:root{font-family:system-ui,Avenir,Helvetica,Arial,sans-serif;line-height:1.5;font-weight:400;color-scheme:light dark;color:#ffffffde;background-color:#242424;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}a{font-weight:500;color:#646cff;text-decoration:inherit}a:hover{color:#535bf2}body{margin:0;display:flex;place-items:center;min-width:320px;min-height:100vh}h1{font-size:3.2em;line-height:1.1}button{border-radius:8px;border:1px solid transparent;padding:.6em 1.2em;font-size:1em;font-weight:500;font-family:inherit;background-color:#1a1a1a;cursor:pointer;transition:border-color .25s}button:hover{border-color:#646cff}button:focus,button:focus-visible{outline:4px auto -webkit-focus-ring-color}@media (prefers-color-scheme: light){:root{color:#213547;background-color:#fff}a:hover{color:#747bff}button{background-color:#f9f9f9}}body{margin:0;padding:0;height:100vh;font-family:Arial,sans-serif;background-color:#f2f2f2;display:flex;justify-content:center;align-items:center}.app{text-align:center}.calculator{background:#fff;padding:20px;border-radius:16px;box-shadow:0 8px 20px #0003;width:300px}.display{background:#f9f9f9;border:2px solid #ddd;padding:10px;border-radius:10px;margin-bottom:10px;text-align:right}.expression{font-size:20px;color:#333}.result{font-size:28px;font-weight:700;color:#000}.buttons{display:grid;grid-template-columns:repeat(4,1fr);gap:10px}button{padding:20px;font-size:18px;border:none;border-radius:8px;background-color:#e0e0e0;cursor:pointer;transition:background .3s}button:hover{background-color:#d4d4d4}.span-two{grid-column:span 2;background-color:#ff8a65;color:#fff}.span-two:hover{background-color:#e57373}
