h1 {
    text-align: center;
}

.container {
    box-shadow: 0 4px 4px lightgray;
    padding: 20px;
    max-width: 600px;
    margin-top: 20px;
    margin-left: auto;
    margin-right: auto;
    font-family: arial;
    min-width: fit-content;
}

form {
    display: flex;
    flex-direction: column;
}

input,
select,
textarea {
    padding: 10px;
    border: 1px green solid;
    border-radius: 4px;
}

label {
    font-weight: bold;
}

input:valid,
select:valid,
textarea:valid {
    border: 1px green solid;
    border-radius: 4px;
}

input:invalid,
select:invalid,
textarea:invalid {
    border: 1px solid red;
}

input:focus,
textarea:focus {
    border-color: black;
}

.radio-group legend {
    font-weight: bold;
}

.radio-group label {
    font-weight: normal;
}

.radio-group input[type="radio"] {
    height: 20px;
    width: 20px;
}

.radio-group input[type="radio"]:checked + label {
    color: green;
}

.radio-group input[type="radio"]:checked {
    border: 1px solid green;
    background-color: green;
    box-shadow: 0 2px 2px lightgray;
    accent-color: green;
}

button {
    width: 100%;
    padding: 10px;
    margin-top: 15px;
    color: white;
    background-color: green;
    border: 0;
    border-radius: 5px;
}

button:hover {
    background-color: black;
}

.navigation a {
    margin: 10px;
}