform:scale(1.1);z-index:10;box-shadow:0 0 15px var(--win-color)}@keyframes pop{0%{transform:scale(.8);opacity:0}to{transform:scale(1);opacity:1}}.side-selection{display:flex;gap:1rem;align-items:center;margin-bottom:1rem;font-size:1.1rem;color:var(--text-color)}.side-selection label{display:flex;align-items:center;gap:.3rem;cursor:pointer}.side-selection input[type=radio]{accent-color:var(--x-color);cursor:pointer}.theme-toggle{position:fixed;top:1.5rem;right:1.5rem;padding:8px 16px;border-radius:30px;border:none;background:var(--toggle-bg);color:var(--toggle-knob);font-weight:700;cursor:pointer;box-shadow:0 4px 6px #0000001a;transition:all .3s cubic-bezier(.25,.8,.25,1);z-index:1000;font-size:.9rem;display:flex;align-items:center;gap:.5rem}.theme-toggle:hover{transform:translateY(-2px);box-shadow:0 6px 12px #0003;filter:brightness(1.1)}@media(max-width:500px){.game{gap:1rem;padding:1rem;width:100%}h1{font-size:1.8rem;margin-top:3rem}.theme-toggle{top:1rem;right:1rem;padding:6px 12px;font-size:.8rem}.board{grid-template-columns:repeat(10,30px);grid-template-rows:repeat(10,30px);gap:2px}.square{font-size:18px}.game-info{width:100%}}