cal.css

body {
    font-family: 'Arial', sans-serif;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
    margin: 0;
    font-size: 17px;
    background: #fafafa;
}
h1 {
    margin: 5px 0 15px 0;
    text-align: center;
    text-transform: uppercase;
    font-size: 20px;
    letter-spacing: 1px
}
.calculator {
    width: 400px;
    padding: 20px;
    border: 4px solid #60712F;
    border-radius: 5px;
    background: #ffffff;
}
label, input, button, select {
    margin: 10px 0;
}
input {
    display: block;
    width: calc(100% - 20px);
    padding: 10px;
}
select {
    display: block;
    width: 100%;
    padding: 10px;
}
button {
    background-color: #000;
    color: #fff;
    outline: 0;
    border: 0;
    padding: 10px 15px;
    cursor: pointer;
    font-size: 16px;
    margin: 0 auto; 
    border-radius: 5px;
    margin-bottom: 5px;
}
hr {
    margin: 15px 0;
}
h4 {
    margin-bottom: 0;
}
body {
    margin: 0;
    padding: 0;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: url('https://images.unsplash.com/photo-1534787238916-9ba6764efd4f?q=80&w=1931&auto=format&fit=crop&ixlib=rb-4.0.3&ixid=M3wxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8fA%3D%3D') center/cover no-repeat;
    position: relative;
    overflow: hidden;
}

body::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: inherit;
    filter: blur(10px); /* Adjust the blur intensity */
    z-index: -1;
}