body, ul, li, h1, h2, a{
    margin: 0;
    padding: 0;
    font-family: arial;
}

header {
    background-color: #0968f7fd;
    padding: 1px;
    text-align: center;
    position: fixed;
    width: 100%;
    z-index: 1;
    top: 0px;
    left: 0px
}
header h1{
    color: white;
    border: 8px solid white;
    padding: 6px 12px;
    display: inline-block;
    border-radius: 36px;
}

.banner{
    position: relative;

}

.bannerc img{
    max-width: 100%;
}

.banner .welcome{
    background-color: #e96060;
    color: white;
    padding: 30px;
    position: absolute;
    left: 0px;
    top: 30px;
}

.banner h2{
    font-size: 74px;
}

.banner h2 span{
    font-size: 1.3em;
}

nav{
    background-color: #afd4ecdc;
    padding: 20px;
    position: sticky;
    top: 106px;
}

nav ul{
    white-space: nowrap;
    max-width: 1000px;
    margin: 0 auto;
}
nav li{
    width: 25%;
    display: inline-block;
    font-size: 24px;
}

nav li a{
    text-decoration: none;
    color: #4b4b4b;

}
nav li a .join{
    color: #f51111;
}

main{
    max-width: 100%;
    width: 1200px;
    margin: 80px auto;
    padding: 0 40px;
    box-sizing: border-box;
}

article h2{
    color: #F63232;
    font-size: 46px;
    text-align: center;
}

article p{
    line-height: 2em;
    color: #4b4b4b;
}

article h3{
    font-size: 1.2em;
    color: #4b4b4b;
}

.images{
    text-align: center;
    margin: 80px 0;
    white-space: nowrap;
}

.images li{
    display: inline-block;
    width: 40%;
    margin: 20px 5%;
}

.images li img{
    max-width: 100%;
}

section.join{
    background-color: #f4f4f4;
    text-align: center;
    padding: 60px 20px;
    color: #4b4b4b;
}

.join h2{
    font-size: 36px;
}

form input{
    margin: 20px 0px;
    padding: 10px 20px;
    font-size: 24px;
    border-radius: 28px;
    border: 4px solid white;
}

footer{
    background-color: #0968f7de;
    color: white;
    padding: 10px;
    text-align: center;
}

/* pseudo classes */

nav li a:hover{
    text-decoration: underline;
    background-color: #ff9898cb;
    padding: 3px;
}

.images li:hover{
   position: relative;
   top: -4px; 
}

form input:focus{
    border: 4px dashed #4b4b4b4b;
    outline: none;
}

form input:valid{
    border: 4px solid #71d300;
}

article p::first-line{
    font-size: 1.2em;
}
article h3::first-line{
    font-size: 1.2em;
}
p::selection{
    background-color: red;
    color: white;
}

/* Responsive style */

@media screen and (max-width: 1400px){

    .banner .welcome h2{
        font-size: 60px;
    }

    nav li{
        font-size: 18px; 
    }
}

@media screen and (max-width: 960px){

    .banner .welcome h2{
        font-size: 40px;
    }
}

@media screen and (max-width: 700px){

    .banner .welcome{
        position: relative;
        text-align: center;
        padding: 10px;
    }
    .banner .welcome br{
        display: none;
    }
    .banner .welcome h2{
        font-size: 25px;
    }
    .banner .welcome span{
        font-size: 1em;
    }
    .images li{
        width: 100%;
        margin: 20px auto;
        display: block;
    }
}

@media screen and (max-width: 560px){

    nav li{
        font-size: 20px;
        display: block;
        width: 100%;
        margin: 12px 0;
    }
    header{
        position: relative;
    }
    nav{
        top: 0;
    }
}