* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body{
    background-color: #333;
    color: #fff;
    font-family: Arial, Helvetica, sans-serif;
}

header{
    background-color: cadetblue;
    padding: 15px;
    text-align: center;
    margin-bottom: 30px;
}

main{
    text-align: center;
}

textarea, select, button{
    width: 300px;
    border: 2px solid #999;
    background: transparent;
    border-radius: 5px;
    padding: 10px;
    font-size: 17px;
    color: #fff;
    outline: 0;
}

textarea{
    height: 200px;
}

select, button{
    display: block;
    margin: 10px auto;
    font-weight: bold;
}

option{
    background-color: #333;
}

select:disabled, 
button:disabled{
    
    opacity: .1;
}