style.css

body {
    background-color: #FF9E0D;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
}

a {
    color: #fff;
    text-decoration: none;
}



table {
    margin: auto;
    background-color: #000;
    position: relative;
    width: 500px;
    height: 600px;
    padding: 25px;
    text-align: center;
    border-radius: 10px;
}

table tr {
    display: flex;
    justify-content: center;
}

table tr:first-child {
    max-width: 95%;
}

table tr:first-child td input:hover,
table tr:first-child td input:focus {
    pointer-events: none;
}

table tr:first-child td {
    width: 100%;
}

table tr:last-child td p {
    position: absolute;
    font-size: 15px;
    right: 30px;
}

table tr:last-child td p:first-child {
    bottom: 10px;    
}

table tr:last-child td p:last-child {
    bottom: 30px;
}

table tr td {
    margin: 5px 0;
    display: inline-block;
}

td p {
    margin: 5px 0;
    font-size: 25px;
    letter-spacing: 3px;
    color: #fff;
    font-weight: bold;
}

input {
    outline: 0;
    position: relative;
    border: 0;
    top: 0;
    color: #0d6efd;
    background-color: #fff;
    box-shadow: 0 6px 0 #0248b1;
    border-radius: 4px;
    width: 98px;
    height: 60px;
    margin: 5px;
    font-size: 40px;
    transition: all 0.2s ease-in-out 0s;
}

input:hover,
input:focus {
    top: 4px;
    cursor: pointer;
    box-shadow: 0 2px 0 #0248b1;
}

#display {
    width: 100%;
    font-size: 60px;
    text-align: center;
    background-color: #F1FAEB;
    float: left;
    height: 100px;

}

.operator {
    color: #fff;
    background-color: #0d6efd;
}

.clear {
    color: #fff;
    background-color: #dc3545;
}

input.operator,
input.operator,
input.clear,
input.clear {
    box-shadow: 0 6px 0 #fff;
}

input.operator:hover,
input.operator:focus,
input.clear:hover,
input.clear:focus {
    box-shadow: 0 2px 0 #fff;
}