* {
    box-sizing: border-box;
}

body {
    margin: auto;
    width: 90%;
}

main {  
    margin: auto;
    width: 30%;
}

main p {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    font-size: 1.5em;
    margin-bottom: 50px;
    padding-top: 20px;
    text-align: center;
}

main p .version {
    color: #2b2a2a;
    font-size: 0.7em;
}

/* WRAPPER */
.calculator {
    background-color: #f1f1f1;
    border: 0.03em solid #e4e4e4;
    border-radius: 0.5em;
    padding: 4px;
}

.calculator:hover {
    background-color: #EFF4FA;
}

.display input {
    background: transparent;
    border: none;
    color: #000;
    font-family: technology, digital-7, digital, 'Lucida Sans', 'Lucida Sans Regular', 'Lucida Grande', 'Lucida Sans Unicode', Geneva, Verdana, sans-serif;
    font-size: 3em;
    height: 2em;
    padding-top: 40px;
    text-align: right;
    width: 99%;
}

table td {
    background-color: transparent;
    width: 100%;
}

table td input {
    background-color: transparent;
    border: 0.03em solid #e4e4e4;
    border-radius: 0.25em;
    font-size: 1.3em;
    height: auto;
    margin: auto;
    padding: 0.5em;
    width: 4em;
}

table td input:hover {
    background-image: linear-gradient(#fff,#f4f4f4);
}

/* SPECIFICS */
#equals {
    background-color: #0067C0 !important;
    border: none;
    border-radius: 0.25em;
    color: #fff;
}

#equals:hover {
    background-image: linear-gradient(#0067C0, #0040C0);
}

.function, .operator {
    background-color: #f8f8f8 !important;
}

#zero, #one, #two, #three, #four, #five, #six, #seven, #eight, #nine, #plusminus, #decimal {
    background-color: #fff;
}