style.css

* {
    font-family: 'Times New Roman', Times, serif;
    box-sizing: border-box;
}

html {
    height: 100%;
}

body {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100%;
}

.converter {
    background: #e7c6ff;
    padding: 10px 20px;
    border-radius: 10px;
    box-shadow: 0px 4px 16px 2px rgba(0, 0, 0, 0.2);
    -webkit-border-radius: 10px;
    -moz-border-radius: 10px;
    -ms-border-radius: 10px;
    -o-border-radius: 10px;
}

.converter>.title {
    display: flex;
    align-items: center;

}

.converter>.title svg {
    width: 30px;
    margin-right: 5px;
    color: #0096c7;
}


.converter>.title>h1 {
    font-size: 18px;
    font-weight: 900;
}

#convertForm>div {
    display: flex;
    flex-direction: column;
    margin: 10px 0;
    color: #5390d9;
}

#convertForm>div>input,
#convertForm>div>select {
    border: 1px solid rgba(210, 207, 207);
    padding: 12px;
    border-radius: 6px;
    -webkit-border-radius: 6px;
    -moz-border-radius: 6px;
    -ms-border-radius: 6px;
    -o-border-radius: 6px;
    box-shadow: 8px 3px 15px rgba(0, 0, 0, 0.1);
    background: #ff8fa3;
    color: #10451d;
}


#convertForm>button {
    width: 100%;
    background: #40916c;
    color: #480ca8;
    border: none;
    padding: 10px;
    margin: 6px 0;
    cursor: pointer;
}




#convertResult {
    width: 100%;
    margin: 20px 0;
    font-weight: 900;
}

#convertResult.error {
    color: red;
    padding: 20px;
}