body {
            background: linear-gradient(#9C27B0,#FF9800);
            min-height: 100vh;
            padding: 20px;
            font-family: Arial;
            margin: 0;
        }

        .header {
            text-align: center;
            margin-bottom: 50px;
        }

        h1 {
            color: white;
            font-size: 45px;
            margin-bottom: 10px;
        }

        .subtitle {
            color: white;
            font-size: 22px;
        }

        .menu-container {
            max-width: 600px;
            margin: 0 auto;
        }

        .menu-button {
            background-color: white;
            padding: 30px;
            margin: 15px 0;
            border-radius: 15px;
            text-align: center;
            cursor: pointer;
            transition: transform 0.2s;
            text-decoration: none;
            display: block;
            color: #333;
        }
     /*Відповідає за анімацію */
        .menu-button:hover {
            transform: scale(1.05);
        }

        .menu-icon {
            font-size: 50px;
            margin-bottom: 10px;
        }

        .menu-title {
            font-size: 32px;
            font-weight: bold;
            margin-bottom: 5px;
        }

        .menu-desc {
            font-size: 18px;
            color: #666;
        }

        .btn-addition {
            border-left: 8px solid #4CAF50;
        }

        .btn-subtraction {
            border-left: 8px solid #FF9800;
        }

        .btn-multiplication {
            border-left: 8px solid #9C27B0;
        }

        .btn-division {
            border-left: 8px solid #2196F3;
        }

        .footer {
            text-align: center;
            margin-top: 50px;
            color: white;
            font-size: 18px;
        }