/* Reset */
*{
    margin:0;
    padding:0;
    box-sizing:border-box;
}

/* Body */
body{

    min-height:100vh;

    display:flex;

    flex-direction:column;

    justify-content:center;

    align-items:center;

    background:#5a08e7;

    font-family:Arial,sans-serif;

}

/* Calculator Box */
.calculator{

    width:340px;

    background:#2d2d2d;

    padding:20px;

    border-radius:15px;

    box-shadow:0 0 20px rgba(0,0,0,.4);

}

/* Display */
#display{

    width:100%;

    height:70px;

    margin-bottom:20px;

    border:none;

    border-radius:10px;

    font-size:30px;

    text-align:right;

    padding:10px;

    outline:none;

}

/* Buttons Grid */
.buttons{

    display:grid;

    grid-template-columns:repeat(4,1fr);

    gap:10px;

}

/* Buttons */
button{

    height:65px;

    border:none;

    border-radius:10px;

    font-size:22px;

    cursor:pointer;

    background:#444;

    color:white;

    transition:.3s;

}

button:hover{

    background:#666;

}

.equal{

    background:#ff9800;

}

.equal:hover{

    background:#ffb300;

}

/* Footer */

footer{

    margin-top:25px;

    color:#fff;

    font-size:18px;

    letter-spacing:1px;

    text-align:center;

    animation:fadeIn 2s ease;

}

footer span{

    color:#ff9800;

    font-weight:bold;

}

/* Animation */

@keyframes fadeIn{

    from{

        opacity:0;

        transform:translateY(15px);

    }

    to{

        opacity:1;

        transform:translateY(0);

    }

}