*{
	margin: 0 auto;
	max-width: 100%;
}
.calculator {
	text-align: center;
	margin: 0 auto;
	padding-top: 200px;
}

.calculator-screen {
	width: 100%;
	height: 100px;
	background-color: #252525;
	color: #fff;
	text-align: right;
	font-size: 36px;
	border: none;
	padding: 0px 20px;
	box-sizing: border-box;
}
 
.calculator-keys {
	width: 100%;
}

.row {
	display: flex;
}

button {
	height: 80px;
	background-color: gray;
	border: 1px solid black;
	font-size: 32px;
	color: #fff;
	width: 25%;
	outline: none;
}

.all-clear,
.zero-btn {
	width: 50%;
}

.operator,
.equal-sign {
	background-color: orange;
}

button:hover {
	background-color: darkgray;
}

.operator:hover,
.equal-sign:hover {
	background-color: darkorange;
}
header{
    background-color:#35BDD0;
    color: #fff;
    max-width: 100%;
    padding: 2rem;
    border-bottom-left-radius: 2rem;
}
header h1{
    font-family: 'Times New Roman', Times, serif;
    font-size: 3rem;
    font-weight: bold;
} 

/* @media(max-width: 700px) {
    footer{
		display: none;
            bottom: 0%; 
			position:absolute;
            /* position: ; */
          
     
    /* }  
} */ 