.form__field {
    margin-bottom: 10px;
}

.form__error {
    color: red;
    text-align: left;
    font-size: 12px;
    display: block;
    margin-top: 3px;
    display: none;
}

.form input {
    outline: none;
    display: block;
    width: 100%;
    border-radius: 2px;
    border: 1px solid #ccc;
    padding: 10px;
    box-sizing: border-box;
}

.form button {
    width: 100%;
    padding: 10px;
    border-radius: 2px;
    border: 0;
    background-color: #ccc;
    color: #fff;
}

input:valid:not(:placeholder-shown) {
    border-color: green;
}

input:invalid:not(:placeholder-shown) {
    border-color: red;
}
input:invalid:not(:placeholder-shown) + .form__error {
    display: block;
}
input.checkbox-agreement {
    position: relative;
    cursor: pointer;
    margin-right: 13px;
}
input.checkbox-agreement:before {
    content: "";
    display: block;
    position: absolute;
    width: 20px;
    height: 20px;
    top: 0;
    left: 0;
    background-color:white;
    border: #bbb solid 1px;
}
input.checkbox-agreement:checked:before {
    content: "";
    display: block;
    position: absolute;
    width: 20px;
    height: 20px;
    top: 0;
    left: 0;
    background-color:white;
}
input.checkbox-agreement:checked:after {
    content: "";
    display: block;
    width: 10px;
    height: 10px;
    position: absolute;
    top: 5px;
    left: 5px;
    background: green;
}

#agreement-text p {
    line-height: 20px;
}