header {
  background-color: #e67be8;
  padding: 20px;
  text-align: center;
  position: fixed;
  width: 100%;
  z-index: 1;
  top: 0;
  left: 0;
}
header h1 {
  color: white;
  border: 8px solid white;
  padding: 6px 12px;
  display: inline-block;
  border-radius: 36px;

}
.banner {
  position: relative;
}
.banner img {
  max-width: 100%;
  width: 2000px;
  height: 500px;
}
.banner .welcome {
  color: rgb(198, 42, 117);
  padding: 30px;
  position: absolute;
  left: 0;
  top: 60%;
  font-family: 'Franklin Gothic Medium', 'Arial Narrow', Arial, sans-serif;
}
.banner h2 {
  font-size: 74px;
}
.banner h2 span {
  font-size: 1.3em;
}
nav {
  background-color: #f4f4f4;
  padding: 20px;
  position: sticky;
  top: 106px;
}
nav ul {
  white-space: nowrap;
  max-width: 1200px;
  margin: 0 auto;
}
nav li {
  width: 25%;
  display: inline-block;
  font-size: 24px;
}
nav li a {
  text-decoration: none;
  color: #bd5899;
}
nav li a.join {
  color: #ec31c3;
}
main {
  max-width: 100%;
  width: 1200px;
  margin: 80px auto;
  padding: 0 40px;
  box-sizing: border-box;
}
article h2 {
  color: #ff6ba9;
  font-size: 48px;
}
article p {
  line-height: 2em;
  color: #4b4b4b;
}
.images {
  text-align: center;
  margin: 80 px 0;
  white-space: nowrap;
}
.images li {
  display: inline-block;
  width: 40%;
  margin: 20px 5%;
}
.images li img {
  max-width: 100%;
}
section.join {
  background: #f4f4f4;
  text-align: center;
  padding: 60px 20px;
  color: #4b4b4b;
}
.join h2 {
  font-size: 36px;
}

footer {
  background: #d532f6;
  color: white;
  padding: 10px;
  text-align: center;
}

/* pseudo classes */

nav li a:hover {
  text-decoration: underline;
  background-color: rgba(255, 0, 251, 0.41);
  padding: 3px;
}

.images li:hover {
  position: relative;
  top: -4px;
}
form input:focus {
  border: 4px dashes #4b4b4b;
  outline: none;
}
form input:valid {
  border: 4px solid #71d300;
}
nav li:first-child {
  border: 0;
}
nav li:second-child {
  border: 3px solid pink;
}

/* responsive styles*/
@media screen and (max-width: 1400px) {
  .banner .welcome {
    font-size: 60px;
  }
  nav li {
    font-size: 18px;
  }
}

@media screen and (max-width: 960px) {
  .banner .welcome h2 {
    font-size: 28px;
  }
  nav li {
    font-size: 18px;
  }
}

@media screen and (max-width: 700px) {
  .banner .welcome {
    position: relative;
    text-align: center;
  }
  .banner .welcome br {
    display: none;
  }
  .banner .welcome span {
    font-size: 1em;
  }
  nav li {
    font-size: 18px;
  }
  .images li {
    width: 100%;
    display: block;
    margin: 20px auto;
  }
}
@media screen and (max-width: 560px) {
  nav li {
    font-size: 20px;
    display: block;
    margin: 12px 0;
  }
  header {
    position: relative;
  }
  nav {
    top: 0;
  }
}