Calculator Design with html + CSS

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link rel="stylesheet" href="Style.css">
    <title>Calculator Project</title>
<style>
    *{
    padding: 0px;
    margin: 0px;
}
h1{
    text-align: center;
}
.card{
    max-width: 350px;
    margin: 0 auto;
    text-align: center;
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2);
    transition: .3s;
    margin-top: 10px;
    font-size: 0px; /* for font auto padding off*/
    padding: 5px
}
.card:hover{
    box-shadow: 0 16px 32px 0 rgba(0, 0, 0, 0.5);
}
.calc-head #result{
    width: 335px;
    height: 100px;
    font-size: 50px;
    text-align: right;
    padding: 0 5px;
    letter-spacing:3px;
}
.calc-body{

}
.btn{
    font-size: 30px;
    font-weight: bold;
    width: 87px;
    height: 80px;
    background-color: #1f2326;
    color: white;
    border: 1px solid white;   
}
.btn-style{
    background-color: rgb(72, 16, 185);
}
.btn:hover{
    background-color: black;
}
.btn-style:hover{
    background-color: rgb(47, 11, 119);
}
.btn-style-equl{
    background-color: rgb(236, 171, 31);
}
.btn-style-equl:hover{
    background-color: rgb(194, 134, 5);
}
</style>
</head>
<body>
    <h1>Calculator</h1>
    <div class="card">
        <div class="calc-head">
            <input type="text" id="result" maxlength="10">
        </div>
        <div class="calc-body">
           <div>
            <input type="button" class="btn" value="C">
            <input type="button" class="btn" value="+/-">
            <input type="button" class="btn" value="%">
            <input type="button" class="btn btn-style" value="/">
           </div>
           <div>
            <input type="button" class="btn" value="7">
            <input type="button" class="btn" value="8">
            <input type="button" class="btn" value="9">
            <input type="button"  class="btn btn-style" value="*">
           </div>
           <div>
            <input type="button" class="btn" value="4">
            <input type="button" class="btn" value="5">
            <input type="button" class="btn" value="6">
            <input type="button" class="btn btn-style" value=".">
           </div>
           <div>
            <input type="button" class="btn" value="1">
            <input type="button" class="btn" value="2">
            <input type="button" class="btn" value="3">
            <input type="button" class="btn btn-style" value="+">
           </div>
           <div>
            <input type="button" class="btn" value="0">
            <input type="button" class="btn" value=".">
            <input type="button" class="btn" value="DEL">
            <input type="button" class="btn btn-style-equl"  value="=">
           </div>
        </div>
    </div>
</body>
</html>

Answer