style.css

@font-face { 
    font-family: avenir;
    src: url(./Fonts/Avenir.ttc);
}

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

body { 
    font-family: avenir;
}

header { 
    width: 100%;
    height: 55px;
    background-color: #1A1A1A;
}

main { 
    width: 90%;
    margin: 0 auto;
}

#header_content { 
    width: 90%;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;   
}

#header_image { 
    height: 18px;
    margin: auto 0;
    margin-top: 37.1px;
}

#menu_main { 
    background-color: #1A1A1A;
    padding: 1.5em 0;
    width: 100%;
}

ul.navigation {
    width: 90%; 
    margin: 0 auto;
    list-style-type: none;
    text-align: right;
}

ul.navigation > li { 
    margin: 0.1em 0;
}

.menu_header { 
    height: 18px;
    width: auto;
}

.header_back_icon { 
    width: 31px;
    height: auto;
    padding-top: 17.25px;
}

.header_close_icon { 
    width: 31px;
    height: auto;
    padding-top: 15px;
}

.header_icon { 
    width: 31px;
    height: auto;
    padding-top: 19.24px;
}

.dummy { 
    width: 31px;
}

.intro { 
    margin: 0.75em auto 0.5em auto;
}

.info_container, .info_container_plan { 
    margin: 0 auto;
    border-top: 1px solid #B7B7B7;
}

.info_container_plan { 
    border-bottom: 1px solid #B7B7B7;
}

.choices_container { 
    width: 95%;
    margin: 0.5em auto;
}

.data_container { 
    display: flex;
    align-items: center;
}

.data_container > input { 
    margin: 0.3em 0.5em;
    width: 20px;
    height: 20px;
}

.choice_container > p { 
    margin: 0 0.5em;
}

.choice_container { 
    align-items: center;
    background-color: #EBE9E9;
    display: flex;
    flex-direction: row;
    justify-content: space-between;
    border-radius: 5px;
    margin: 0.5em 0;
}

#selected { 
    background-color: #FF2E2E;
}

.logo { 
    width: 65px;
    height: auto;
}

.plan_info, .provider_info { 
    display: flex;
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
    width: 95%;
    margin: 0.5em auto;
}

.plan_icon { 
    width: 17.5px;
    height: 17.5px;
    margin-left: 1em;
}

.contact_info { 
    font-size: 14px;
    display: flex;
    flex-direction: row;
    flex-wrap: nowrap;
    justify-content: flex-start;
    align-content: center;
    width: 95%;
    margin: 0.5em auto;
}

.contact_info_data { 
    margin: 0 0.5em;
}

.contact_icon { 
    width: 20px;
    height: 20px;
}

.support_info { 
    width: 95%;
    margin: 0.5em auto;
    font-size: 14px;
}

.support_info_container { 
    display: flex;
    flex-direction: row;
    align-items: center;
    margin: 0.5em 0;
}

.provider_text { 
    width: 70%;
}

a { 
    text-decoration: none;
}

a:link { 
    color: black;
}

a:visited { 
    color: black;
}

.total { 
    border-top: 1px solid #B7B7B7;
    margin: 1em auto 0.5em auto;
    padding: 0.5em 2.5%;
    display: flex;
    flex-direction: row;
    justify-content: space-between;
}

.buttons { 
    width: 95%;
    margin: 0 auto;
    display: flex;
    flex-direction: row;
    justify-content: space-between;
}

.buttons > a { 
    background-color: #FF2E2E;
    padding: 0.3em 0.5em;
    border-radius: 5px;
    color: white;
}

.buttons > a#gray { 
    background-color: #EBE9E9;
    color: black;
}

form { 
    display: flex;
    flex-direction: column;
    border-top: 1px solid #B7B7B7;
    padding: 0 2.5%;
}

input[type=text], input[type=email], input[type=date] { 
    font-family: avenir;
    font-size: 16px;
    width: 100%;
    height: 40px;
    background-color: #EBE9E9;
    border: none;
    border-radius: 7px;
    padding: 10px 20px;
}

input[type=text]:focus { 
    border: 1px solid #B7B7B7;
}

.voornaam_tussenvoegsel > input { 
    width: 47.5%;
}

.voornaam_tussenvoegsel { 
    height: 75px;
    display: flex;
    flex-wrap: wrap;
    flex-direction: column;
    justify-content: space-between;
    align-content: space-between;
}

select { 
    font-family: avenir;
    font-size: 16px;
    width: 100%;
    height: 40px;
    background-color: #EBE9E9;
    border: none;
    border-radius: 7px;
    padding: 10px 20px;
}

label {
    font-size: 18.72px;
    font-weight: bold;
}

label.thin { 
    font-size: 16px;
    font-weight: normal;
}

input[type=submit] { 
    width: 25%;
    background-color: #FF2E2E;
    padding: 0.3em 0.5em;
    border-radius: 5px;
    color: white;
    border: none;
    font-family: avenir;
    font-size: 16px;
    font-weight: bold;
}

input[type=submit]#order { 
    width: 32%;
}

select:focus { 
    border: 1p solid #B7B7B7;
}

.form_element { 
    margin: 0.5em 0;
}

.radio_buttons { 
    display: flex;
    flex-wrap: wrap;
    flex-direction: row;
    align-items: center;
    width: 20%;
}

.radio_buttons > input { 
    margin: 0.3em 0.5em;
    width: 20px;
    height: 20px;
}

footer { 
    background-color: #1A1A1A;
    text-align: center;
    color: white;
    font-size: 10px;
    margin-top: 1em;
}